Reverse Dieting and Metabolic Damage: The Basics of Metabolic Adaptation
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Reverse dieting, in its simplest form, is the slow and controlled addition of calories after a period of caloric restriction. This addition of calories back into the diet is to minimize rebound weight gain as much as possible and in theory, improve metabolic rate slowly over time. Reverse dieting has been popularized by the fear of metabolic damage, or the slowing of one’s metabolism due to chronic dieting. While metabolic damage is a debatable term and condition, there’s no denying metabolic rate slows as you lose weight.
I received a question recently about reverse dieting and metabolic damage and thought it was worth sharing. You’ll find the key takeaways and things to know about metabolic damage and reverse diets first, followed by the full conversation.
Here’s what you need to know about metabolic damage:
- As you lose body fat and body weight, you burn fewer calories. This happens through a number of processes (some mentioned below), but the biggest contributor is simple – it requires less energy to move 175lbs than 200lbs.
- The metabolism slows even further the leaner you become. I like the death by fat loss example. If you weigh 200lbs today and go on a diet to lose 1lb/week, you’d be 150lbs at the end of a year, 100lbs at the end of two years, and you’d be dead by the time you weighed 50lbs at three years. It’s not linear because your body will make changes to become more efficient and burn fewer calories, reducing your metabolic rate and the amount of calories you need to maintain a certain weight.
- Even if you don’t lose weight all that successfully, being in a constant state of semi-restriction may lead to a “slowing” of your metabolic rate. The body adapts and will eventually make even a slight calorie deficit its new norm.
- Burning less from eating less can be applied to exercise as well. Aside from body weight differences, you’ll likely burn fewer calories during workouts when you’re in an extended caloric deficit. Meaning, a lighter body burns fewer calories during exercise, and an unfed body burns even fewer calories during exercise. We’re hardwired to be as efficient as possible to avoid starvation.
- If you maintain your weight on a lower calorie total, you may benefit from a “reverse” diet or gradual ramp up period. This would require tracking nutrition and consistency, but it can be done. How much improvement you’ll see is hard to tell. Since you’ll be increasing calories to 50-100 calories above maintenance one week (or month) at a time, it will take some time and dedication.
- If you’re in a good place, keep “diets” or fat loss phases short with plenty of breaks to be safe. An example would be a 500 calories/day deficit for an 8-week period, combined with a 4-week period of maintaining your new weight. This would ensure that you lose fat at a healthy rate and allow your body time to adjust to its new weight before dieting further or staying put.
Continue reading below for the full conversation:
Q: Do you have thoughts on reverse dieting? And all the people who talk about damaging their metabolism from undereating for a long time?
Metabolic damage probably isn’t the best term, but adaptation to metabolic rate is inevitable with dieting. As body weight decreases, your body burns fewer calories during exercise and in everyday life because you’re smaller. You also unconsciously move/fidget (non-exercise activity thermogenesis – NEAT) less and burn fewer calories from that. There are also some metabolic changes to digestion/absorption rates and potentially hormonal changes. All in all, the “metabolism” slows as you diet.
If you ended a diet at 1,200 calories/day and immediately go back to 2,500/day, you’ll store more fat. It’s a good idea to reverse diet or ramp back up slowly to allow those processes to readjust to higher intakes. There’s a chance body weight/body stores remain unchanged for quite some time on the reverse diet.
Q: So, for example, if I ate an average 600-800 calories per day for 2 years (I legit thought I was being healthy bc I lost 25lbs REAL quick), and never really moved my calories up more than an average of 1000per day for the next 3 years, that could be why I currently maintain 138lbs around 1400 calories per day? Lol sorry that’s a long and personal question I feel like I HAVE to drop down to like 1200/day to see any real fat loss, and even then, I plateau around 133. And I’m 5’3. My current priority is definitely gaining strength/body recomp, so I’m not stressing fat loss much, but I’m just trying to decide if I should plan on slowly ramping up my calories through the winter and praying that’ll make it easier to cut next year.
No worries. I’m always happy to answer a question or two. Your current maintenance may not be “high” by any means, but it’s not terrible. Something to keep in mind is your style of training. Powerlifting is typically strength/hypertrophy-friendly but doesn’t burn a ton of calories/energy during training itself. So, if you’re doing primarily low-rep sets and have a relatively sedentary lifestyle outside of that, your energy expenditure may not be that high. Anyway, for your goals I think aiming
To increase calorie intake over the next 6-12 months could help. Even though research hasn’t necessarily proven reverse dieting to “increase” metabolic rate, it should work in theory. What is guaranteed to increase metabolic rate is the addition of muscle. If you maintain at 1,400 and raise to 1,500, you’ll gain minimal weight but may experience the recomp effects.
Over the course of time, 138 with 100lbs of lean tissue becomes 138 with 105lbs of lean tissue. Your maintenance may become 1,500+ calories/day at that point. Or they may be even higher. It’s hard to say since everyone is so different.
The takeaway would be that reverse dieting or increasing metabolic rate/maintenance calories is a SLOW process. And most of the adaptation will come from increasing muscle/active tissues vs fat. There are hormonal/physiological factors wrapped up in eating more, but I wouldn’t spend much time worrying about them. Eat more over time, as slowly as possible, and your maintenance calories should (will?) increase if you’re training hard.
Q: I’m not expecting drastic changes in maintenance calories by any means, but yeah, I’m definitely prioritizing increasing lean tissue over dropping fat right now. Ya girl is tryna be strong. Also I decided I should suck it up and start adding cardio again.
I like it. There’s a difference between maintaining at 1,400 cals/day and eating 1,600 cals/day with 200 extra calories burned. I’d advise low-intensity stuff like walking or short, intense conditioning circuits. Jogging or stuff in that middle realm will burn cals but seems to be terrible for muscle/strength gain.
A stairmaster, incline walking on a treadmill and bike sprint intervals would work well.You could also add extra accessory work and run through them like supersets, dropsets, or go unilateral and work straight through without rest, going from one side to the other.
I hope this has been informative. If you have questions about your nutrition, metabolic rate, or anything else, feel free to shoot me an email. And if you haven’t downloaded my free book, Nutrition Made Easy 3.0, you can do that by entering your info below or clicking here to learn more.
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