What causes weight regain after dieting?

Breaking the Cycle: The Truth about On-Off Dieting

With the world's growing obsession with weight loss and the pressure to fit into socially accepted standards for what it means to be an ‘athlete’, many people fall into the cycle of on-off dieting. This phenomenon, where individuals repeatedly lose and regain weight, has become a significant concern among nutritionists and health experts. Through comprehensive research, it has become clear that this dieting trend may be doing more harm than good.

The problem with yo-yo dieting

Two studies by Outland (2018) and Roybal (2005) discovered that yo-yo dieting has a direct association with harmful metabolic changes. These changes can further lead to health risks like type 2 diabetes, especially in overweight individuals. Another startling revelation by Warnert (2004) and Evans-Molina (2011) is that this form of dieting might actually increase weight gain over time.

Moreover, when people enter extreme diets, their resting metabolic rate and energy expenditure decrease due to a loss in lean body mass, with many studies confirming this phenomenon (Wilson 1990, Fox 2019, and Souza 2022). This means it becomes increasingly harder to shed those extra pounds and far easier to regain them. Over time, as people continue with this pattern, their metabolism starts defending against weight loss even more robustly.

Outland’s 2018 study pointed out that during these repetitive diet cycles, the body triggers “compensatory reactions”. Essentially, the body will slow down its metabolism to prevent the loss of fat stores. It's a survival mechanism. The human body perceives prolonged dieting as a threat and becomes exceptionally efficient in conserving energy, hence making weight loss more challenging. As aptly put by Zuger in 2009, “losing weight is hard, but keeping it off is harder”.

This is why it’s crucial to prioritize strength training and adhere to the appropriate macronutrient balance when in a caloric deficit. This ensures muscle preservation, preventing a metabolic slowdown which can lead to the pitfalls of yo-yo dieting.

The Influence of the Diet Industry

According to Joanne Ikeda, a nutrition specialist at UC Berkeley, dieting isn't the solution to obesity.

After surveying 149 women, she found that many had gone through more than 11 cycles of dieting.

These repeated efforts often result in them gaining more weight than they originally lost. The enormous $30-billion diet industry perpetuates this myth of the “perfect diet”, causing individuals to fall into the yo-yo diet trap.

Ikeda emphasizes the need to shift the focus from losing weight to maintaining a healthy lifestyle. She suggests an intake of about 1,800 calories per day from nutrient-dense foods coupled with regular exercise.

A Biological Perspective

A recent study by Sumithran and colleagues in 2011 delved into the hormonal regulation of body weight. Their findings revealed that voluntary weight loss activates various biological and compensatory mechanisms that push the body to regain weight.

Post weight loss, hormones that suppress appetite like leptin, peptide YY, and cholecystokinin remained low, while those promoting hunger and energy storage, like ghrelin and GIP, stayed high. This hormonal imbalance leads to prolonged feelings of hunger, making sustained weight loss a challenge.

So if you’ve ever come off an extreme diet and just wanted to spend the next day bingeing on chocolate and donuts, you’ve probably experienced this before.

Something new to try

My question to you is this, if you’ve tried every diet under the sun and nothing seems to be working, then have you tried not trying? This may sound counter-intuitive, but more often than not, research has evidence that dieting only leads to weight gain for those that can’t control their appetite following a restrictive cycle of dieting.

Traditional diets that restrict energy to induce weight loss typically show patterns of weight regain, and can promote increased food preoccupation, loss of control and overeating.

Eating in response to hunger and satiety signals, termed intuitive eating, has been promoted as an alternative to deliberate energy restriction. Intuitive eating is a key recommendation of the non-dieting and Health at Every Size approaches, which advocate a shift in focus away from body weight to the improvement of health behaviours and wellbeing.

Perhaps a change in mindset to weight maintenance rather than weight loss may be the answer here.

Takeaways

The mounting evidence against yo-yo dieting is a clear sign that individuals should prioritize long-term health over short-lived weight loss goals. The body’s intricate and powerful compensatory reactions make it essential to approach weight loss holistically, focusing on metabolic health, exercise, sleep, and intuitive eating. Only by understanding and respecting our body's mechanisms can we hope to achieve and maintain a healthy weight.

Resources

Lauren Outland, DrPH, WHNP
Evidence-based Ways to Promote Metabolic HealthPublished:April 18, 2018DOI:https://doi.org/10.1016/j.nurpra.2018.02.010

Roybal, Donna J.. “Is "Yo-Yo" Dieting or Weight Cycling Harmful to One's Health? - eScholarship.” (2005).

Warnert, Jeannette. “Yo-yo dieting drives up obesity.” California Agriculture 58 (2004): 11-11.

Carmella Evans-Molina, Yo-Yo Dieting: Biology or Behavior?.Sci. Transl. Med.3,108ec180-108ec180(2011).DOI:10.1126/scitranslmed.3003403

Aline de Souza, Hong Ji, Kyle Korolowicz, Olga Rodriguez, Chris Albanese, Carolyn Ecelbarger, Kathryn Sandberg, Yo-Yo Diet Has Adverse Effects on Cardiac Function and Insulin Sensitivity in Female Fischer Rats, 13 May 2022, https://doi.org/10.1096/fasebj.2022.36.S1.R5866