Nutritional status plays a critical role in the prevention and management of many chronic health conditions that are common in the elderly and are likely to become more prevalent as the population ages. This paper highlights several aspects of nutrition that require additional basic science and clinical application research to improve the health and well-being of older adults. Topics addressed are selected demographic and health indices, the uncertain benefits of energy restriction in aged humans compared with other species, the impact of food insecurity on health, the relationship between dietary protein and sarcopenia, the prevention and management of obesity while maintaining muscle mass and functional status, and controversy regarding high intakes of folic acid. Research needs regarding the safety, efficacy, and application of clinical interventions related to these topics also are discussed.