Methionine concentration in South African Bantu breast milk.

Although going under different names, the disease commonly referred to as kwashiorkor is of world-wide distribution affecting infants and young children fed on diets habitually deficient in amino-acids. According to Brock & Autret (1952), the syndrome usually includes fatty infiltration, cellular necrosis, or fibrosis of the liver. These authors have reported that in West Africa, fibrosis of the liver may develop in infants at the age of 6 months and possibly even earlier while they are still getting the whole of their food from the breast. It has, therefore, been postulated that a factor or factors may be missing from, or deficient in, the breast milk during the first 6 months of lactation. The fact that experimental methionine deficiency in the rat results in a fatty liver (McHenry & Patterson, 1944) raises the question whether a deficiency of this amino-acid may be involved in the causation of kwashiorkor. It is thus of interest that Auffret & Tanguy (1949) have reported that the breast milk of West African mothers of Dakar is low in methionine. They found a mean value of 16 mg/roo ml., which is unusually low in comparison to the mean value of 29 mg/Ioo ml. quoted by them for American mothers examined by Block (1945). However, more recently, Srinivasan & Ramanathan (1954) have examined the milks of twenty-five Indian mothers, both mothers and babies being apparently healthy, and also of six Indian mothers whose children were suffering from kwashiorkor. No abnormality was apparent; for the milks from the two groups of mothers, they found average values of 29.1 and 30.4 mg methionine/Ioo ml. respectively. In South Africa we have found no abnormality in the mean protein concentration of Bantu breast milk (Walker, Arvidsson & Draper, 1954); moreover, the stigmata of kwashiorkor are not observed in exclusively breast-fed infants. But in view of the report from West Africa, it was thought worth while to carry out determinations of methionine in the breast milk of both Bantu and South African European mothers.