The optimal duration of exclusive breastfeeding

Since 1979, the WHO recommendation for the duration of exclusive breastfeeding has been '4-6 months'. In 1994 and 1996, the World Health Assembly (WHA) and UNICEF recommended introduction of complementary foods at the age of about six months, thus recognizing that exclusive breastfeeding should be fostered for about the first six months. But the WHO did not change its previous recommendation, stating that further evidence was needed despite the fact that the world's experts have argued that evidence supporting the change in the recommendation was sufficient. IBFAN has always maintained that the delay in changing the recommendation resulted mainly in large profits gained by infant food manufacturers from sales of complementary foods for two additional months of complementary feeding.

During the 53rd WHA in the year 2000, the Brazilian delegation proposed a resolution in favour of exclusive breastfeeding for six months. The draft resolution did not pass and the WHO Secretariat tried to postpone any further resolution on infant feeding to 2002. But the members of the WHO Executive Board in January 2001 clearly stated the need for the resolution. Therefore the Board decided to keep the recommended duration of exclusive breastfeeding in brackets ('4-6 months' vs 'about 6 months') until an expert committee decided on this issue and also decided to forward the resolution to be discussed at the 54th WHA in May 2001.

In March, the report issued by the Expert Committee which was finally convened by the WHO Secretariat put an end to the long debate by endorsing exclusive breastfeeding for 6 months. Despite pressure from the baby food industry and some last-minute uncertainty, resolution WHA54.2 was eventually passed on 18 May 2001.

The resolution urges Member States to "... support exclusive breastfeeding for six months as a global public health recommendation taking into account the findings of the WHO Expert Technical Consultation on optimal duration of exclusive breastfeeding and to provide safe and appropriate complementary foods, with continued breastfeeding for up to two years or beyond ....".

The Expert Committee had identified, reviewed and evaluated more than 3,000 references. The studies comparing exclusive or predominant breastfeeding for about four months with the same pattern of feeding for about six months did not show an adverse effect of the latter on growth and major morbidity. The review, however, could not rule out an increased risk of growth faltering in some infants who are exclusively breastfed for six months, particularly in populations with severe maternal malnutrition and a high prevalence of intrauterine growth retardation. There might also be a risk of poorer iron status in infants exclusively breastfed for six months in populations in which maternal iron status and infant stores of iron are not optimal. On the other hand, the review confirmed that exclusive breastfeeding for six months protects against gastrointestinal infection, even in settings where hygienically prepared complementary foods are used, and confers an advantage in prolonging the duration of lactational amenorrhoea in mothers who breastfeed frequently (10-14 feeds a day).

The recommendation to exclusively breastfeed for six months applies to populations. It is clear that some mothers will be unable to, or choose not to, follow this recommendation; they should be supported to optimize their infants’ nutrition. Particular attention should be paid to the nutritional status of pregnant and lactating mothers, the micronutrient status of infants living in areas with high prevalence of iron, zinc, and vitamin A deficiencies, the routine care of individual infants, including assessment of growth and of clinical signs of micronutrient deficiencies.

Refs.

WHO. Expert consultation on the optimal duration of exclusive breastfeeding. Conclusions and recommendations. Document A54/INF.DOC./4, Geneva, 28-30 March 2001.

WHO. Global strategy for infant and young child feeding. Document A54/7, Geneva, 9 April 2001.

Key abstract

Dewey KG. Nutrition, growth, and complementary feeding of the breastfed infant. Pediatr Clin North Am 2001;48:87-104

The following conclusions about infant feeding are well substantiated by the evidence available to date, although additional research is needed on many issues.

Breastmilk alone can meet nutrient needs during the first 6 months, with the possible exception of vitamin D in certain populations, and iron in infants of relatively low birth weight.

Complementary foods offered before 6 months of age tend to displace breastmilk and do not confer any growth advantage over exclusive breastfeeding.

Breastmilk continues to provide substantial amounts of key nutrients well beyond the first year of life, especially protein, fat, and most vitamins.

Breastfed infants tend to gain less weight and usually are leaner than are formula-fed infants in the second half of infancy. This difference does not seem to be the result of nutritional deficits but rather infant self-regulation of energy intake. New growth charts based on infants breastfed throughout the first year of life are being developed by WHO.

The nutrients most likely to be limiting in the diets of breastfed infants are minerals, such as iron, zinc, and calcium. Using the following guidelines can help to ensure that the nutrient needs after 6 months of life of the breastfed child are met:

1. Continue to breastfeed as often as the infant desires.

2. Aim for a variety of complementary foods, with fruits, vegetables, and animal products (e.g., meat, fish, poultry, or eggs) offered daily.

3. Iron-fortified cereals and meats can provide adequate iron.

4. Calcium can be obtained from cheese, yogurt, and other dairy products (although fresh cow's milk is not recommen-ded before 12 months).

5. Avoid giving too much juice.

6. Be alert to any signs that the child's appetite, growth, or develop-ment is impaired.

7. When in doubt, a balanced vitamin-mineral supplement is advisable.

8. Make mealtimes enjoyable.