Macro partitioning
The relationship between fat mass (FM) and fat-free mass (FFM) during weight change is consistent across sex and ethnicity, with a constant (C) of approximately 9.7, indicating that the proportion of weight lost as fat depends primarily on initial FM rather than demographic factors.
Your body's tendency to lose fat versus muscle during weight loss is determined by how much fat you currently have, not by whether you are a man or woman, or by your ethnicity. If you have more fat mass, you will lose a higher proportion of your weight as fat. This rule applies consistently across different demographic groups.
The FM–FFM relationship varied little by ethnicity (P= 0·57) or by sex (P= 0·26). The constant describing the FM– FFM relationship was estimated to be 9·7 (95 % CI 9.0, 10.3).
Why this rating
Large sample size (n=1953), rigorous statistical adjustment for BMI distribution, and replication of a seminal model.
Source
Consistency of fat mass–fat-free mass relationship across ethnicity and sex groups
Stephanie T. Broyles et al. · British Journal Of Nutrition · 2010
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