Nutritional value of the hen egg for humans

Abstract

The egg is a highly digestible source of proteins and lipids, which contains a large range of vitamins and minerals needed by humans.The amino acid content, perfectly balanced for human needs, classifies eggs amongst the highest nutritional value of protein sources.Egg lipids provide large amounts of unsaturated fatty acids and phospholipids. The major egg components show limited variability;it essentially depends on egg white/yolk ratio, which is largely controlled by the hen's age. On the contrary, large differences can beobserved for egg content in fatty acids, vitamins, minerals and pigments. The influence of the hen's diet on egg composition for theseelements enables the enrichment of eggs for human health benefit. For example, nutritional studies have demonstrated in humans thepositive impact of consumption of unsaturated fatty acid enriched eggs; in addition, lutein and zeaxanthin are very efficientlyabsorbed by humans and highly available for the retina when provided by eggs. In addition, the negative image of the egg due to itshigh cholesterol content tends to be attenuated because the assumption of increased cardiovascular risk is not supported by themajority of epidemiological studies. One constrain to egg consumption is associated with allergenic proteins, and care should be takenespecially for young children.