Book excerpt: On the basis of a comprehensive literature review and analysis, Nutrition During Lactation points out specific directions for needed research in understanding the relationship between the nutrition of healthy mothers and the outcomes of lactation. Of widest interest are the committee's clear-cut recommendations for mothers and health care providers. The volume presents data on who among U.S. mothers is breastfeeding, a critical evaluation of methods for assessing the nutritional status of lactating women, and an analysis of how to relate the mother's nutrition to the volume and composition of the milk. Available data on the links between a mother's nutrition and the nutrition and growth of her infant and current information on the risk of transmission through breastfeeding of allergic diseases, environmental toxins, and certain viruses (including the HIV virus) are included. Nutrition During Lactation also studies the effects of maternal cigarette smoking, drug use, and alcohol consumption.