What is the reason for not losing weight after 15 days of fasting

Not losing weight after 15 days of fasting may be related to factors such as decreased basal metabolic rate, water retention, muscle loss, unreasonable dietary structure, and the body entering a protective mode. Long term fasting can lead to reduced energy expenditure, decreased fat breakdown efficiency, and may even pose health risks.

1. Decreased basal metabolic rate

Long term fasting triggers the body's self-protection mechanism, reducing basal metabolic rate to decrease energy expenditure. When calorie intake is consistently insufficient, thyroid hormone levels decrease, leading to a slowdown in metabolic rate. In this situation, even if eating is reduced, weight may stagnate or even rebound.

2. Water retention

Electrolyte imbalance during fasting may lead to water retention, masking the effect of fat reduction. The imbalance of sodium potassium ratio can promote the body to store more water, resulting in a constant weight figure. Some people may experience edema during the later stages of fasting, which is closely related to hormonal changes.

3. Muscle loss

When protein intake is insufficient, the body will break down muscle tissue to provide energy. Muscle density is greater than fat, resulting in greater weight for the same volume. Although there is a decrease in fat, muscle loss may lead to less noticeable weight changes. A decrease in muscle mass will further lower basal metabolism.

4. The diet structure is unreasonable

If too much refined carbon water or high salt food is taken when resuming eating, it is easy to cause blood sugar fluctuation and water retention. Some people overeat after fasting, and their actual calorie intake exceeds their expenditure, leading to the re accumulation of fat. Unscientific refeeding methods can affect weight loss outcomes.

5. The body enters a protective mode.

Long term fasting can make the body mistakenly believe it is in a state of famine and actively reduce the efficiency of fat breakdown. The decrease in leptin levels and the increase in ghrelin levels result in a predisposition to obesity. This metabolic adaptation phenomenon is more common in extreme cannibal populations and requires professional nutritional intervention to break the plateau period.

It is recommended to adopt scientific weight loss methods, control intermittent fasting within a reasonable range, and maintain muscle mass with strength training. Ensure daily intake of high-quality protein, choose low glycemic index foods, and supplement with sufficient vitamins and minerals. Regular monitoring of body fat percentage is more meaningful than simply focusing on weight. When metabolic abnormalities occur, timely consultation with the nutrition department is necessary to establish sustainable eating and exercise habits for healthy weight loss. Extreme fasting may damage basic metabolic functions.