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 mono-unsaturated 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. Am J Clin Nutr 2009; 90: 1632-41.