The benefits of breastfeeding are well established, promoting not only optimal growth and development of the infant, but also reducing the risk of illness and death from common infectious diseases (1). Breastfeeding has also been shown to reduce the risk of otitis media and malocclusion, and recent studies further suggest that breastfeeding may have longer-term health benefits, such as reducing the risk of obesity and type 2 diabetes in children and adolescents, and increasing intelligence quotient (IQ) (2-5). Evidence also indicates that breastfeeding confers benefits to mothers, lowering their risk of breast and ovarian cancer, and type 2 diabetes (2), as well as increasing the time between pregnancies (1). For many outcomes, the positive effect of breastfeeding is greater the longer breastfeeding is continued (6-8).

Various mechanisms for the health effects of breastfeeding have been described, including those related to the composition of breast milk and behaviours associated with breastfeeding. Breast milk contains substances with antimicrobial or immunological properties including anti-inflammatory factors, hormones, digestive enzymes and growth modulators that protect against infections (8, 9). Breast milk also contains long-chain polyunsaturated fatty acids and other nutrients important for brain development; nutrients which may also affects the body’s response to insulin and subsequent fat deposition, thus providing one possible mechanistic link between breastfeeding and longer-term outcomes including obesity, diet-related NCDs and IQ (10). Differing levels of protein intake and taste preferences among breastfed children may also affect long-term outcomes. Breastfeeding facilitates important bacterial and hormonal interactions between mother and infant that help prevent inflammation of the Eustachian tubes in the middle ear (11), and the sucking and swallowing motions and movements of breastfed children may also reduce risk of bacterial colonisation of the tubes (8), as well as promote proper craniofacial development (12), reducing the risk of otitis media and malocclusion, respectively. The health benefits to breastfeeding mothers are thought to be linked to the hormonal effects of prolonged milk production (6).

WHO recommends that infants should be exclusively breastfed for the first six months of life to achieve optimal growth, development and health. Thereafter, to meet their evolving nutritional requirements, infants should receive nutritionally adequate and safe complementary foods, while continuing to breastfeed up to 2 years of age or beyond (13). While complementary foods should be introduced to infants beginning at 6 months of age, breastfeeding continues to make an important nutritional contribution beyond this point. Between 12 and 23 months of age, an average breast milk intake of about 500g/day still provides 35-40% of a child’s energy needs (14) and is a good source of essential fatty acids and vitamins which may be comparatively lower in most complementary foods (15).

Recent evidence indicates that globally the prevalence of continued breastfeeding at 12–15 months has decreased from 76% to 73%, with rates at 12 months reported to be highest in sub-Saharan Africa, South Asia and parts of Latin America (1). The decrease in prevalence appears to be driven largely by changes in breastfeeding practices among those with lower socioeconomic status (SES) both within and across countries; though mothers with lower SES still tend to breastfeed for longer than those with higher SES, continued breastfeeding rates overall appear to be decreasing in poorer populations while remaining stable in wealthier populations. This trend would suggest that as income increases, mothers may shorten duration of breastfeeding or otherwise negatively modify breastfeeding practices (16). Reasons for declining rates can be explained by a myriad of individual and societal factors, which include the attitudes of spouses/partners and others in the community towards breastfeeding, cultural beliefs, lack of a supportive environment in the workplace, poor technique and non-abidance to the International Code of Marketing of Breast-milk Substitutes (17).

Actions to counter declining breastfeeding rates through the support and promotion of breastfeeding include: implementation of the Baby-friendly Hospital Initiative, information dissemination and public education about the benefits of breastfeeding, incorporating breastfeeding into NCD prevention programmes, fostering positive societal attitudes towards breastfeeding, enforcing the Code which ensures responsible marketing of breast-milk substitutes and encouraging monitoring and evaluation of interventions and trends in breastfeeding (16). While interventions implemented individually may have some degree of success in increasing desirable breastfeeding practices, case studies suggest that simultaneous implementation of multiple interventions may have a stronger, synergistic effect on breastfeeding rates (1).

Fostering good nutrition practices during the critical period from birth to 2 years of age has been recognised as essential for optimal mental and motor development, growth and immunity. While additional research is needed to further clarify the effect of continued breastfeeding on certain health outcomes, available evidence strongly supports continued breastfeeding for health benefits to both mothers and children.

References

1. Victora CG, Bahl R, Barros AJ, França GV, Horton S, Krasevec J, Murch S, Sankar MJ, Walker N, Rollins NC, Group TL. Breastfeeding in the 21st century: epidemiology, mechanisms, and lifelong effect. The Lancet. 2016;387(10017):475-90.

2. Horta BL, Loret de Mola C, Victora CG. Long‐term consequences of breastfeeding on cholesterol, obesity, systolic blood pressure and type 2 diabetes: a systematic review and meta‐analysis. Acta Paediatrica. 2015;104(S467):30-7.

3. Horta BL, de Mola CL,Victora CG. Breastfeeding and intelligence: a systematic review and meta-analysis. Acta Paediatrica. 2015;104(S467):14–9.

4. Peres KG, Cascaes AM, Nascimento GG, Victora CG. Effect of breastfeeding on malocclusions: a systematic review and meta-analysis. Acta Paediatrica. 2015;104(S467):54–61.

5. Victora CG, Horta BL, de Mola CL, Quevedo L, Pinheiro RT, Gigante DP, et al. Association between breastfeeding and intelligence, educational attainment, and income at 30 years of age: a prospective birth cohort study from Brazil. The Lancet Global Health. 2015;3(4):e199-e205.

6. Chowdhury R, Sinha B, Sankar MJ, Taneja S, Bhandari N, Rollins N, et al. Breastfeeding and maternal health outcomes: a systematic review and meta-analysis. Acta Paediatrica. 2015; 104(S467):96–113.

7. Peres KG, Cascaes AM, Nascimento GG, Victora CG. Effect of breastfeeding on malocclusions: a systematic review and meta-analysis. Acta Paediatrica. 2015; 104(S467):54–61.

8. Bowatte G, Tham R, Allen KJ, Tan DJ, Lau M, Dai X, Lodge CJ. Breastfeeding and childhood acute otitis media: a systematic review and meta-analysis. Acta Paediatrica. 2015; 104(S467):85–95.

9. Horta BL, Victora CG. Short-term effects of breastfeeding–a systematic review on the benefits of breastfeeding on diarrhoea and pneumonia mortality. Geneva: World Health Organization; 2013. (http://www.who.int/maternal_child_adolescent/documents/breastfeeding_short_term_effects/en/)

10. Horta BL, Victora CG. Long-term effects of breastfeeding-a systematic review. Geneva: World Health Organization; 2013. (http://www.who.int/maternal_child_adolescent/documents/breastfeeding_long_term_effects/en/)

11. Abrahams SW, Labbok MH. Breastfeeding and otitis media: a review of recent evidence. Curr Allergy Asthma Rep. 2011;11(6):508-12.

12. Peres KG, Barros AJ, Peres MA, Victora CG. Effects of breastfeeding and sucking habits on malocclusion in a birth cohort study. Rev Saude Publica. 2007;41(3):343-50.

13. WHO/UNICEF. Global strategy on infant and young child feeding. Geneva: World Health Organization; 2003. (http://www.who.int/nutrition/publications/infantfeeding/9241562218/en/)

14. Dewey K, Brown K. Update on technical issues concerning complementary feeding of young children in developing countries and implications for intervention programs. Food and Nutrition Bulletin. 2003;24:5-28.

15. Guiding principles for complementary feeding of the breastfed child. Washington, DC: Pan American Health Organization; 2003 (http://www.who.int/maternal_child_adolescent/documents/a85622/en/).

16. Rollins NC, Bhandari N, Hajeebhoy N, Horton S, Lutter CK, Martines JC, et al. Why invest, and what it will take to improve breastfeeding practices? The Lancet. 2016;387(10017):491-504.

17. Odom EC, Li R, Scanlon KS, Perrine CG, Grummer-Strawn L. Reasons for earlier than desired cessation of breastfeeding. Pediatrics. 2013;131(3):e726-32.