Objective: To study the effect to recommend no snacks vs three snacks per day on 1-year weight loss. The hypothesis was that it is easier to control energy intake and lose weight if snacks in between meals are omitted. Subjects/Method: In total 140 patients (36 men, 104 women), aged 18-60 years and body mass index430 kg/m 2 were randomized and 93 patients (27 men, 66 women) completed the study. A 1-year randomized intervention trial was conducted with two treatment arms with different eating frequencies; 3 meals/day (3M) or 3 meals and 3 snacks/day (3 þ 3M). The patients received regular and individualized counseling by dieticians. Information on eating patterns, dietary intake, weight and metabolic variables was collected at baseline and after 1 year. Results: Over 1 year the 3M group reported a decrease in the number of snacks whereas the 3 þ 3M group reported an increase (À1.1 vs þ 0.4 snacks/day, respectively, Po0.0001). Both groups decreased energy intake and E% (energy percent) fat and increased E% protein and fiber intake but there was no differences between the groups. Both groups lost weight, but there was no significant difference in weight loss after 1 year of treatment (3M vs 3 þ 3M ¼ À4.176.1 vs À5.979.4 kg; P ¼ 0.31). Changes in metabolic variables did not differ between the groups, except for high-density lipoprotein that increased in the 3M group but not in 3 þ 3M group (Po0.033 for group difference). Conclusion: Recommending snacks or not between meals does not influence 1-year weight loss.