After losing weight through dieting, the body continues to burn fewer calories than expected based on the new lower weight, creating an extra daily energy deficit of about 100 kcal that may make it...
Mechanism
Synthesis from 1 study
After losing weight by eating less, your body burns fewer calories than expected because your organs slow down, your core temperature drops, and your muscles become more efficient at moving — all triggered by falling hormone levels from dieting (10.1002/oby.23703). These changes stick around even...
Most probable mechanism
After losing weight by eating less, the body burns fewer calories than expected, even after stopping weight loss, because organs like the liver and kidneys slow down their activity, core body temperature drops, and muscles become more efficient at moving — all of which reduce energy use. These changes are triggered by falling levels of insulin, glucagon, leptin, and thyroid hormone, and they persist during weight maintenance, creating a persistent calorie deficit that makes it harder to keep weight off (10.1002/oby.23703).
Caloric restriction lowers plasma insulin and raises glucagon, triggering glycogen depletion and loss of bound intracellular water, which reduces the metabolic demand of tissues (10.1002/oby.23703).
Depleted glycogen shifts energy use to fat breakdown, which is associated with reduced metabolic activity in high-energy organs including the liver, kidneys, and heart, as shown by decreased urea production, glomerular filtration rate, and heart rate (10.1002/oby.23703).
Core body temperature decreases due to reduced metabolic output from organs and diminished sympathetic drive, lowering the energy required to maintain homeostasis (10.1002/oby.23703).
Weight loss reduces leptin and triiodothyronine levels, which suppresses sympathetic nervous system activity, leading to improved skeletal muscle mechanical efficiency during daily movement and reduced energy expenditure during nonresting activities (10.1002/oby.23703).
The combined reduction in organ metabolic rates and improved muscle efficiency results in a persistent, mass-independent drop in resting and nonresting energy expenditure that continues during weight maintenance, contributing approximately 40–60 kcal/day from organ changes and additional reductions from muscle efficiency (10.1002/oby.23703).
Evidence from Studies
Supporting (1)
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Changes in body composition and homeostatic control of resting energy expenditure during dietary weight loss
Contradicting (0)
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Gold Standard Evidence Needed
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