Why losing weight sometimes doesn't work: hormones, stress, and the set point

Losing weight is, however, more complex than merely consuming fewer calories. The body has mechanisms that regulate weight. Hormones, stress, and biological adaptations play a significant role in this process. In this article, you will discover why maintaining weight loss can sometimes be challenging and what this implies for achieving healthy weight loss.

Losing weight is about more than just eating less

The foundation of weight loss appears straightforward: consuming fewer calories than you burn results in weight loss. However, research indicates that the body adapts as weight is lost.

When you lose weight:

• energy consumption decreases
• the hormone balance changes
• the body adjusts fat burning

This is also referred to as metabolic adaptation. The body attempts to conserve energy and maintain its previous weight. This is not a matter of lacking discipline but rather a biological defence mechanism. When the body biologically adapts to weight loss, the process can become more complex than merely eating less and exercising more.

The role of the set point: why the body wants to maintain weight

The body has mechanisms that aim to maintain weight within a certain range. This concept is often referred to as the so-called set point theory.

After weight loss, several processes may occur:

• the satiety hormone leptin decreases
• the hunger hormone ghrelin increases
• the resting metabolism decreases

Research indicates that these hormonal changes can persist for a prolonged period. Consequently, the body continues to send signals designed to conserve energy and boost appetite. This can make it more difficult to lose further weight or to maintain the new weight.

In cases of overweight or obesity, these biological processes may play a more significant role in maintaining or regaining weight, although this effect varies from individual to individual.

Hormones that influence weight and appetite

Weight is partly regulated by the interaction of hormones.

Leptin: the satiety signal

Leptin is produced by fat cells and informs the brain about the amount of energy stored in the body. When the fat percentage decreases, leptin levels also drop. This can lead to increased feelings of hunger and a reduction in energy expenditure.

This mechanism explains why one often feels less satiated after losing weight than beforehand.

Ghrelin: the hunger hormone

Ghrelin is produced in the stomach and stimulates appetite. Following weight loss, ghrelin levels may rise, making it more challenging to consume less. This effect can persist for a prolonged period.

Insulin and fat storage

Insulin plays a crucial role in the absorption and storage of energy. In cases of insulin resistance, the body becomes less responsive to insulin. This condition is more commonly observed in individuals who are overweight. Consequently, the regulation of blood sugar levels and energy balance may be altered. This can impact weight management and make losing weight more challenging, although the extent of this varies between individuals.

Stress and weight: what does cortisol do?

Prolonged stress can affect weight. During stress, the body produces more cortisol. This hormone can:

• affect appetite
• increase the preference for energy-rich foods
• promote fat storage around the abdomen

In addition, stress can negatively impact sleep quality. Poor sleep, in turn, influences leptin and ghrelin levels, which may lead to increased hunger and appetite.

Stress management and adequate rest are therefore important components of healthy weight loss.

Why weight often returns after a diet

In practice, it seems that many people regain weight after a period of strict dieting. A temporary diet is often challenging to sustain, particularly when it significantly differs from regular eating habits.

This explains why:

• Strict dieting often yields temporary results.
• Old eating habits may gradually resurface over time.
• Achieving long-term weight stability can be challenging without sustainable changes.

They are not a replacement for a healthy lifestyle but can serve as a supplement in certain circumstances where previous efforts have produced insufficient results.

What does this mean for healthy weight loss?

Healthy weight loss revolves around an approach that takes the body’s physiology into account. That means, among other things:

• food that provides sufficient satiety (e.g., high in protein and fibre)
• regular mealtimes
• adequate sleep
• attention to stress
• sustainable lifestyle changes instead of extreme dieting

For some individuals, professional guidance may be appropriate, for instance, when lifestyle adjustments prove insufficiently effective or when obesity is linked to health risks.

The role of modern medication in weight loss

In recent years, medications have been developed to target the hormonal regulation of appetite. GLP-1 medications, such as semaglutide or tirzepatide (for example, Mounjaro), influence signals related to satiety and hunger.

These resources can:

• reduce the sensation of hunger
• enhance feelings of fullness
• support weight loss

They are not a replacement for a healthy lifestyle but can serve as a supplement in specific circumstances where previous efforts have produced insufficient results.

When might it be wise to seek assistance?

It may be beneficial to consider professional support if:

• you repeatedly lose weight only to regain it
• your BMI is raised, leading to increased health risks
• lifestyle changes prove to have insufficient impact
• you find the process increasingly mentally taxing

Support can be beneficial when weight loss is impeded by biological processes, lifestyle factors, or a combination of the two.

Conclusion

Would you like to know what treatment options are available if losing weight despite your efforts is unsuccessful?