How Quickly Can You Lose Weight?

Take your average guy or gal that decides they’re committed to finally losing that extra weight that’s crept on over the years. They’re going to eat healthy (primally, of course), start working out, and stop all the nonsense they know to be unhealthy. This might be you.

A few days go by, then a week. The scale is budging, but barely. “This is going to take forever! How long is this going to take?” We all want instant results, right? Well, what is realistic? What is safe? What is effective? And what can you expect when you attempt to lose excess body fat and reach your ideal body composition?

Everyone knows that slow, gradual weight loss produces the best long-term results and fast weight loss is unsafe and unhealthy. People you know have probably clucked “Oh, you’re losing weight fast now with that low-carb fad diet, but just wait a few weeks and it’ll all come rushing back!” And when you go somewhere like the CDC’s weight loss page, they pat your head for “want[ing] to lose it very quickly” and reassure you that “people who lose weight gradually and steadily are more successful at keeping it off.” It’s become an article of faith that slow and steady weight loss wins the race.

But is it actually true?

I searched the literature for support of this widely-accepted weight loss truth. If folks like the Center for Disease Control were saying it, there had to be some evidence for it. Right?

I came up empty. What little evidence I could find seemed to support the opposite contention: that rapid initial weight loss is associated with better long term weight maintenance than slower weight loss. Just look:

What Research Reveals About Rapid Weight Loss

  • A 2000 review concluded that “greater initial weight loss” improves long term weight loss maintenance, even when that weight is lost using extreme diets.
  • A 2001 review concluded that the use of very low calorie diets to spur rapid short term weight loss can be highly effective for long term weight maintenance, provided subjects follow up with a “weight-maintenance program” including physical activity, nutritional education, and behavioral therapy.
  • A 2004 review of the effect of “lack of realism” in weight loss goals on long term weight maintenance found that “higher dream weight loss goals” were linked to greater weight loss at 18 months.
  • There was the paper from 2010 showing that among middle-aged obese women, those who lost weight the fastest were the most likely to keep it off after 18 months.
  • There was also a more recent paper where people who lost weight quickly were no more likely than people who lost it slowly to regain the weight in the long term. Members of the fast weight loss group were more likely to hit their short term weight loss goals (12.5% reduction in body weight) and stick with the program. Even though both groups had regained about 70% of the lost weight after three years, the net weight loss in the fast weight loss group was greater.

Across most of the available literature, slow and steady did not win the race. The hare usually beat the tortoise. This actually makes sense. Why is the ancestral health community so strong? Why does this site attract so many readers? In part, because of the ease, simplicity, and early efficacy of this way of eating. Right off the bat (or in just 21 days), you lose weight, feel better, and regain lost energy. Why wouldn’t you keep doing it? You’re more likely to stick with a diet if you’re wildly successful right away.

Okay, okay. But is rapid weight loss safe?

It depends on who you are.

If you’re obese, rapid weight loss is safe, since as much as 87% of the total weight you lose will be body fat. And just as dietary fat is an excellent fuel source that burns cleanly, the animal fat hanging off your body is good to burn. That’s why rapid weight loss in the obese is consistently associated with improved health markers. Insulin sensitivity increases and belly fat decreases. Blood lipids normalize. Testosterone increases and sexual function is restored. Oxidative stress biomarkers are reduced. All sorts of wonderful things happen when you’re overweight or obese and start losing weight.

If you’re lean, rapid weight loss looks a little different. The leaner you are, the more muscle mass you’ll lose during weight loss and the more negative effects you’ll accrue. An extreme example of this is the bodybuilder preparing for competition. He’s reducing calories. He’s exercising. He’s doing everything he can to drop weight as quickly as possible. And in dropping from 14.8% body fat to 4.5%, he loses strength, his testosterone plummets, and his mood worsens — the opposite of what happens to the obese when they drop weight fast.

Another population for whom rapid weight loss might be contraindicated is the elderly. If you’re elderly, rapid weight loss is usually associated with illness and accelerated muscle loss, and it’s a frequent complication of Alzheimer’s disease. Slower weight loss using a diet rich in protein (to stave off muscle loss) and regular physical activity is a better option for older people.

It also depends on how you do it. Let’s look at some of the methods used to cause rapid weight loss.

Pros and Cons of Common Weight Loss Strategies

Dehydration-Based Weight Loss

Athletes who need to make weight to qualify for competition, like MMA fighters or bodybuilders, often do so by quickly dropping water weight. They’ll go jogging in full black sweatsuits. They’ll sit in saunas. They’ll remove all salt from their diet (since sodium helps us retain water). They’ll go super low-carb (since stored glycogen brings water along for the ride). They’ll take hot baths and stop drinking water altogether on the day of the weigh-in. That’s how a fighter who normally walks around at 195 pounds can qualify for the 170 pound division — by dehydrating himself.

Verdict: Not safe. Dehydration impairs physical performance, cognitive function, and connective tissue elasticity. Plus, it’s literally just water weight that will come screaming back once you start eating carbs, salt, and drinking water again.

Very Low-Calorie Dieting

This might be the most common method people employ to achieve fast weight loss: eat barely anything. And there are studies supporting the efficacy of very low-calorie dieting (VLCD), but when your average person with weight to lose hears that and just stops eating (usually supplemented with lots of cardio), it’s disastrous. Clinical VLCDs have very specific guidelines. Before patients are selected, they undergo a physical and go over their medical history. Once on the diet, they receive counseling, supplements, premade food (often liquid), and regular checkups to identify nutrient deficiencies and side effects. They’re meant for the obese, not someone who wants to lose a few stubborn inches off their belly.

Verdict: Safe, but you’d better know what you’re doing. Professional supervision is probably a good idea if you intend on making this work long-term.

Protein-Sparing Modified Fasts

Protein-sparing modified fasts (PSMFs) are a type of very low-calorie diet, but calories aren’t the express focus; getting enough protein and then stopping is the focus. You eat as much protein, preferably from animal sources, as you require to curb loss of lean mass and maximize fat loss, then add heaps of low-carb vegetables. PSMFs are high-protein, low-carb, and low-fat diets. A PSMF might look this:

  • Minimum 1.5 grams of protein per kg of lean body mass (if sedentary; closer to 2 g/kg if strength training) from lean meats and protein powders like whey isolate.
  • Unlimited fibrous vegetables (spinach, lettuce, kale, chard, broccoli, asparagus, etc; anything without an appreciable number of digestible carbs).
  • Three to four grams of fish oil.
  • Multivitamin/mineral supplement.
  • Cook with little to no added fat. Eat no fruit, sugar, or starches.

In the fitness/weight loss community, people will typically maintain this for 1-2 weeks, then do a refeed and hop back on it, or resume a more normal diet. Clinical use of the PSMF in severely obese people usually lasts longer than one or two weeks and is quite effective:

  • In obese patients, a PSMF allowed 47 +/- 29 pounds of weight loss. By the end of the maintenance period, most of the weight was still missing, so it was pretty successful (particularly in those who had the most to lose).
  • A 2 week 400 calorie PSMF was safe and effective in obese patients, especially compared to a 400 calorie liquid protein diet.

Every study I could find on PSMFs found they worked and were safe, with some caveats:

In obese teens, a 3-month long PSMF supplemented with potassium, calcium, and magnesium resulted in weight loss and maintenance of normal serum concentrations of the supplemented minerals. But when researchers looked at red blood cell levels of the minerals — which offers a more accurate glimpse of mineral status than serum level — they found that RBC magnesium had plummeted. It’s likely that other micronutrient-related biomarkers could also suffer.

Verdict: Safe and effective, provided you don’t remain on the diet for too long. Extended PSMFs are more likely to cause harm and nutrient deficiencies (that may not show up in standard serum tests) than shorter PSMF bursts. Obese people in clinical settings with professional support can probably safely benefit from longer PSMFs, but the average Primal reader just trying to lean out a bit or get over a plateau should stick to 1-2 weeks.

Low-Carb, High-Fat Diets

In the population most in need of safe, effective weight loss — the millions of insulin-resistant obese and overweight individuals who do not participate in clinical weight loss trials helmed by doctors and technicians and supported by supplements and formulated diets — a basic low-carb, high-fat diet is the simplest and most effective method. Comparisons between ad libitum (where you eat until sated) low-carb diets and calorie-restricted (where you weigh and measure) diets find that the former result in faster weight loss.

Low-carb, high-fat approaches also sidestep another potential downside to rapid fat loss in general: the risk of gallstone formation. Research shows that adding some fat in the diet to promote gallbladder emptying takes care of the gallstone problem. One study found that 4 of 6 subjects on a 520 calorie liquid low-fat diet developed gallstones, while none of the 7 subjects on a 900 calorie liquid diet with 30 grams of fat developed them, even though both diets resulted in the same amount of weight loss.

One potential downside of rapid weight loss are elevations in liver enzymes. The rise is usually transient, resolving shortly after cessation of the diet, and it seems to happen more often in women than men. But the macronutrient ratio is perhaps the biggest determinant. When these very low-calorie diets are high in carbohydrates, liver enzymes are higher. When the diet is carb-restricted, the liver enzymes are lower.

Verdict: Safe and effective.

If there’s a neat and tidy answer (and there never is in a topic as complex as human physiology), it’s this: rapid weight loss is safe as long as you’re losing (mostly) fat and not lean muscle mass. If you’re dropping weight quickly (or slowly!) but you feel good, your physical performance is improving or staying the same, and you’re losing inches from the waist, your weight loss is probably mostly fat. If you’re dropping weight quickly but troublesome side effects occur, your weight loss may be drawing on more lean mass than you’d like, and you should probably slow down. Weight loss should feel good.

There’s another commonality among all the “crash” diets that end up leading to long term maintenance: they combine rapid weight loss and education. It shouldn’t just change what you put in your mouth, but how you think about what you put in your mouth. Without learning about food and how it affects you and how to eat long term in the real world, the weight’s just going to come roaring back.

With the Primal Blueprint, I’ve tried to pair education with results for a sustainable way of eating and living. There are other ways to get there, as I’ve mentioned above, but this one seems to work well for nearly everyone I know that’s tried it.

Thanks for reading, everyone. I’m curious about your thoughts on rapid weight loss.

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TAGS:  hormones

About the Author

Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.

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111 thoughts on “How Quickly Can You Lose Weight?”

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    1. Good article but science is slowly starting to show that weight loss is about more than just calories.

      Good article though nevertheless.

  1. Eat the way we are intended to eat, veggies, fruits, nuts, good meats and fish. Keep it simple! Go Grok and forget the rest!

    1. Did this last year no weight loss. Now do high protien, low carb mod fat and now have success eat very little fruit or nuts

    2. Another way I think of this is: eat what God put on the Earth for us, and our bodies are happy. Eat processed food that we have altered with chemicals, stripped of nutrients, and bolstered with overwhelming dopamine-releasing flavor and we get very sick.

  2. That’s really useful information.
    I feel like I learn something new everyday that defies conventional wisdom, including this.
    There again I would love to lose weight quickly, however as a 48 year old woman I am delighted to lose a pound a week even whne I have really stuck to low carb, high fat eating.
    When I was younger it was so much easier to lose weight.

    1. Yes, me too. I just finished the 21 day challenge and only lost 2 lbs. I followed it almost perfectly too. I wish I could lose weight faster, it just doesn’t happen for me at 42.

      1. Around age 40 (give or take 3 years) the female hormones start to change slowly. It is the (unofficial) start of Menopause (same for men).
        If left uncontrolled, women will on average add around 2-5 lbs a year to the body fat until age ~ 60 (again give or take 3 years) when the whole thing will stop to accumulate and the organs and bone (especially in the head) start feeding off the fat until death.

        Humans will start to wilt rapidely after age 70ish because the signals to ‘build up’ are turned off. It becomes HARD to maintain a youthful look.

        Weight Control starting around age 40 and lifting weights will slow this process down.

        I have never met a single human being that was 70+ and looked like they’re in their 40’s. Healthier, yes, but never Young.

    2. Try going low-carb/low-fat for a month or so. Contrary to popular belief, fat WILL PREVENT rapid weight loss if you eat enough of it. When ketogenic diets used for seizure control cause too much weight loss, dietary fat is drastically increased and weight loss stops. The body needs some dietary fat for good health, so don’t try to eliminate all of it.

      1. Huh. I’ve been doing a diet nearly identical to an anti-seizure diet for over a year now – roughly 85% of my calories from fat (this is hard to do). I’m not sure how dietary fat could be “drastically increased” from here – this is already a nearly no-carb, very low protein diet. Though one could add more food and calories overall, which would increase fat too. It would be extremely unappealing. This level of keto kills appetite.

        Incidentally, I’ve lost nearly 40 pounds this year, on top of about ten lost previously eating Primal for a year and a half. The first 18 pounds of keto weight loss happened for me in three weeks.

        1. Allison, your fat intake is already pretty high, and everyone is different. Also there are different versions of the keto diet. The one my son was on was put together for us by Children’s Hospital dietitians. It restricted calories as well as carbs (since the medically-supervised diet mimics starvation which somehow controls seizures). He did not need to lose weight but still lost 25 pounds. They tweaked his diet to incorporate “ice cream” three times a day. This was made with heavy cream, oil, and artificial sweetener. Probably not very healthy but the weight loss stopped.

          This sort of keto diet is too nutrient-poor to be healthy long term. Normally patients are on it for no more than a year. Unfortunately, it didn’t work well for him. While there were no seizures during the time he was on this diet, he had to return to meds once he got off the diet, although to a much lesser degree. This is age-related. Younger children often have a better outcome.

          If you plan to remain on your keto diet indefinitely, do make certain you get enough nutrition from real food. Although the body does need fat in order to function, it lacks sufficient nutrients on its own.

    3. Oh me three!
      Sooooo much harder to keep it off/lose it when over 40. Am quite fed-up.
      Everything is aimed towards the young or male (or both). So much more to consider when women get older.
      I don’t want to lose weight quickly, I just want to be able to lose weight!
      Any would be nice.
      Too many things to factor in, and after a while it just gets too hard and you get tired of trying to do everything and the tweeks.

      1. Do you do high intensity interval training, or some heavy weight training? After years of yo-yo low-carb dieting it had stopped working for me until I joined Crossfit – then suddenly weight began to magically fall off again. I suspect high intensity training drastically improved my insulin sensitivity.

  3. Validating.
    Thank you for an excellent post I can refer friends to.

  4. When I changed to a primal diet, I was 42 years old, 6′ 0″, and a steady 210-212 lbs. I had just run a half-marathon, so I wasn’t in bad shape. From the moment I changed my diet, I started dropping weight at the rate of a pound per day, and that held for 20 days. I lost 10 more pounds over the next 20 days, and another 4 over the next 20.

    Even when I’m not exercising for stretches at a time, my weight holds steady at 185, and it has been that way for 4.5 years now.

  5. I’ve been eating low carb high fat for 2 years and I’ve lost 40 lbs of the approximately 80 lbs I have to lose. I know the article is about losing weight quickly, but I just wanted to mention it because I think hearing mostly stories of quick weight loss can make people think that if they lose slowly there’s something wrong. Being 40 lbs lighter is great even though it took me a while to get here.

    1. My husband has lost a total of 33 lbs. over the last two years, and it’s been coming off in 5-7 lb. chunks. I don’t care how quickly or slowly it comes off–just that it COMES OFF.

    2. Thanks for your encouragement. I am eating low carb, exercising and have only seen a very slow weight loss. Congratulations for sticking with it for 2 years and losing 40 lbs.!!!

  6. I have been a wrestling coach for over 20 years and am wondering about Primal for my guys. There are always kids who need to make weight. They still after all these years do the same old thing. Cut really hard a day or two before weigh in, then gorge like crazy. I know they are “dead at the weight” when they wrestle. You would think that they would be smarter, but the truth is I CANT be with them all the time when they are away.
    With Primal, how would you recommend I get them focused on WHAT to eat and WHEN as it relates to weight loss and performing at a high level WHILE staying HYDRATED?
    coach U

    1. So if “everyone” knows that athletes cut water weight and go to unhealthy extremes to do so, why not weigh in just before the match starts? Wouldn’t that add more integrity and focus to the match/event/competition?

      I have never been apart or around this rapid weight cutting for sports so this is new to me.

    2. I have thought about this often. Though I am not a wrestling coach, I did enjoy wrestling in HS and have thought when my kids get older of volunteering or something.

      I would say the most ethical thing a coach could do is weight the kids at least two to three times a week and not let them wrestle in weight class more than about 5 lbs below their ‘normal’ weight (should be achieved by 2-3 weeks after training). Dropping 3-5 lbs in a night is pretty normal, but kids should not be allowed to wrestle more than 5-8 lbs (MAX) below their weigh in the day before a meet. As a coach, you can directly control this.

      Also reminding them that cognitive and physical function are so depleted by cutting extreme weight that it cancels out the ‘edge’ they get from wrestling at a lower weight. Oh, and that you can’t wrestle if you pass out and wind up in the hospital (happened to a guy a knew that tried to drop 25 lbs in a week right before CIF)

  7. Above all, we HAVE to remember that we didn’t gain the weight overnight, so it isn’t going to come off overnight! Does anyone here ever remember suddenly waking up with 20 extra pounds (or more) on their person? Nobody does–nobody did.

    The fastest I ever lost was 2.5 lbs. a week for about 3 months–then, I discovered a cheese I could eat without having food allergy reactions (Wensleydale). I now know that fructose stalls me like a concrete wall, and guess what Wensleydale has in it? Fruit…and fructose (even the cranberry variety does). So here I sit, stalled again, and the tricks that unstalled me the last time isn’t working this time (lowering the protein, hiking the fat, walking the neighbor’s dog, and chucking out the offending food), but since it’s winter, I have chosen to just ride the season out. I’m just thankful I stalled at a much lower weight than the last time.

    This spring, I will have a cancer survivor to walk with–I guess I’ll be walking the neighbor instead of a different neighbor’s dog! I plan to work him up to mowing his own lawn again, and possibly even riding bikes (once his energy levels return). He’s a cancer survivor, and I may as well be an obesity survivor.

    1. Hi, I read your post with great interest and was wondering if you could expand on your comments regarding fructose. I understand the evils of HFCSyrup, but fructose as a naturally occurring sugar is in…well, everything. I eat a lot of berries and apples. Some cheese, but otherwise try to follow primal bprint – diet/exercise, etc. That said, I am a 40+, 5’2, 117 lb female who ought to be around 112 and yet the weight just doesn’t budge.

      eager to hear your thoughts/ideas. thanks!

      1. There are quite a few people (including my brother) that are fructose intolerant. This makes it much more difficult to avoid sugar and eat even common vegetables (like onions) and fruits. Not saying this is your problem, but it might be something to look into.

      2. The problem is…Sugar is Sugar. It sucks, but it is the truth. Now, there are healthier types of sugar such as raw honey or apples, rather than the HFCS or refined table sugar, but they are still carbs and they still count to gaining weight. If you are eating a lot of fruits/berries, you are probably going over in carb count to where your body won’t shed weight.

    2. I have discovered it is more the type of fat I eat that effects weight loss. Saturated fat and nuts (Sad!) are the two worst. I am trying to go ‘nut free’ right now but it’s so hard. Keeping my saturated fat very low is most important. Then nuts. I only want to lose 3#’s but still…

      I eat no dairy or fruit, starch, grains or sugar. Green veg, 45-55g quality protein (mostly fish) and olive oil. Those are the staples. Then nuts and avocado for snacks.

      I think I’m going to finish the nuts I have and take a break

    3. I haven’t gained 20 pounds overnight, but I have gained 14 overnight. I have gained over 20 within 2-3 days. When I was ballooning up to 299.8, my highest weight, due to the combination of high carb low fat vegetarian eating & having a broken foot & diabetes/hypothyroidism, I would gain 10-15 pounds overnight & then it wouldn’t go away. My weight jumped up, and up, and up. It was horrifying. I do have issues with edema and very mild heart & kidney problems – the doctor says nowhere near enough to be the cause of the “idiopathic edema.” On the other hand, it has taken me 6.5 years to lose 65lb eating paleo by default (I have many food allergies) and exercising at a moderate to vigorous pace for 2 hours a day on average. I have determined, through vigilant tracking and weighing of food over years, that my metabolism, with thyroid medicine, is that of a person my size in a coma + any sweaty exercise done. Walking, housework, standing all day… none of that counts. I feel better when I am active all day long, but I don’t lose any weight or appear to burn any extra calories. My theory is my body just downregulates my metabolism, something it can’t do with the sweaty exercise. I have also learned that it takes 3-6 months to see the full effects of any calorie deficit. So, if it takes me 6 weeks to burn 25 pounds, it will be 3-6 months of watching my weight zig-zag in a downward trend to get there.

      I’m researching faster weight loss to try to amp myself up for yet another attempt at turbo-mode. The weight loss delay effect I experience, which I get is likely a water retention issue, makes this entire process exhausting and disheartening. I have been eating healthy, whole foods since 1999 & exercising daily since 2009. I’m tired of people being surprised and accusatory about my lifestyle habits due to my weight. Anyway, enough whining. LOL.

      1. Hi Michele, I’ve been insulin resistant for 10 years and no doctor has been taking my condition seriously or has tried to help me. I recently saw another specialist about it and they’re checking now if I’ve become diabetic by this point.

        The reason I felt like replying to your post (albeit it’s almost a year ago) is that I was powerless to my weight creeping up despite a healthy low carb diet. I’ve been so devasted following everything to a T, dreading social events cause you have to explain why you don’t eat pizza or booze … while staying 30 pounds overweight. I’m also very sporty and work out regularly several days a week.

        Everything changed when I came across Dr Jason Fung’s website where he explains why you can’t lose weight as an insulin resistant person on a low calorie diet.

        To make it short, he recommends fasting, both intermittend and longer ones to diabetic and insulin resistant (IR) people cause it is the best way to get your insulin levels down and reverse IR. He explains very well why fasting raises basal metabolic rate and why low calorie diets wreck your BMR.
        I’ve tried daily 24 hour fasts for weeks but had to realize my IR is too strong and I had to extend the fasts. So 8 days ago I jumped in and the deep end and started my first water fast. Due to a ketogenic diet and 24 hour fasting prior to the fast I’ve not once been really hungry. The real challenge I find is that the reward center in my brain is throwing regular tantrums and it makes you think of how how big a role rewarding ourselves with food/shopping etc plays in our lifes.
        Due to Dr Fung’s advise I also stopped drinking anything containing artificial sweeteners cause they might also spike your insulin.

        In one week my weight has gone down 11 pounds. Obviously half of it will be water. In case you’re giving fasting a try I’d recommend staying active. Contrary to what many people say I don’t feel more energetic than before : )
        But once you start walking you soon feel much better. I’m trying to get the best results out of my fasting by walking 2-3 hours a day.
        I know I will gain some weight back but I’m also positive that I’m able to maintain it because of my already healthy primal way of eating. Right now my plan is to finish this 14 day fast, then go back to eating primal and alternate some shorter fasts with normal eating phases until I’ll dropped all excess weight.

        Good luck

  8. Born fat? Oooo, an article just for me. Oh wait, that image says BURN fat. Okay…well…still for me. 😉

    1. I first read it that way too. “Born fat” fit me perfectly. 9 pounds, 3 ounces to my 95 pound mother (& no C-section). ?

  9. I have lost 5 in a week doing using two different ways.

    QUALIFICATIONS: I do NOT exercise, thus my 200+lbs. lump of a body. I REALLY hate to exercise. (Give me a pile of wood to chop, but don’t ask me to do a push-up.)

    The first and second time I dropped 5 pounds in a week was attending to my mother as she recovered from knee replacement surgery. I had to climb a flight of stairs at least 10 times a day (that’s 10 up and 10 down). Great workout for a 285 pound guy (at the time).

    The second way took place this last week. I’ve cleaning up my diet, and I’ve been “stuck” at 220lbs. for about 6 months. Last week, I was at 223lbs. and yesterday, I scaled in at 215 pounds. I have been fasting 18-19 hours a day during this time. I’m eating until near full from 9am to 2pm. The foods include, eggs, some meat, kale, bell peppers, a green smoothie, bone broth… Between 4pm and 12 midnight (my lovely work hours as a truck driver), a handful of cashews, a banana, and a low sugar Kind bar. From 1am-9am, I sleep.

    I find on weekends when I “cheat” – mainly at my sister’s homes for holiday visits – I can take the pounds off when I go back to my adopted diet. Homeostasis.

    Mark, I want to thank you all the others in the Paleo community for helping me loose those pounds. I have cut my blood sugar meds and blood pressure meds in half. My biggest triumph is being able to touch my toes again!

  10. I think one of the quite well known bad side effects of rapid weight loss is NAFLD. This is particularly common in gastric bands and can be very unpleasant.

  11. I was mind-boggled with the rapidity of my weight loss a year ago. It is frustrating to see others struggle, following the same path I took. There are differences in how we respond, but whether rapid weight loss, slow weight loss or no weight loss, this is THE healthy way to eat.

  12. I’m so sick of the damned scale. Went primal, lost 60 lbs in 6 months or so. Everything improved, all vitals were up. So I started hitting the gym hard and trying to bulk up. That oh-so-satisfying feeling of dropping weight is a hard thing to shake. I can’t be sure how much muscle I’ve added, maybe 10 pounds in two year or something. Then I slackened my diet a little bit (hello beer!). I noticed my pants feeling a little bit tighter in the waist so I clamped back down on the diet and pants are feeling better. But now I’m terrified of losing muscle. It’s such a difficult balance (of the mind).

  13. This was really interesting — thank you. I haven’t heard of PSMF before, and it made me curious. I’m trying to figure out logistics. PSMF for 2 weeks, then refeed for… 1 day? Then what? Repeat the cycle or switch to regular primal eating?

    1. If you go the Reddit subreddit on PSMF, there are calculators in the sidebar and links to literature. Lyle McDonald’s book, which is available as a free PDF is relied on by many people.

  14. You know, there was always a flag in the back of my mind about the “fact” that rapid weight loss would cause it to come back worse than before. Something just didn’t seem right with that statement. Thanks for the wealth of info, Mark.

  15. Could you please add a comment or two on long term water fasting’s effects to your comparisons. I know intermittent fasting has been covered well in previous articles.

    1. Not sure what you mean by “long term” water fasting, but it sounds to me like you’re talking starvation. Not a good idea at all.

      1. You’re essentially right. I’ve heard of people doing a water-only fast for up to 21 days. Sounds incredibly dangerous.

  16. Just the type of information I have come to count on, objective, insightful and concise. Very helpful, thank you.

  17. I have some extra weight I need to start getting rid of. In the past I have shed pounds pretty easily by cutting carbs. I’m concerned about loosing weight too quickly and ending up with extra/loose skin as I’ve seen this being a problem for others. I had significant weight gain during my last pregnancy (5 years ago) and weigh more than I ever have. Doesn’t quick weight loss make it more likely that I’ll end up with loose skin?

    1. I talked to a guy at my gym a few weeks ago about the loose skin issue. He’s a very well respected plastic surgeon who said he does about one skin removal surgery a week. Depending on how big you are and your age, it may or may not be an issue. He says our skin is very resilient and up to age 40 he says most peoples skin will tighten back up. After 40, it starts to lose elasticity. Obviously people who are 600 lbs will have more of an issue than someone who is 300 lbs. if you’re just talking pregnancy weight, I assume you’re prob less than 40, so you should be fine, even with rapid weight loss. It may take time but your skin can tighten up. Drink water and exercise to firm up, during and after the weight loss.

    2. I’ve “heard”, for whatever that’s worth, that loose skin depends a lot on how fast the weight went on, not how fast you lose it. Double check, that, though.

  18. I can’t believe that after 14 years of “The Biggest Loser” someone on that show hasn’t performed and published something. Dr. H (from the show) has some strong opinions about grossly obese and their weight loss. I don’t understand why he hasn’t some some formal studies. Granted, the show isn’t ‘normal’, but still.

    1. The last I saw was that a majority of the contestants from The Biggest Loser gained back the weight. And season 3 winner Eric Chopin went from from 407 to 193 down 214 pounds in 8 weeks but the last I heard he was back up 175 pounds to around 368.
      Not sure where he’s at now though

  19. One of the best articles on here. Weight loss is easy but it’s losing the right kind of weight and long term, not 6 weeks from now but years down the road.I assume when people say they want to lose weight is that they want to lose body fat. Like mentioned with dehydration, losing water weight can happen quickly but tends to return quickly.
    Probably goes without saying that using a scale is not going to indicate what type of weight loss is happening as there’s no indicator of loss from water, body fat, muscle etc.
    With my clients I teach them to go by measurements to get a good indicator of progress as opposed to scale weight. You may be only a few pounds lower but when you’re clothes are a lot looser you know you’ve been making positive body changes.

    1. Thank you for your thoughts on this–it was refreshing to see someone suggest forgetting the scale and focusing more on measurements. I’ve only lost 6 pounds so far (2 weeks in, 6 pounds first week, 0 the second week) and I’m scared to get back on the scale on Monday. Week 3 is when I give up if I don’t lose anything more. This time, however, my clothes are definitely fitting better and I know I’m losing, just not sure why the scale doesn’t show that. After reading your post, I am going to focus on measurements and see how that goes. Thanks!

  20. I think it is interesting the above comments of those who drop alot of weight easily going primal are from men and the folk who struggle to lose are older women. (At least from what I can tell by obviously male and female names). I am struggling to loose on a clean primal diet as a menopausal female…basically eating what I did 4 years ago and was able to maintain with, but now I gain weight. Too much fat (love those macadamia nuts!) and my blood sugars and cholesterol are now getting dangerously high.

    Perhaps a reboot of PSMF is in order for two weeks. anyhow, it is interesting to experiment with different macronutrient ratios and calories to find my new normal. A fun if somewhat challenging journey. A dose of patience helps too.

    1. I am 48 and I lost 50 lbs last year in about a 5 month span. I too struggled for two years trying to figure out what was going on and why I was gaining weight. I also had blood sugar issues which I watch closely. I have been low carb for years but I removed the dairy for a week and my weight started falling off. I was using heavy whipping cream in my coffee and it was really hard to give it up. Heavy whipping cream does not work for me even though many ketogenic diets promote it. This probably does not speak to everyone, but I find I can have little dairy and it is in the form of butter and some cream cheese and once in a while a hard cheese. But I do not eat near what I used to of dairy products and I have kept it off for about 6 months now.

    2. I agree, I’ve read many a post here and elsewhere mainly from men saying ‘weight loss is easy’. Said no woman ever!

      I’ve been primal eater for about 4 years and despite initial weight loss, the past 3 years of low-carb, high-fat (even bouts of VLC) had the scales stalled. I haven’t touched processed food in years, I do weight training, HIIT and yoga. I walk everywhere, sleep great and practise IF, eating in my 8 hour window about 4 days week. I feel great, but the weight just wouldn’t budge. Bouts of VLC were terrible, I don’t know how people live on keto, each to their own, but i felt like a zombie.

      Then I read The Perfect Health Diet that suggested adjusting my macros to include safe starches and reduce added fat to include those found in foods (oily fish, red meat, avocado, offal etc.). It’s so contrary to typical paleo advice mostly offered by men that LCHF is the only way to lose weight (Jimmy Moore, Dave Asprey etc.).

      For 3 years with fat at 50-60%, I now have relatively even macro split and after 2 short weeks I lost 2.7kgs. The scale finally moved. Also my hair stopped falling out in clumps and my mood improved immediately. The clouds lifted from around my head. I feel amazing!

      I wanted to share this because I’ve been reading forums for oodones, and barely find any advice that reducing fat and increasing good carbs (to around 75-100g) can actually help women lose weight. N=1 of course, but if you’re a women like me around 40, perhaps balancing your macros may help shift the scales in the right direction. Good luck!

  21. Thanks for this! The first time I tried Paleo/Primal it worked super well. I fell off the wagon and since then have been trying to get back on with limited success. Reading your article I realized that what I did the first time was essentially a PSMF – all meat for a week. That probably helped jump-start my transition – both in weight loss and in paleo (because at that point I was SO happy to have veggies again). I think I’m going to try that again because I’ve been having trouble staying to the diet and I don’t feel like the weight is coming off.

  22. I think this article can be misleading because rapid weight loss is addicting. Regardless of whether or not you are losing fat or muscle, it feels good to watch the number go down on the scale and ignore the signs that something is wrong. Psychologically, rapid weight loss is dangerous and can lead to eating disorders. It is addicting.

    I speak from personal experience. I felt great when I lost over 25lbs in one month, and had never felt fitter. What I didn’t realize was the damage I did to my body. I was not too thin, but my sport required a muscular figure, over a lean track runners. I became bulimic, and for three years I struggled with amenorrhea, irregular heart beats, and other symptoms that led me the hospital room.

    I have now gained the weight back and more, have regained my period and muscle, and on my way back to losing weight slowly, 1 lbs a week. I think this article doesn’t address the difference between male/female physiology which makes it easier for men to lose weight rapidly compared to women.

    1. I agree that this is an area where there are big differences between men and women. And big differences between women of childbearing age and post-menopausal women. Also children and teens, especially female teens.

      I found a book that had some of the answers (but not all):
      ‘Why Women Need Fat: How “Healthy” Food Makes Us Gain Excess Weight and the Surprising Solution to Losing It Forever’.

      Also, Stefani Ruper’s blog (Paleo for Women) is well researched, but only relevant for adult, pre-menopausal women.

  23. Mark, this post has a couple of references to things I’ve been looking for in the Primal concept. One is the gallbladder. I’ve seen several references to what may be good or bad for it, but what if its been removed? Also you mention the Elderly, which is somewhat subjective. At 80 I must be approaching that status. Are there other octogenarians on board who might comment?

  24. How interesting that conventional wisdom is wrong yet again. I wonder why all the “experts” tell us to lose it slowly? Perhaps that’s how people lose weight on low fat high carb diets. (yes, some people do lose weight on these). I really appreciate the work Mark did to read the studies and report on them.

    One of my friends successfully followed the Dukan diet, which got a lot of bad press in the low carb community for being too low fat. From my friend’s description, it sounds like a PSMF diet.

    I’m a middle-aged, obese woman with a boring, stressful job trying to raise kids, help aging parents and balance it all. I’ve been 100 lbs over weight for 20 years. (Thanks low fat diet!) Over the last couple of years I have put on about 40 lbs more. UGH! I have no motivation to exercise. I think the motivation to stick to the diet ebbs and flows with my monthly cycle. I have read way too much about health for 20 years. Knowing and doing are two different things.

    I’ve been thinking that if I could just lose 5lbs a month, keep it off and then move to the next month, it wouldn’t be so overwhelming. It’s not a sexy idea. I’ve been through the dieting hope cycle hundreds of times.

    1. Valerie, have you actually tried a Paleo diet? I know that sounds like a dumb question since you’re commenting on this website, but it sounds to me like you’re definitely a “knower” and not a “doer.” It also sounds like you could write pages and pages of “Yes, buts” that you’ve chosen to apply to yourself. (Yes, but I have a boring job…but I have kids…but I bought into low-fat…but I don’t exercise… )

      I don’t mean for this to sound unkind, but you need to stop shooting yourself down. You sound threatened by the very idea of losing weight–and to be honest, I seriously doubt that your idea of losing 5# a month would ever work.

      Since you’re here, you probably already know the drill, particularly if you’ve read some of the amazing success stories Mark publishes. That’s half the battle. The next step is to convince yourself that you’re worth it. Thirdly, just do it. Paleo/Primal is about the most effortless, delicious way there is to lose weight, but I’m not going to lie to you. It does take a certain amount of willpower and a whole lot of desire.

      The good news is that exercise isn’t necessary in order to lose weight. I lost 20 pounds with a torn meniscus that kept me parked on my rear. Eventually, as you lose more you will naturally want to do more.

      1. I know this is old, but I was reading through the comments and the statement, “The next step is to convince yourself that you’re worth it” hit me hard – it brought tears to my eyes. This is my problem. I don’t feel like I deserve to be healthy and happy with my body. I feel guilty and tell myself I should be spending that time on taking care of my family instead of me. I have all of the information I need to get rid of the weight, but I have yet to believe that I’m worth it. I enjoy this site and I wish I would use the wealth of information available here.

        1. SuzyQ, thanks for your honesty. And, let me tell you, you’re not alone in this. Many people get stuck on this part because of long-held beliefs about themselves and/or present circumstances. Your family will benefit from seeing you take care of yourself, but I know it’s not easy to make that jump. Know that you can make a choice at a time – maybe one good thing a day just for you. Grok on and thanks for being here. – M

    2. As I understand it, you don’t have to exercise to lose weight. Exercise can boost your appetite which can undermine the weight loss effort. Also, at your weight and age (saying this as a 44 yo who used to be 90 lbs heavier) do your joints a favor and consider a very low impact routine such as walking with maybe some bursts of power walking and some bodyweight exercises that you start in a modified position and work up to the full exercise.. Exercise is good for you but its wise to ramp up slowly to avoid injury not to mention to avoid hating it. 75% of this thing, though, is going to be what you eat.

  25. I will make 60 this year, been fat my entire life. I weigh 263 at 5’11”. A month ago I was about 280. My knees are shot, hips and back are screaming. The article by the gentleman in the Navy is my story, 5 years active and 21 years reserve. Always borderline, always on the edge of being thrown out because of weight. I have lost many pounds many times rapidly and for a point in time, weigh-in and tape. I always creep back up. I am sedentary, sit at a computer, drink water for exercise (so I have to get and go to the bathroom). Walking is a major chore, I try and get in 1/2 hour 5 days a week. At this point I don’t care if I lose muscle or fat I want to lose weight. I eat veggies and meat, coffee for breakfast, no sugar except apple orange or grapefruit, no starch or dairy, avoid food, constantly hungry, always packing food, phobic about running out (I have two MRE’s behind the seat, never open them but I have them). If I do anything (walk, ride bike, get firewood, on my feet in the shop) I ache for days. 2 Advil a day keeps me moving. I fast every 3rd day for about 20 hours. Sorry for the long diatribe but many years of reading this site and trying to implement, I am still fat, sore, aching and getting older. This article is excellent as to going over reasonable weight loss. Comments show that older is harder to lose weight. Diet AND exercise is required. What is reasonable for a 60 year old, fat, sedentaryduetojob, achy guy when it comes to exercise? Could you please direct me to resources for those of us that are older? I am not aging well, my mind is still in the 30’s as to what is expected, my body disagrees and says so with pain. 80 pounds overweight is really hard on the old frame. Very Frustrated.

    1. I found after I ditched the carbs in the primal diet, my health returned. I’ve done several variations of primal since. During this period of experimentation, I discovered I was intolerant to gluten, wheat, dairy and deadly nightshades (potatoes, chilli, capsicums/peppers and tomatoes). This is why I would sometimes lose weight on Paleo and other times it didn’t seem to make much of a difference.

      It was these other foods which would throw me out, which are quite acceptable on the paleo diet. I probably eat more carbs than I should, but at least they’re not laced with gluten and wheat. I had to be very strict reading the labels on canned and packet foods.

      It seems like a lot of effort to go to, but its the only way I can get my health back, look after kids and be happy in my marriage. The other way is to experience debilitating pain that doesn’t make me want to do very much.

    2. I am not in your situation so cannot offer any specific advice. However I would suggest you check out the forum. Use the google search box to find threads that might fit your situation. You should be able to read relevant threads without joining, but you’ll need to join if you want to comment or, better yet, start your own thread. Hopefully other commenters will chime in with their ideas. Good luck to you.

    3. I can see how that would be super frustrating! Swimming might be something to consider and/or aqua-aerobics. I’ve even seen equipment you can buy to use in the pool to boost resistance. Not saying to start with that but it’s option for down the road. Otherwise, maybe cycling (recumbent or upright) or an elliptical trainer which are both low impact. Look into quercetin supplements (anti-inflammatory found in celery and onions, for example.), turmeric, and fish oil to help with inflammation. It’s not a bad idea to eat a lot of onions and garlic as they are anti inflammatory foods. I know someone aged 55 who says tart cherry juice was helpful for him to continue running. Consider having a doctor run a food sensitivity test to see if you are allergic or intolerant of anything you are currently eating. Sometimes, that can aggravate inflammatory conditions like arthritis. Good luck and hang in there!

      1. Other good anti-inflammatory supplements I forgot to mention: ginger, astaxanthin, boswellia, and bromelain. I also recently read but know little about the K-laser Class 4 laser therapy for treating inflammation and injuries. Something to look into. Try googling that with “Dr. Mercola”.

  26. You know what annoys me (rhetorical question) is when people say that primal eating is too restrictive. Really? I’ve been between 176-192 for about 4 years. When I get up around 190 I panic, lose about 10 pounds and gradually gain it back.

    I’ve been able to do it with a multitude of “diets” and strategies. This time around, I went primal and oh my goodness I am so glad I did. The weight came off without the suffering.

    Now when I say primal, it’s not even strict primal. It’s primal for breakfast and lunch, but if my wife makes a non-primal meal for dinner (I have 5 kids and I’m not going to stick my nose in the air at her chili or quinoa or brown rice) I’m going to eat it.

    In short, I went to a wedding reception, passed on the cake (as far as I know, no weight loss program involves eating cake) and filled up on fish and vegetables and some prime rib.

    Restrictive? Not really.

    The great thing is, this type of eating is sustainable, which hopefully means I won’t have to panic at 190 again.

  27. Hi Mark,
    How do you feel about the Hcg (VLCD) Diet, for those that only want to loose 10 to 15lbs?

    1. Just an anecdote, but I did HCG and lost 25 lb in a month (5’5″ woman, started near 175/ size 12 and ended at 150/ size 8), and I did this while going to Crossfit 3x a week. My friend, one of the trainers, would ask me at every 6 AM class, “You’re not going to faint on me, right?”

      It felt AMAZING to lose a pound a day. It felt equally as annoying to eat 500 calories a day and chug water and tea for all I was worth.

      Here’s the sad part. I lost strength while I was on that diet, and gained back all the fat + a few lb in 6 months. I’m only one woman, and perhaps it’s possible to maintain HCG weight-loss afterwards, but a friend also had the same results (she lost less weight but gained it all back).

      This time I am in it for the long haul. I’m doing carb cycling (low carb in AM, highest carbs at night post workout) and less fat than before. I also cut the cream in my coffee down to 1 tbs.

      I also added in a day of boxing and a day of yoga, and cut one of my O-lifting days so now I do that 3x/week.

      I’ve lost 8 lb since Christmas (175-6 lb down to 167 as of yesterday) and still have 17-ish to go.

      Good luck, whatever your decision is! 🙂

      1. Hi Mel,
        I have been scrolling down to see if anyone would mention that diet. I have done one minimum round of HCG, after 4 years of gluten free/primal I suddenly (over a period of about 3 months) succumbed to fibromyalgia, weight gain, alarming hypertension, and elevated cholesterol. It was scary.
        On the diet, (21 days)I felt fantastic, no hunger, the pain went, the blood pressure normalised, and I felt like my body was drawing breath. It also gave me the headspace to think about what I had allowed to creep into my diet and life. 3 weeks after finishing the minimum course I realised via blood tests that my thyroid is low, testosterone and progesterone are low, and my vit d had crashed. This wasn’t due to the diet but it did impact on the diet in that I plateaued at 6 kgs, but I have lost a further two kilos in the last three weeks of stabilisation. For me I think the thyroid problems have been long term, and I am now addressing these and the other hormonal imbalances. I will test before doing another round, to take maximum advantage of the hcg.
        It is a diet that requires commitment, it’s boring but it is temporary. After the hcg stops it’s back to a simple low carb, moderate fat and protein diet, which I am really enjoying. Better yet the weight has been shed from the waist, upper arms, hips and thighs. Every girls dream.
        Because I was in pain I didn’t exercise during the hcg diet phase, and I am only just getting back to it. The original author of the diet doesn’t recommend vigorous exercise during the calorie restriction phase.
        To all those struggling, check hormones that impact the thyroid, the hypothalamus and in women the over all balance. For me this has been the saboteur of my health for decades. It is very frustrating,

    2. Hey Tammy, I echo Mel’s experience with HcG. So similar to my own.

      Let me start by saying that I wouldn’t recommend it. I did two 6 week rounds with the required maintenance period in between. I lost 18kgs overall and that alone can be very empowering. BUT. It was an extremely isolating and unnecessarily restrictive diet protocol (IMO).

      I gained all the weight back after round 2. Waited 6 months and attempted round 3. I only lost 1kg eating 350 cal per day in 6 weeks. That tells you a lot I think about how devastating it can be to your metabolism.

      I researched PubMed to find any studies worth their salt on HcG. Interestingly, aside from observational studies portrayed in pounds and inches in the 50’s, most of the studies were in the 70’s and 90’s. Northing more recent. Nothing that supports not combining vegetables (a complete joke). A respected 1995 study based on two control groups (one taking oral Hcg and another a placebo), found the exact same weight loss results. HcG is a myth. You’re just starving yourself. It’s a great gimmick that brainwashes participants into believing it’s more than just VLC diet.

      Having been through 3 rounds, I would say there are much better ways to lose weight that retains your sanity. The daily weigh-ins can really impact your psyche. It becomes your whole world. Not a good thing.

      I would recommend (and where I had success after years of LCHF paleo to recover my metabolism) trying primal with a balanced macro ratio, reduce your fat intake to those found naturally in foods (oily fish, offal, avocado and meats). Read Paul Jaminet’s blog The Perfect Health Diet. He recommends minimum calories for weight loss while still being nourished. When you reach your goal, you don’t change your diet much, simply add back in your healthy fats to remove the temporary calorie deficit. So simple, so easy. You’re not hungry, you have abundant energy, you can eat out and socialise, you can enjoy life’s simple pleasures here and there (e.g. Dark chocolate, wine etc.) without guilt and still successfully continue to lose weight. Well that’s been my experience. Please do rethink the HcG quick fix. I sincerely regret ever doing it.

      Good luck with your journey.

  28. Interesting! At age 56 I discovered I had reactive hypoglycemia and a high fasting glucose. (Easy to test at home with a glucose meter and internet instructions.) I started a low-carb paleo diet immediately, and my husband joined. I’m 5’4″ and weighed 130; I was only a couple pounds above my “real” weight of 124. My husband dropped about a pound a week right away; I lost only 2 pounds in 2 months! At Christmas I got sick and dropped to 122; since then my weight moved back up to 124 and stabilized. My fasting sugar went from 118 to 78–that’s a 40-point decrease! No more hypoglycemia symptoms, as long as I stay ketogenic, drink very little alcohol (no spirits ever), and consume enough fat. Buttered cheese, anyone?

  29. Great to have a review of rapid weight loss diets and well researched as usual! While my Low carb high healthy fat lifestyle (I refuse to call it a diet), not counting calories and relearning the ability to recognise when I am full resulted in a 22 pound loss it was over a 9 month period. However, I’ve pretty much maintained this for the past six months.
    Best of all I was & still continue to never feel ravenously hungry so never felt I was missing out. I’ve also not felt the need to stray to any great extent but add some realism if I do. So I dont kill myself with guilt if a French fry jumps into my mouth every now and again!

  30. I am 52 and went Primal on Sept 22, 2014. So far I have lost 31 pounds & feel great! I do not play as much as I need to, but frankly it is just too cold in Alaska right now for me. I expect to lose more when I resume hiking this Spring.
    I have lost more weight faster at 52 by following Mark Sisson than I did at 40 on Weight Watchers. I never plan on leaving the Primal lifestyle and I am healthier than I have been since my 30’s.

  31. it took me a year to lose just a titch over 100lbs.

    the first 50 came off in 4 months. the next 50ish took the other 8 months.

    side note: i keep meaning to send in my success story to MDA, but i keep getting distracted by life.

  32. I had more success than I could imagine, 120 lbs in a year and half. Mine was actually slow and steady. But that was me and how I approached things.

    I ended up not doing a Whole 90 or 21-day PB challenge way. Mostly because I didn’t know about them. I was kind of learning and doing all at once.

    I also had my share of lifelong treats the first few months. But what happened was I focused on change goals not weight goals and absolutely not weight goals and time.

    I frankly didn’t have weight goals themselves, I had health goals.

    It turned out my weight loss was like a metronome for the first 100lbs or so. 8 to 12 lbs a month, month after month for a year. It slowed down for the last 20. Which makes sense since I was much closer to ideal.

    Dial in healthy eating and then healthy living (sleep, exercise, etc.). The weight takes care of itself in whatever time frame it will. At least that was my experience.

  33. WOW! so inspiring to read all the success here! I wish i could say the same. still battling my fatty liver. my Dr . is on board with my primal eating. I have tried all combinations of fasting ,carb re feeding etc, . still cannot effectively maintain any weight loss. stuck at 230ish.I am 5’10 ! was down ten lbs, thought I was on my way, but it came back. going for labs this week, hoping to see if my liver has improved , and going to look into any thyroid issues. but I do like to read how people do and achieve, gives me hope anyway!

    1. you should check out Chris Masterjohn’s blog! he has a lot of great articles on fatty liver and the importance of dietary choline for maintaining liver health.

      1. wiil check that out! i am currently on choline and milk doctor wants to see if I get a positive reaction after 6 weeks being on it, take it from here!

  34. Fantastic article that combines a lot of good information! I’ve seen all of it, but only after years of poking around and reading up on stuff. I’m surprised that intermittent fasting didn’t get a paragraph. I’ve used a couple 24 hour fasts per week with good results to shed some weight quickly, but honestly haven’t needed it since going primal… 🙂

  35. Hav you ever watched Naked And Afraid on Discovery? They go pure primal for 3 weeks (many don’t make it). The woman lose an average of 18 pounds and the guys average about 25 pounds. That’s eating from the fat of the land and mostly starving and being semi-dehydrated the whole time.

  36. I’ve been following a fairly low-carb diet for about 7 months now. I’ve lost a total of about 22 lbs so far. I have not been exercising. I hope to lose another 30 lbs during this year of 2015, if I can. I will continue to do low-carb and fairly low-calorie.

  37. It gives me hope when I see perimenopausal woman having positive weight loss success. I wish the weight would fall off but I am definitely not one of those types. I used to be when I was younger. I yoyo’d for years and I think it really impacted me in the long run and now every pound is well earned. But I feel SO much better physically being low carb that I don’t ever want to go back. Honestly I think I would be full blown diabetic in less than a year if I ate like “normal” people do. Which is not so normal or healthy. So I will plug along at slow slow slow and steady.

    1. I guess I am perimenopausal at age 52. I’ve had slow success at losing weight with low-carb, low-calorie eating.

  38. Are there any considerations for loss rate with people who were exposed to toxins while gaining the weight?

    We have a relative (now deceased from other causes) who was apparently exposed to Agent Orange a lot during the Vietnam war. His ex-wife (a nurse) noticed that every time he lost weight his (what we now call PTSD) symptoms got worse. Her theory was that metabolizing the fat stores was also mobilizing old stored toxins.

    If there’s anything to this, anyone similarly situated (aerial applicators, for example), might want to moderate the mass mitigation if distressing side effects arise.

  39. I’m 62 and weighed 240 when I switched to Primal/Paleo. I lost 20 pounds in 10 weeks while doing crossfit (lifting weights and cardio).

    I took a break over Thanksgiving and Christmas and only gained 2 pounds back.

    I then started another campaign of strictly primal/paleo. and have lost 12 pounds in 3 weeks so far. It seems that if I don’t eat enough for basic maintenance, my body thinks I’m in starvation mode, so it becomes harder for me to lose weight. But if I eat 1500-1900 calories per day, and keep the carbs in the Primal Sweet spot of 50 – 100 carbs per day, and exercise at least 3 times per week, I continue to lose weight.

    Primal works for me. I’ve lost more weight eating animal protein and increasing my fat intake (from nuts, seeds, olive oil and avocado) than by trying to be vegetarian and eating beans, grains, and vegetables and doing just cardio work. Of course, crossfit helps a lot too. I am much stronger now that I’m lifting weights and eating primal.

    Thanks, Mark.

  40. I am just starting week 3 of the primal challenge and I have dropped 15 pounds the first 2 weeks. Losing the weight quickly has definitely inspired me to stay on track.

  41. Does anyone have suggestions for losing weight for a person who’s already smaller? I think I should be able to talk about this within this community, but I tend not to be able to have these conversations in general public because comparatively I’m smaller than most.

    Basically, I’m 5’1″. I was about 122 in high school which seemed somewhat large then because all of the other girls around me weighed much less. I didn’t sweat it as much because I was athletic, but I was self conscious about it. Then I went to college and was smaller than most people. I fluctuated between 122 and 128, and in my senior year dropping down to 112 at some point due to stress.

    I’m now in my 30s and hanging out around 128/130. My ideal would be 120 and if I go any lower I start to look quite thin (my ideal used to be to try to shoot for 115 but I began to look sickly and lose shape). My waist has stayed the same inches for most of my life (between 25 and 27 inches). My hips and chest have expanded which I’m guessing is the extra weight…

    I gave all this background because I want to know what no one talks about. How does a smaller person lose weight? I have to take extremely drastic measures to lose even 5 pounds and I’ve always been a person who exercised and ate well. What does that person do? I’ve found it frustrating to see very obese people lose half my weight in a couple of weeks. Or the one who’s 300 pounds who drops down to 110? I feel at a loss. What can a small person do to lose weight and keep it there without having to be extreme? (Note: in my former life, I was on the bodybuilding side of fat burners and CLA supplement, eat every 2 hours, measure your protein, whole grain rice maade me insane world but I was 116)

    1. So following this. I’m 35, 4’11” and 130 currently. Lost some by going very low carb, boot camp, etc. and when I stopped (husband is not on board and will never be, and I work full time so not cooking two meals for dinner_ it came back in less than two months. Now I’m trying to lose some so my dr is happy but it’s so hard on a smaller frame.

  42. This is a great topic and a key reason for most people to try the primal lifestyle. Rapid weight loss is like get rich quick. There is no proven formula for either one. It takes hard work and persistence just to make incremental progress. The 21 day challenge was a test towards a greater commitment to the primal blueprint method. Personally I lost 6-8 lbs and feel in better shape. Looking back, if I completely cut out alcohol, I may have shed 10-12lbs in the three weeks. I could have moved more, eaten better and slept more soundly too. I’m happy with 1-2 lbs per week. Primal movements are now easier and more habitual. I still plan to enjoy a glass or two of wine but not enough to compromise my sleep, will to exercise, or indulge in SAD foods.

  43. After having some initial success going paleo a few years ago I fell off the bandwagon in a bad way. I knew just going paleo wasn’t enough for me so on advice from a few coworkers who have had major success I started Whole 30 on January 12. At 3 weeks in I have lost a total of 9.2 pounds. For me I had to cut the dairy, the “paleo” pancakes, occasional dark chocolate and wine… and just wrap my head around food itself and that it’s simply just fuel for my body. I suspected and learned that I had a food addiction and would “treat” myself with those things for special occasions and/or when I was stressed. I hope to lose about 40 pounds so will continue Whole 30 till I get closer to my goal. By then I hope to have broken my addictions and can then maintain with Paleo and the occasional dairy, dark chocolate, etc. without going overboard.

  44. Having just completed the 21 Day challenge, the 18 pounds I lost during that time leave me feeling full of energy, with increased alertness, and a healthier outlook.

    I get better sleep, and will continue with the living Primal in hopes of ridding myself of an additional 90, or so.

    This is the best I have felt in longer than I can remember.

  45. Yeah for me losing weight has always been like chipping marble, and I’ve only found it to be marginally faster on primal. It’s never “melted” off, as some people seem to have experienced. I feel like for some of us, it just takes a long time to repair your body’s ability to extract the full nutrient load from the foods your eating and become more of a fat burner than sugar craver. It also depends on what just feels better for each person. Going sub 50g of carbs is really hard for me, as I get too caught up in the dogmatics of paleo and perseverate too much on every last detail of what I’m eating (ie feeling guilty for eating a pear). Staying around 100-120g (more or less) feels way less like a diet – more like something I can do longer term. It might not get the fast results, but I’m also not sacrificing my mental health.

  46. I have tried the “Wheatbelly” thing for over a year. Lost the heart burn, diarrhea and slept way better than I have in 20 years, but didn’t lose a single pound after the first three!!! Started at 267lbs and went to 264lbs in the first month and stopped there and stayed there. Slowly the old feeding habits came back and so did some of the wheat, but not all, however the weight didn’t stop coming and now I’m up to 288lbs.

    I need some help. I’ll be 64 in august and don’t want to weigh this much any more. What is the difference between wheatbelly and primal? I want to get down to at least 200lbs so my knees will last a few years longer.

    Will a low carb high protien moderate fat regimen work for me? Help??

  47. It’s true that the low carb, high fat diet has the fastest results and I’ve tried them all. My only obstacle in the weight loss regime is obtaining affordable and easily accessible ‘primal’ food. Cooking my own food is the best way to go but time doesn’t allow me to do it for every meal.

  48. Thanks for the post. A few years ago, the New York Times ran a blog post called something like “Myths of Weight Loss.” One of the myths was that slow weight loss is always the most effective. I posted it on My Fitness Pal, but everyone ignored it.

    I’m technically not overweight, but my weight has been inching up as I get older, and my body fat percentage has increased significantly.

    Going shopping for my PSMF today.

  49. Hey Jerry,
    sounds awesome. that is a lot of my problem is eating. not losing, am 63. cannot even think off cross fit with my arthritis! wow! would you be able to post , for me and average menu. so i can get an idea of food intake for your results. presently don’t eat my first meal until at least 11am- noon. sometimes a little later. that takes me til dinner. it is a large 3egg frittata, 3-4 cups spinach , and broccoli, or brussel sprouts, or cabbage and onions . my go to breakfast, never get tired of it ever! then i am never even hungry at dinner time. this is my real problem. can’t eat enough. will have some fruit , maybe pie of liverwurst ,bite of cheese. my doc want me to ut out the fat to help my liver.chicken , usually for dinner. sometimes a meatloaf, chicken burgers always a steamed veg of some kind. do a carb refeed occasionally like rice and beans,etc still stumped?

  50. I’ve been reading for a while, and starting February 1st I’ve been doing my best to stay Primal with my eating. I cheated several times (I’m a work in progress, of course) but I still lost 10 pounds in one week! And now I’m so glad I stumbled upon this post, because it reaffirms to me that I’m doing what’s best for my body now. I’m so excited!

  51. I don’t understand why you made the comment “as much as 87% of the total weight you lose will be body fat”. The NIH link you point to clearly states a) the 87% number is only a calculation, b) the rule of thumb is an oversimplification and wildly optimistic.

  52. What would be the best approach for the non-obese? I gained about 15 lbs in my mid 40’s, and although many people consider this normal and healthy for someone my age, I always think about the Kitavan women and how their BMIs average around 18 and tend to decrease with age. Would love some thoughts on losing the last few pounds.

  53. I’m 64 years old, 290 and 6’2″. I’ve been fighting these almost 100 lbs for the last 30+ years. I’ve tried weight watchers, fad pills, starvation and exercise and a bunch of other stuff. Until recently my blood pressure has been normal but lately it has started climbing. A year ago I tried the wheat belly routine and had very good “feelings” with it but did not lose an ounce over almost 8 months. I was 267 when starting it and still 267 after 8 months. In the last 6 months gained back up to 290 again and have been there steady for the last 3 months. Bad shoulders and one bad knee from old motorcycle injuries in my 20’s and 30’s, hip pain from carrying all this weight for so long. Exercise is really hard due to so much pain and I over medicated with Ibuprofin a couple of years ago to get me through my last year working and now am very sensitive and can’t take it at all. I’m looking to try this Primal 21 day challenge to see if any weight will come off. It seems to never fail I can lose 25-40 lbs and within a few months it comes right back again. It’s like my empty fat cells won’t allow me to stay slim. I don’t know how much longer I can carry this weight around before I can’t move at all. Any help or advice would be welcome.

  54. No supplement is a replacement for diet or exercise! YES, you will see some weight loss right away by using the Lady Soma Detox, but it will be slow and at a lower level, unless you watch what you are eating. The first time I did the Lady Soma Detox I lost 3 lbs RIGHT AWAY, but then my body got used to it. Now it has been easy to maintain this weight . . .

  55. I was ill about 5 years ago and the weight piled on – nearly 4st (25kgs)…

    Oh – context: I’m a qualified dancing teacher, used to enjoy kickboxing and also strength training. I’m 5’2″ and look less than I weigh (people tell me I “must carry it well”, whatever that means)- but I still definitely weight it.

    …I got so down about it, my doctor put me on Xenical (fat binder-weightloss) for almost 2 years but it was still extremely hard. With this I lost about 12 kgs but it was so difficult, I decided to come off the tablets and with that ‘head start’ (Sep15), I’d continue to do it myself…

    Disaster. I went to work in Australia for 3 weeks in October and put on half a stone (Australians are lovely but they do like to feed you!). Then travelling the country (hotel food is a nightmare) and add Christmas to that (“ooo – cake!”) – nightmare! Sluggish, tired, angry at myself that almost all the weight I took of with Xenical was back on.

    I started ‘almost’ primal (as I confess I have dipped in and out of Mark’s book and cookbook) on 23 Jan at 191lbs. Yesterday (20 Feb) I weighed 179lbs. 12 pounds (5.4kgs) lost in 29 days and as a 44 year old post (surgical) menopausal woman I feel fantastic.

    I am very careful about the amount of carbs I consume (try to keep around the 50g point – using the MyfitnessPal app to check), eating lots of great (protein) food, a little good fat, lots of vegetables, and eggs for breakfast each day – they really do take away the cravings I had and I also have a stash of macadamia nuts just in case I need a quick snack.

    [Oh – I do cheat – I have more alcohol than I should but I now favour wine before beer before spirts under Mark’s advice. Before this I favoured Gin and Slimline Tonic – because it was 56 cals. I never thought about how unhealhy the tonic could be! ]

    I still have a long way to go to get to my desired weight of 128 pounds which is where I (used to) always feel more comfortable and feel more like myself – but I would be more than happy with 135 pounds…

    Thanks Mark, for this great start. I have not ‘specifically’ exercised yet but have so much energy and am finding it easier each day to stick to eating primally. Perhaps after another month I’ll go back to strength training.

    I have never enjoyed a healthy eating plan so much.


  56. I started a ketogenic diet under Drs orders Oct 19, 2015. I’ve lost 90 pounds, very little muscle loss and have been taken off of all BP meds (2), LDL is way down. Just under 40 pounds to go.
    When I saw the Dr in Oct 2015 he told me within 30 days I’d have to start on insulin, that gave me a pretty serious wake up call!
    I have quite a few friends on traditional low fat, high carb, starving till their next meager portion diets, tell me ‘this isn’t healthy’!
    I’ve finally come to terms with ‘this isn’t healthy’, means ‘why is she losing so much weight and I’m so hungry and sweat like a dog everyday and barely lose any weight’!
    I’ll not go back to a ‘traditional’ eating plan, ketosis has too many benefits for me.

  57. Thanks for the article Mark. I’m a dietitian in American Samoa, and I am dealing with this in my work everyday. In school we always learned to promote slow weight loss of 1-2 lbs/week just like you said. I personally think that someone who is 400+ lbs and drinking 6 cans of soda, 3 candy bars, and 3 ramen bowls, and chips all day can easily lose more than 2#/week in a safe way. Just like you said, if you are lean, it probably shouldn’t be done, but if you have 100+ lbs of excess weight, and you cut the crap out of your diet, and add some exercise, you can easily lose weight quickly and safely.

  58. Great article discussing the biochemistry behind why low carb works.

  59. Rapid weight loss works certainly in the short term and improves diabetic markers such as HbA1C. The dangers of too rapid weight loss are the formation of gallstones and the release of toxins stored in fat cells with possible unpleasant symptoms, which is why liver and bowel support are essential. The medically supervised 800 kcal VLCD devised by Dr Roy Taylor of Newcastle University is very successful but in the long term does nothing to address insulin and leptin resistance nor to reset an individual’s weight set point, which in obese people is set too high. The weight comes back on as soon as a normal diet is resumed. The only way to achieve these two long term goals is possibly by remaining on the VLCD until all the excess weight is lost and then through intermittent fasting combined with a fairly low carb diet. This may restore insulin sensitivity, lower the set point and stimulate HGH which itself helps preserve muscle and bone mass. In any case, it makes no sense to assume that the body would start burning muscle during fasting rather than fat once glycogen stores are used up.

  60. Great article. I couldnt shed off some fat because of a slow metabolism. Just found this product and I love the results. Here is the link to the website