Background: There is a lack of appetite studies in free-living subjects supplying the habitual diet with either sucrose or artificially sweetened beverages and foods. Furthermore, the focus of artificial sweeteners has only been on the energy intake (EI) side of the energy-balance equation. The data are from a subgroup from a 10-wk study, which was previously published.

Objective: The objective was to investigate changes in EI and energy expenditure (EE) as possible reasons for the changes in body weight during 10 wk of supplementation of either sucrose or artificial sweeteners in overweight subjects.

Design: Supplements of sucrose-sweetened beverages and foods (2 g/kg body weight; n = 12) or similar amounts containing artificial sweeteners (n = 10) were given single-blind in a 10-wk parallel design. Beverages accounted for 80% and solid foods for 20% by weight of the supplements. The rest of the diet was free choice. Indirect 24-h whole-body calorimetry was performed at weeks 0 and 10. At week 0 the diet was a weight-maintaining standardized diet. At week 10 the diet consisted of the supplements and ad libitum choice of foods. Visual analog scales were used to record appetite.

Results: Body weight increased in the sucrose group and decreased in the sweetener group during the intervention. The sucrose group had a 3.3-MJ higher EI but felt less full and had higher ratings of prospective food consumption than did the sweetener group at week 10. Basal metabolic rate was increased in the sucrose group, whereas 24-h EE was increased in both groups at week 10. Energy balance in the sucrose group was more positive than in the sweetener group at the stay at week 10.

Conclusion: The changes in body weight in the 2 groups during the 10-wk intervention seem to be attributable to changes in EI rather than to changes in EE.