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 index>30 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+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+3M group reported an increase (-1.1 vs +0.4 snacks/day, respectively, P<0.0001). 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+3M=-4.1+/-6.1 vs -5.9+/-9.4 kg; P=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+3M group (P<0.033 for group difference).
Conclusion: Recommending snacks or not between meals does not influence 1-year weight loss.