The study published in the British Journal of Nutrition compared the impact of low protein formula (close to that found in human breast milk) to higher protein formula.
Nutrients regulate brain development during the critical window of the first two years of life and nutrition during these important years may have an impact on later cognitive functioning.
The safety analysis is also of interest as part of an overall strategy to reduce the risk of obesity.
Protein supplementation has been shown in previous studies to have a beneficial impact on the infant’s development and later intelligence and educational achievement. However recent trends on protein recommendations during infancy and childhood have tended to be lower than in the past, in an effort to reduce obesity.
A joint report by the World Health Organisation (WHO) and the United Nation's (UN) Food and Agriculture Organisation (FAO) in 2007 showed a significant reduction in protein recommendation for infants and children but with a recommendation that future research examine the links between intakes and functions such as mental performance.
Long-term impacts
As part of the EU Childhood Obesity Project Group (CHOP) clinical trial, healthy weight infants from five European countries were randomised to be fed either a higher or lower protein formula in the first year of life.
The higher protein infant formula contained 2.9 g protein per 100 kcal and follow on formula 4.4 g protein per 100 ml, and lower protein infant formula contained 1.77 g protein per 100 kcal and 2.2 g per 100 ml for the follow on formula.
537 children were assessed at eight years old using a range of neuropsychological tests. Their growth was also monitored until six years old. Mothers assessed their children’s behaviour using the Child Behaviour Checklist. Confounding factors such as parents’ education level, smoking and infant delivery method were also considered.
There were no statistically significant differences between the low and high protein groups in any of the assessed areas such as visual and verbal memory, verbal comprehension and fluency, decision making, attention and behaviour.
Analysis of children who had been breastfed compared to formula fed at enrolment also showed similar behaviour and performance.
However, the authors suggested this may be because the study limited breast feeding to the first three months. Results of longer duration of breastfeeding may be more consistent with previous studies which showed a duration-dependent effect on brain development.
Source: British Journal of Nutrition
Published online ahead of print, http://dx.doi.org/10.1017/S0007114515000768
“Mental performance in 8-year-old children fed reduced protein content formula during the 1st year of life: safety analysis of a randomised clinical trial”
Authors: J. Escribano et al.