Application of personalized nutrition counseling according to glycemic response in obese adults: A randomized dietary intervention study

This randomized clinical trial was conducted to investigate the effects of personalized nutrition counseling according to blood glucose response and dietary intake, which can be measured using a flash continuous glucose monitoring (CGM) device, on weight changes and eating habits in obese adults. The participants of this study comprised obese adults over 30 years of age, which were randomly assigned to either the (1) personalized nutrition group (PN) or (2) control group (CON) with a study period of up to 12 weeks. Body weight, body mass index, body fat mass, body fat percentage, and waist-to-hip ratio significantly decreased in the PN group when compared with the CON group (P < 0.05; P < 0.01). Based on the findings of the flash CGM, the PN group showed a significant decrease in both blood glucose levels, hemoglobin A1c (HbA1c), and time above range (P < 0.05). The levels of blood HbA1c and insulin were significantly decreased in both groups, but the PN group showed a greater decrease (HbA1c, P = 0.000; insulin, P = 0.000) than the CON group did (HbA1c, P = 0.001; insulin, P = 0.001). The blood triglyceride levels were significantly lowered only in the PN group (P = 0.026). It was confirmed that personalized nutrition counseling using a flash CGM device was effective in reducing body weight, abdominal fat, and blood HbA1c, insulin, and triglyceride levels and improving meal quantity and eating habits in obese adults.