ESSENTIAL FATS : HOW DO THEY AFFECT GROWTH AND DEVELOPMENT OF INFANTS AND YOUNG CHILDREN IN DEVELOPING COUNTRIES? A LITERATURE REVIEW

The omega-3 fatty acid alpha-linolenic acid (ALA) and the omega-6 fatty acid linoleic acid (LA) are essential fatty acids (EFAs) as they cannot be produced by the human body. The omega-6 fatty acid LA can be converted into longer chain metabolites, including arachidonic acid (AA) and the omega-3 fatty acid ALA can be converted into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Conversion rates are lower in infants (especially premature infants) than adults. The brain is composed of large amounts of both DHA and AA. During the third trimester of pregnancy and first year of life, the brain grows rapidly and an adequate supply of both of these fatty acids is thought to be essential for optimal development. A clinical deficiency of ALA or LA results in neurological abnormalities and poor growth. Overall, intakes of fat and omega-3 fatty acids appear to be low among many pregnant and lactating women, and non-breastfed infants.

Intake data on total fat in pregnant women were studied from six developing countries namely Bangladesh, Burkina Faso, Chile, China, India and Mexico. In all these countries, total fat intakes were within the daily recommended intake in pregnant and lactating women in studies in Chile, China, India and Mexico but not in Bangladesh, Burkina Faso and Sudan. In studies in India, Chile, Mexico, Sudan, Bangladesh, among pregnant or lactating women, mean intakes of ALA just met or were lower than the AI. In contrast, LA intakes exceeded the allowance in most countries except Bangladesh. The lowest DHA intakes were reported in India in the third trimester of pregnancy at only 11 mg.

Total fat intakes of total fat and individual fatty acids in infants and young children in many developing countries, especially in infants who are not breastfed, are lower than the minimum recommended of 35% at 6–24 months of age.

Data from three out of five studies from developing countries suggest that a higher EPA/DHA intake or ALA supplementation during pregnancy may result in small improvements in birthweight and length, and gestational duration. Limited data from developing and developed countries suggest that DHA concentration in breast milk or DHA supplementation during lactation might be linked to improved infant growth and psychomotor and cognitive development. Limited data from developing countries suggest that ALA or DHA supplementation is beneficial for infant's growth and development in these settings. These benefits are more pronounced in undernourished children and apparently healthy children from low socioeconomic status where indications are that intake of fatty acids at this age may be low.

Ensuring adequate intakes of fat, essential fatty acids and especially DHA through these life stages is crucial. Cost effective dietary sources of these fatty acids and exclusive breastfeeding until 6 months of age, and continued breastfeeding thereafter, in addition to appropriate complementary feeding are needed to ensure adequate essential fatty acid and DHA intakes in these populations.

(Source: Huffman SL, Harika RK, Eilander A, and Osendarp SJM. Maternal & Child Nutrition. 2011; 7(s3) 44–65)