Background:The extent of weight change is varied for specific foods. This highlights the effect of dietary quality and food choices on weight control.Objectives:The aim of this study was to examine the association between alterations in food group intake and weight change over a 3 years follow-up period.Materials and Methods:This longitudinal study was conducted on 851 adults in the framework of Tehran Lipid and Glucose Study. Intakes of various foods were measured at baseline and after 3 years using a validated semi-quantitative food frequency questionnaire. Dietary data was grouped into 13 food groups. Alterations in food group intakes were categorized in tertiles; middle tertile of intake changes was considered as the reference category and the first and last tertiles of changes as increased and decreased intakes, respectively. Weight change per year of follow-up was the outcome of interest. Weight gain was defined as ≥ 0.5 kg/y, weight loss as ≤ -0.5 kg/y and stable weight as > -0.5 to < 0.5 kg/y. Multinomial logistic regression was used with stable weight as the reference group.Results:In men, weight loss was significantly predicted only by decreased intake of added sugars (OR: 2.21, 95% CI: 1.06-4.63). In women, weight gain was significantly predicted by decreased intake of whole grains (OR: 1.92, 95% CI: 1.11-3.31) and weight loss was predicted by decreased intake of vegetables (OR: 0.44, 95% CI: 0.21-0.91).Conclusions:Alterations in consumption of whole grains, vegetables, and added sugars are associated with body weight change, suggesting that it could be helpful in weight control.