Riboflavin status in infants born in rural Gambia, and the effect of a weaning food supplement.

Riboflavin status was measured in infants between birth and two years of age, by the erythrocyte glutathione reductase (NAD(P)H2: glutathione oxidoreductase, EC 1.6.4.2) test on finger-prick blood samples. The infants were living in three rural Gambian villages: Keneba, Manduar and Kanton Kundar; those in Keneba were receiving a weaning food supplement between three and 12 months, which provided 0.15 to 0.20 mg riboflavin per day, in addition to their normal intake from breast milk and locally available weaning foods, which provided 0.13 to 0.21 mg/day over the same age range. On the basis of currently accepted criteria of biochemical normality, the unsupplemented infants were born deficient and, in the absence of a supplement, remained so throughout their first two years of life, with only a minor, short-lived improvement during the first few months. In the supplemented group, however, riboflavin status fell within normal limits for the duration of the supplement, but rapidly deteriorated again once the supplement was withdrawn. It is concluded that infants born to deficient mothers are usually deficient at birth, and remain so throughout suckling and weaning on to locally available foods. The daily requirement, to achieve satisfactory biochemical status, is thus greater than 0.13 to 0.21 mg/day, and probably approaches 0.4 mg/day, for most individuals up to the age of one year.