Background: It is unclear from the inconsistent epidemiologic evidence whether dietary fat intake is associated with future weight change.
Objective: The objective was to assess the association between the amount and type of dietary fat and subsequent weight change (follow-up weight minus baseline weight divided by duration of follow-up).
Design: We analyzed data from 89,432 men and women from 6 cohorts of the EPIC (European Prospective Investigation into Cancer and Nutrition) study. Using country-specific food-frequency questionnaires, we examined the association between baseline fat intake (amount and type of total, saturated, polyunsaturated, and monounsaturated fats) and annual weight change by using the residual, nutrient density, and energy-partition methods. We used random-effects meta-analyses to obtain pooled estimates across centers.
Results: Mean total fat intake as a percentage of energy intake ranged between 31.5% and 36.5% across the 6 cohorts (58% women; mean +/- SD age: 53.2 +/- 8.6 y). The mean (+/-SD) annual weight change was 109 +/- 817 g/y in men and 119 +/- 823 g/y in women. In pooled analyses adjusted for anthropometric, dietary, and lifestyle factors and follow-up period, no significant association was observed between fat intake (amount or type) and weight change. The difference in mean annual weight change was 0.90 g/y (95% CI: -0.54, 2.34 g/y) for men and -1.30 g/y (95% CI: -3.70, 1.11 g/y) for women per 1 g/d energy-adjusted fat intake (residual method).
Conclusions: We found no significant association between the amount or type of dietary fat and subsequent weight change in this large prospective study. These findings do not support the use of low-fat diets to prevent weight gain.