Does Carb Cycling Work? It Depends.

The word "CARBS" written in vintage ink stained letterpress type.Keto may not be for everyone, and low-carb is not the only way to eat well, but most would agree that people in the modern world tend to eat way too many carbohydrates—far more than their lifestyles and activity levels warrant. Along with some other big factors, excessive intake of refined carbohydrates is a major player in the modern epidemics of obesity, diabetes, heart disease, and other disorders. This is no longer controversial. Reducing carbs is a good move for most folks.

The majority of my readers are on some kind of low carb diet. Maybe they’re not fully keto. But they all tend to acknowledge the utility of limiting one’s carbs to only those they need. One of the more common questions I receive from this group concerns carb cycling—periodically adding more carbs to an otherwise low-carb diet.

Should it be done? If so, do certain contexts make carb cycling work better or worse?

Let’s have a discussion.

The main reason people here want to introduce additional carbs to their regularly scheduled keto or low carb diets is for the supposed performance benefits. Fat and ketones are great for slower, less intense movements like hiking, jogging, and other endurance activities, the story goes, but you really need glycogen to power intense, anaerobically-demanding pursuits like CrossFit and sprints and powerlifting. Since carbs are the easiest way to replenish muscle glycogen, low-carbers who care about their physical performance need to eat carbs. That’s the conventional wisdom, at least.

Enter the cyclical ketogenic diet, a regimen that promises to let you have your cake (of varying macronutrient ratios depending on whether it’s refeed day) and eat it too. Reap the benefits of keto—improved fat-burning capacity, increased endurance, boundless energy, caloric efficiency, clear-headed cognition—and of carbohydrates—increased power output, fully-stocked glycogen reserves—with none of the downsides.

Does it work?

Formal research is quite limited at the moment. What we have suggests that certain forms of cyclical ketogenic dieting are unnecessary at best and counterproductive at worst.

One recent study actually tested this, pitting ketogenic dieters against cyclical ketogenic dieters for fat loss and exercise performance. The keto dieters stuck to a typical keto diet for the 8 weeks—75% fat, 20% protein, 5% carbs. The cyclical keto dieters were keto 5 days a week and spent 2 days refeeding on carbs. Throughout the study, both groups lifted weights 3 times a week and did high intensity interval training (HIIT) twice a week. When the 8 weeks were up, they ran some body composition and performance tests.

What happened?

There were no differences in performance. All those carbs—16 days of carb refeeds—weren’t enough to help the cyclical keto dieters perform any better in the gym than the keto dieters. And this was strength training and HIIT, which are supposed to require carbs for optimal performance.

There were differences in body composition. The keto group lost more body fat and didn’t lose any lean mass. The cyclical keto group lost less body fat and significant amounts of lean mass. You can’t get any more stark than that: Keto was way better for body composition.

My takeaways?

I see a lot wrong with the 2-day refeed approach. For one, these subjects were trying to adapt to keto. They weren’t experienced. Right off the bat, that’s a lot of time to be gorging on carbs while ostensibly trying to become keto-adapted. Hard to make good adaptations when you’re doing 2 days of high carb every week. One step forward, two steps back. 

I imagine “targeted keto”—eating small boluses of carbs before/after training—would work better than 2 day refeeds. Hopefully, research into that type of carb cycling is coming.

These guys were training pretty hard, and pretty Primally: 3x a week lifting, 2x a week HIIT. It seems like basic strength training isn’t glycogen-dependent enough to warrant 2 day carb feeds. Seems HIIT isn’t either, though I didn’t catch the exact protocol.

They also did a followup with the same groups where they reintroduced carbs in two ways. One group slowly introduced carbs, little by little, eating 1 grams per kilogram of bodyweight per day. The other group just went whole hog, eating 3 grams of carbs per kilogram of bodyweight each day. The former group gained little to no fat, and was even able to put on lean mass. The whole hog group gained more fat and failed to gain lean mass. To me, this supports the notion of small targeted doses of carbs when refeeding, rather than massive binges.

Other studies find that for strength training—basic moderate volume lifting—keto is great. You need some initial glycogen to help with the lifts, but you don’t need to constantly refill it. Besides, and many people forget this, you still have glycogen on keto. You still refill it on keto, just more slowly. Doing something like CrossFit four days a week probably works better with some carbs because it’s so glycogen-dependent and you’ll need quicker repletion. Yet, even CrossFit WODs are doable on keto, provided you give your body enough time in between sessions to recover.

What about gains? Don’t we need carbs to build muscle? Studies show that the insulinogenic effect of protein alone is adequate for post-workout muscle protein synthesis. Adding carbs doesn’t augment the effect. And research on full-blown ketogenic trainees shows they can effectively gain muscle.

Another reason people wonder about carb-cycling is to overcome fat loss plateaus. There’s some truth to this, as I discussed several years ago in a post on carb refeeds and weight loss.

Spending too long a time in a low-carb, calorie-reduced state can reduce leptin, a hormone that regulates energy expenditure. Low leptin, low energy expenditure, higher appetite, harder weight loss.

A short carb refeed can boost flagging leptin levels enough to spur additional fat loss.

But as the previous study shows, carb refeeds won’t improve your body composition (they’ll actually worsen it) unless you’re already fat-adapted. I’d go one further and say carb refeeds won’t help you lose fat unless you’re fairly lean. They’re better for the person battling those last few stubborn pounds than they are for the obese person just beginning their weight loss journey.

If you still want to carb cycle, heed these suggestions:

  1. Make sure you need the carbs. You should be doing serious glycolytic work that depletes muscle glycogen on a regular and frequent basis. Think CrossFit. Think jiu-jitsu. Think hill sprints for 30 minutes. Lifting and doing sprints might not be enough to require extra carbs.
  2. Do targeted refeeds, rather than free-for-all benders. Consider 20-30 grams of carbs with your workout, not 2 days of bear claws and pizzas. Besides, you can always add more if the initial dose wasn’t enough.
  3. Get adapted first. Don’t get ahead of yourself and shortchange your results. The most scientifically-validated complex carb refeeding scheme won’t do anything if you’ve only been keto for three days. Wait six weeks (at least) to adapt, and then try.
  4. Don’t refeed because you miss French fries. Refeed because you have actual reasons.
  5. Don’t refeed because you’re going through the keto flu and want to alleviate the discomfort. Read my post on the keto flu and push through.
  6. If you’re refeeding to lose body fat, make sure you’re truly on a plateau. “Being on a plateau” assumes you’ve lost significant amounts of weight and are now stuck. It doesn’t refer to those just getting started.

Few people truly need to carb cycle. It can be helpful for certain situations, provided you satisfy the criteria outlined above, but don’t think it’s a requirement for healthy dieting.

It’s nice to have options, though. Hopefully after today’s post you know what your options actually are.

Thanks for reading, everyone. Take care, and be sure to leave your thoughts and reactions down below.

Primal Kitchen Mayo

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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57 thoughts on “Does Carb Cycling Work? It Depends.”

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  1. I had to do a little self-reflecting yesterday regarding my fear of simple carbs. I’ve been free of sugar for quite a while, and as I sat down in the dentist chair for a crown repair the hygienist asked if I’d eaten breakfast. I told her about my fatty coffee and she frowned and said that wouldn’t work as the numbing solution needed glucose to work. She made me drink a box of apple juice! I was horrified when I looked at the ingredient label: 24 grams of carbs and sugar! It was pure sugar! And I didn’t even want it!

    I stewed over the juice box situation all through my dentist appointment. But then, guess what? The juice didn’t kill me. It didn’t cloud my brain, it didn’t make me feel horrible.

    I think I’ve been afraid that having a little bit of sugar would bring back my addiction full force, but it didn’t. I’m grateful for the primal/keto lifestyle and how my body seems primed to tolerate a bit of sugar from time to time, without feeling desperate for more. In my glucose burning days having a bit of sugar would lead to intense obsessive cravings for more and more. That doesn’t seem to be the case anymore. Yay!

    1. Katie, I agree with you. I’ve been primal for so long but having some sugar from time to time doesn’t seem to throw me off too much anymore.

    2. Hmm… I’ve been happily in ketosis for 10 years and redently got novacaine from dentist to cap a chipped tooth. No glucose-loading required!

      1. Same here, Layla and I’ve never been asked by my dental hygienist or dentist if I’ve eaten, nor have I ever heard of needing glucose for the novocaine to take effect!

  2. I do mostly 90/10 Paleo and don’t bother with keto. For me, a “refeed” is occasionally dropping back to 80/20 Paleo and treating myself to a modest increase in (mostly) healthy carbs, such as potatoes and other root veggies, rice, legumes, etc. I’m at a normal weight, but when I was trying to lose a few pounds I found it worked much better to be fairly strict with myself. A two-day refeed every week would have gotten me nowhere. There’s also a mental factor to consider. It’s way too easy to go from two days of “carbing out” to falling off the wagon altogether.

    1. I agree, Shary. For me, a two day refeed every week might make it harder for me to get back on track.

  3. Just my n=1, I thrive well cycling carbs with keto 20-30 g Monday to Friday and weekend refeeds. The benefits I’ve noticed include 1) improved endurance and lifting performance 2) helps regulate hormones – I retain water when eating low carb consistently with my activity level and invariably the refeeds help me drop that water which I assume to be a cortisol effect. I will add that I think some of the benefits are a calorie effect as I struggle to eat enough on weekdays. I also think there is value in not being in ketosis all the time.

  4. I find that eating some oatmeal in the morning suits me well. If i only eat fats, protein, and tubers (in addition to veggies), I find that I often require more calories or am hungry. I don’t see the need to forcibly starve myself. Yes, sure, intermittently I may eat less if traveling or on the road, but otherwise why do it? I fast when I sleep and don’t have any noticeable health issues. Furthermore, whenever I go keto or low carb I ALWAYS feel tired and have hormone issue, feeling under-recovered. That just doesn’t seem appealing.

    1. Yep, this is me too. Primal + oatmeal 3x a week or so. Way to know yourself 🙂

  5. Great article. I’ve been wondering about cycling but more for the hormonal health for us women in our 50s. I’ve seen quite a few hard exercising females mess up their adrenals with keto style diets. Any info would be appreciated.

    1. I agree as well. I am menopausal being doing keto 8+ weeks and no real fat loss but still other benefits, no hunger, mental clarity, less inflammation. I am a Spartan athlete /run and of course workouts still suck as not fat adapted. But lack of fat loss puzzled me at 50-60 gms a day 30 or more of these are fiber. Well I got my head chopped off at another Keto site saying my carbs still too high and I need to lower to lose weight. Because of insulin effect. Well my blood sugars are super, my insulin last tested was a TWO!.HMMM I ate some carbs 2 days ago, feel great had a super workout day after and today AND lost weight! Go figure. We are a different subset us athletic menopausal women trying to just lose our weight gained from menopause. Still researching it. maybe Mark can do a special podcast just for us

    2. Hi ladies, I’ve been in ketosis for over 10 years and I’m now 62. Was personal trainer and yoga instructor for years in my 40’s. Never over-trained and have never regretted it. Now in ketosis I don’t over-do my fitness because it’s not necessary! I hardly have to show up at the gym to stay fit. I believe my blood type 0+ lets me thrive with very few carbs, yet in the winter months I will eat some root vegetables and use coconut flour, with no problems. Fat-burning state is the best thing that ever happened to me. I sometimes take hip-hop classes and can keep up with the 20 yr olds energy-wise for a straight hour. Less is more when it comes to carbs…and exercise!

      1. My point is that if your body is happy in ketosis, it will tell you if/when to eat a few more carbs and even what type. It will also tell you how much exercise is just enough to feel in good shape. No need to measure and analyze stuff, unless you enjoy that! The markers I use are good sleep, stable mood, solid muscle mass, glowing skin, stable energy and stamina, and ability to move fast and lift heavy only when you NEED to (like scoop up your grandkids when they want a hug, run to catch a train, dance class). In ketosis, I don’t have to spend a lot of time “working out” to have all that. (I’m 5’2″ and weigh 104 lbs, no post-menopausal issues, but I also haven’t used alcohol, caffeine, or prescribed or recreational drugs for the past 30 yrs). This way of living works for me, but I don’t believe that everyone should or needs to do what I do. If you stay with it, I believe you will find your own macro-nutrient balance and fitness program that fits you best.

  6. Great topic and one crying out for much additional experimentation.

    My contribution: once fat-adapted, cycling carbs never fails to achieve very low levels of body fat (~5-6%). I’ve done this annually since 2010, having gone through a few months of very low carb in 2009 when I first discovered MDA. I’m now 41. You can see the visible results of this year’s diet at (About section) and judge for yourself whether cycled carbs work. Earlier results can be found by clicking on my name on this post.

    To be clear, my goal with this protocol is extreme reduction in body fat over three months, to set the baseline for the following nine months of maintenance and bulking. It has not proven sustainable throughout the year.

    Improved performance was not the primary objective, although it typically occurred as a side effect. At the end of three of these diets, I competed in powerlifting and set new personal records each time.

    My nutrient split has always been textbook Leangains. Three high-carb low-fat training days, four ketogenic rest days. High protein always (~1.5g/lb scale weight).

    From coaching others, I confirm Mark’s observation that unless significant fat adaptation has already occurred, this protocol does indeed result in excessive wasting.

    My current working hypothesis is that keto should be observed throughout the winter as a seasonal adaptation to improve fat-burning, and that keto is the only time bulking is optimally effective. Bulking on carbs does not work for me; it mostly makes me fat and inflamed. The confusion over “carbs for growth” probably derives from extreme individual differences in insulin sensitivity. Like many of us, I seem to have wrecked any native insulin sensitivity through a lifetime of SAD nutrition up to age 32.

    Note that I have not done the keto calorie-deficit experiment so I can’t say whether that would be more or less effective than cycled carbs.

    However, the anthropological evidence is compelling that paleolithic humans did indeed crank up on carbs through spring and summer, when fruit and honey were in season and daylight hours were longest.

    Even though this is a paleo web site, we often fall prey to biochemical fallacies, justifying anti-paleo behavior like not eating liver, or substituting powders and pills for real food.

    But our most promising hypotheses are always those that are supported both by biochemistry and anthropology.

    And until we personally test a hypothesis, we cannot confirm or refute the results.

    1. What makes things confusing is to read about your particular experience with carbs, only to then read about those who have been doing Zero Carb for years. The zero carbers I’ve met on Twitter for example are weight lifters, runners and competitors from all walks of life. Personally, I’m keto and not zero carb, but it’s intriguing. If you’re on Twitter, check out Sean Baker (MD) and see his record-breaking stats and physique while taking in no carbs at all..

      1. Agreed, there are a number of extraordinarily fit chronic keto dieters. Thanks for the referral to Sean Baker. Luis Villasenor is another great example and has been very-low-carb for several years with no shortage of strength. Certainly his thyroid is not “broken” contrary to one counter-argument.

        Whether cycled carb or permanent very-low-carb is superior can only be settled by n=1 experimentation. For now, I embrace ketosis in winter and cycled carb in summer because

        1) Cycled carb has worked every time I’ve tried it to drop fat while keeping strength, and

        2) All human ancestors outside of the arctic circle certainly consumed fruit and honey when they were in season, so we can be certain of having adaptations to match.

        1. You’re absolutely correct that n=1 experimentation is the key to getting things right for our own particular situation. I’m concerned when I see someone who needs to lose significant weight, has low to moderate activity level or perhaps needs to reverse T2 Diabetes consuming ‘fat bombs’, carb cycling, etc. when it may not be appropriate for their health needs. The plan you’ve developed for yourself sounds more than reasonable and is obviously giving you the results you want..

          1. Very good point that somebody at the start of their journey has very different problems to solve than those who are already athletic and trying to fine-tune performance.

            Our very first priorities should be 1) avoiding toxins and 2) repairing nutrient deficiencies that have been worsening over years, if not decades. That was me several years ago. This means eating plenty of real paleo food and worrying about macro manipulation later.

            What breaks my heart is seeing people newly introduced to paleo filling up on powders, pills, and machine-assisted indoor exercises. This misses the entire point and gives “paleo” a bad rap…

  7. Interesting discussion Mark I’m glad you posted this. I’ve been following a cyclical ketogenic diet since the early 1990s even before Lyle McDonald wrote his book in fact I was doing it before and while he was doing his book and we were all members of the low carb list-serv way back in the day. Then we both played around with BodyOpus via Dan Duchaine. So I’m definitely a vet in regards to a ketogenic diet.

    That being said I was one of the speakers last year in Las Vegas along with Ryan and Jacob Wilson who did that little study you mentioned in this article. In fact they presented it to us before anybody else and they did say that the guys doing the cyclical ketogenic lost of muscle but he said to me and everybody else there that if these guys were adapted he feels that would have never happened so just like any keto study they often don’t allow for adaptation first and that’s why the results are always skewed.

    In addition to the above what I find and many many people that I’ve helped throughout the decades is that on a cyclical ketogenic diet as long as you don’t go overboard eating cake and junk and way over your caloric needs to maintain body fat loss (caloric deficit) you’ll do absolutely fine in fact you’ll find that most CKD’rs never stall…. meaning we never have these hormonal problems just like you outlined; leptin, ghrelin, thyroid, cortisol, etc.

    It’s also pretty fun because you have a date on the calendar when you’re going to have your schedule carbohydrate refeed which believe it or not is not as easy as you would think because it’s a very very low-fat day it’s a very high carbohydrate day and a moderate protein day. This is not donuts and pizza day it’s a specific protocol that must be followed by the book. And the results are for sure worth it.

    Another reason some people do CARB refeeds; some of us use it as more of a reward system for adhering to the diet strictly the prior week or two. For instance if I wasn’t strict leading up to the carb up and did not drop body fat then I did not “earn” my carbs and I don’t get to have a carb day. It forces that need to be super strict in order to be able to give myself that carb day. So in fact it’s a lot harder in my opinion to do a cyclical ketogenic diet than it is a standard ketogenic diet especially trying to control yourself on the carb day which can go crazy and out of control once your insulin levels get out of whack and you want to eat everything in sight.

    I will say though that I do agree with you that the carbohydrates are not needed performance because when we first started doing a cyclical ketogenic diet in the early 1990s just like in the study above we didn’t give enough time for adaptation; so we did 5 days of eating ketogenic and then 1 to 2 days of carbs and we never really adapted but what I found was that we really needed those carbs because we were not keto adapted. So every time we did have carb ups we did feel extra strength in the gym. Fast forward 2 years later where we would go stretches of time months on end without actually a refeed we were fully adapted and then once we started incorporating carbs again we noticed no difference in the gym so that’s why one must be fully adapted before they dabble in a carbohydrate refeed protocol like a cyclical ketogenic diet..

    That being said whether you do a standard ketogenic diet, targeted ketogenic diet, or a cyclical ketogenic diet all three of these will result in fat loss if you’re eating at a caloric deficit there is no magic unfortunately in my beloved ketogenic way of eating 🙂

  8. Did this study only include loss/gains? Long term keto diets can break your thyroid. I found refueling every 5 days with a cup of starch/carb gave me more energy and stamina. Not two days of carbs.

    1. I did not know that about long term keto diets. Would you explain what “break” means in this context and point me towards a citation? Thanks!

    1. I have to agree Wildgrok. All primitive societies ate carbs whether it was tubers or a small amount of grains. They all consumed this with a LOT of fat to basically soak up the fat. Chicken fat on its own is not very tasty but when it is poured over a potato it becomes gorgeous. Groks all over the world ate SOME carbs but nowhere near what is now the norm and ALWAYS ate them with plenty of natural fat. I think this whole topic is becoming a bit nerdy. Find out what works for you and what feels right for your body.

        1. I do mine with Porters and Stouts. Of course I don’t call it a refeed.Every”body” is different, and our taste BUDS reflect that 🙂

    2. I’m with you on that wildgrok, I find myself doing quite a few IPA carb refeeds! How’s it working for you?

      1. It works wonders: if you choose the right IPA you only need one to get the nirvana-bliss-refeed effect, I recently discovered one with 10 degrees of bliss effect (*). But the ones with 8 and 8.4 work very well (grab a 7 if none available at the time in the supermarket)

        (*) alcohol content 🙂

  9. What’s your opinion Mark about this”new” Visual Impact High Carb Fat Loss diet from Rusty Moore and Mark Kislich?…it appears very controversial!

  10. I have followed a one day carb refeed protocol for the last 8 years and 9 weeks ago I decided to drop my carb refeed day and just do a TKD approach, with 20-30g carbs pre workout and sometimes tubers post workout, if my next session is only a few hours apart to the first one. I’m a CrossFit athlete. Im loving the new TKD approach and honestly, I don’t miss my carb refeed day at all!!

  11. Would have been interesting to have a third group with daily (good/smart) carbs (so not low carb per se).
    I think I know which group would have had the best performance for intense workouts… 😉

  12. I tend to listen to my body, “as needed.” I stay quite active and like to pick and choose carbs depending on my day…

  13. I’ve been eating paleo for the past 2 years. Just recently I’ve reintroduced 300gms of white rice into my diet daily, mixed into steamed vegetables, salads etc. I’ve found my energy levels a lot better considering I do a fairly physical job. It’s really helped. Do you see a problem with doing this?

    1. FWIW
      If it is working for you – I see no problem with it. We all have different goals/lifestyles/bodies/brains. I personally think N=1 is the only reliable way to gauge a result when I make a change.

  14. Interesting post. I talked to someone recently who carb cycled and seemed pretty miserable. It sounded like a lot of work to track everything. I’ve been fat adapted for years now and feel great, but there are still days when I eat more carbs. Never processed carbs…just not worth it. But totally cool with some sweet potatoes or even a small portion the lentil pasta every now and then. Or some really good chocolate. I always do it later in the day. Should also mention that I definitely notice more of a craving for carbs when I’m sleep deprived (which happens when my dog needs an early walk after a late night of bartending.)

  15. This post reinforces my belief that the only times to eat carbs are before, during, or after exercise.

  16. Fascinating stuff and read everyone’s posts, really thought provoking and some experts supplementing Mark’s great offering as well as past success story folks with a great perspective. I’ve posted similar thoughts in the recent past, but again … here we go … when you read about the long-lived Blue Zone people they have a natural, unforced lifestyle that involves lots of movement, fresh air and sunshine, good sleep, a relatively stress free life with gratitude and purpose, lifting things when needed, gardening (often growing their own vegetables and herbs and fermenting food), lots of social and family activity, and primarily a plant based Mediterranean type of diet with ample healthy fats and some meat here and there. They do NOT count calories, go on keto diets, or do crossfit LOL. Just something to think about as we obsess in our n=1 experimentation. All the best to everyone. 🙂 – George

  17. I am a big advocate of the ketogenic diet as a mainstay, but I think that cycling in and out is optimal. We have two (well, really 4) energy sources. I think it benefits us to optimize them both. If we eat more seasonally, with low carbs in mind, I think the question answers itself.

  18. Glad you talked about this Mark, I would be interested on what results would be for fully fat adapted people doing targeted carb cycling. That’s pretty much what I do, and I have to say, it’s mainly because of the pleasure some carby foods give me. Especially now in autumn, with all the kabocha and delicata squash, sweet potatoes etc. I just try to eat these on workout days, and to be honest my goals are simply optimal health rather than fat loss or workout performance! Maybe a post on how all this factors into longevity goals next time? 🙂

  19. Great information here and perfect timing for me. Couldn’t agree with you more Mark and getting the glycolitics (if that’s a word) down is key as I try to stay fit and practice Jiujitsu as much as possible and find that I need to increase clean carb intake just slightly to stay strong and capable. You just have to listen to your body. It will tell you almost everything you need to know.

  20. Hi I’m very very new to this way of eating, this blog is the first I’ve EVER read. Fruit and veg are carbs right? So if I cut them out (to cut the carbs out) where do I get all those nutrients from? We all know that poor quality supplements (and there are so many of them out there) are worthless to our health. Please help.

    1. Not all carbs are created equal. Usually when people refer to low-carb diets, they’re talking about removing processed, simple carbs, like sugars, pasta, bread, cake, etc. from your diet. Veggies are fine! In fact, vegetables should be a significant part of your diet. Fruits are debatable, though varieties with lower sugar are best. Go for berries or grapefruit and stay away from high sugar fruits like ripened bananas. Depending on your needs, you might also want to avoid high-carb tubers, like potatoes. Go for whole foods and avoid all the processed garbage.

  21. Theres a docu series on-line IThrive, about diabetes that really dishes out ketogenic diets.
    any comments?

  22. Good article and I particularly liked the little bullet point at the end about “getting adapted first”. I think the long view of nutrition in terms of “where will I be in eight weeks” is so much more effective than “what diet should I use today”.

  23. I was a big advocate of low carb / high protein diets for the last 6 years. Unfortunately, it is not for everyone nor everyone’s body. I went into ketosis and ended up with high levels of ammonia in my blood. I was in and out of the E.R and had no idea what was going on. We have to remember that hunter / gatherer tribes did not eat a steady diet. Quite the opposite. The theory of a lean sinewy meat eating man is quaint but fictional. High levels of any macro-nutrient be it Carbs, Fats, or Protein garner side effects. Telling an office worker, 175 lb man, to eat over 80 grams of animal protein per day is socially and ethically irresponsible at best. The long term gains are not worth the GERD, high acidic stomach, esophageal ulcers, and ammonia in blood. There are plenty of studies showing carb cycling, low carb benefits, I read them all, and practiced for 6 years. We should keep in mind, as Michal Pollen says, ” Every generation demonizes one macro-nutrient while glorifying another. ” Eliminating legumes due to a theory of Phytic acid being an anti-nutrient is charming but the complete antithesis of one of the most extensive studies on cultures and their longevity. Stuffing your digestive tract with beef and kale is not an ideal environment for your gut flora or your bodies ability to rest and repair itself even with probiotics. Imagine cooking a cup of beans and then taking a few and squeezing them in your hand, they would fall apart easily, try that with steak and then ask yourself what your body is required to do with that kind of digestive chore. I do not want to dismiss paleo for those under 40 who find it works, but being 40 means health repercussions that come with lost resiliency and no telomeres to be found. I am not pro refined carb, there is no flour or sugar in my diet but I switched from Paleo to limited animal protein at lunch time ONLY. For dinner I have a Dosa, a black bean burrito, a daal soup, or a variation of a legume based meal. My GERD went away in four days time, my esophagus ulcer healed without PPI’s. Above all, my energy went through the roof. It makes sense, good carbs produce serotonin and increase leptin which helped me feel incredibly satiated while LOSING WEIGHT. 7 pounds in the first week. I was FAT on a high protein diet, 215 pounds and I’m 5′ 10″, that is OBESE! I am now 180 by simply switching to a vegetarian legume based dinner. My digestive tract on Paleo had ulcers on one end and hemorrhoids on the other!!! I was bloated, woke up lethargic and with brain fog. So… do what ever feels good to you but if you feel any poor health side effects come on than keep in mind what I am saying. The best benefit for me has been to stop creating my own confirmation bias by continually looking up ‘studies’ that would confirm my predetermined belief system. On that note, keep in mind what Michal Pollen said, or think about the dozen studies from the early 80’s that demonized butter and were pro-margerine. There are good carbs that are not on the Paleo diet, legumes healed me and no ‘study’ claiming protein is a panacea will ever change my opinion. Paleo hurt my body, could hurt yours too.

    1. This comment is very helpfull. But coming from a plant based whole food diet I was shocked, on contrary, by the damages that cronically high level of sugars (whole food is sugar at the end) in the absence of animal proteins and fats could make after just a few months and the terrible effects within 1 year. That said by revolting the spectrum, an animal whole food based diet is not optimal if not mitigated by fasting (which is easier to do on such a regimen) and cyclical or seasonal pauses/plant based nutrition. Problem is for me:fibers. They make me bloated, not meat. I do agree that ancestral eating is not one and we should not demonize foods as beans. A perfect example they are. Some beans once in a week seem to be good, eaten everyday the messed my gut and caused anemia. Work in progress here..

  24. I think I don’t need that binge on carbs. Although It has been hard to lose fat (people say it is because I am above the 50 th), I don’t believe it. I’d rather research more about keto diet beccause I am sure I have not been following the protocol accordingly. If someone at 50 ths or more can help, I would love. Does female hormone block my weight loss? I am seeing a doctor next Monday.

  25. I am new to Keto but have heard from a couple people I follow that cycling some carbs is good for a womans hormones. I would also like to know if you have an article on Keto and low moods as I have heard that can be a side effect. I want to avoid having such a side effect. Thanks! Appreciate the well written articles here, just poking around for the first time.

  26. I commute to university 3 days a week, which is roughly ten miles (round trip) very hilly with some really steep climbs. I eat very low-carb, (never grains, refined sugar, white potato etc, I even eat very limited amounts of fruit & root vegetables) and I remain in ketosis most of the time. I eat in narrow eating windows, usually between 11am – 3pm because I am in University 9am – 7pm and thats the only window I get (I don’t feel there is time for breakfast and I hate to eat after 7pm because digestion inhibits my sleep)

    The problem is, I’m not fit enough to remain aerobic for all of these steep climbs, and I get very fatigued. I am constantly using glycogen, and rarely consuming more than 50g of carbs a day. Though my first step is to save for a turbo-trainer so that I can build my aerobic base (it is far too hilly to stay aerobic where I live, which is why a turbo-trainer will be good to let me stay aerobic for long amounts of time, allowing me to maintain a lower heart rate for my climbs on the road) I am questioning how I should make life easier for myself, really. How much carbohydrate should I eat? How should I cycle in the carbs? What kind of food would be good to eat?

    My boyfriend is always telling me to eat more (in general) but I am very concerned to gain weight. Last month, I was eating after 7pm, a fair amount of root vegetable, sweet potato, fruit and yoghurt and I actually gained a stone! I don’t know why I gain weight so easily, but it makes me very cautious with my diet. I used compressed eating windows and ate around 800 calories a day (perhaps causing metabolic damage?) while burning around 2400 (according to my heart rate monitor & polar loop pairing) and lost that stone in around 2 weeks (phew). I eat enough protein for my lean body mass, and no more than that, usually from fish or grass fed beef (as I found meat disagrees with my gut a bit, as does dairy and nuts) I eat a massive variety and quantity of vegetables, a bit of goats cheese & fair doses of olive oil. I am still looking to shave off a few pounds, but I think any belly fat retention is more due to cortisol than diet since I don’t eat much at all.

    I am finding great success with a ketogenic diet, especially the cognitive clarity I get with the ketones. I even supplemented with MCT oils during my exams which I found gave me superpowers! (I jumped about a grade) And paired with my (almost obsessive) weight concerns, I am cautious about how I should adapt my diet to my exercise needs.

  27. How about carb cycling if you get high blood glucose whilst doing keto? Mark mentions (in 21 day reset book) this happened to him and co-author – and it’s really important: e.g. For those doing keto for cancer management a high glucose level is totally counter-productive (Mark theorises it can happen when body gets to prefer ketones over ingested glucose and starts to ignore insulin’s efforts to provide it, leaving glucose to pile up in the blood). If so, what solution? A few weeks keto, then a week low carb but not to keto extent? (To maintain insulin sensitivity). Would appreciate input or a pointer to an info source on this.

  28. How about carb cycling / cyclical keto when you get insulin resistance due to being in ketosis?! Mark mentions in 21 Day Reset that he and co-author both got ‘pre-diabetic’ blood glucose results at times and theorises this could be due to being so ketone adapted that cells start ignoring insulin leading to accumulation of glucose in blood: a nightmare if doing keto to manage cancer and deprive cancer cells of glucose. I have recently come across the same high glucose readings (around 100) while keto. How to avoid this? 3 weeks on keto, a week or so off (but low carb) to ensure insulin resistance doesn’t engage? Anyone come across literature on this? Thanks!

  29. Such a great article! I love visiting a spinning class, but when the weather is nice there is nothing better than riding a bike on your way to work.

  30. Very interesting. My experience with resistance training is that the body produces all the glycogen it needs, if enough proteins are provided, expecially red meat. There is another component: sociality and food addiction’s memory. I find it easy to manage a carb-heavy “cheat” day once every two weeks. It makes so that you don’t miss the carbs and even remember how good steak and butter are vs those plastic pizzas and bowl of rice you coukd think to miss but your body did not. I keep fats very low on that day. The other days I am not low carb, more on the zero spectrum. Meat and fish the main staple. The “classic” keto doesn’t provide enough energy for daily training, it never worked for me even after 6 months of “adaptation”. Low carb neither, never fully switched to fat burning. Meat is a grat fuel, organ meat a supefuel. Recovery is very easy

  31. However, wouldn’t autophagy be audmented with 1/wk carb refeed and therefore longevity? If this is true would it also be true that limiting protein during the refeed increase autophageal results? Just wondering and I appreciate any and all help. Thanks in advance.

  32. This isn’t what “carb cycling” is like at all. Read The Adrenal Reset diet by Alan Christianson, the guy who invented the term. Healthy carbs everyday.