Rattikan Sumpao¹, Preeya Leelahagul¹, Siriporn Tuntipopipat², Thanwarin Tangsermwong³, Chawanphat Chawanphat², Wutarak Puengputtho¹, Kemika Praengam², Surat Komindr^4,

Low glycemic index medical food (LGI) has been utilized as a meal replacement for patients with type 2 diabetes, obesity, and improving other metabolic outcomes. However, since the impact of this diet on hormones and satiety is unclear, this study determined the effect of a novel LGI on satiety and gut hormone responses in normal-weight and obese adults. Methods: The study was a randomized, cross-over, single-blind controlled trial. Healthy adults aged 20–45 years consisting of 20 normal weight (NW) and 20 obese (OB) as classified by % body fat. Each subject was assigned to drink the soybean milk (SB) as a control and the novel LGI breakfast (ONCE PRO^Ⓡ) as a test meal in a random order, with a seven-day washout period. Their satiety was assessed with a visual analog scale (VAS) questionnaire before and every 30 minutes after each breakfast for 240 minutes. Plasma GLP-1, ghrelin, and total PYY were measured at baseline, 30, 60, 120, and 240 minutes after breakfast. After 240 minutes, subjects were given a buffet lunch to eat until satiated and total lunch intake was recorded. Results: Both NW and OB had significantly higher GLP-1 and PYY AUCs and significantly lower ghrelin AUCs (both NW and OB; GLP-1 p<0.0001, PYY p<0.01, and ghrelin p<0.001) after the novel LGI compared to SB, which were related to the satiety and hunger scores. After the novel LGI, both groups rated themselves as less hungry and fuller than SB. Moreover, ghrelin AUC of OB was significantly lower than NW (p < 0.05) after consuming the novel LGI which was related to a significantly lower hunger score (p < 0.05) and a tendency to eat less lunch than after SB. Conclusions: The novel low glycemic index medical food had superior effects on gut hormones and satiety improvement over soybean milk in both NW and OB subjects. Furthermore, OB tended to be more influenced by the novel LGI than NW on the hormonal changes and decreased eating.

low glycemic index, meal replacement, satiety, glucagon-like peptide 1, ghrelin, peptide YY