Tải bản đầy đủ - 0 (trang)
Chapter 1. Is breast best? Milk and formula feeds

Chapter 1. Is breast best? Milk and formula feeds

Tải bản đầy đủ - 0trang

Is breast best? Milk and formula feeds


Although breast-feeding is associated with a wide range of sociological and health

benefits, formula milks have been used throughout this century. The use of diluted

cows' milk, and from 1904 'roller-dried' cow milk powder, became popular for

reasons of convenience or, as women entered the work force, of necessity. Following the Second World War aggressive marketing techniques associated their use

with modern affluent societies and large healthy babies. Formula milks were promoted world-wide and propagated through local health care systems, particularly

maternity and baby clinics giving them respectability and the status of medicines.

New mothers were frequently given free samples. Early use of these formulae,

possibly on a trial basis with the sample packs, could lead to incomplete establishment of lactation and hence 'no turning back' for the mother.

From the 1950s through to the late 1970s, formula milks became widely used not

only in the Western world but also in less developed countries where contaminated

water supplies, lack of storage facilities and poor hygiene made their use inappropriate. Poverty and high levels of illiteracy meant that the feeds were often not

made up correctly. The net result was that in the developing countries, infant mortality, directly related to the use of breast milk substitutes, increased significantly

(4, 5).

The issue of the use of these milk formulae in the poorer countries began to receive international attention in the mid-1970s and led in 1981 to the adoption of a

resolution by the World Health Assembly recommending member states to implement a World Health Organization (WHO) code of practice for marketing breast

milk substitutes (3). The substance of this code was to (a) restrict advertising of

FIG. 1

Breast-feedingtrends in the USA (1936-1980) (68-72) and Malaysia (1936-1965) (63).

Is breast best? Milk and formula feeds

breast milk substitutes directly to the public; (b) prevent personnel paid by manufacturers or distributors of these products from 'educating' mothers via the health

care system; (c) stop the distribution of samples to new mothers; (d) eliminate financial inducements to health professionals to promote commercial products; (e)

require formula products to contain the necessary information about the appropriate

use of the product and the superiority of breast milk; and (f) promote breast-feeding

through adequate information and education.

In developing countries a decrease in neonatal mortality and morbidity in breastfed as opposed to formula-fed infants was demonstrated following the adoption of

the WHO code of practice (4, 5). In many Western cultures in the 1970s, breastfeeding rates were slowly increasing for other reasons. Groups were formed to

promote and advise on lactational problems as breast-feeding was perceived to be

healthier for the child and important in the establishment of the mother-infant

bond. The incidence of breast-feeding has subsequently increased in all parts of the

globe (Fig. 1, Table 1).


Breast-feeding statistics in relation to infant age



Duration of feeding

% Breast-feeding

Source a





























1 week

3 months

6 months

1 week

6 months

9 months

6 months

7-12 months

18-27 months

2 months

4 months

6 months

1 months

6 months

15 months

3 months

6 months

9 months

1 week

3 months

9 months

1 month

2 months

6 months

3 months









































































alncludes mixed infant feeding.

bSource a, personal communication from appropriate Ministry of Health or similar authority or data submitted to

W H O by member states (67). Source b, from reference (66).

Is breast best ? Milk and formula feeds


Almost all mothers have the capacity to breast-feed (6). Even in times of drought,

famine and stress such as captivity or ritual fasting such as Ramadan (although

nursing mothers are exempt they often participate), this capacity remains (7). Norwegian statistics show that from 1860 until about 1950 some 75% of mothers

breast-fed their infants at 3 months; there was then a sharp decline to 25% participation, followed by a return to the previous level by the 1980s (73). Records on the

percentage of mothers suckling their infants from the late 1930s reported 77% of

mothers in the USA choosing this method to feed their infants. From the 1940s

until the beginning of the 1970s there was a significant downward trend in breastfeeding as the promotion and variety of available formula feeds gathered momentum. In 1972 it was estimated that less than 25% mothers in the USA breast-fed

their infants (Fig. 1), not necessary for health or social reasons but rather because

the practice was seen as old fashioned. Knowledge that the developed world had

apparently abandoned breast-feeding, combined with the promotion of formulae,

led to women in less developed nations following their example.

The downward trend in breast-feeding did no harm to infants born to mothers of

high socio-economic groups so far as could be established from infant mortality

figures, although the incidence of some conditions (allergies, gastrointestinal, respiratory) did appear to be greater in bottle-fed children. The effect of the use of

formula feeds in lower socio-economic groups and poorer nations, however, was

extremely serious. Rates of infant mortality and serious disease increased with the

decline in breast-feeding as did the incidence of post-partum conception due to the

loss of the contraceptive effect of lactation. Part of the neonatal mortality was attributed directly to the use of contaminated water or incorrect preparation of the

feed leading to dehydration or malnutrition.

As well as the decline in the numbers of infants that were breast-fed, those who

were nursed were often suckled for a significantly shorter period and/or mixed

feeding (breast and bottle) was practised. These infants may not have derived the

full benefit of breast-feeding. Because of these trends, statistics on the number of

breast-fed infants are frequently difficult to interpret. Should an infant count as

being breast-fed only if s/he were fed exclusively for a minimum period (e.g.

3 months) or did a shorter period qualify? Did mixed feeding qualify as breastfeeding? Any statistics on the percentage of women breast-feeding should clearly

define duration and exclusivity. Variation in the criteria applied may yield very

different conclusions.

The decline in the number of breast-fed infants rapidly became a cause for concern for various influential groups including health professionals, child psychologists and government agencies. In less developed nations and lower socioeconomic groups in richer nations, the return to breast-feeding became appreciated

as the safest, most economical way to promote infant health. Consequently, from

Is breast best? Milk and formula feeds

the early 1970s there was a conscious attempt to educate, encourage and promote

breast-feeding. Surveys were performed to discover why and when women stopped

feeding their children and the WHO code of practice was introduced to many

countries. The success of this campaign can be judged by the steady increase in the

numbers of breast-fed infants in Europe and America while the decline in the developing nations was halted.

Currently the incidence of breast-feeding varies greatly between countries; motivation, necessity, and the socio-economic group of the mother all contribute. In less

developed countries, the percentage of women breast-feeding at 3 months is generally over 75% (Table 1). In developed countries, Scandinavia has the highest

number of breast-fed infants and also the longest duration of breast-feeding; in

1980 only 2.5% of Norwegian mothers did not breast-feed on discharge from hospital in contrast to 67% in Belfast (8, 9). The numbers of Scottish mothers breastfeeding at 7 days in 1990-1991 varied between 21.1% and 59.1% in different parts

of the country (10). In the United Kingdom as a whole in 1985-86, 65% of mothers

breast-fed at birth and 22% at 6 months; these figures represented no alteration

from the position 5 years before and may herald another decline (11). In the United

States the number of women who breast-feed is estimated at 61.4% although

marked racial differences exist; 64% of white infants are breast-fed but only 32%

of black infants (12). Variation between and within countries of similar social

structure may be influenced by the degree of promotion of breast-feeding and support available, and the length and flexibility of maternity leave for working mothers. Additionally, the proportion appears to relate to social group, being 87% for

social class 1 (professional) against 43% for class 5 (unskilled) (11). These figures

should be taken into account when comparing the merits of different forms of

feeding. It is now believed that to increase the number of women nursing their infants in areas and groups where the numbers are low and experience limited, a

'warm chain of breast-feeding' is required, i.e. an investment in education and

practical help from experienced health professionals on a one-to-one basis (13).


The benefits of breast-feeding are varied and range from sociological benefits

through to improved health for the young infant and eventually the grown person.

Some are pertinent to all socio-economic groups whilst others relate largely to less

developed nations. A summary of reported advantages of this form of infant feeding appears below:

Clinical benefits

Breast-feeding exclusively for a minimum period of time-is now believed to give

protection from various conditions, some of which may not appear until middle


Is breast best ? Milk and formula feeds


The incidence in children of IgE-associated disorders such as eczema, asthma and

allergic rhinitis is increasing (14, 15). Childhood eczema often precedes the onset

of asthma which may persist into adulthood. As far back as 1936 Grulee and Sanford (16) reported a sevenfold increase in the incidence of eczema in babies fed

cow's milk. Avoiding early exposure to cow's milk as well as to egg, wheat and

beef in the diet could reduce the incidence of eczema and asthma in childhood (17,

18) although other studies have found no difference (19, 20) or a delayed onset of

eczema in breast-fed infants (21). Other environmental factors such as exposure to

cigarette smoke and chemicals, house-dust mite, housing and social conditions are

considered to be more potent than food components in promoting allergies (22, 23).

It is now generally believed that breast-feeding diminishes the incidence of dietrelated hypersensitivity disorders because of its relatively low allergen nature, although breast milk may for some infants still contain sufficient maternally ingested

dietary (dairy based) antigens to promote hypersensitivity reactions. Goat's milk

and soya-based preparations however, are generally believed to have a low allergenic nature and may be used in the absence of breast-feeding where infants cannot

tolerate cow' s milk.

Insulin-dependent diabetes mellitus (IDDM)

Both genetic and environmental components contribute to the aetiology of IDDM.

Susceptibility to IDDM is highly correlated with specific genes (24) but its development may be precipitated by some factor in the infant diet. Various studies have

indicated that infants breast-fed for >3 months have a lower risk of IDDM than

those breast-fed for shorter periods (25, 26) although this view is challenged (27,

28); other environmental factors may also precipitate the condition. Bovine milk

proteins have been reported as being the trigger initiating antibody production and

the initiating of an autoimmune response resulting in IDDM (29, 30). Early cow's

milk exposure has been reported to increase the risk of Type I diabetes by approximately 1.5 in susceptible individuals (31).

Cardiovascular disease

Prolonged breast-feeding (>1 year) has been associated with increased low density

lipoprotein cholesterol and higher death rates from ischaemic heart disease in adult

life (32), although other studies have been inconclusive (33). Breast-feeding elevates plasma cholesterol which is maintained until weaning (34), throughout childhood (35) or even throughout adult life (32). Additionally the HDL/LDL cholesterol ratio is higher in formula-fed than in breast-fed infants at 2 and 6 months of

age (36). A possible explanation for this observation is that the infant absorbs thyroid hormones from breast milk and, through hormonal imprinting, the point of thyroid homeostasis is permanently set at a higher level (37).

Is breast best ? Milk and formula feeds

Neurological status

Children who were breast-fed for a minimum of 3 weeks after birth appeared to

have a small but significantly improved neurological status 9 years later compared

to children who had been formula-fed (38). Breast milk contains longer-chain

polyunsaturated fatty acids which are absent from formula milk and it has been

proposed that these are essential for brain development. Other studies suggest that

the method of feeding has a long-term effect on cognitive development (39,40)


Breast-fed infants are reported to weigh less at 3 and 12 months compared to

weaned infants although body length is not different. Statistical data on weight and

body length suggest that bottle-fed infants are overweight rather than that breastfed infants are underweight (34). The difference in weight rapidly disappears after



Maternal antibodies, immunoglobulins and other protective agents are transferred

to the infant in milk. Agents such as secretory IgA, lactoferrin, interleukin-6, memory T-cells, PAF-acetylhydrolase, lysozyme and antibodies are not produced until

some months after birth (41), and their passage to the infant in breast milk complements the agents transferred while in utero.

Sudden infant death syndrome(SIDS)

Over the past 25 years 11 studies have reported an increased incidence of SIDS in

bottle-fed infants while another 7 found no effect. A recent study (42) found full

bottle-feeding not to be a significant independent risk factor for SIDS but that bottle-fed babies are more likely to have mothers who smoke, to be born preterm and

to come from poorer families. The issue of risk from bottle-feeding appears to remain unresolved.

Sociological benefits

These may be summarised as follows: (a) rapid establishment of infant-mother

bond is believed to be invoked whilst breast-feeding; (b) demand feeding is more

practical and successful when breast-feeding; (c) the infant obtains the right nutritional balance since milk composition changes both with time and on a circadian

rhythm; (d) intelligence quotient at 8 years of age is reported to be increased by

eight points in children who breast-fed as infants, particularly premature infants

(43), although this finding is in contention with results attributed to other social

factors (44, 45). An increased rate in learning disorders has been reported among

formula fed infants which may relate to minor neurological dysfunction in these

children (46).

Is breast best? Milk and formula feeds

Additional benefits pertinent to less developed nations and poorer


(a) Breast-feeding is convenient and low cost, and avoids problems of contamination of feed with polluted water and inadequate sterilisation facilities. Additionally,

breast-feeding negates problems that may be associated with the making up of a

feed to the correct strength. (b) Onset of ovulation is delayed thereby allowing

children to be 'spaced' when other forms of contraception are not available, particularly when demand feeding is practised. (c) Breast-feeding protects against environmental infections especially in the gastrointestinal and respiratory tracts.

Mortality and morbidity rates are higher among bottle-fed infants living in unfavourable and/or disadvantaged conditions. Specific reports, for example, have

shown protective effects of breast milk against Campylobacter jejuni diarrhoea

(milk contains IgA antibodies which neutralise bacterial surface antigens) (47) and

Escherichia coli and salmonella infections (48). In countries with a moderate or

high infant mortality rate, babies fed on formula milk are at least 14 times more

likely to die from diarrhoea than are breast-fed children, and 4 times more likely to

die of pneumonia. Even in countries where infant mortality is low, formula fed infants require hospital treatment up to 5 times more often than those who are fully or

partly breast-fed (49).


The composition of formula milk has changed greatly over the years. Prior to

the second world war the commonest infant 'formula' was diluted cows' milk to

which sugar was added. Available dried formulae were also derived from cows'

milk by the addition of fat and carbohydrate, the product being diluted to resemble

breast milk in its major components. Dietary supplements such as vitamin D and

iron were introduced into formulae although the amount of vitamin D was reduced

after 1957 (50). In 1972 attention was drawn to the high incidence of babies with

gastro-enteritis and dehydration caused by over-concentrated feeds and the high

concentrations of protein and electrolytes in the formulae (51). The UK Department

of Health and Social Security (DHSS) consequently commissioned a study to

examine all aspects of infant nutrition (52). This found that all the fat in formula

milks was butterfat, and manufacturers were directed to change within 2 years

the fat content to short chain fatty acids. Further research into the composition of

human milk prompted a radical alteration of formula milks after 1977. The lipid

component became 90-100% vegetable fat, mainly short chain fatty acids, and

the content of protein, electrolytes, water-soluble and trace elements was reduced

(53). These alterations in the composition of formula milks after 1974 may diminish perceived risks of disorders such as atherosclerosis associated with the use of

the earlier formulations (32). Thus the new generation formula feeds do not neces-

Is breast best? Milk and formula feeds

sarily disadvantage infants when circumstances dictate that breast-feeding may not

confer advantage or may actually be is inadvisable. Some of these are considered


Premature infants

The milk of women delivering prematurely differs from that of mature milk in its

energy, protein and sodium content (all greater) and its carbohydrate content

(lower). Feeding donated human milk to a very low birth-weight infant may lead to

insufficient intakes of protein and energy, since available human milk is likely to

be mature rather than colostrum. Premature infants fed milk from mothers delivering prematurely grow significantly better than those fed mature breast milk (55). In

such circumstances mature milk may be supplemented with protein, fat and carbohydrate derived from human or cow's milk to improve its nutritional content (56,

57). Mature milk may also contain insufficient vitamin D for such infants (58).

Infectious disease

Human immunodeficiency virus (HIV) can be transmitted in breast milk (59, 60)

but the risk of transmission has been difficult to separate from other risk factors

such as prior transmission of the virus to the infant in utero. Evidence suggests a

14% additional risk of transmission of HIV by breast-feeding (60, 61).

Contamination of milk

Breast milk may suffer contamination with insecticides, pesticides and other environmental chemicals including heavy metals (see Chapter 00). As exposure to these

substances also occurs in utero, there is difficult in establishing the extent to which

contamination occurs prenatally or during lactation. Advice issued in Canada encourages women to breast-feed despite the presence of pollutants in milk (54).

Drug utilisation during lactation

Women use a variety of drugs, both prescribed and over-the-counter, in the early

stages of lactation. In surveys 90% (9), 99% (8), and 95% (62) of women were

taking at least one form of medication in the week after delivery. The number of

agents taken in this period reached a maximum of 7 (mean 2.1). Reports from Canada (62), Norway (9), England (63) and Northern Ireland (8, 64) find that the drugs

most commonly prescribed are analgesics, laxatives, vitamins, antimicrobials, antiemetics, sedatives and hypnotics. Table 2 indicates the percentages of hospitalised

women using some of these agents in the immediate post-partum period. After discharge from hospital drug utilisation declines although some 17% of mothers

Is breast best? Milk and formula feeds


Drug utilisation by mothers in maternity wards in Norway (9) and Northern Ireland (8)

Norway a (n = 970)

N. Ireland b (n = 2004)




















Mean number of drugs


Drug class



Antimicrobial (systemic)

Specific drug




a98% mothers breast-feeding.

b33% mothers breast-feeding.

breast-feeding at 4 months take at least one drug per day. Some 5% of mothers who

continued to breast-feed were receiving regular medication for asthma, allergy, hypertension, arthritis, diabetes, epilepsy or migraine (65).

For many years the drugs commonly administered during lactation were either

assumed to be safe or to present hazard to the suckling infant without being subjected to a rational process of analysis. Table 3 shows that warnings are given more

often about drugs use during pregnancy and childhood than during lactation. Consciousness of possible unwanted effects of drugs transmitted in milk appears to be

increasing as caveats or proscriptions on drugs for nursing women listed in the UK

Monthly Index of Medical Specialities (MIMS) rose from 22% in January 1985 to

32% in 1994.

It is common practice carefully to assess the case for any drug that is administered to a pregnant woman. Since most drugs will find their way into milk to some

extent there is an equal case to make a rational assessment of risk to the infant before prescribing medication to a nursing mother. While the quantities of drug transferred may be small in absolute terms, new-born infants have a low capacity to

metabolise and excrete these foreign substances. Now that breast-feeding is again


Warningson the use of medicines


Contraindicated (%)

Special precautions (%)


35.3 (39)

18.0 (15)

14.8 (4)

27.6 (22)

17.3 (18)

Pregnant women

Nursing mothers

Data from MIMS, July 1994. Figures in parentheses refer to MIMS, January 1985.


Is breast best? Milk and formula feeds

popular, it is especially important to attempt a rational evaluation of the medicines

that may be taken with safety during lactation both to avoid harm to the child and

permit the mother to breast-feed with confidence.


1. Illingworth PJ, Jung RT, Howie PW, Leslie P, Isles TE (1986) Diminution in energy expenditure

during lactation. Br. Med. J., 292,437-441.

2. National Research Council (1980) Recommended Dietary Allowances, 9th edn. National Academy of Sciences, Washington DC.

3. WHO (1981) International Code of Marketing of Breast Milk Substitutes. WHO, Geneva.

4. Lepage P, Munyakazi C, Hennart P (1981) Breastfeeding and hospital mortality in children in

Rwanda. Lancet, 2,409-411.

5. Clavano NR (1982) Mode of feeding and its effect on infant mortality and morbidity. J. Trop.

Pediatr., 28, 287-293.

6. Applebaum RM (1975) The obstetrician's approach to the breasts and breast-feeding. J. Reprod.

Med., 14, 98.

7. Prentice AM, Lamb WH, Prentice A, Coward WA (1984) The effect of water abstention on milk

synthesis in lactating women. Clin. Sci., 66, 291-298.

8. Passmore CM, McElnay J, D'Arcy P (1984) Drugs taken by mothers in the puerperium: inpatient

survey in Northern Ireland. Br. Med. J., 289, 1593-1596.

9. Matheson I (1985) Drugs taken by mothers in the puerperium. Br. Med. J., 290, 1588-1589.

10. Ferusin AE, Tappin DM, Girdwood RW, Kennedy R, Cockburn F (1994) Breast feeding in

Scotland. Br. Med. J., 308, 824-825.

l l. Department of Health and Social Security (1988) Present Day Practice in Infant Feeding: Third

Report. HMSO, London.

12. Office of Disease Prevention and Health Promotion (1988) Disease Prevention/Health Promotion

- The Facts. US Dept. Health and Human Services, Bethesda, MD.

13. Editorial (1994) A warm chain for breastfeeding. Lancet, 344, 1239-1241.

14. Burr ML, Butland BH, Kings S, Vaughan-Williams E (1989). Changes in asthma prevalence: two

studies (fifteen years apart). Arch Dis Child, 64, 1452-1456.

15. Mitchell EA (1986). Increasing prevalence of asthma in children. N.Z. Med. J., 96, 463-464.

16. Grulee CG, Stanford HN (1936) The influence of breast and artificial feeding on infantile eczema. J. Pediatr., 9, 223-225.

17. Hill DJ, Hosking CS (1993) Preventing childhood allergy. Med. J. Aust., 158, 367-369.

18. Matthew D, Taylor B, Norman A, Turner M, Soothill J (1977) Prevention of eczema. Lancet, i,


19. Hide DW, Guyer BM. (1981) Clinical manifestations of allergy related to breast and cows' milk

feeding. Arch. Dis. Child., 56, 172-175.

20. Kramer MS, Moroz B (1981) Do breast feeding and delayed introduction of solid foods protect

against subsequent atopic eczema. J. Pediatr., 98, 546-550.

21. Halpern SR, Sellars WA, Johnson RB, Anderson DW, Saperstein S, Reisch JS (1973) Development of childhood allergy in infants fed breast milk, soy or cow's milk. J. Allergy Clin. Immunol., 51, 139-151.

22. Arshad SH, Hide DW (1992) Effect of environmental factors on the development of allergic disorders in infancy. J. Allergy Clin. Immunot., 90, 235-241.

23. Kershaw CR (1987) Passive smoking, potential atopy and asthma in the first five years. J. R. Soc.

Med., 80, 683-688.


Is breast best? Milk and formula feeds

24. Dosch H-M (1993). The possible link between insulin dependent (juvenile) diabetes mellitus and

dietary cow milk. Clin. Biochem., 26, 307-308.

25. Kostraba JN, Cruickshanks J, Lawler-Heavner J, Jobim LF, Rewers MJ, Gay EC, Chase P, Klingensmith G, Hamman RF (1993) Early exposure to cow's milk and solid foods in infancy, genetic predisposition and risk of IDDM. Diabetes, 42,288-295.

26. Mayer EJ, Hamman RF, Gay EC, Lezotte DC, Savitz DA, Klingensmith GJ (1988). Reduced risk

of IDDM among breast-fed children. Diabetes, 37, 1625-1632.

27. Fort P, Lanes R, Dahlem S (1986) Breast feeding and insulin-dependent diabetes mellitus in children. J. Am. Coll. Nutr., 5, 439-441.

28. Scott FW (1990). Cow milk and insulin-dependent diabetes mellitus: is there a relationship? Am.

J. Clin. Nutr., 51,489-491.

29. Martin JM, Daneman D, Dorsch H-M, Robinson B. (1991) Milk proteins in the etiology of insulin-dependent diabetes mellitus. Ann. Med., 23,447-452.

30. Savilahti E, Saukkonen TT, Virtala ET (1993) Increased levels of cow's milk and fl-lactoglobulin

antibodies in young children with newly diagnosed IDDM. Diabetes Care, 16, 984-989.

31. Gerstein HC (1994) Cow's milk exposure and type I diabetes Mellitus. Diabetes Care, 17, 1319.

32. Fall CHD, Barker DJP, Osmond C, Winter PD, Clark PMS, Hales CN (1992) Relation of infant

feeding to adult serum cholesterol concentration and death from ischaemic heart disease. Br.

Med. J., 304, 801-805.

33. Huttenen JK, Saarinen UM, Kostiainen E, Stimes MA (1983) Fat composition of the infant diet

does not influence subsequent serum lipid levels in man. Atherosclerosis, 46, 87-94.

34. Jooste PL, Rossouw LJ, Steenkamp HJ, Rossouw JE, Swanepoel ASP, Charlton DO (1991) Effect of breast feeding on the plasma cholesterol and growth of infants. J. Pediatr. Gastroenterol.

Nutr., 13, 139-142.

35. Sporik R, Johnstone JH, Cogswell JJ (1991) Longitudinal study of cholesterol values in 68 children from birth to 11 years of age. Arch. Dis. Child., 66, 134-137.

36. Kallio MJT, Salmenper~i L, Siimes MA, Perheentupa J, Miettinen TA (1992) Exclusive breastfeeding and weaning: effect on serum cholesterol and lipoprotein concentrations in infants during

the first year of life. Pediatr., 89, 663-666.

37. Phillips DIW, Barker DJP, Osmond C (1993) Infant feeding, fetal growth and adult thyroid function. Acta Endocrinol., 129, 134-138.

38. Lanting CI, Fidler V, Huisman M, Touwen BCL, Boersma ER (1994) Neurological differences between 9-year-old children fed breast milk or formula-milk as babies. Lancet, 344, 13191322.

39. Fergusson DM, Beautrais AL, Silva PA (1982) Breast feeding and cognitive development in the

first seven years of life. Soc. Sci. Med., 16, 1705-1708.

40. Morrow-Tlucak M, Haude RH, Ernhart CB (1988). Breastfeeding and cognitive development in

the first 2 years of life. Soc. Sci. Med., 23, 635-639.

41. Goldman AS (1993) The immune system of human milk: antimicrobial, antiinflammatory and

immunomodulating properties. Pediatr. Infect. Dis. J., 12, 664-671.

42. Gilbert RE, Wigfield RE, Fleming PJ, Berry PJ, Rudd PT (1995) Bottle feeding and the sudden

infant death syndrome. Br. Med. J., 310, 88-90.

43. Lucas A, Morley R, Cole TJ, Lister G, Leeson-Payne C (1992) Breast milk and subsequent intelligence quotient in children born preterm. Lancet, 339, 261-264.

44. Wright P, Deary IJ (1992) Breastfeeding and intelligence. Lancet, 339, 612-613.

45. MacArthur C, Knox EG, Simins KJ (1992) Letter. Lancet, 339, 612-613

46. Menkes JH (1977) Early feeding history of children with learning disorders. Dev. Med. Child

Neurol., 19, 169-171.


Tài liệu bạn tìm kiếm đã sẵn sàng tải về

Chapter 1. Is breast best? Milk and formula feeds

Tải bản đầy đủ ngay(0 tr)