Promoting healthy growth: what are the priorities for research and action?

Healthy growth from conception through the first 2 y of life is the foundation for adequate organ formation and function, a strong immune system, physical health, and neurological and cognitive development. Recent studies identified several low-cost interventions to address undernutrition during this age period and noted the lower returns on investment of intervening after this critical period. Although these interventions should be implemented widely, it is recognized that existing nutrition solutions, even if universally applied, would only avert a minority fraction of the estimated death and disability due to undernutrition. This paper reviews some of the knowledge and learning needed to close this "impact gap." Five areas are prioritized for future research: 1) study healthy growth from a lifecycle perspective, because maternal, fetal, and newborn outcomes are connected; 2) understand why growth faltering begins so early in breast-fed infants in the developing world; 3) apply new tools and technologies to study long-recognized problems such as the interaction between nutrition and infection; 4) explore new hypotheses for understanding nutrient assimilation and use to discover and develop intervention leads; and 5) understand the role of the environment in healthy growth and the potential synergistic benefits of multi-sectoral interventions. Policymakers are urged to invest in nutrition-specific and -sensitive interventions to promote healthy growth from conception through the first 2 y of life because of their immediate and long-term health and development benefits.