If you’ve ever lost weight due to dieting or restricting your food intake, only to gain that weight back, you’ve likely experienced “weight cycling,” where your body size fluctuates up and down.

This doesn’t mean you “fail” at diets. People don’t fail diets; diets fail people. This is all related to how our bodies protect us and work their hardest to keep us healthy.

However, it can be defeating to see the number on the scale go down, only to see it go back up again. It may make you feel like a failure, like you did something wrong, or like you’re just meant to live in this seemingly endless cycle.

Aside from these all being lies that diet culture tells us, it’s also tied to science, and how dieting can actually cause us to gain weight over time. The diet mentality and weight gain go hand-in-hand, but it’s not your fault: it’s biological.

Luckily, you don’t need to stay stuck in this loop. By understanding why this happens, you can take the first step toward breaking it and stepping into healthier habits that support your physical and mental well-being.

Why Dieting Causes Weight Gain

While it may seem counterintuitive, dieting can lead to weight gain.

It’s not uncommon, and perhaps even very common, for people to experience weight fluctuations related to dieting. This constant back-and-forth, sometimes called “yo-yo-ing,” may make people feel like they are in an endless loop.

A person experiencing weight regain, or even gaining weight beyond their pre-diet body size, can be due to a wide variety of physiological and psychological factors.

For example, one study found that those who dieted had a higher likelihood of having a bigger body size than before they began their diet.¹

Among adolescent girls, self-reported dieting, exercise for weight control, and dietary restraint actually predict weight gain and the onset of obesity. This happens even among those who are initially not in larger bodies or underweight, a finding that has been replicated in several studies. ² ³ ⁴ ⁵1, 2, 3, 4

One study even concluded that in adolescents, weight-reduction efforts “are more likely to result in weight gain than in weight loss.”⁶

The long-term effects of dieting on weight may not keep the scale at a lower number, and in fact, can have the opposite effect.

The Impacts of Dieting on Metabolism

Regardless of what it’s called, all dieting involves some form of restriction, whether by removing certain foods, whole food groups, or limiting the amount of food eaten.

As we eat less, our bodies’ metabolism adapts, slowing down. Dieting and slowed metabolism impacts are not only short-term but can be lasting. When we end that period of restriction, our bodies’ metabolism is slowed, and they want to hold on to everything we eat to protect our health. This metabolic adaptation from dieting is just one of the reasons why weight regain is common following diets.

Perhaps one of the most notable examples is from the former reality show, “The Biggest Loser,” where contestants would over-exercise and restrict their food intake to see who could lose the highest percentage of body weight.

Despite the show’s inherently problematic nature, many of the contestants who lost significant amounts of weight regained it within a few years.

Researchers think this is likely because when people’s bodies are under stress from over-exercise and restriction, their metabolism slows for years — long after diets have ended.⁷

However, this isn’t exclusive to “The Biggest Loser.” Many people experience weight gain related to metabolic changes following a diet.

Dieting and Physical Hunger

Restriction can cause several physical and emotional reactions, including increasing hunger hormones.

Research found that weight loss related to calorie restriction, increased movement, and both combined, were linked with an increase in the “hunger hormone” ghrelin.⁸

One study on the unintended impacts of dieting noted that “dieting can lead to psychological distress, which in turn promotes disordered eating behaviors such as binge eating, purging, and other eating disorders.”⁹

In both male and female adolescents, dieting predicted increased binge eating and an increase in weight, leading the study to conclude: “In part, dieting may lead to weight gain via the long-term adoption of behavioral patterns that are counterproductive to weight management.”¹⁰

Another study linked the metabolic adaptation from dieting and weight loss with a greater drive to eat.¹¹

Combined, these factors can create real physical hunger, or “emotional hunger,” when a person has a stronger emotional desire to eat (more on that below).

The Scarcity Mindset and Emotional Hunger

In addition to causing physical hunger related to metabolism and hormones, dieting and restrictions can create an increased desire to binge eat, which can be psychological and emotional.¹²

At a base level, making “rules” about what you can or can’t have, rather than listening to your body’s natural hunger cues (whether physical or emotional) and what you want, can increase the desire for it. When you finally do allow yourself to have it, because you’ve deprived yourself for so long, you may be more likely to binge.

This can make you feel worse, and people may try to compensate for that binge with more restriction, creating an endless cycle of restrictive dieting and weight cycling, emotional and physical hunger, and bingeing.

The Harmful Impacts of Weight Cycling

Fluctuations in body weight are normal to some degree, especially through different seasons or phases of life as our bodies go through changes.

However, intentionally losing weight and gaining it back, especially repeatedly, can have longstanding and harmful impacts on our bodies—and cause emotional stress.

One study found that after we lose weight, our bodies naturally compensate by “overshooting” from our pre-diet weight. Meaning, that if you’ve ever ended a diet and gained weight beyond your pre-diet body, it’s a natural biological response as your body fights to protect your health.¹³

This is where that endless loop comes in, with many feeling like they’ve “failed” diets. However, this is a natural biological response as our bodies fight to protect us.

Research shows that weight cycling can negatively impact blood pressure, heart rate, sympathetic activity, blood sugar levels, lipids, and insulin.¹⁴

It can also cause fluctuations in fat deposits across the cycles of restriction and non-restriction, which harm our bodies and muscle mass. It can also cause fat cells to increase the production of inflammation markers. As it causes glucose fluctuations, it can also cause stress on our pancreas and the related systems.¹⁵

While it may seem harmless, weight cycling can put a lot of long-term stress on our bodies.

How to Break Free From Diet Cycles and Embrace Food Freedom

If you’ve found yourself in an endless loop of dieting on and off again, you don’t have to live that way. You don’t have to keep wondering why dieting causes weight gain and then jump into another diet that won’t serve your long-term health.

It’s possible to make peace with food and eat in a way that nourishes your health inside and out — without falling victim to the next new diet that promises to be the end-all, be-all.

Schedule an appointment with Life Cycle Nutrition to empower your health and break away from the world of dieting. We’re here to walk through the journey with you.

 

Works Cited:

• Siahpush, Mohammad, Melissa Tibbits, Raes A. Shaikh, Gopal K. Singh, Asia S. Kessler, and Terry T. Huang. 2015. “Dieting Increases the Likelihood of Subsequent Obesity and BMI Gain: Results from a Prospective Study of an Australian National Sample.” International Journal of Behavioral Medicine 22, no. 5 (October): 662-671. https://doi.org/10.1007/s12529-015-9463-5.
• Neumark-Sztainer, Dianne, Melanie Wall, Jess Haines, Mary Story, and Marla E. Eisenberg. 2007. “Why does dieting predict weight gain in adolescents? Findings from project EAT-II: a 5-year longitudinal study.” Journal of the American Dietetic Association 107, no. 3 (March): 448-455. https://doi.org/10.1016/j.jada.2006.12.013.
• Neumark-Sztainer, Dianne, Melanie Wall, Mary Story, and Amber R. Standish. 2012. “Dieting and unhealthy weight control behaviors during adolescence: associations with 10-year changes in body mass index.” Journal of Adolescent Health 50, no. 1 (January): 80-86. https://doi.org/10.1016/j.jadohealth.2011.05.010.
• Stice, E., R P Cameron, J D Killen, C. Hayward, and C B Taylor. 1999. “Naturalistic weight-reduction efforts prospectively predict growth in relative weight and onset of obesity among female adolescents.” Journal of Consulting and Clinical Psychology 67, no. 6 (December): 967-974. https://doi.org/10.1037//0022-006x.67.6.967.
• Field, Alison E., S B Austin, C B Taylor, Susan Malspeis, Bernard Rosner, Helaine R. Rockett, Matthew W. Gillman, and Graham A. Colditz. 2003. “Relation between dieting and weight change among preadolescents and adolescents.” Pediatrics 112, no. 4 (October): 900-906. https://doi.org/10.1542/peds.112.4.900.
• Stice et al., “Naturalistic Weight-Reduction Efforts,” 967–74.
• Hall, Kevin D. 2022. “Energy compensation and metabolic adaptation: “The Biggest Loser” study reinterpreted.” Obesity 30, no. 1 (January): 11-13. https://doi.org/10.1002/oby.23308.
• Jin, Zhuoxiu, Jiajin Li, Alice E. Thackray, Tonghui Shen, Kevin Deighton, James A. King, and David J. Stensel. 2025. “Fasting appetite-related gut hormone responses after weight loss induced by calorie restriction, exercise, or both in people with overweight or obesity: a meta‐analysis.” International Journal of Obesity volume 49 (February): 776-792. https://doi.org/10.1038/s41366-025-01726-4.
• Habib, Ashna, Tooba Ali, Zainab Nazir, Arisha mahfooz, Qurat-ul-Ain Inayat, and Ariful Haque. 2023. “Unintended consequences of dieting: How restrictive eating habits can harm your health.” International Journal of Surgery Open 60 (November). https://doi.org/10.1016/j.ijso.2023.100703.
• Neumark-Sztainer et al., “Why Does Dieting Predict Weight Gain,” 448–55.
• Martins, Catia, Jessica A. Roekenes, Jens F. Rehfeld, Gary R. Hunter, and Barbara A. Gower. 2023. “Metabolic adaptation is associated with a greater increase in appetite following weight loss: a longitudinal study.” The American Journal of Clinical Nutrition 118, no. 6 (December): 1192-1201. https://doi.org/10.1016/j.ajcnut.2023.10.010.
• Polivy, Janet, and Peter C. Herman. 1985. “Dieting and binging: A causal analysis.” American Psychologist 40 (2): 193-201. https://doi.org/10.1037/0003-066X.40.2.193.
• Dulloo, A G, J. Jacquet, J-P Montani, and Y. Schutz. 2015. “How dieting makes the lean fatter: from a perspective of body composition autoregulation through adipostats and proteinstats awaiting discovery.” Obesity Reviews 16, no. 1 (February): 25-35. https://doi.org/10.1111/obr.12253.
• Rhee, Eun-Jung. 2017. “Weight Cycling and Its Cardiometabolic Impact.” Journal of Obesity & Metabolic Syndrome 26, no. 4 (December): 237-242. https://doi.org/10.7570/jomes.2017.26.4.237.
• Wang, Huan, Wenbi He, Gaoyuan Yang, Lin Zhu, and Xiaoguang Liu. 2024. “The Impact of Weight Cycling on Health and Obesity.” Metabolites 14, no. 6 (June). https://doi.org/10.3390/metabo14060344.