Every day for 12 weeks one group (n=57) received stirfried vegetables, a second (n=62) received a wafer enriched with β-carotene, iron, vitamin C, and folic acid, and a third (n=56) received a non-enriched wafer to control for additional energy intake. The vegetable supplement and the enriched wafer contained 3·5 mg β-carotene, 5·2 mg and 4·8 mg iron, and 7·8 g and 4·4 g fat, respectively. Assignment to vegetable or wafer groups was by village. Wafers were distributed double-masked. In the enriched-wafer group there were increases in serum retinol (mean increase 0·32 [95% Cl 0·23-0·40] μmol/L), breastmilk retinol (0·59 [0·35-0·84] μmol/L), and serum β-carotene (0·73 [0·59-0·88] μmol/L). These changes differed significantly from those in the other two groups, in which the only significant changes were small increases in breastmilk retinol in the control-wafer group (0·16 [0·02-0·30] μmol/L) and in serum β-carotene in the vegetable group (0·03 [0-0·