It is unclear whether a substantial decline in malnutrition among infants in developing countries can be achieved by increasing food availability and nutrition counseling without concurrent morbidity-reducing interventions. The study was designed to determine whether provision of generous amounts of a micronutrient-fortified food supplement supported by counseling or nutritional counseling alone would significantly improve physical growth between 4 and 12 mo of age. In a controlled trial, 418 infants 4 mo of age were individually randomized to one of the four groups and followed until 12 mo of age. The first group received a milk-based cereal and nutritional counseling; the second group monthly nutritional counseling alone. To control for the effect of twice-weekly home visits for morbidity ascertainment, similar visits were made in one of the control groups (visitation group); the fourth group received no intervention. The median energy intake from nonbreast milk sources was higher in the food supplementation group than in the visitation group by 1212 kJ at 26 wk (P < 0.001), 1739 kJ at 38 wk (P < 0.001) and 2257 kJ at 52 wk (P < 0.001). The food supplementation infants gained 250 g (95% confidence interval: 20--480 g) more weight than did the visitation group. The difference in the mean increment in length during the study was 0.4 cm (95% confidence interval: -0.1--0.9 cm). The nutritional counseling group had higher energy intakes ranging from 280 to 752 kJ at different ages (P < 0.05 at all ages) but no significant benefit on weight and length increments. Methods to enhance the impact of these interventions need to be identified.