The Pregnancy and Birth to 24 Months Project: a series of systematic reviews on diet and health.

Nutrition exposures during the earliest stages of life are integral to growth and development and may continue to affect health through adulthood. The purpose of the Pregnancy and Birth to 24 Months (P/B-24) Project was to conduct a series of systematic reviews on diet and health for women who are pregnant and for infants and toddlers from birth to 24 mo of age. The P/B-24 Project was a joint initiative led by the USDA and the US Department of Health and Human Services. The USDA's Nutrition Evidence Systematic Review team, previously known as the Nutrition Evidence Library, carried out the series of systematic reviews in collaboration with programmatic and scientific experts. Systematic review questions were prioritized based on federal policy, program, or guidance needs, potential to support the development of healthy dietary intake, and public health importance. Systematic reviews were conducted on specific topics related to dietary intake before and during pregnancy, infant milk feeding practices, complementary feeding, flavor exposures, and infant/toddler feeding practices. Across the reviews, relationships were observed between P/B-24 diet exposures and a variety of outcomes of public health importance. Evidence showed links between dietary intake before and during pregnancy, during the period of human milk or infant formula feeding, and through introduction of complementary foods and beverages and health outcomes. Additionally, the reviews on flavor exposure and infant/toddler feeding practices highlight the importance of maternal diet during pregnancy and lactation and caregiver feeding strategies and practices. Systematic reviews are an important tool to inform our understanding of the body of evidence related to diet and health, and scientists can use the P/B-24 Project reviews to continue to advance research in these areas.