Is Protein Supply in Infancy Linked to Childhood Obesity?

Speaker: M. Weber Presented at: 2015 Europediatrics 7th Biennial EPA/UNEPSA Congress


As a window of opportunity for prevention, nutrition in the first 1000 days of life offers the chance to achieve ideal growth, metabolic advantages, and optimal health in later life. Nutritional components of infants’ diets and their impact on anthropometrical development and metabolic mechanisms are therefore studied with huge interest. Protein, as a substantial macronutrient in human milk and in infant formula is a key driver in this process of early metabolic and anthropometrical programming.

The “Early Protein Hypothesis” is based on the observation that the increased protein intake by infant formula in contrast to human milk increases early weight gain, which is a known risk factor for later obesity. With the European Childhood Obesity Project “CHOP” we examined the impact of protein supply by formula on different growth parameters and metabolic changes throughout early to late childhood. In five European countries, about 1600 infants were recruited to be either randomized to formula with higher (HP, 2.05 g/dl) or lower (LP, 1.25 g/dl) protein content or to be followed as a breastfed reference group. The difference in protein intake achieved by the first year’s intervention was about 1 g/kg body weight which equates the differences observed between conventional formula feeding and breastfeeding in observational studies. 

Energy intake did not differ between groups Both formula groups showed a more rapid weight gain in the first year compared to breastfed infants. But the increased protein intake in the HP group was associated with a 0.23 SD higher BMI z-score (P<0.01) at 2 years compared to the LP group. The LP group closely resembled the growth pattern observed in breastfed infants. Since height was not different between the groups, BMI differences may be explained by an increased accumulation of body fat mass. In the long-term follow-up we observed a 0.51 kg/m² higher BMI (P<0.01), a higher FMI (0.16 kg/m², P=0.02), and a 2.4 fold (P=0.02) increased obesity risk comparing the HP to the LP group at the age of 6 years. The power of programming growth patterns up to early school age by modifying the infants’ diet in the first year of life offers huge possibilities for the improvement of later health. Breastfeeding with its beneficial effects should be promoted. Modification of protein quality and quantity in infant formula may help to fill the gap, if breastfeeding is not possible. Lowering the protein supply of infants and toddlers may be an effective strategy for obesity prevention.