Higher protein intake increases cardiac function parameters in healthy children: metabolic programming by infant nutrition-secondary analysis from a clinical trial

BACKGROUND: Protein intake may modulate cardiac structure and function in pathological conditions, but there is a lack of knowledge on potential effects in healthy infants. METHODS: Secondary analysis of an ongoing randomized clinical trial comparing two groups of infants receiving a higher (HP) or lower (LP) protein content formula in the first year of life, and compared with an observational group of breastfed (BF) infants. Growth and dietary intake were assessed periodically from birth to 2 y. Insulin-like growth factor 1 (IGF-1) axis parameters were analyzed at 6 mo in a blood sample. At 2 y, cardiac mass and function were assessed by echocardiography. RESULTS: HP infants (n = 50) showed a higher BMI z-score at 2 y compared with LP (n = 47) or BF (n = 44). Cardiac function parameters were increased in the HP group compared with the LP and were directly related to the protein intake during the first 6 mo of life. Moreover, there was an increase in free IGF-1 in the HP group at 6 mo. CONCLUSION: A moderate increase in protein supply during the first year of life is associated with higher cardiac function parameters at 2 y. IGF-1 axis modifications may, at least in part, underlie these effects.