Impact of high- and moderate-protein supplementation on early-life obesity and body composition: a randomized controlled trial in India.
BACKGROUND: Complementary feeding is vital for meeting infants' nutritional needs. In low-to-middle-income countries (LMICs), limited dietary diversity often leads to inadequate protein intake, contributing to growth faltering. Conversely, excessive intake may increase risk of early-life obesity, but evidence on the optimal balance remains limited. OBJECTIVES: This study aimed to measure the effects of micronutrient-fortified, isocaloric high- and moderate-protein supplementation in infants aged 6-12 mo on overweight and/or obesity [body mass index (BMI)-for-age z-scores (BMIz) >2 SD] and body composition, that is, fat mass (FM), fat-free mass (FFM) and percentage FM (% FM) at 12 mo, and to evaluate obesity-related outcomes at 24 mo, compared with a no supplementation group. METHODS: This analysis is a secondary objective of a 3-arm randomized controlled trial in Delhi, India. Six-mo-old infants were allocated (1:1:1) to receive 1 daily packet of isocaloric high-protein supplementation (5.6 g), moderate-protein supplementation (2.5 g), or no supplementation. The isocaloric supplements provided 30% protein from milk, 30%-45% energy from fats, and 80%-100% recommended dietary allowance of key micronutrients. Comparisons were made between the no supplementation group and each supplementation group. RESULTS: Obesity prevalence was low at 12 mo (0.8% moderate-protein, 0.4% high-protein, 0.6% no supplementation; P = 0.65, no significant difference between groups) and at 24 mo (0.6% in supplemented groups, 0.2% no supplementation; P = 0.56, not significant). High-protein supplementation led to a modest but statistically significant increase in BMIz at 12 mo [adjusted mean difference: 0.12; 95% confidence interval (CI): 0.02, 0.22] compared with the no supplementation group, but not at 24 mo (-0.02; 95% CI: -0.12, 0.09). No significant differences were observed in FM, FFM, or %FM at 12 mo. CONCLUSIONS: High-protein supplementation from 6 to 12 mo did not increase fat accretion or obesity risk at 24 mo. Nutritional interventions in LMICs should prioritize both protein quality and overall dietary balance to simultaneously prevent undernutrition and excess weight gain. This study was registered at http://ctri.nic.in/Clinicaltrials/login.php as CTRI/2018/04/012932 for the main trial and CTRI/2019/03/018238 for the follow-up study.