Introduction
This table provides a structured review of the main formulas available for infants and their clinical context according to current recommendations.
Standard formulas (Stage 1 milk)
Standard formulas, commonly referred to as “stage 1 milk”, are the first-line alternative when breastfeeding is not possible. They are used during the initial period before complementary feeding and provide intact cow’s milk protein with a composition adapted to the first year of life. The volume and frequency of feeds should be adjusted according to the infant’s age and weight. There is no proven benefit in replacing these formulas with special options in healthy infants without gastrointestinal symptoms.
Follow-on formulas (Stage 2 milk)
Follow-on formulas, or “stage 2 milk”, are commonly used after six months in the context of complementary feeding. Although widely promoted, they have not shown clinical superiority over standard formulas in healthy infants and are essentially a nutritional option rather than a therapeutic necessity.
Growing-up milks
So-called growing-up milks are usually intended for children between one and three years of age. They are not considered essential for all children, but may be included in specific strategies to optimise intake of iron, vitamin D and omega-3 fatty acids when the diet is poorly varied. In a balanced diet, their use is optional.
Formulas for cow’s milk protein allergy
Partially hydrolysed formulas were promoted for many years as a preventive measure against atopy; however, current recommendations do not support their use for this purpose. They may be considered in non-breastfed infants with mild functional gastrointestinal discomfort, but should not be prescribed with a prophylactic intention.
Extensively hydrolysed formulas, derived from cow’s milk, are first-line treatment for uncomplicated cow’s milk protein allergy. Amino acid formulas are reserved for severe cases, situations with enteropathy, faltering growth or lack of clinical response to extensively hydrolysed formulas.
Functional formulas
Functional formulas are frequently sought by parents in the presence of non-specific gastrointestinal symptoms. Anti-regurgitation formulas (AR) may be useful in infants with frequent and clinically significant regurgitation, especially when associated with discomfort or impaired weight gain, after warning signs have been excluded.
Anti-constipation formulas include modifications in fat and mineral composition that may soften stools, although the available evidence remains limited and routine use is not recommended.
Anti-colic formulas have not shown robust benefit compared with standard formulas and are not recommended as a first-line approach for infant colic.
Lactose-free formulas
Lactose-free formulas are mainly intended for galactosaemia and congenital lactase deficiency. In secondary lactose intolerance, such as after gastroenteritis, they may be used temporarily. It is important to emphasise that these formulas do not treat cow’s milk protein allergy.
Soy formulas
Soy protein-based formulas offer no nutritional advantage over cow’s milk formulas. They have a role in galactosaemia, congenital lactase deficiency and for ethical or religious reasons. They are not recommended as first-line treatment for cow’s milk protein allergy before six months of age or in preterm infants, due to the risk of cross-allergy and metabolic considerations.
Formulas for preterm and low-birth-weight infants
Formulas intended for preterm and low-birth-weight infants have increased energy and protein density and are used during hospitalisation and in the early post-discharge period. Whenever possible, fortified breast milk remains the preferred strategy, with these formulas reserved for situations in which breast milk is insufficient or unavailable.
Milk and dairy quantities
Milk quantities should be adjusted according to the infant’s age, weight and growth pattern. In the first trimester, requirements are typically around 150 ml/kg/day, decreasing progressively with complementary feeding. Between one and three years of age, daily intake of milk or dairy equivalents is usually around 300–400 ml/day, within the context of a balanced diet.
