National Nutrition Week: Feeding smart from the start

There is general consensus that “feeding smart from the start” implies exclusive breastfeeding for the first six months of an infant’s life. It is important to note the WHO recommendation on exclusive breastfeeding up to six months old for all, including HIV-infected mothers receiving antiretroviral therapy, and continued breastfeeding with complementary feeding up to one year for HIV-infected and up to two years and beyond for uninfected mothers. This recommendation is, however, not practiced by a large proportion of women in South Africa. Results of the 2003 South African Demographic and Health Survey showed that only 13.4% of infants younger than six months were exclusively breastfed. Advice about nutrition for infants is often provided by health professionals with expertise in nursing or medicine.
Nutritionists and dietitians should become more visible in this field, as the real experts who can advise about infant nutrition. National Nutrition Week is the ideal opportunity for the nutrition community to promote exclusive breastfeeding up to six months and to advise mothers and caregivers about the timing and types of complementary food to introduce.

Early research in Germany showed that gastrointestinal and renal function is sufficiently mature to metabolise nutrients from complementary foods by the age of four months. Gastrointestinal function matures according to the nature of foods ingested and adaptation of enzyme activity is followed by appropriate hormonal responses. The ability of the infant to eat solid foods depends on neurodevelopment. Most infants can sit with support and can eat food fed by a spoon by the age of six months. By the age of eight months they can chew and swallow soft foods. From nine to 12 months most infants can use their fingers or a spoon to pick up food and can use both hands to drink from a cup. Most foods prepared for the family can now be adapted for the infant by mashing or cutting into small, soft pieces. There is evidence that lumpy foods should be offered by around 10 months of age to prevent later feeding difficulties. Physiologically most infants are ready to accept solid foods by the age of six months.

By the age of six months the volume of breastmilk ingested by an infant becomes insufficient to meet the requirements for energy, protein, iron, zinc and vitamin A. It is important to introduce good sources of iron, zinc and vitamin A as first complementary foods. Iron deficiency was found among 27% of South African children 1-3 years old in the 2005 NFCS-Fortification Baseline. Commercial infant cereal products are a popular choice of South African mothers. These cereals are fortified with iron, zinc and vitamins, including vitamin A. A South African study showed that infants who received fortified cereal achieved significantly higher motor development scores, compared to the control group. The proportion of infants with anemia decreased from 45% to 17% in the fortified-porridge group, whereas it remained above 40% in the control group. The study showed that a low-cost fortified porridge can potentially have a significant effect in reducing anemia and improving iron status and motor development of infants in poor socio-economic settings. Yellow vegetables are often introduced early and are good sources of vitamin A, but do not contribute sufficient protein, iron or zinc. However, yellow vegetables and fruits make a valuable contribution to the mixed complementary diet. Pureed meat is an excellent source of highly bioavailable iron and zinc and has been shown to be acceptable as first complementary food at the age of five to seven months. Meat is also a source of arachidonic acid, a major long-chain poly-unsaturated fatty acid (LCPUFA) in the brain. In a study in the United Kingdom a positive association between meat intake averaged over 4-16 months of age and psychomotor development at 22 months was found.

Certain foods, such as eggs, seafood and nuts are more allergenic than others. Evidence suggests that introduction of more than four foods before the age of four months is associated with an increased risk of short-term as well as long-term atopic dermatitis. The most effective dietary measure to prevent allergies remains exclusive breastfeeding for 4-6 months. New foods should be introduced one at a time for 2-3 consecutive days to allow detection of potentially allergenic foods, such as fish and eggs. The American College of Allergy, Asthma and Immunology advised that the introduction of eggs should be delayed until 24 months and fish until three years in at-risk infants. This advice has been questioned by the ESPGHAN Committee, who believe that eggs and fish as good sources of LCPUFAs are important complementary foods. They found no convincing evidence that delayed introduction of eggs and fish reduces allergies. The introduction of small amounts of gluten while the infant is still breastfed may reduce the risk of celiac disease in infants. It was, however also found that late introduction of gluten, beyond the age of seven months, were associated with an increased risk of celiac disease. Prudent advice to mothers or caregivers of infants at risk of celiac disease is to introduce small amounts of gluten gradually while the infant still receives breastmilk and to avoid both early (before 4 months) and late (after 7 months) introduction of gluten.

Infants who received egg yolks enriched with docosahexaenoic acid (DHA) had higher red blood cell DHA levels and a greater increase in visual acuity resolution than matched infants from a control group. Although further research is necessary to establish whether long-term and broader effects on cognitive function are associated with increased intakes of LCPUFAs, it is advisable to include meat and oily fish as good sources of iron, zinc and LCPUFAs as complementary foods.

With the increasing incidence of childhood obesity and non-communicable diseases during early adulthood, it is important to consider the fat and salt content of complementary foods. A cohort study showed that infants who received complementary foods before 12 weeks had a higher body fat percentage at the age of seven years. Overconsumption of energy-dense complementary foods may cause excessive weight gain in infancy and increased risk of obesity in school-age children. Nutritionists advise mothers or caregivers who feed their infants with maize meal porridge on ways to increase the energy density of the porridge. Addition of oil or margarine to the porridge helps to increase energy density, but does not contribute iron or zinc, the critical nutrients for growth and cognitive development. Infancy appears to be a period of greater salt sensitivity than later in life. As a general guideline, additional salt should not be added to complementary foods. Further guidelines include avoiding frequent consumption of sweetened juice or cold drinks in bottles and discouraging the practice of sleeping with a bottle, both to prevent excessive weight gain and dental caries. Fruit juices and purees added to pureed vegetables may be encouraged, in order to increase the intake of vitamin C. Addition of vitamin C-rich juice to a complementary diet based on cereals helps to enhance the absorption of iron from cereals.

The age of six months to two years is a critical period of child growth and development and continued breastfeeding together with appropriate introduction of complementary foods has important short-term and long-term health benefits.

References:

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