Age-related olfactory and taste changes and interrelationships between taste and nutrition.

This article critically reviews the literature on age-related olfactory and taste changes and the interrelationships between nutrition and taste. Age-related taste alterations are controversial, but there is consensus on an olfactory decline with age. Much of the age-related chemoreceptive research has used inappropriate methodology, thus leaving many findings inconclusive. Changes in the taste system with age may be related to nutrient intake, which in turn can be influenced by taste. Literature on such interrelationships is limited. Vitamins A, thiamin, B-6, B-12, folacin, zinc, and copper are thought to influence taste function. Moreover, those nutrients are of concern in the aged. The use of appropriate methodology is critical not only for the sensory but also for the nutritional aspects, particularly for qualitative and quantitative assessments of nutrient intakes. This review considers the experimental deficiencies (small sample size, inappropriate age range, inadequate psychophysical and stimuli presentation procedures, and poor dietary intake assessment) of studies reported in the literature and suggests major needs for research.