Fats are the main source of energy for satisfactory growth and physical activity during early infancy. This energy requirement is not easily met where diets are low in fat (less than 15 percent of total calories), which partly explains the high prevalence of malnutrition in such areas.
Fats should also be considered in terms of their structural function during the first two years of life. They provide the fatty acids and cholesterol needed to form cell membranes in all the organs. Moreover, important organs such as the retina and the central nervous system are mainly composed of fats.
Most of the fats needed to form these tissues are essential fatty acids (EFAs) which cannot be synthesized by the organism and have to be acquired through nutrition. Mother's milk has a special fat composition that makes it unique for good child nutrition. It contains factors that facilitate the digestion of fats, while its chemical composition makes it more digestible and includes a balanced supply of n-6 and n-3 fatty acids.
Recent documented research on n-3 a -linolenic acid and docosahexaenoic acid (DHA) has focused on effects on growth and brain development. In 1993, the Joint FAO/WHO Expert Consultation on Fats and Oils in Human Nutrition stressed that infants should be breast-fed if possible and that breast-milk substitutes (infant formula) should mimic breast milk in faty acid content.
There is a relationship between consumption of fats and income level in developing countries. Fat consumption is insufficient in low-income groups, and this lower consumption of fats and oils has an adverse effect on the nutritional energy status of children and adults in these groups.