Can reverse dieting really trick your metabolism and prevent weight gain?

The promise of eating more and maintaining weight loss is alluring, but does reverse dieting really work? Experts weight in.

Reverse dieting often involves adding back 50 to 100 calories to your daily total each week — mostly in the form of protein.Getty Images

Losing weight (and keeping it off) is a tough nut to crack, especially since weight loss and maintenance is so unique to each individual.

But social media is abuzz with videos promoting a new way of eating that seems to turn dieting — and weight maintenance — on its head.

TikTok influencers call reverse dieting a way to “train your metabolism” to eat more food and not gain weight. It was popularized by bodybuilders who lose weight before a competition and then use this technique to return to their non-competition size gradually.

Certainly, the promise of eating more and maintaining weight loss is alluring, but does it work? Here’s what you need to know about reverse dieting, the science behind it and what experts gave to say.

What is reverse dieting?

Dr. Lilian de Jonge, associate professor at the department of nutrition and food studies at George Mason University, tells that reverse dieting often involves adding back 50 to 100 calories per day — mostly in the form of protein — in weekly steps. To put that into perspective, that’s roughly the number of calories in one-quarter of a cup of cottage cheese or a large hardboiled egg, so it’s not a huge increase in food.

In theory, reverse dieting can help you gradually liberalize your diet and find the calorie level where you can comfortably maintain your weight. However, at this point, there’s no scientific evidence that reverse dieting has any effect on your metabolism, and the practice has some drawbacks.

What happens to your metabolism when you lose weight?

Since reverse dieting is intended to counter the metabolic adaptations of strict dieting and weight loss, it helps to understand some metabolism basics.

As you lose weight, your metabolism adjusts to a smaller body. Suppose you used to weigh 200 pounds and you now weigh 175 pounds. It makes sense that you’d need fewer calories to maintain your lower body weight. But your body takes things a step further.

Evidence suggests that your body employs several adaptations after dieting. When you cut calories, your body senses you’re giving it less fuel, so your metabolism slows down to save energy. De Jong explains that this is an evolutionary response left over from when food was not abundantly available all year round. However, these days, food is readily available 24/7, so this creates a disadvantage. 

Our exercise routine also plays a role. Whether you’re exercising to lose weight or to stay fit, rigorous exercise may result in unknowingly trying to save energy during your non-workout hours — an adaptation known as constrained energy expenditure. This means that even if you’re burning 400 calories in a spin class, your overall calorie burn remains relatively constant because you might be taking things easy outside of your workout. So, on the days you work out, you might unconsciously spend more time sitting or you might opt for the escalator instead of the stairs, for example.

These conditions make it tough (but not impossible) to keep weight off, which is why the idea of reverse dieting is so appealing.

Does reverse dieting restore your metabolism?

There’s no evidence that it does. According to Dr. Robert Kushner, medical director of the Center for Lifestyle Medicine at Northwestern Medicine in Chicago, gradually reintroducing food after weight loss is a practical and standard approach used in both research studies and clinical practice. But the reason for doing this has to do with keeping an eye on the scale to make sure you’re maintaining — and not gaining — weight. As for tricking your metabolism? Without any proof, that’s a catchy spin, he says.

That said, reverse dieting may offer a potential benefit to your cardiometabolic health. This approach may help you avoid yo-yo dieting — the pattern of losing and regaining weight, which is associated with poorer cardiovascular health among women.

Can reverse dieting prevent regaining weight after weight loss?

Maybe. Keith-Thomas Ayoob, associate clinical professor emeritus in the department of pediatrics at Albert Einstein College of Medicine, points out that there’s a clinical trial in the works, but currently, there’s no scientific evidence on reverse dieting. “It doesn’t mean it won’t work, but finding out takes sound studies and time,” he says.

Following a strict weight-loss diet is tedious. “If you treat things as though the ‘diet is over’ and resume former eating habits, you’ll regain the weight, no question,” Ayoob says. Reverse dieting may be a way to prevent this from happening.

Kushner says that “after a period of dieting, slowly reintroducing more food makes sense because it helps you increase the variety of foods you eat and feel more in control while also assessing any weight changes.” So, if you see a bump in the scale when you eat more, you can decide if you want to reduce how much you’re eating or work on maintaining where you are. 

Are there benefits to reverse dieting?

Studies suggest that dieting to lose weight is associated with an increase in stress that takes a toll on your emotional and physical well-being. Therefore, by making your food choices feel less restrictive, reverse dieting might reduce the emotional impact of dieting. 

There’s also the possibility that reverse dieting will help normalize your appetite-regulating hormones. It’s easier to manage your weight if you’re not excessively hungry all the time. 

If you turned to unsustainable eating habits while losing weight, reverse dieting can help you discover a more realistic and enjoyable eating pattern while helping you to maintain a lower weight. But remember that these perks are all theoretical as there have been no scientific studies demonstrating the benefits of reverse dieting.

The bottom line

In order to prevent weight regain, it’s helpful to continue the behaviors that helped you lose weight, but that’s easier to do when you establish and practice healthy weight-loss tactics. If your diet is too restrictive, gradually increasing your calorie intake can be a successful (albeit tedious) strategy, but not necessarily because it’s hacking your metabolism. Instead, it’s more likely that it’s helping you identify the balance between an eating and exercise pattern that you can maintain

If you’re rigorously counting calories and checking the scale — because you’re dieting or reverse dieting — take note of the emotional impact of these behaviors, which can be stressful and triggering. Scale fluctuations are completely normal; they are due to factors like a heavy meal and water retention. However, if these small shifts upward impact your emotional wellbeing, you may want to reconsider reverse dieting, which focuses on calorie counting and assessing weight regain.

Reverse dieting (and intentional weight loss in general) is not advised if you’ve had a history of disordered eating or eating disorders. 

Finally, remember that weight loss is not just a matter of calories in-calories out as reverse dieting might suggest. Your body is complex, and there’s more to it than that. Also, it’s not necessary or advantageous to pursue thinness; healthy bodies come in a range of shapes and sizes.