This research study explores the issue of nutrition among older adults. The first part of this study provides background data on the population and aging: demographic and socioeconomic characteristics, health status (multimorbidity, loss of independence), and an overview of professional and informal caregivers. The second part focuses on malnutrition and its health consequences among older adults: osteoporosis and falls. The third part of the study analyzes, on the one hand, dietary behaviors: purchasing behavior, consumption patterns, and knowledge of nutritional guidelines; and, on the other hand, the issue of physical activity: activities practiced, determinants of physical activity, and sedentary lifestyles. The fourth part of the study outlines public health recommendations regarding nutrition, including the development of local policies for home care and support, and the improvement of training for professional caregivers (particularly regarding geriatric nutrition). Finally, the last part of the study presents several existing prevention and health promotion programs in France and abroad (Canada and the USA).