Post-Binge Biology: What Happens To Your Body When You Overeat (and 8 Things To Do Afterward)

‘Tis the season for consumption.

Cookies, cakes, and pies abound. Feasts happen on a regular basis. Candy is given and received as gifts. And there are parties immeasurable—at work, with family, with friends—where calorie-dense, rewarding food is handed out, like, well, candy. The holiday season is a practice in overeating, and it can be very hard to avoid. You may not want to even avoid it; there’s something to be said for letting loose now and again on special occasions, especially when holiday cheer is in the air.

But what happens to your body when you overeat? And what can you do about it?

The type of overeating most people do across the holidays is high-sugar, high-fat, and relatively low protein. These are your cakes and cookies. Your brownies and fudge. Your pie for breakfast. This is the worst kind of overfeeding you can do. Research shows that just six days of high-sugar, high-fat, low-protein overfeeding rapidly increases fat deposition in the liver and muscle. Seven days of overfeeding reduces whole body insulin sensitivity, inhibits glucose clearance, and impairs endothelial function.

If you keep doing it, say, over the course of a month, bad things pile up. You get incredibly insulin resistant. Your liver fat increases. Your body weight and overall body fat increase. Your C-reactive protein increases, an indication of inflammation. A class of antioxidants called plasmalogens also increase, which means your body is fighting oxidative stress.

One problem with the studies is that you have to distinguish between quality and quantity; overfeeding with different foods elicits different effects. For instance, in the study that looked at overfeeding’s effect on lipid metabolism, the subjects overate by eating more cookies, potato chips, and cheesecake and drinking an oil-based liquid supplement. Overeating a bunch of that junk food is different than overeating steak.

In fact, research shows that overfeeding protein has little to no impact on fat or weight gain compared to carbohydrate or fat overfeeding.

Another factor to consider is individual variability. Some people are “obesity prone.” Others are “obesity resistant.” In one study, obesity prone and obesity resistant subjects had different responses to three days of overfeeding. The obesity prone people saw their fat oxidation rates drop during sleep; they burned less fat. The obesity resistant subjects saw their fat oxidation rates unchanged during sleep; they continued burning fat like normal.

So, when we talk about the effects of overeating, we have to keep in mind that the effects will  differ between individuals and vary if you’re eating a pound of roast lamb versus eating half a pie. But the general point still stands: Overeating can make you gain weight, gain liver weight, induce oxidative stress, cause insulin resistance, increase inflammation, and make you sicker, fatter, and more unwell the longer it goes on.

But am I too late in saying this? Are you already dealing with the effects of excess? Here are 8 tips for scaling back and minimizing damage. 

1. Favor Protein

As explained above, overfeeding protein has more neutral metabolic and body composition effects than overfeeding fat and carbs. Some effects are even positive, like boosts to energy expenditure during the day and during sleep. Load up on the turkey, the lamb, the beef rib roast and keep portions of mashed potatoes, pumpkin pie, stuffing, candied chestnuts, and cookies more reasonable. One advantage of overeating protein is that eating less of the other stuff tends to happen inadvertently.

2. Eat Vinegar

Vinegar, whether it’s organic apple cider vinegar with the mother still swimming in it or standard white vinegar from a two gallon jug, improves glucose tolerance and keeps postprandial hyperglycemia and insulin tamped down. The trick is eating the vinegar (maybe a side salad before the big meal dressed with a vinegar-y dressing) 20-30 minutes before you overindulge.

This is most relevant for meals containing carbohydrate.

3. Exercise

No, exercising after overeating is not “binge behavior” or evidence of an “eating disorder” for most people. It’s simply physiological common sense. You consume a ton of calories, calories in excess of what your mitochondria can process and convert to energy. What makes more physiological sense—just sitting there, letting that extra energy circulate and eventually accumulate on your body, or creating an energy deficit so that the extra energy is utilized?

This isn’t about “calories,” per se. It’s about throwing a ton of energy toward your mitochondria and giving them a job to do—or letting them languish in disuse. It’s not about “weight gain,” necessarily. It’s about energy excess and the oxidative stress and inflammation that results. It’s about not being wasteful. If you introduce a ton of energy and then do nothing, you are wasting that potential.

Besides, research shows that exercise counteracts the short term negative effects of overfeeding, including countering the negative epigenetic effects seen in the adipose tissue of over-consumers. The best time to exercise is immediately after eating. Of course, I wouldn’t suggest doing an intense CrossFit workout with a belly full of food, but something light like the several sets of 10 pushups, squats, lunges, and situps in this study done immediately after does the trick.

4. Accept It As a Positive Experience and Move On

That overeating induces oxidative stress enough to trigger the release of antioxidant compounds may mean the occasional acute bout of overeating can act as a hormetic stressor that makes you stronger in the long run—provided it stays acute and hormetic. It could actually be good to overeat once in awhile. Yeah, go with that.

5. Have Some Black Tea

I just did a big definitive guide to tea, and it turns out another benefit of the stuff is that it actually speeds up digestion after eating. It beats alcohol, espresso, and everything else that people tell you helps digestion.

6. Go For a Walk

Right after you overeat, a 20-30 minute walk will reduce blood glucose and speed up gastric emptying—helping you process the meal much faster and reducing the feeling of fullness. Longer walks are even better and can also reduce the postprandial insulin spike. It has to be immediately after though; waiting even 30 minutes will suppress the effects.

7. Get Out Into the Cold

It’s the perfect season for cold exposure (in most places). Even mild cold exposure—just 18°C or 64.4°C for 2.5 hours—is enough to increase energy expenditure without increasing hunger or subsequent food intake. That’s downright comfortable for a lot of people. If you went out into sub 50°F weather, I bet you could get the same effects even faster.

8. Don’t Throw In the Towel and Continue Overeating For the Foreseeable Future or “Until the New Year”

A consistent finding in the literature is that people gain weight during the holidays and never quite lose it. They don’t do this because they had an extra slice of pumpkin pie at Thanksgiving or five cookies on Christmas morning. They gain and retain the weight because they consistently overindulge for the entire duration of the holidays. They figure “Oh, I ate badly yesterday, which means this week is shot. I’ll just do better next Monday,” and then keep that mindset going for months.

Well, one way to break that cycle is to stop that “this week/month is shot” mindset. No, just because you ate badly yesterday doesn’t mean you should eat badly today and tomorrow. That will compound your problems and dig an even deeper hole. Stop overeating immediately.

Overeating happens. It’s okay, or even beneficial if used judiciously. There’s nothing like filling your belly with your grandma’s signature dish, or really letting loose with your favorite people in the world. Humans are feasters by nature. We like to make merry and eat big to ring in the good times. Just make sure you contrast it with leaner days. (Intermittent fasting around the holidays is great for this.) A feast no longer qualifies as a feast if you do it consistently. A party’s not a party if you party every day. Contrast is the stuff of life—heed that rule and all will be well.

How do you approach holiday overeating? What do you do to counter the effects? What physical behaviors and mental models do you adhere to? Let me know in the comment board.

Take care, everyone, and happy feasting!


Surowska A, Jegatheesan P, Campos V, et al. Effects of Dietary Protein and Fat Content on Intrahepatocellular and Intramyocellular Lipids during a 6-Day Hypercaloric, High Sucrose Diet: A Randomized Controlled Trial in Normal Weight Healthy Subjects. Nutrients. 2019;11(1)

Parry SA, Turner MC, Woods RM, et al. High-Fat Overfeeding Impairs Peripheral Glucose Metabolism and Muscle Microvascular eNOS Ser1177 Phosphorylation. J Clin Endocrinol Metab. 2020;105(1)

Leaf A, Antonio J. The Effects of Overfeeding on Body Composition: The Role of Macronutrient Composition – A Narrative Review. Int J Exerc Sci. 2017;10(8):1275-1296.

Schmidt SL, Kealey EH, Horton TJ, Vonkaenel S, Bessesen DH. The effects of short-term overfeeding on energy expenditure and nutrient oxidation in obesity-prone and obesity-resistant individuals. Int J Obes (Lond). 2013;37(9):1192-7.

Bray GA, Redman LM, De jonge L, et al. Effect of protein overfeeding on energy expenditure measured in a metabolic chamber. Am J Clin Nutr. 2015;101(3):496-505.

Ostman E, Granfeldt Y, Persson L, Björck I. Vinegar supplementation lowers glucose and insulin responses and increases satiety after a bread meal in healthy subjects. Eur J Clin Nutr. 2005;59(9):983-8.

Solomon TPJ, Tarry E, Hudson CO, Fitt AI, Laye MJ. Immediate post-breakfast physical activity improves interstitial postprandial glycemia: a comparison of different activity-meal timings. Pflugers Arch. 2019;

Heinrich H, Goetze O, Menne D, et al. Effect on gastric function and symptoms of drinking wine, black tea, or schnapps with a Swiss cheese fondue: randomised controlled crossover trial. BMJ. 2010;341:c6731.

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.

If you'd like to add an avatar to all of your comments click here!

20 thoughts on “Post-Binge Biology: What Happens To Your Body When You Overeat (and 8 Things To Do Afterward)”

Leave a Reply

Your email address will not be published. Required fields are marked *

  1. This is a really great blog. Thank you for mentioning that pre or post celebration exercise is not orthorexic or otherwise unhealthy. My philosophy has been: “Hell, if I have all this extra energy in my system, I might as well put it to good use and really rock my workout!”

    Also, what do you think of intermittent fasting or time restricted feeding as another tool to balance celebratory eating?

  2. Outstanding. I love the practicality of this post and Mark’s counsel generally. Since I got switched on to Mark’s stuff I’ve seen a dramatic increase in my energy levels and while the weight loss is less evident, I sense the fat loss is happening – its just being masked by my adding muscle mass. I know this because I’m not much lighter but all my clothes fit TONS better.anyhow – I have some important weight loss and fitness goals to achieve over the holidays, but I know the bad food days are going to be a challenge. This gives me some real strategies. Thanks.

  3. Mark I really enjoyed this blog post. It is one your best and backed by science. I am lucky myself that I have learned over the years not to binge during the holidays. I have been pretty successful the past five years and once they are over I do not feel I missed anything. Thanks for the excellent piece.

  4. Thank you Mark all you do. I physically have pain from overeating at family celebrations. We have constant food all day and cheerleaders encourage everyone to eat. I’m stuffed before the main course and have to force one or two of the plethora of desserts as to not insult the particular baker We always have somewhat healthy choices of guacamole, shrimp, deviled eggs, chicken strips as apps but we also have a ton of the salty carbs you can’t stop eating. In addition we our encouraged to drink. No empty hands allowed! So as a glutton when presented a smorgasbord it’s tough. As a travel salesman with expense account it’s tough. As a kid who grew up being known as the human garbage disposal its tough.

    I obviously have an emotional attachment to food but so does most of my midwestern family. I’ve done primal, paleo, whole 30, IF, and a few body transformation challenges but every time I fall back into old patterns and every time it is harder to lose the gains after the fall. I live life thru my senses and food is almost orgasmic for me. Any advice on how to become disciplined, unaddicted, and DESIRE health over sensory explosions in my mouth would be helpful. In theory desire is always stronger than satisfaction. I desire to be healthy, fit, energized but the desire for that life long goal is disrupted by the satisfaction a binge brings.

    I’ve quit drugs, pot, smoking. I could quit alcohol easily as I’ve done for many months in the past but I can’t seem to quit falling back into unhealthy eating habits.

    Not an easy case but considering the 1000’s of souls you’ve helped I’d appreciate any advice. I’m spending 6 days over Christmas with 16 family members in one house on a ski mountain and food has been discussed more than events! PS merry Christmas!

    1. I totally understand what you live. Same here. My solution is stopping fighting against who I am and how I deal with food.
      On my good days I eat Primal. But I know the urge to eat bread or pasta might come back any day and I try to be peaceful with that. To balance the overeating I do IF, that leaves my body enough time to process that food.
      It works pretty well for me and prevent too much weight gain.
      I hope it can help.

  5. Thanks Mark
    Good thoughts.
    I picked up my grandkids after school today and enjoyed an hour of Nordic skiing at 3F. The snow is perfect right now. I’ll keep my daily AC vinegar going and add a bit more black tea…while enjoying the protein of the season. And continue to Get Outside Up North in Minnesota.

  6. My approach: I put the scale away and try to ignore pants that are too snug. I’l fix in in January. My relationship with food stresses me out ALL THE TIME, so rather than getting depressed about all of the deliciousness that I am nibbling on (it adds up!!) and drinking, I decided not to pay attention for now. I’m still stressed and depressed about my pants being too tight, but at least I don’t have specific numbers to fret over (and those jeans are size 2 so I am not exactly running serious health risks, with a diet heavy in fresh produce and low in processed food most of the time).

    1. You and I sound like the same person. I put the scale away – had to as the most minor fluctuations were causing me stress. Also a size 2 but they are not as loose as I’d like them to be. I’ve pulled my tape measure instead. I’m far too obsessive to fall deep into this around the holidays but I am not waiting until January. I try to capture a day here and there. Obviously when January rolls around I’ll be all in. My face has a tendency to show any weight gain (and my hips) so the change in my face is primary motivation now.

      You can never talk about this because no one wants to hear a size 2 lament about weight gain. Good luck to you Anne!

  7. You’re probably right about everything but I don’t like cold, I like to sweat. I live in coastal SC so we rarely get into the teens but anything below 60° is cold to me. I overeat on purpose occasionally just to maintain my weight but it can cause digestive issues.

  8. Moderation of sweet calorie bombs is extremely difficult for me, no matter how “clean” the ingredients. I’ve tried and tried over the years, and I’ve finally come to the conclusion that I actually achieve greater quality of life by simply abstaining altogether.

    I prefer the drug-free buzzes and highs of human existence — the even-keeled joys of movement, creativity, nature immersion, human connection and delicious whole-food satiety. Sweets derail all of this for me. In my mind, there is nothing “restrictive” about abstaining from sugar, flour, alcohol, and all the like. I don’t fear “missing out” on grandma’s cookies any more than I fear “missing out” on meth.

    1. Refined sugar is like heroin for me… One cookie and it is all over. Makes my head hum in a bad way. I abstain… Feel much better!

  9. Excellent. I have been a low-carber for 18 years, and incorporated intermittent fasting 3 years ago. I generally eat about four or five higher carb meals a year – an anniversary meal, a birthday meal, and a couple around Jewish festivals. With eight days of Chanukah coming up next week, I am planning several longer fasts this week. Sunday night is my planned carb meal – but what that means is I will have a keto meal – salmon, salad, zucchini latkes, cauliflower and cheddar latkes – and will then indulge in my one doughnut per year. Last year I had more of a carby meal and I felt truly awful afterwards. The balanced healthy meal prior to an indulgent dessert tends to leave me feeling ok afterwards. That will be my only meal of the day. The following night is a family get together meal – I aim to fast again until supper, and I’ll enjoy that meal, but I will skip the dessert and not go off keto (helps that I converted three of my relatives to keto). After that, I’ll probably do another overnight fast to get back into my swing.

    I doubt I’ll have the opportunity to exercise or get out into the cold after those meals – being with family and having young kids precludes that – but I’ll definitely make sure that the salad I eat before the doughnut dessert has a vinaigrette dressing!

    Happy holidays everyone.

  10. I totally lol’d at 18C being *cold*. That can be a summer day here – shorts and tee shirt kind of weather. It’s *warm* here today at -11C (-20 C with the wind chill). I’m often out walking in far colder temps than that!

  11. Thanks, Mark, very helpful. What about enzymes? I had very high Triglycerides for a long time (about 3 years) before I figured out how to handle it so it’s lower. It affected my pancreas without totally destroying it. So I think for me, the most effective fix for “oops, too much partying” is a comprehensive enzyme supplement. I don’t take it daily because I want my pancreas to work by itself. But it can sure help recovery for me. Bile salts also. But that was mainly when I went back to keto after my gallbladder was removed. Temporarily I needed to use that to recharge the bile in my system.

    I’ve taken chlorella and used that as my only food for about 20 hours when I’ve overeaten before also. A few years ago I had heard of actresses going for days on just that and found that it works for me.

    At the moment I’m fascinated by Carnivore eating so this holiday I’m making one sweet (recipe from your site, the Peppermint Bark) and probably will only have meat and cranberry sauce.

    I think being carnivore before the holidays has really helped me to put thoughts of carbs out of my mind. My thoughts went from “I will not live the rest of my life without cookies” to “Cookies are tasty, but not required for happiness.” And I credit that to the meat. Only being strictly keto has every had such a strong effect and it was still a temptation. Now it’s more like a “nice to have” not a “no-no.” It’s a subtle difference.

    I’m not going to swear that I’ll never eat any other way again, but this is helping me now, so I’m going to go with it for a while.

  12. 8. Don’t Throw In the Towel and Continue Overeating For the Foreseeable Future or “Until the New Year”

    Awww, come on! That was my game plan. 🙂

    1. So glad I read this on Boxing Day, And at least I’ve eaten all the maltesers already!

  13. Fantastic post. Did not know about the effects of vinegar/tea. Well written, non-judgemental, solid advice. Personally, my holiday did not include any refined sugar/flour/breads, but that’s mostly because I feel so crummy afterwards, it just isn’t worth it. Thanks for continuing to post with a positive spin in a world where, currently, negativity rules… 🙂