Differential effects of nutritive and non-nutritive sweet mouth rinsing on appetite in adults with obesity

Excessive added sugar intake has been associated with obesity; however, the effect of dietary sweetness on energy intake (EI) and appetite in adults with and without obesity has not yet been determined. To assess the effect of mouth rinses with and without energy and sweetness on measures of appetite, and to compare responses between subjects with body mass index (BMI) between 18.5 and 24.9 kg/m2 or ≥30 kg/m2. In this randomized, double-blind crossover study, 39 subjects (age 23±5y; 17 male, 22 female; BMI 18.5–24.9 kg/m2: n = 21; ≥30 kg/m2: n = 18) performed modified sham-feeding (MSF) with a mouth rinse containing either sucrose, sucralose, maltodextrin, or water for 2min before expectorating the solution. Blood sampling and subjective appetite assessments occurred at baseline (−5) and 15, 30, 60, and 90min post-MSF. After, EI was assessed at a buffet meal and post-meal appetite ratings were assessed hourly for 3h. Post-MSF ghrelin increased for water vs. maltodextrin (water: p = 0.03). Post-MSF cholecystokinin increased following maltodextrin-MSF (p = 0.03) and sucralose-MSF (p = 0.005) vs. sucrose for those with BMI:18.5–24.9 kg/m2 only. There was greater post-MSF desire to eat in response to water vs. sucrose (p = 0.03) and reduced fullness with sucralose for those with BMI≥30 vs. 18.5–24.9 kg/m2 (p < 0.001). There was no difference in EI at the buffet meal by mouth rinse (p = 0.98) or by BMI (p = 0.12). However, there was greater post-meal fullness following sucralose-MSF vs. water (p = 0.03) and sucrose (p = 0.004) for those with BMI≥30 vs. 18.5–24.9 kg/m2. Sucralose rinsing led to greater cephalic phase CCK release in adults with a BMI:18.5–24.9 kg/m2 only; however, ghrelin responses to unsweetened rinses were energy-specific for all adults. As subsequent EI was unaffected, further investigation of cephalic phase appetite is warranted.