Research

Hormonal

Obese, insulin-resistant individuals exhibit a defective (reduced) thermic effect of food, specifically for glucose, which may contribute to weight gain or impaired weight loss, though it cannot explain the majority of excess body weight.

If you are obese and insulin-resistant, your body may burn slightly fewer calories from food (50-150 kcal/day) than a lean person. While this makes weight loss slightly harder, it is not the main reason for obesity. Focus on sustainable caloric deficits and improving insulin sensitivity through exercise and diet quality rather than blaming a 'broken metabolism'.

GoodQualifiesMEDIUM confidence
The thermic effect of food is reduced in obese, insulin-resistant patients. The effect of thermogenesis represents about 50-150 kcal/day in such patients, and can explain only a minor part of their excess body weight.
Luc Tappy · annales de biologie animale biochimie biophysique · 1996

Why this rating

Based on multiple clinical studies cited, though results vary (some obese patients have normal TEF).

Source

Thermic effect of food and sympathetic nervous system activity in humans

Luc Tappy · annales de biologie animale biochimie biophysique · 1996

DOI 10.1051/rnd:19960405

narrative_reviewCited 226×
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DOI resolved against Crossref · corpus check 2026-06-10

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