Optimal nutrition is essential for general well being, maintenance of physical and functional capacities and prevention of chronic disease in the elderly. The 5-year longitudinal study, NuAge, was designed to assess the pivotal role of nutrition on physical and cognitive status, functional autonomy and social functioning. A cohort of 1793 men and women, selected from three age groups (68-72, 73-77, 78-82) at recruitment, has been followed annually since 2003-2004. A plurimethodological approach, including basic, clinical, epidemiologic, and social research has been used. Data on various facets of nutritional status (diet, food habits, appetite, anthropometry and body composition), and functional (muscle strength, physical activity, physical and functional capacities and performance), medical (physical, mental and cognitive health, medication) and social data (network, support, participation) are collected by questionnaires or direct measurements. Blood, urine, and saliva samples are also collected and processed for genomic, transcriptomic, proteomic, and biochemical analyses and to study markers of endocrine, immune, and cognitive functions. Selected bio-psycho-social characteristics of the cohort, consumption of macronutrients, and biologic variables are presented, including the impact of intake of certain foods on total antioxidant status. Understanding the aging process as regulated by a modifiable factor such as nutrition should facilitate the development of targeted strategies for promoting successful aging.