At each school, assignment to the 4 color-coded treatment groups
was done randomly. Each child received 2 meals/d, 6 d/wk, for 9
wk. Meals contained vegetables, fruit, a protein source, and rice or
rice noodles. The difference between the meals provided to the 4
groups was in the amount and source of vitamin A. The vegetable
group (green) received carotene-rich, dark-green, leafy vegetables
and carrots; the fruit group (purple) received carotene-rich fruit; the
retinol-rich group (red) received retinol-rich protein sources; and
the low-retinol, low-carotene group (white) received food low in
both retinol and carotene