Research

Energy balance

Approximately two-thirds of the variability in Body Mass Index (BMI) among individuals within the same population is attributable to genetic factors rather than environmental differences.

Your body weight is heavily influenced by your genetics (about 67% of the variation). This means standard 'eat less, move more' advice may be less effective for you than for others because your biology fights back. Focus on environmental changes (like access to healthy food) and targeted therapies rather than just blaming yourself for lack of willpower.

GoodSupportsHIGH confidence
Studies of twins reared apart indicate that approximately two-thirds of the variability in BMI can be attributed to genetic factors
Éric Ravussin et al. · British Journal Of Nutrition · 2000

Why this rating

Based on multiple large-scale twin studies (Finnish, Japanese, American) with consistent high heritability estimates (0.61-0.85).

Source

Energy balance and weight regulation: genetics versus environment

Éric Ravussin et al. · British Journal Of Nutrition · 2000

DOI 10.1017/s0007114500000908

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

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