A study of 227 elderly participants attending Title III-C nutrition programs was conducted to determine food supplement use and its relationship to nutrition knowledge and quality of the diet. Although nutrition knowledge was found to be positively related to the quality of the diet for all subjects, no significant differences were found between supplement and nonsupplement users for these two variables. Although the mean knowledge score was low, positive relationships were found between nutrition knowledge and both education and income for all subjects. Amount of participation in the government-sponsored nutrition centers was negatively correlated with nutrition knowledge.