Research

Energy balance

Overfeeding healthy young men of normal body weight does not trigger significant energy-wasting mechanisms (like adaptive thermogenesis); instead, 85-90% of excess energy intake is deposited as body mass.

If you are a healthy young man, your body does not have a strong 'safety valve' to burn off excess calories. If you consistently eat 1000 calories more than you need, 85-90% of those extra calories will be stored as body mass. Do not rely on your body to naturally adjust its metabolism to prevent weight gain.

GoodRefutesHIGH confidence
There was no evidence of a significant energy-wasting mechanism in this study... on average, 85% to 90% of the excess energy intake provided during overfeeding was deposited.
Susan B. Roberts · Obesity Research · 1995

Why this rating

Based on a controlled metabolic study using doubly labeled water and indirect calorimetry.

Source

Abnormalities of Energy Expenditure and the Development of Obesity

Susan B. Roberts · Obesity Research · 1995

DOI 10.1002/j.1550-8528.1995.tb00458.x

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DOI resolved against Crossref · corpus check 2026-06-10

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