The Nutrition and Health Characteristics of Low-Income Populations study examined longrun average, or "usual" intakes of 10 key nutrients and dietary components: energy intake, vitamin C, iron, zinc, calcium, total fat, saturated fat, cholesterol, sodium, and fiber. Results were estimated for participants in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), Food Stamp Program (FSP) participants, school-age children, and older adults. Because the recommendations for nutrient intake have been under revision, intake distributions are useful for estimating the prevalence of adequate intake under different standards. The study provides a baseline from which to monitor the nutrition and health characteristics of each group over time and to identify priorities for further research.