INFANT AND YOUNG CHILD FEEDING-MODEL CHAPTER FOR TEXTBOOKS the young child's energy and nutrient needs.How- 12.WHO/UNICEF/USAID.Indicators for assessing ever,complementary feeding is often fraught with infant and young child feeding practices.Geneva, problems,with foods being too dilute,not fed often World Health Organization,2008. enough or in too small amounts,or replacing breast milk while being of an inferior quality.Both food and 13.PAHO/WHO.Guiding principles for complemen- tary feeding of the breastfed child.Washington feeding practices influence the quality of complemen- DC,Pan American Health Organization/World tary feeding,and mothers and families need support to practise good complementary feeding(13). Health Organization,2002 14.WHO Global Data Bank on Infant and Young References Child Feeding,2009. 1.World Health Organization.The global burden 15.UNICEF.Progress for children:a world fit for chil- of disease:2004 update.Geneva,World Health dren.Statistical Review Number 6.New York, Organization,2008. UNICEF,2007. 2.Black RE et al.Maternal and child undernutri- 16.Leon-Cava N et al.Quantifying the benefits of breast- tion:global and regional exposures and health feeding:a summary of the evidence.Washington consequences.Lancet,2008,371:243-60. DC,Pan American Health Organization,2002. 3.Martorell R,Kettel Khan L,Schroeder DG. 17.Fewtrell MS.The long-termbenefits ofhavingbeen Reversibility of stunting:epidemiological find- breastfed.Current Paediatrics,2004,14:97-103. ings in children from developing countries. European Journal of Clinical Nutrition,1994,58 18.WHO.Evidence on the long-term effects of breast- (Suppl.1):S45-S57. feeding:systematic reviews and meta-analyses. Geneva,World Health Organization,2007. 4.Pollitt E et al.Nutrition in early life and the ful- 19.WHO Collaborative Study Team on the Role of filment of intellectual potential.The Journal of Breastfeeding on the Prevention of Infant Mor- Nutrition,1995,125:1111S-1118S tality.Effect of breastfeeding on infant and child- 5.Grantham-McGregor SM,Cumper G.Jamai- hood mortality due to infectious diseases in less can studies in nutrition and child development, developed countries:a pooled analysis.Lancet, and their implications for national development. 2000,355:451-455 The Proceedings of the Nutrition Society,1992,51: 20.Bahl R et al.Infant feeding patterns and risks of 71-79. death and hospitalization in the first half of infan- 6.Haas JD et al.Early nutrition and later physical cy:multicentre cohort study.Bulletin of the World work capacity.Nutrition reviews,1996,54(2,Pt2): Health Organization,2005,83:418-426. S41-48. 21.De Zoysa I,Rea M,Martines J.Why promote 7.Martin RM et al.Parents'growth in childhood breast feeding in diarrhoeal disease control pro- and the birth weight of their offspring.Epidemiol- grammes?Health Policy and Planning,1991, 0gy2004,15:308-316. 6:371-379. 8.World Bank.Repositioning nutrition as central 22.Bachrach VR,Schwarz E,Bachrach LR.Breast- to development:a strategy for large scale action. feeding and the risk of hospitalization for respira- Washington DC,The World Bank,2006. tory diseases in infancy:a meta-analysis.Archives 9.Jones G et al.How many child deaths can we pre- of Pediatrics and Adolescent Medicine,2003, 157:237-243. vent this year?Lancet,2003,362:65-71. 10.WHO/UNICEF.Global strategy for infant and 23.Kramer MS et al.Promotion of Breastfeeding young child feeding.Geneva,World Health Organ- Intervention Trial(PROBIT):a randomized trial in the Republic of Belarus.Journal of the American ization,2003 Medical Association,2001,285:413-420. 11.Kramer MS,Kakuma R.The optimal duration of exclusive breastfeeding:a systematic review.Gene- 24.Howie PW et al.Protective effect of breastfeeding va,World Health Organization,2001 (WHO/ against infection.British Medical Journal,1990, NHD/01.08;WHO/FCH/01.23). 300:11-16
6 Infant and Young Child Feeding – Model Chapter for textbooks the young child’s energy and nutrient needs. However, complementary feeding is often fraught with problems, with foods being too dilute, not fed often enough or in too small amounts, or replacing breast milk while being of an inferior quality. Both food and feeding practices influence the quality of complementary feeding, and mothers and families need support to practise good complementary feeding (13). References 1. World Health Organization. The global burden of disease: 2004 update. Geneva, World Health Organization, 2008. 2. Black RE et al. Maternal and child undernutrition: global and regional exposures and health consequences. Lancet, 2008, 371:243–60. 3. Martorell R, Kettel Khan L, Schroeder DG. Reversibility of stunting: epidemiological findings in children from developing countries. European Journal of Clinical Nutrition, 1994, 58 (Suppl.1):S45–S57. 4. Pollitt E et al. Nutrition in early life and the fulfilment of intellectual potential. The Journal of Nutrition, 1995, 125:1111S–1118S. 5. Grantham-McGregor SM, Cumper G. Jamaican studies in nutrition and child development, and their implications for national development. The Proceedings of the Nutrition Society, 1992, 51: 71–79. 6. Haas JD et al. Early nutrition and later physical work capacity. Nutrition reviews, 1996, 54(2,Pt2): S41–48. 7. Martin RM et al. Parents’ growth in childhood and the birth weight of their offspring. Epidemiology, 2004, 15:308–316. 8. World Bank. Repositioning nutrition as central to development: a strategy for large scale action. Washington DC, The World Bank, 2006. 9. Jones G et al. How many child deaths can we prevent this year? Lancet, 2003, 362:65–71. 10. WHO/UNICEF. Global strategy for infant and young child feeding. Geneva, World Health Organization, 2003. 11. Kramer MS, Kakuma R. The optimal duration of exclusive breastfeeding: a systematic review. Geneva, World Health Organization, 2001 (WHO/ NHD/01.08; WHO/FCH/01.23). 12. WHO/UNICEF/USAID. Indicators for assessing infant and young child feeding practices. Geneva, World Health Organization, 2008. 13. PAHO/WHO. Guiding principles for complementary feeding of the breastfed child. Washington DC, Pan American Health Organization/World Health Organization, 2002. 14. WHO Global Data Bank on Infant and Young Child Feeding, 2009. 15. UNICEF. Progress for children: a world fit for children. Statistical Review Number 6. New York, UNICEF, 2007. 16. Leon-Cava N et al. Quantifying the benefits of breastfeeding: a summary of the evidence. Washington DC, Pan American Health Organization, 2002. 17. Fewtrell MS. The long-term benefits of having been breastfed. Current Paediatrics, 2004, 14:97–103. 18. WHO. Evidence on the long-term effects of breastfeeding: systematic reviews and meta-analyses. Geneva, World Health Organization, 2007. 19. WHO Collaborative Study Team on the Role of Breastfeeding on the Prevention of Infant Mortality. Effect of breastfeeding on infant and childhood mortality due to infectious diseases in less developed countries: a pooled analysis. Lancet, 2000, 355:451–455. 20. Bahl R et al. Infant feeding patterns and risks of death and hospitalization in the first half of infancy: multicentre cohort study. Bulletin of the World Health Organization, 2005, 83:418–426. 21. De Zoysa I, Rea M, Martines J. Why promote breast feeding in diarrhoeal disease control programmes? Health Policy and Planning, 1991, 6:371–379. 22. Bachrach VR, Schwarz E, Bachrach LR. Breastfeeding and the risk of hospitalization for respiratory diseases in infancy: a meta-analysis. Archives of Pediatrics and Adolescent Medicine, 2003, 157:237–243. 23. Kramer MS et al. Promotion of Breastfeeding Intervention Trial (PROBIT): a randomized trial in the Republic of Belarus. Journal of the American Medical Association, 2001, 285:413–420. 24. Howie PW et al. Protective effect of breastfeeding against infection. British Medical Journal, 1990, 300:11–16
1.THE IMPORTANCE OF INFANT AND YOUNG CHILD FEEDING AND RECOMMENDED PRACTICES 25.Duncan B et al.Exclusive breast feeding for at least 37.Martin RM,Gunnell D,Davey Smith G.Breast- 4 months protects against otitis media.Pediatrics, feeding in infancy and blood pressure in later 1993,91:867-872 life:systemic review and meta-analysis.American 26.Silfverdal S,Bodin L,Olcen P.Protective effect Journal of Epidemiology,2005,161:15-26. of breastfeeding:An ecological study of Haemo- 38.Owen CG et al.Infant feeding and blood cho- philus influenzae meningitis and breastfeeding lesterol:a study in adolescents and a systematic in a Swedish population.International Journal of review.Pediatrics,2002,110:597-608. Epidemiology,1999,28:152-156. 39.Martin RM et al.Breastfeeding and atherosclero- 27.Marild S et al.Protective effect of breastfeeding sis:intima media thickness and plaques at 65-year against urinary tract infection.Acta Paediatrica, follow-up of the Boyd Orr Cohort.Arteriosclerosis 2004,93:164-168. Thrombosis Vascular Biology,2005,25:1482-1488. 28.Gdalevich M,Mimouni D,Mimouni M.Breast- 40.Anderson JW,Johnstone BM,Remley DT.Breast- feeding and the risk of bronchial asthma in child- feeding and cognitive development:a meta-anal- hood:a systematic review with meta-analysis of ysis.American Journal of Clinical Nutrition,1999, prospective studies.Journal of Pediatrics,2001, 70:525-535. 139:261-266. 41.Daniels MC,Adair LS.Breast-feeding influences 29.Oddy WH et al.The relation of breastfeeding and cognitive development in Filipino children.The Body Mass Index to asthma and atopy in children: Journal of Nutrition,2005,135:2589-2595. a prospective cohort study to age 6 years.Ameri- 42.Mortensen EL et al.The association between can Journal of Public Health,2004,94:1531-1537. duration of breastfeeding and adult intelligence. 30.Sadauskaite-Kuehne V et al.Longer breastfeed- Journal of the American Medical Association,2002, ing is an independent predictive factor against 287:2365-2371 development of type I diabetes in childhood. 43.Chua S et al.Influence of breast feeding and nip- Diabetes/Metabolism Research and Reviews,2004, 20:150-157. ple stimulation on post-partum uterine activity. British Journal of Obstetrics &Gynaecology,1994, 31.Akobeng AK et al.Effect of breastfeeding on risk 101:804-805. of coeliac disease:a systematic review and meta- 44.Collaborative Group on Hormonal Factors in analysis of observational studies.Archives of Dis- Breast Cancer.Breast cancer and breastfeed- eases in Childhood,2006,91:39-43. ing:collaborative reanalysis of individual data 32.Klement E et al.Breastfeeding and risk of inflam- from 47 epidemiological studies in 30 countries, matory bowel disease:a systematic review with including 50 302 women with breast cancer and meta-analysis.American Journal of Clinical Nutri- 96 973 women without the disease.Lancet,2002, ti0n,2004,80:1342-1352. 360:187-195. 33.Kwan ML et al.Breastfeeding and the risk of child- 45.Robenblatt K,Thomas D.Lactation and the risk of hood leukaemia:a meta-analysis.Public Health epithelial ovarian cancer.International Journal of Reports,2004,119:521-535. Epidemiology,1993,22:192-197. 34.Harder T et al.Duration of breastfeeding and risk 46.Feachem R,Koblinsky M.Interventions for the of overweight:a meta-analysis.American Journal control of diarrhoeal disease among young chil- of Epidemiology,2005,162:397-403. dren:promotion of breastfeeding.Bulletin of the 35.Burke V et al.Breastfeeding and overweight:lon- World Health Organization,1984,62:271-291. gitudinal analysis in an Australian birth cohort. 47.Victora C et al.Evidence for protection by breast- Journal of Pediatrics,2005,147:56-61. feeding against infant deaths from infectious dis- 36.Grummer-Strawn LM,Mei Z.Does breastfeed- eases in Brazil.Lancet,1987,330:319-322 ing protect against pediatric overweight?Analysis 48.Arifeen S et al.Exclusive breastfeeding reduces of longitudinal data from the Centers for Disease acute respiratory infection and diarrhoea deaths Control and Prevention Pediatric Nutrition Sur- among infants in Dhaka slums.Pediatrics,2001, veillance System.Pediatrics,2004,113:e81-86. 108:1-8
7 25. Duncan B et al. Exclusive breast feeding for at least 4 months protects against otitis media. Pediatrics, 1993, 91:867–872. 26. Silfverdal S, Bodin L, Olcén P. Protective effect of breastfeeding: An ecological study of Haemophilus influenzae meningitis and breastfeeding in a Swedish population. International Journal of Epidemiology, 1999, 28:152–156. 27. Marild S et al. Protective effect of breastfeeding against urinary tract infection. Acta Paediatrica, 2004, 93:164–168. 28. Gdalevich M, Mimouni D, Mimouni M. Breastfeeding and the risk of bronchial asthma in childhood: a systematic review with meta-analysis of prospective studies. Journal of Pediatrics, 2001, 139:261–266. 29. Oddy WH et al. The relation of breastfeeding and Body Mass Index to asthma and atopy in children: a prospective cohort study to age 6 years. American Journal of Public Health, 2004, 94:1531–1537. 30. Sadauskaite-Kuehne V et al. Longer breastfeeding is an independent predictive factor against development of type 1 diabetes in childhood. Diabetes/Metabolism Research and Reviews, 2004, 20:150–157. 31. Akobeng AK et al. Effect of breastfeeding on risk of coeliac disease: a systematic review and metaanalysis of observational studies. Archives of Diseases in Childhood, 2006, 91:39–43. 32. Klement E et al. Breastfeeding and risk of inflammatory bowel disease: a systematic review with meta-analysis. American Journal of Clinical Nutrition, 2004, 80:1342–1352. 33. Kwan ML et al. Breastfeeding and the risk of childhood leukaemia: a meta-analysis. Public Health Reports, 2004, 119:521–535. 34. Harder T et al. Duration of breastfeeding and risk of overweight: a meta-analysis. American Journal of Epidemiology, 2005, 162:397–403. 35. Burke V et al. Breastfeeding and overweight: longitudinal analysis in an Australian birth cohort. Journal of Pediatrics, 2005, 147:56–61. 36. Grummer-Strawn LM, Mei Z. Does breastfeeding protect against pediatric overweight? Analysis of longitudinal data from the Centers for Disease Control and Prevention Pediatric Nutrition Surveillance System. Pediatrics, 2004, 113:e81–86. 37. Martin RM, Gunnell D, Davey Smith G. Breastfeeding in infancy and blood pressure in later life: systemic review and meta-analysis. American Journal of Epidemiology, 2005, 161:15–26. 38. Owen CG et al. Infant feeding and blood cholesterol: a study in adolescents and a systematic review. Pediatrics, 2002, 110:597–608. 39. Martin RM et al. Breastfeeding and atherosclerosis: intima media thickness and plaques at 65-year follow-up of the Boyd Orr Cohort. Arteriosclerosis Thrombosis Vascular Biology, 2005, 25:1482–1488. 40. Anderson JW, Johnstone BM, Remley DT. Breastfeeding and cognitive development: a meta-analysis. American Journal of Clinical Nutrition, 1999, 70:525–535. 41. Daniels MC, Adair LS. Breast-feeding influences cognitive development in Filipino children. The Journal of Nutrition, 2005, 135:2589–2595. 42. Mortensen EL et al. The association between duration of breastfeeding and adult intelligence. Journal of the American Medical Association, 2002, 287:2365–2371. 43. Chua S et al. Influence of breast feeding and nipple stimulation on post-partum uterine activity. British Journal of Obstetrics & Gynaecology, 1994, 101:804–805. 44. Collaborative Group on Hormonal Factors in Breast Cancer. Breast cancer and breastfeeding: collaborative reanalysis of individual data from 47 epidemiological studies in 30 countries, including 50 302 women with breast cancer and 96 973 women without the disease. Lancet, 2002, 360:187–195. 45. Robenblatt K, Thomas D. Lactation and the risk of epithelial ovarian cancer. International Journal of Epidemiology, 1993, 22:192–197. 46. Feachem R, Koblinsky M. Interventions for the control of diarrhoeal disease among young children: promotion of breastfeeding. Bulletin of the World Health Organization, 1984, 62:271–291. 47. Victora C et al. Evidence for protection by breastfeeding against infant deaths from infectious diseases in Brazil. Lancet, 1987, 330:319–322. 48. Arifeen S et al. Exclusive breastfeeding reduces acute respiratory infection and diarrhoea deaths among infants in Dhaka slums. Pediatrics, 2001, 108:1–8. 1. The importance of infant and young child feeding and recommended practices
8 INFANT AND YOUNG CHILD FEEDING-MODEL CHAPTER FOR TEXTBOOKS 49.Kramer M et al.Infant growth and health out- 55.The World Health Organization Multinational comes associated with 3 compared with 6 months Study of Breast-feeding and Lactational Amenor- of exclusive breastfeeding.American Journal of rhea.III.Pregnancy during breast-feeding.World Clinical Nutrition,2003,78:291-295. Health Organization Task Force on Methods for 50.Chantry C,Howard C,Auinger P.Full breastfeed- the Natural Regulation of Fertility.Fertility and sterility,1999,72:431-440. ing duration and associated decrease in respirato- ry tract infection in US children.Pediatrics,2006, 56.Dewey KG et al.Effects of exclusive breastfeeding 117:425-432. for 4 versus 6 months on maternal nutritional sta- 51.Butte N,Lopez-Alarcon MG,Garza C.Nutrient tus and infant motor development:results of two adequacy of exclusive breastfeeding for the term randomized trials in Honduras.The Journal of utrition,2001,131:262-267. infant during the first six months of life.Geneva, World Health Organization,2002. 57.Dewey K and Brown K.Update on technical issues concerning complementary feeding of young chil- 52.LINKAGES.Exclusive breastfeeding:The only water source young infants need.FAQ Sheet 5 Frequently dren in developing countries and implications for Asked Questions.Washington DC,Academy for intervention programs.Food and Nutrition Bulle- Educational Development,2002. tim,2003,24:5-28 53.Sachdev H et al.Water supplementation in exclu- 58.Dewey KG,Adu-Afarwuah S.Systematic review sively breastfed infants during summer in the of the efficacy and effectiveness of complemen- tropics.Lancet,1991,337:929-933. tary feeding interventions in developing countries. Maternal and Child Nutrition,2008,4(s1):24-85. 54.Brown K et al.Infant feeding practices and their relationship with diarrhoeal and other diseases in Huascar(Lima)Peru.Pediatrics,1989,83:31-40
8 Infant and Young Child Feeding – Model Chapter for textbooks 49. Kramer M et al. Infant growth and health outcomes associated with 3 compared with 6 months of exclusive breastfeeding. American Journal of Clinical Nutrition, 2003, 78:291–295. 50. Chantry C, Howard C, Auinger P. Full breastfeeding duration and associated decrease in respiratory tract infection in US children. Pediatrics, 2006, 117:425–432. 51. Butte N, Lopez-Alarcon MG, Garza C. Nutrient adequacy of exclusive breastfeeding for the term infant during the first six months of life. Geneva, World Health Organization, 2002. 52. LINKAGES. Exclusive breastfeeding: The only water source young infants need. FAQ Sheet 5 Frequently Asked Questions. Washington DC, Academy for Educational Development, 2002. 53. Sachdev H et al. Water supplementation in exclusively breastfed infants during summer in the tropics. Lancet, 1991, 337:929–933. 54. Brown K et al. Infant feeding practices and their relationship with diarrhoeal and other diseases in Huascar (Lima) Peru. Pediatrics, 1989, 83:31–40. 55. The World Health Organization Multinational Study of Breast-feeding and Lactational Amenorrhea. III. Pregnancy during breast-feeding. World Health Organization Task Force on Methods for the Natural Regulation of Fertility. Fertility and sterility, 1999, 72:431–440. 56. Dewey KG et al. Effects of exclusive breastfeeding for 4 versus 6 months on maternal nutritional status and infant motor development: results of two randomized trials in Honduras. The Journal of Nutrition, 2001, 131:262–267. 57. Dewey K and 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. 58. Dewey KG, Adu-Afarwuah S. Systematic review of the efficacy and effectiveness of complementary feeding interventions in developing countries. Maternal and Child Nutrition, 2008, 4(s1):24–85
The physiological basis of breastfeeding Z NOISS3S 2.1 Breast-milk composition a baby.The concentration of protein in breast milk Breast milk contains all the nutrients that an infant (0.9 g per 100 ml)is lower than in animal milks.The needs in the first 6 months of life,including fat,car- much higher protein in animal milks can overload bohydrates,proteins,vitamins,minerals and water the infant's immature kidneys with waste nitrogen (1,2,3,4).It is easily digested and efficiently used. products.Breast milk contains less of the protein Breast milk also contains bioactive factors that aug- casein,and this casein in breast milk has a different ment the infant's immature immune system,provid- molecular structure.It forms much softer,more eas- ing protection against infection,and other factors ily-digested curds than that in other milks.Among that help digestion and absorption of nutrients. the whey,or soluble proteins,human milk contains more alpha-lactalbumin;cow milk contains beta- Fats lactoglobulin,which is absent from human milk and to which infants can become intolerant (4). Breast milk contains about 3.5 g of fat per 100 ml of milk,which provides about one half of the energy Vitamins and minerals content of the milk.The fat is secreted in small drop- lets,and the amount increases as the feed progresses. Breast milk normally contains sufficient vitamins for As a result,the hindmilk secreted towards the end of an infant,unless the mother herself is deficient (5). a feed is rich in fat and looks creamy white,while the The exception is vitamin D.The infant needs expo- foremilk at the beginning of a feed contains less fat and sure to sunlight to generate endogenous vitamin D- looks somewhat bluish-grey in colour.Breast-milk or,if this is not possible,a supplement.The minerals fat contains long chain polyunsaturated fatty acids iron and zinc are present in relatively low concentra- (docosahexaenoic acid or DHA,and arachidonic acid tion,but their bioavailability and absorption is high or ARA)that are not available in other milks.These Provided that maternal iron status is adequate,term fatty acids are important for the neurological devel- infants are born with a store of iron to supply their opment of a child.DHA and ARA are added to some needs;only infants born with low birth weight may varieties of infant formula,but this does not confer need supplements before 6 months.Delaying clamp- any advantage over breast milk,and may not be as ing of the cord until pulsations have stopped(approxi- effective as those in breast milk. mately 3 minutes)has been shown to improve infants' iron status during the first 6 months of life (6,7). Carbohydrates Anti-infective factors The main carbohydrate is the special milk sugar lac- tose,a disaccharide.Breast milk contains about 7g Breast milk contains many factors that help to protect lactose per 100 ml,which is more than in most other an infant against infection(8)including: milks,and is another important source of energy immunoglobulin,principally secretory immuno- Another kind of carbohydrate present in breast milk globulin A(slgA),which coats the intestinal mucosa is oligosaccharides,or sugar chains,which provide and prevents bacteria from entering the cells; important protection against infection(4). white blood cells which can kill micro-organisms; Protein whey proteins (lysozyme and lactoferrin)which Breast milk protein differs in both quantity and qual- can kill bacteria,viruses and fungi; ity from animal milks,and it contains a balance of oligosacccharides which prevent bacteria from amino acids which makes it much more suitable for attaching to mucosal surfaces
The physiological basis of breastfeeding 2.1 Breast-milk composition Breast milk contains all the nutrients that an infant needs in the first 6 months of life, including fat, carbohydrates, proteins, vitamins, minerals and water (1,2,3,4). It is easily digested and efficiently used. Breast milk also contains bioactive factors that augment the infant’s immature immune system, providing protection against infection, and other factors that help digestion and absorption of nutrients. Fats Breast milk contains about 3.5 g of fat per 100 ml of milk, which provides about one half of the energy content of the milk. The fat is secreted in small droplets, and the amount increases as the feed progresses. As a result, the hindmilk secreted towards the end of a feed is rich in fat and looks creamy white, while the foremilk at the beginning of a feed contains less fat and looks somewhat bluish-grey in colour. Breast-milk fat contains long chain polyunsaturated fatty acids (docosahexaenoic acid or DHA, and arachidonic acid or ARA) that are not available in other milks. These fatty acids are important for the neurological development of a child. DHA and ARA are added to some varieties of infant formula, but this does not confer any advantage over breast milk, and may not be as effective as those in breast milk. Carbohydrates The main carbohydrate is the special milk sugar lactose, a disaccharide. Breast milk contains about 7 g lactose per 100 ml, which is more than in most other milks, and is another important source of energy. Another kind of carbohydrate present in breast milk is oligosaccharides, or sugar chains, which provide important protection against infection (4). Protein Breast milk protein differs in both quantity and quality from animal milks, and it contains a balance of amino acids which makes it much more suitable for a baby. The concentration of protein in breast milk (0.9 g per 100 ml) is lower than in animal milks. The much higher protein in animal milks can overload the infant’s immature kidneys with waste nitrogen products. Breast milk contains less of the protein casein, and this casein in breast milk has a different molecular structure. It forms much softer, more easily-digested curds than that in other milks. Among the whey, or soluble proteins, human milk contains more alpha-lactalbumin; cow milk contains betalactoglobulin, which is absent from human milk and to which infants can become intolerant (4). Vitamins and minerals Breast milk normally contains sufficient vitamins for an infant, unless the mother herself is deficient (5). The exception is vitamin D. The infant needs exposure to sunlight to generate endogenous vitamin D – or, if this is not possible, a supplement. The minerals iron and zinc are present in relatively low concentration, but their bioavailability and absorption is high. Provided that maternal iron status is adequate, term infants are born with a store of iron to supply their needs; only infants born with low birth weight may need supplements before 6 months. Delaying clamping of the cord until pulsations have stopped (approximately 3 minutes) has been shown to improve infants’ iron status during the first 6 months of life (6,7). Anti-infective factors Breast milk contains many factors that help to protect an infant against infection (8) including: K immunoglobulin, principally secretory immunoglobulin A (sIgA), which coats the intestinal mucosa and prevents bacteria from entering the cells; K white blood cells which can kill micro-organisms; K whey proteins (lysozyme and lactoferrin) which can kill bacteria, viruses and fungi; K oligosacccharides which prevent bacteria from attaching to mucosal surfaces. Session 2
10 INFANT AND YOUNG CHILD FEEDING-MODEL CHAPTER FOR TEXTBOOKS The protection provided by these factors is unique- 2.3 Animal milks and infant formula ly valuable for an infant.First,they protect without Animal milks are very different from breast milk causing the effects of inflammation,such as fever, in both the quantities of the various nutrients,and which can be dangerous for a young infant.Second, in their quality.For infants under 6 months of age, sIgA contains antibodies formed in the mother's body animal milks can be home-modified by the addition against the bacteria in her gut,and against infections of water,sugar and micronutrients to make them that she has encountered,so they protect against bac- usable as short-term replacements for breast milk in teria that are particularly likely to be in the baby's exceptionally difficult situations,but they can never environment. be equivalent or have the same anti-infective proper- ties as breast milk(13).After 6 months,infants can Other bioactive factors receive boiled full cream milk (14). Bile-salt stimulated lipase facilitates the complete Infant formula is usually made from industrially- digestion of fat once the milk has reached the small intestine(9).Fat in artificial milks is less completely modified cow milk or soy products.During the digested (4). manufacturing process the quantities of nutrients are adjusted to make them more comparable to breast Epidermal growth factor(10)stimulates maturation of milk.However,the qualitative differences in the fat the lining of the infant's intestine,so that it is better and protein cannot be altered,and the absence of able to digest and absorb nutrients,and is less easily anti-infective and bio-active factors remain.Pow- infected or sensitised to foreign proteins.It has been dered infant formula is not a sterile product,and may suggested that other growth factors present in human be unsafe in other ways.Life threatening infections milk target the development and maturation of nerves in newborns have been traced to contamination with and retina (11). pathogenic bacteria,such as Enterobacter sakazakii, found in powdered formula(15).Soy formula con- 2.2 Colostrum and mature milk tains phyto-oestrogens,with activity similar to the Colostrum is the special milk that is secreted in the human hormone oestrogen,which could potentially first 2-3 days after delivery.It is produced in small reduce fertility in boys and bring early puberty in amounts,about 40-50 ml on the first day (12),but is girls (16). all that an infant normally needs at this time.Colos- trum is rich in white cells and antibodies,especially 2.4 Anatomy of the breast sIgA,and it contains a larger percentage of protein, The breast structure(Figure 3)includes the nipple and minerals and fat-soluble vitamins (A,E and K)than areola,mammary tissue,supporting connective tis- later milk(2).Vitamin A is important for protection sue and fat,blood and lymphatic vessels,and nerves of the eye and for the integrity of epithelial surfaces, (17,18) and often makes the colostrum yellowish in colour. The mammary tissue-This tissue includes the alveoli, Colostrum provides important immune protection which are small sacs made of milk-secreting cells,and to an infant when he or she is first exposed to the the ducts that carry the milk to the outside.Between micro-organisms in the environment,and epidermal feeds,milk collects in the lumen of the alveoli and growth factor helps to prepare the lining of the gut ducts.The alveoli are surrounded by a basket of to receive the nutrients in milk.It is important that myoepithelial,or muscle cells,which contract and infants receive colostrum,and not other feeds,at this make the milk flow along the ducts. time.Other feeds given before breastfeeding is estab- lished are called prelacteal feeds. Nipple and areola-The nipple has an average of nine milk ducts passing to the outside,and also muscle Milk starts to be produced in larger amounts between 2 and 4 days after delivery,making the breasts feel fibres and nerves.The nipple is surrounded by the circular pigmented areola,in which are located Mont- full;the milk is then said to have "come in".On the gomery's glands.These glands secrete an oily fluid that third day,an infant is normally taking about 300-400 ml per 24 hours,and on the fifth day 500-800 ml(12). protects the skin of the nipple and areola during lac- tation,and produce the mother's individual scent that From day 7 to 14,the milk is called transitional,and attracts her baby to the breast.The ducts beneath the after 2 weeks it is called mature milk. areola fill with milk and become wider during a feed, when the oxytocin reflex is active
10 Infant and Young Child Feeding – Model Chapter for textbooks The protection provided by these factors is uniquely valuable for an infant. First, they protect without causing the effects of inflammation, such as fever, which can be dangerous for a young infant. Second, sIgA contains antibodies formed in the mother’s body against the bacteria in her gut, and against infections that she has encountered, so they protect against bacteria that are particularly likely to be in the baby’s environment. Other bioactive factors Bile-salt stimulated lipase facilitates the complete digestion of fat once the milk has reached the small intestine (9). Fat in artificial milks is less completely digested (4). Epidermal growth factor (10) stimulates maturation of the lining of the infant’s intestine, so that it is better able to digest and absorb nutrients, and is less easily infected or sensitised to foreign proteins. It has been suggested that other growth factors present in human milk target the development and maturation of nerves and retina (11). 2.2 Colostrum and mature milk Colostrum is the special milk that is secreted in the first 2–3 days after delivery. It is produced in small amounts, about 40–50 ml on the first day (12), but is all that an infant normally needs at this time. Colostrum is rich in white cells and antibodies, especially sIgA, and it contains a larger percentage of protein, minerals and fat-soluble vitamins (A, E and K) than later milk (2). Vitamin A is important for protection of the eye and for the integrity of epithelial surfaces, and often makes the colostrum yellowish in colour. Colostrum provides important immune protection to an infant when he or she is first exposed to the micro-organisms in the environment, and epidermal growth factor helps to prepare the lining of the gut to receive the nutrients in milk. It is important that infants receive colostrum, and not other feeds, at this time. Other feeds given before breastfeeding is established are called prelacteal feeds. Milk starts to be produced in larger amounts between 2 and 4 days after delivery, making the breasts feel full; the milk is then said to have “come in”. On the third day, an infant is normally taking about 300–400 ml per 24 hours, and on the fifth day 500–800 ml (12). From day 7 to 14, the milk is called transitional, and after 2 weeks it is called mature milk. 2.3 Animal milks and infant formula Animal milks are very different from breast milk in both the quantities of the various nutrients, and in their quality. For infants under 6 months of age, animal milks can be home-modified by the addition of water, sugar and micronutrients to make them usable as short-term replacements for breast milk in exceptionally difficult situations, but they can never be equivalent or have the same anti-infective properties as breast milk (13). After 6 months, infants can receive boiled full cream milk (14). Infant formula is usually made from industriallymodified cow milk or soy products. During the manufacturing process the quantities of nutrients are adjusted to make them more comparable to breast milk. However, the qualitative differences in the fat and protein cannot be altered, and the absence of anti-infective and bio-active factors remain. Powdered infant formula is not a sterile product, and may be unsafe in other ways. Life threatening infections in newborns have been traced to contamination with pathogenic bacteria, such as Enterobacter sakazakii, found in powdered formula (15). Soy formula contains phyto-oestrogens, with activity similar to the human hormone oestrogen, which could potentially reduce fertility in boys and bring early puberty in girls (16). 2.4 Anatomy of the breast The breast structure (Figure 3) includes the nipple and areola, mammary tissue, supporting connective tissue and fat, blood and lymphatic vessels, and nerves (17,18). The mammary tissue – This tissue includes the alveoli, which are small sacs made of milk-secreting cells, and the ducts that carry the milk to the outside. Between feeds, milk collects in the lumen of the alveoli and ducts. The alveoli are surrounded by a basket of myoepithelial, or muscle cells, which contract and make the milk flow along the ducts. Nipple and areola – The nipple has an average of nine milk ducts passing to the outside, and also muscle fibres and nerves. The nipple is surrounded by the circular pigmented areola, in which are located Montgomery’s glands. These glands secrete an oily fluid that protects the skin of the nipple and areola during lactation, and produce the mother’s individual scent that attracts her baby to the breast. The ducts beneath the areola fill with milk and become wider during a feed, when the oxytocin reflex is active