Maternal high-protein/low-glycemic-index diet during pregnancy impairs offspring lipid profile–a randomized controlled trial

Purpose We aimed to investigate the effects of a high protein content and a low glycemic index (HPLGI) diet during pregnancy on offspring body composition and metabolic health at 9 years of age. Methods We conducted a randomized controlled trial in pregnant women with a pre-pregnancy BMI of 28–45 kg/m 2 who were randomly assigned to either an HPLGI diet or a moderate-protein, moderate-glycemic-index (MPMGI) diet. Of the 208 live-born offspring, 114 were followed up at 9 years of age. Offspring blood samples were collected following an overnight fast, and continuous glucose monitoring data were obtained for up to 14 days. Body composition was assessed using dual-energy X-ray absorptiometry and magnetic resonance imaging. Results Offspring in the HPLGI group exhibited 0.30 mmol/L ( P = 0.033) higher total cholesterol, 0.24 mmol/L ( P = 0.031) higher LDL-cholesterol, and 0.03 g/cm 2 ( P = 0.017) higher bone mineral density than those in the MPMGI group. LDL-cholesterol trajectories from birth to 9 years of age indicated that group differences in LDL-cholesterol increased with age and manifested later in life. Glucose homeostasis and adipose tissue mass did not differ significantly between groups. Conclusion An HPLGI diet during pregnancy may negatively affect offspring total cholesterol and LDL-cholesterol. This underscores the need to investigate the long-term consequences of high-protein diets and the underlying mechanisms.