Low-Protein Infant Formula and Obesity Risk

Abstract

Infant formulas have been designed to mimic human milk for infants who cannot be breastfed. The overall goal is to establish similar functional outcomes to assure optimal growth, development, maturation of the immune system, and programming of the metabolic system. However, after decades of improving infant formula, growth patterns and body composition development are still different in formula-fed infants compared to breastfed infants, which could contribute to an increased risk of obesity among formula-fed infants. It has been hypothesized that the lower protein concentration of breast milk compared to infant formula influences infants’ growth and body composition. Thus, several trials in formula-fed infants with different protein intake levels have been performed to test this hypothesis. In this review, we discuss the current evidence on low-protein infant formula and obesity risk, including future perspectives and implications.

Nitrogen metabolism of the infant gut microbiota: a new focus on human milk prebiotics

“…Interestingly, according to enzymatic assay, only the presence of urea made B. infantis active in degrading urea, which indicates some form of metabolic switching and regulation according to the enzymatic assays (Figure 3A). Similar observations were made for other bacteria hosted by humans that have proven to be urease active and that specifically transcription was regulated by UreR in the presence of urea [42,93]. The fact that the presence of urea is required for B. infantis was furthermore observed in Streptococcus thermophilus, while also indicating that aspartate metabolism and glutamate metabolism might be linked to urease activity [79,94].…”

“…According to current knowledge, most PAs are however adsorbed in the upper intestine in support of growth processes of the human body [93]. In the infant GItract however, optimal adsorption might be developing in combination with a large supply through HM, causing polyamines to reach the colon.…”

“…Therefore, childhood obesity that sets on at infancy can be considered a major public health issue. Infant feeding may play a prophylactic role lowering the risk for obesity for later life [93].…”

“…It has been shown that a formula diet traditionally possesses up to 70% more protein than human milk [91]. Current formula products have per advice lowered protein levels and human milk is the golden standard for neonates [93,98]. Notably, infants that received formula early on in their lives are in a higher-risk group for allergies and disease onset [92][93][94][95][96].…”

“…Current formula products have per advice lowered protein levels and human milk is the golden standard for neonates [93,98]. Notably, infants that received formula early on in their lives are in a higher-risk group for allergies and disease onset [92][93][94][95][96]. However, recent standards and research into formula protein levels have indicated that protein levels closer to human milk are desirable for infant health and formulae following that concept have thus been developed [97][98][99][100].…”