Nutrition Across the Human Lifespan

The World Health Organization recommends exclusive breastfeeding for the first six months of life, since breast milk supplies a balance of macronutrients, immunoglobulins, and oligosaccharides that supports both growth and immune development; infant formula is an evidence-based alternative when breastfeeding is not possible or is combined with it. Around six months, an infant's iron stores accumulated during gestation begin to decline, which is why the introduction of iron-rich complementary foods at that stage is considered important for preventing iron-deficiency anemia. Guidance on introducing common allergenic foods has shifted in the last decade: trials such as the Learning Early about Peanut Allergy (LEAP) study found that early, rather than delayed, introduction of peanut-containing foods reduced the risk of peanut allergy in high-risk infants, prompting major pediatric bodies to revise their advice accordingly. Honey, added sugar, and added salt are avoided in the first year for reasons ranging from infant botulism risk to the shaping of long-term taste preferences.