Reverse dieting claims that by slowly ramping up your calories — often by as little as 50 calories per week — you’ll reputedly “repair” your metabolism (which was damaged during the diet), prevent weight regain, and build your metabolic capacity to a point where you can eat significantly more calories without gaining any fat.
But there are some serious problems with the idea.
To kick things off, let’s examine the various components that contribute to the total number of calories we burn each day (also referred to as total daily energy expenditure or metabolism), as understanding this will lay the groundwork for the rest of the article.
- Resting Metabolic Rate (RMR) – This is the minimal amount of energy your body needs to do all of the weird and wonderful things that keep you alive, like pumping blood around your body, keeping your brain firing, digesting last night’s questionable takeout, and making sure you keep breathing even when you forget to think about it.
- Thermic effect of food – This is the energy expended digesting, absorbing, and storing food.
- Physical‑activity energy expenditure (PAEE) – This is intentional exercise, like lifting, cardio, sports, etc. and non‑exercise activity thermogenesis (NEAT)–the unstructured physical activities we partake in each day, such as standing, walking, fidgeting and chasing your toddler around the house so they don’t accidentally off themselves.
All of these components are dynamic and are impacted by your energy status. If you eat in a caloric deficit and lose weight, your resting metabolic rate drops to account for the losses in body fat and lean mass. You’re eating less food, so the energy required for digestion is also reduced. You’ll also burn fewer calories moving around and exercising; this is partly from reduced energy levels, but also because your body becomes more ‘efficient’, using fewer calories for the same task. 1 2
Underneath all of this are hormonal shifts pulling the strings. Hormones such as leptin (released from fat cells) and insulin decrease, signalling to your brain that “energy stores are low,” this makes you hungrier and reduces the number of calories you burn. Thyroid hormones—especially T3—also take a hit, lowering the number of calories your body uses at rest. 3
Reverse dieting was introduced to bridge the gap between the end of a diet and maintenance, so people could reverse these adaptations without regaining body fat. Unfortunately, the fitness industry did what it always does: bastardised it into a miracle cure with claims so wild you would think Kanye West was behind all of this.
In this article, we’ll break down why those claims don’t hold up, why so many people think reverse dieting “worked” for them, and how to approach it in a way that allows you to get back to maintenance without an unnecessarily long reverse dieting period.
Where should we start? Hmm, oh! Let’s start with my favourite–reverse dieting can fix your broken metabolism.
1- Does reverse dieting repair your metabolism?
No, because nothing is damaged.
As I mentioned above, some adaptations happen during weight loss. This isn’t ‘damage’, but mechanisms your body has in place to prevent you from losing more weight. Fortunately, these adaptations are mostly reversed as you end the diet and return to maintenance. 4
For example, Nunes and colleagues conducted a systematic review of 33 studies looking at whether metabolic adaptation occurs after weight loss in adults. 27 out of 33 studies reported some level of metabolic adaptation, but most studies reported these adaptations were either non-significant or completely dissipated at caloric maintenance. 5
I say mostly because not all of these adaptations are due to the deficit–some are due to losing body fat and fat-free mass. 6 Therefore, as long as you’re maintaining a leaner body, your metabolism will be lower than when you weighed more because you don’t require as much energy to maintain your new, lighter body weight.
Importantly, these changes are expected and proportional to the amount of weight lost. There’s nothing permanently broken about your metabolism, and while metabolic adaptation is real, it’s fairly modest. In the Nunes study mentioned earlier, metabolic adaptation ranged from 30 to 100 calories.
2- Does reverse dieting boost your metabolism?
Arguably, the most seductive claim of reverse dieting is that you can eat hundreds – if not thousands – of calories by slowly reversing out of the deficit without gaining any body fat.
Unfortunately, your metabolic rate won’t increase beyond what’s expected for your body composition at any given body weight.
Just to be clear, there is an increase in energy expenditure when you eat more, but that increase comes from three factors:
- The body uses more energy to digest and store the extra food consumed
- More calories mean more energy, which leads to more movement
- It takes more energy to move a heavier body
It’s that last point that throws a wrench in this particular reverse dieting claim. Your metabolic rate scales with body size and composition since it costs more energy to maintain and move a heavier body.
For instance, in a 6-week overfeeding study, participants consumed 50% more than their maintenance intake — roughly a 1,500-calorie surplus. Their resting metabolism increased by 12% and they burned more energy walking and cycling (11% and 9% respectively) simply due to being heavier. 7
And a classic study by Leibel and colleagues illustrates how your metabolism follows gains and losses in body weight (specifically, muscle and fat). The researchers tracked metabolic changes as participants gained 10% of their body weight, returned to baseline, and then lost 10% and 20% of their body weight. 8
As shown in the image below, daily energy expenditure increased as participants gained weight, decreased as their weight returned to baseline, and then decreased further as they lost weight.
Finally, Johansen and colleagues conducted an 8-week study in which they overfed participants by approximately 1,000 calories per day above their maintenance needs. The researchers wanted to see whether overfeeding triggers a kind of ‘reverse’ metabolic adaptation—i.e., does the body ramp up energy expenditure more than expected from the increases in body weight?” 9
On average, participants gained 7.5 kg over 8 weeks (half of which was body fat). Their total daily energy expenditure increased by 7–10%, almost entirely due to the weight gain. After adjusting for gains in fat and fat-free mass, sleeping metabolic rate rose by only 43 kcal/day and 24‑h energy expenditure by 23 kcal/day more than expected, indicating no meaningful “reverse metabolic adaptation.”
When we take all of this together, the only reliable way to ‘boost’ your metabolism is to gain weight, since your metabolic rate increases in proportion to the fat and muscle you gain. 10
Other than that, it’s physiologically impossible to eat thousands more calories than your maintenance needs at a given body composition while staying just as lean as you were at the end of the diet. Yes, your energy expenditure will experience a small bump as you shift from eating in a deficit to maintenance, but this is a normal consequence of getting out of the deficit.
To illustrate, let’s say someone starts a diet weighing 170 lbs, and their maintenance intake at this weight is 2500 calories per day. After dieting, they drop down to 160 lbs, and their maintenance intake is now 2000 calories per day. As they increase calories and exit the deficit, their metabolism might stabilise around 2300 calories per day. As long as they maintain this lighter body weight, their maintenance calories will remain around 2300 (assuming no drastic changes in activity). You can see this visualised below.
3- Can reverse dieting prevent weight regain?
It can. But not because of reverse diet magic. The actual reasons are much less fantastical.
The first reason is that you’ve extended the deficit.
Let’s say you’re eating 1800 calories at the end of the diet, and your new maintenance is 2300 calories (i.e. your maintenance needs at your new, leaner body weight). If you add 50 calories each week, it will take you another 11 weeks to return to maintenance. I don’t know about you, but if I’ve just spent several months eating fewer calories, the last thing I want to do is spend another three months in a deficit.
Second, reverse dieting can help individuals avoid overshooting their new maintenance level.
People tend to gain weight at the end of a diet because they revert to their old, pre-diet habits, resulting in a slow drift into a caloric surplus.
Reverse dieting provides a structured approach to returning to maintenance calories. Sure, it’s unnecessarily long-winded, but it keeps people tracking their nutrition and weight, making them more likely to catch and correct any unwanted weight gain before it becomes a problem.
Additionally, a slow, methodical increase in calories can lessen the psychological mindfuck that accompanies a faster increase in calories. If someone thinks they’re eating more while maintaining a lean physique, they’re more likely to continue with the good habits, which becomes a positive feedback loop.
Third, people confuse weight gain with fat gain.
As you introduce more food back into your diet, your weight will increase for two reasons: You have more food in your stomach, and there’s an increase in muscle glycogen and water.
So, let’s imagine someone ends their diet and begins eating more – how would this look in terms of weight change on the scale?
One gram of carbohydrate comes with about 3 grams of water. If someone bumps up their intake by adding 100g of carbs, that’s ~400 g total weight gain (100 g carb + 300 g water), or just under 1 lb on the scale. 11
The stomach typically holds about 1-1.5 litres after a meal and can stretch to 4 litres in extreme cases. Of course, you aren’t going to be eating until you pop, so for the sake of this example, let’s say at maintenance there’s about 1.5 litres of food and liquid hanging around in your stomach until it digests, which would translate to roughly 3 lbs on the scale. Add the water weight from glycogen and the physical weight of more food mass, and you might see a 4 lb increase in the first few days.
Reverse dieting in the typical fashion (adding a minuscule amount of calories back into the diet each week) avoids the abrupt spike in scale weight, which can seem like you’re eating more food without gaining fat. But in reality, you’ve increased calories by such a small amount that it’s going to take weeks for it to be reflected on the scale.
But what about all the reverse dieting success stories?
I’m sure you’ve seen the social media posts. Two photos positioned side by side–in one, someone looking sad, bloated, and completely out of shape. The second is a more recent photo of them beaming as they show off their ripped, lean physique. The accompanying text laments how they couldn’t lose weight on super low calories. It was only by reverse dieting for several months that they were finally able to lose fat while eating twice the amount of calories.
Hold on, Harry, before you go signing up for the school of witchcraft and fuckery, let’s look at what’s really going on here because what seems like reverse diet magic has a far less mystical explanation.
Better tracking and adherence
Ok, fuck it–I’m going straight for the jugular: The reason these people weren’t losing on the lower calorie intake is because people suck at accurately reporting how much they eat. 12
Unsurprisingly, it’s much easier to stick to the diet if it involves more food. They’re no longer trying to white-knuckle their way through 1000 calories each day and then grossly overeating on the weekend, unknowingly adding thousands of extra calories to their weekly average. They start measuring things more honestly because there’s less guilt to hide their actual intake. The secret snacks, licks, and bites that were adding hundreds of calories to their daily intake are now tracked because they have the room in their caloric allowance to fit them in.
So, part of this ‘magic’ is simply the result of going from a poorly tracked lower-calorie target, which was likely closer to their maintenance, to an accurately tracked higher-calorie target, which finally put them in a consistent calorie deficit.
There’s considerable variability in people’s responses to overfeeding.
Two people could eat an identical surplus, but one individual would gain less weight.
The table below illustrates this variability across a handful of studies where individuals were overfed by 500-2000 calories per day. Within each study group, some individuals gained significantly more weight than others, despite a similar surplus; the highest gainers put on 1.8 to 5.1 times more weight than the lowest gainers. 13
One major reason for this difference is NEAT (non-exercise activity thermogenesis) — the calories burned through small, unconscious movements like fidgeting, standing, or pacing. Some people automatically ramp up these little movements when they overeat, effectively burning off the extra calories, while others don’t.
A notable example of this phenomenon comes from a 1999 study by Levine and colleagues. The researchers fed participants 1000 calories above their maintenance needs. On average, increases in NEAT accounted for about two-thirds of the rise in daily energy expenditure. But the range was huge; some people saw a reduction in NEAT, and one individual increased their NEAT by almost 700 calories. As you would expect, the participants who increased NEAT gained less fat than participants who didn’t experience the same increase. 14
Earlier in the article, I referenced a study by Johansen and colleagues.9 In that same study, the researchers followed up with participants six months after the initial overfeeding period, and found something interesting: people with a more “spendthrift” profile — whose metabolisms ramped up more during overfeeding — lost more of the fat they had gained once they went back to normal eating, while those with a more “thrifty” profile – whose metabolism didn’t ramp up as much during overfeeding – held onto more of the fat.
So, what the hell does this have to do with reverse dieting?
The people who experience the most dramatic results from a reverse diet are the individuals who respond better to overfeeding and, consequently, the ones more likely to shout about the ‘magic’ of reverse dieting on social media. Meanwhile, individuals who don’t experience as big a difference aren’t posting about their reverse diet success, so all you see is an endless stream of the winners, which only reinforces the idea that reverse dieting is a miracle.
The reduced-deficit effect
Imagine someone ends a hard diet on low calories, then slowly increases their intake. Let’s say that, over a few weeks, they’ve reduced their deficit from 800 calories to just 200 calories. Reducing the size of the deficit will lead to increased NEAT, training performance will improve, water retention will decrease, and muscle glycogen will begin to refill. All of these things will help them appear leaner.
Although they’re eating more food relative to what they were eating at the end of the diet, they’re still in a small deficit, and over time, they’ll continue losing fat, albeit at a slower rate. As an outsider looking in, you’re only seeing two variables – the increase in food intake and their physical appearance – which can make it seem like they’re eating more while getting leaner, when in reality they’re getting leaner because they’re still in a deficit.
There’s another related factor here – energy compensation. In a previous article, I referenced a study by Willis and colleagues who found that total daily energy expenditure rose with physical activity only in people who were weight‑stable or gaining weight; in those who were in a calorie deficit, energy expenditure was essentially flat despite increased activity.
As it relates to reverse dieting, it’s common to see people pair an aggressive deficit with equally aggressive training. In this scenario, the body clamps down on energy expenditure, and the extra activity doesn’t increase their daily burn as much as you’d expect. Once they start eating more, the constraint is lifted, and the physical activity translates to an increase in their energy expenditure.
“Who cares? Let people do what they want”
I agree. People can do what they want, and if you prefer a super gradual reverse diet approach—knock yourself out. However, you should make that decision knowing that you’re choosing a longer, more restrictive path when a faster, more straightforward approach would yield the same results.
More importantly, unnecessarily prolonging your time in a deficit also prolongs the duration of metabolic adaptation, which means more time spent battling hunger, low energy, reduced libido, and poor training performance.
And for everyone who would rather not do that, here’s a much better way to end the diet.
How to reverse diet properly
You want to get out of the deficit as soon as possible without ending up in a surplus. This means being able to determine your ‘new’ maintenance–that is, your maintenance intake at your new, lower body weight. Thankfully, this is pretty easy to do if you’ve been tracking your scale weight and calorie intake.
Note: I’ve created a calculator that will do the math for you. It’s also more accurate than the method below. You can download it for free here. Yes, I will ask for your email address because nothing is free, fuckface.
Step 1: Work out your average weekly weight loss. Calculate how much weight you’ve been losing on average each week.
Step 2: Convert that into calories.
- If you’re tracking in pounds: multiply your weekly loss by 500.
- If you’re tracking in kilograms: multiply your weekly loss by 1100.
This is the size of your daily calorie deficit.
Step 3: Find your average intake. Work out how many calories you’ve been eating per day, on average, over the same 4-week period.
Step 4: Estimate your new maintenance. Add your daily deficit (from Step 2) to your average intake (from Step 3). That’s roughly your new maintenance intake.
Step 5: Decide how you want to increase calories.
- Option A (direct): Increase your calories straight to that new maintenance number.
- Option B (gradual): Add half of the calories right away and the second half in week 2. This option works better for people who feel sudden scale jumps will mess with their heads.
Example
- Your average intake has been 1500 calories/day.
- You’ve been losing 1 lb/week.
- This means you’re currently in a 500-calorie deficit.
- Maintenance = 1500 + 500 = 2000 kcal/day.
Then just keep an eye on your average weight change and adjust your intake if:
- Weight is still trending down more than 0.5 % of your bodyweight per week → bump your calories up by 5–10 %.
- Weight is trending up more than 0.5% of your bodyweight per week → reduce your calories by 5 %.
Bottom line
Reverse dieting isn’t inherently harmful, but it’s important to understand what it can and can’t do. It won’t repair a broken metabolism (because your metabolism isn’t broken) or create a magical calorie-burning boost. For most people, transitioning directly to maintenance calories is a simpler, more efficient, and less painful approach to post-diet nutrition.
TL;DR:
What reverse dieting claims:
- Slowly increasing calories (50-100 kcal/week) after a diet will help “repair” your damaged metabolism, allow you to consume thousands more calories without gaining fat, and prevent weight regain.
The problem with these claims:
- Your metabolism isn’t “broken” – it adapts during weight loss and mostly recovers at maintenance
- You can’t boost metabolism beyond what’s expected for your body weight/composition
- The only way to significantly increase metabolism is to gain weight (muscle/fat)
Why it seems to work:
- People start tracking their intake accurately.
- A slow reverse diet approach keeps people in a deficit.
- A 50-100 kcal increase each week won’t show up on the scale as quickly as an immediate transition to maintenance. This avoids the rapid spike in scale weight, which can make it appear as though an individual isn’t gaining weight.
- A slow calorie increase provides structure at the end of a diet and prevents individuals from overshooting their new maintenance intake.
Better Approach:
- Calculate your new maintenance calories using your recent weight loss rate (calculator here).
- Jump directly to maintenance or do it over 2 weeks.
- Monitor your weight and adjust as needed. If you’re gaining more than 0.5% per week, reduce your intake by 5-10%. If you’re losing more than 0.5% per week, increase your intake by 5%.
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