Substrate-energy metabolism and metabolic risk factors for cardiovascular disease in relation to fetal growth and adult body composition.

The effect of fetal programming on intermediary metabolism is uncertain. Therefore, we examined whether fetal programming affects oxidative and nonoxidative macronutrient metabolism and the prevalence of the metabolic syndrome in adult life. Healthy older men, aged 64-72 years, with either a lower birth weight (LBW, <or=25th %ile; n = 16) or higher birth weight (HBW, >or=75th %ile; n = 13) had measurements of 1) net oxidative metabolism using indirect calorimetry before and for 6 h after a mixed meal (3,720 kJ) and 2) postprandial oxidation of exogenous [13C]palmitic acid. Body composition was measured using dual-energy X-ray absorptiometry. After adjustment for current weight and height, the LBW group had a lower resting energy expenditure (REE) in the preprandial (4.01 vs. 4.54 kJ/min, P = 0.015) and postprandial state (4.60 vs. 5.20 kJ/min, P = 0.004), and less fat-free mass than the HBW group. The BW category was a significant, independent, and better predictor of REE than weight plus height. There were no significant differences between groups in net oxidative and nonoxidative macronutrient (protein, fat, carbohydrate) metabolism (or of exogenous [13C]palmitate) or in the prevalence of the metabolic syndrome, which was present almost twice as commonly in the LBW than in the HBW group. The study suggests that fetal programming affects both pre- and postprandial EE in older life by mechanisms that are at least partly related to the mass of the fat-free body. BW was found to be a significant predictor of REE that was independent of adult weight plus height.