The Importance of Nutrition during the First 1000 days – Protein in Infancy

Nutrition before and after birth (“first 1000 days”) is important for later health and wellbeing.  In this blog we address protein intake during infancy.

Protein is an essential macronutrient and important for all physical and mental functions. After water, protein is the most abundant substance in the body (if people are not overweight or obese).

In children without sufficient protein supply (often observed in developing countries) there is inadequate growth and development. In particular during early infancy, healthy growth patterns (according to the WHO growth standards) are observed only when the daily protein supply is sufficient and the protein quality is not strongly deviating from that of breast milk. The infant doubles its birth-weight during the first 3-4 months of life, therefore, protein requirements during early infancy, per unit of body weight, are much higher than that of older infants, children, and adults. As an example, young infant’s needs per unit of body weight are more than 2x higher than that of a weight lifter who takes protein supplements for muscle build up.

During later infancy however, protein requirements per unit of body weight are much lower. Fortunately in the case of infant feeding we have breast-milk as the “gold standard” which provides protein in its best quantity and quality during the whole breastfeeding period. WHO recommends exclusive breastfeeding until 6 months and continuation of breastfeeding until 2 years of age. 

Recently it became clear that the protein concentration in breast-milk decreases during the lactation period – i.e. high during the first weeks when growth is very fast and much lower during the later period of infancy when growth slows down.

Unfortunately, not all infants can be breastfed or are breastfed only for a short period of time. Today most of them receive infant formulas (0-6m) and follow-up formulas (6-36m) with much higher protein concentrations than in breast milk. Infants receiving high protein formulas tend to grow faster than breastfed infants. They have higher insulin- and IGF-levels in plasma, which might trigger their accelerated growth. Rapid weight gain during infancy is associated with higher risk of childhood- and adult obesity (GROW FAST- PAY LATER). This is an example on how early “metabolic programming” of the human body can go wrong.

Infants receiving low protein infant formula grow similar to breastfed infants. Therefore breastfed Infants or the ones receiving low protein formulas are at lower risk to become overweight or obese during childhood and in adult life.  The right nutrition after birth can influence the long-term activity of key genes in our body-“metabolic programming”- which is important to protect from obesity later in life.

WHO Multicentre Growth Reference Study Group. WHO Child Growth Standards: Length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age: Methods and development. Geneva: World Health Organization, 2006.

Lönnerdal B. Human milk proteins: Key components for the biological activity of human milk. In:Pickering et al., eds. Protecting Infants through Human Milk. Kluwer Academic/Plenum Publishers2004:11-25

Koletzko B. et al. Protein intake in the first year of life: a risk factor for later obesity? The E.U. childhood obesity project. Adv Exp Med Biol 2005;569:69-79.

Am J Clin Nutr. 1982 May;35(5 Suppl):1169-75.

Fomon SJ, Haschke F, Ziegler EE, Nelson SE