But most experts agree that providing adequate nutrition to pregnant women and children under 2 years old is crucial  and the Indian program has not homed in on them adequately. Nor has it succeeded in sufficiently changing child feeding and hygiene practices. Many women here remain in ill health and are ill fed; they are prone to giving birth to low-weight babies and tend not to be aware of how best to feed them.

A tour of Jahangirpuri, a slum in this richest of Indian cities, put the challenge on stark display. Shortly after daybreak, in a rented room along a narrow alley, an all-female crew prepared giant vats of savory rice and lentil porridge.

Purnima Menon, a public health researcher with the International Food Policy Research Institute, was relieved to see it was not just starch; there were even flecks of carrots thrown in. The porridge was loaded onto bicycle carts and ferried to nurseries that vet and help at-risk children and their mothers throughout the neighborhood.

Image Children eating at a center in Delhi last December. Credit... Ruth Fremson/The New York Times

So far, so good. Except that at one nursery  known in Hindi as an anganwadi  the teacher was a no-show. At another, there were no children; instead, a few adults sauntered up with their lunch pails. At a third, the nursery worker, Brij Bala, said that 13 children and 13 lactating mothers had already come to claim their servings, and that now she would have to fill the bowls of whoever came along, neighborhood aunties and all. “They say, ‘Give us some more,’ so we have to,” Ms. Bala confessed. “Otherwise, they will curse us.”

None of the centers had a working scale to weigh children and to identify the vulnerable ones, a crucial part of the nutrition program.

Most important from Ms. Menon’s point of view, the nurseries were largely missing the needs of those most at risk: children under 2, for whom the feeding centers offered a dry ration of flour and ground lentils, containing none of the micronutrients a vulnerable infant needs.