Although the literature on the contribution of DHA and arachidonic acid (ARA) to fundamental metabolic functions in brain, immune and cardiovascular systems is extensive, there is a lack of consensus on the need for explicit recommendations on dietary intake for both DHA and ARA during the early years of life. This review takes a public health perspective with the objective of ensuring that recommendations protect the most vulnerable children worldwide. Most studies on the effects of DHA and ARA in early life have been undertaken in high-income countries and this is reflected in policy recommendations. Although breast milk is considered the gold standard and always contains DHA and ARA, there are proposals that infant formulas, especially follow-on formulas, do not need to be supplemented with these fatty acids. Complementary foods frequently have low concentrations of ARA and DHA and this is most significant in low-income countries where availability is also limited. Recent evidence shows that in developing countries, intakes of DHA and ARA during the age period 6–36 months are low and this relates to low national income. It is concluded that a continuum of DHA and ARA intake needs to be maintained during early life, a critical period of infant growth and development. For both infant and follow-on formulas, DHA and ARA should be mandatory at levels that are equivalent to breast milk. An optional recommendation may be limited to countries that can demonstrate evidence of adequate intakes of DHA and ARA during early life.

Normalization of the dimensions of cardiac structures to the size of the body, using so-called Z scores, is becoming increasingly common in the management of infants and children with congenital heart disease. Current published nomograms for the ascertainment of Z scores for cardiac structures in childhood are based largely on normal data obtained in formalin-fixed hearts. Since decisions concerning management are frequently based on the findings of cross-sectional echocardiograms, the dimensions of 15 cardiac structures were measured using cross-sectional echocardiography in 125 normal infants and children. Regression equations were derived relating cardiac dimensions to the size of the body. The expression of size with the highest correlation to cardiac dimensions was body surface area. Nomograms were then developed from which the Z score of a cardiac structure could be estimated from a knowledge of the body surface area and the echocardiographically derived measurement.