Studies on Alterations in Taste Perception of Korean Elderly

ABSTRACT

BACKGROUNDS Recent studies of population trends demonstrate massive increases in both absolute numbers and percentage of our aging population. A large proportion of the population older than 65 years has age-related sensory losses that impair food intakes, overall health, self-sufficiency, and quality of life. Thus, this study was performed investigate the subjective and objective changes of taste perception in Korean elderly. METHODS: The subjects were 22 male and 109 female normal elderly persons aged 55 to 81(mean 70+4.5) years without diabetes mellitus. They were recruited from senior citizen centers in Northern area of Seoul. The agents used for taste measurements are; sodium chloride for salt taste ; sucrose, for sweet; Glacial acetic acid, for sour; and Quinine hemisulfate for buffer. Taste threshold was measured by determining detection and recognition thresholds for all 4 taste qualities by a forced-choice, three-stimulus drop technique. Taste threshold was obtained by dropping solutions on the right sides of the tip of the tongue for salt taste, anterior lateral side for sweet, posterior lateral side, for sour taste, and back of the tongue for buffer taste. RESULTS: Among subjects, 52(40%) had hypertension, 12(9%) heart disease, and 18(14%) hypercholesterolemia. Male subjects had lower detection threshold for salt taste compared to that of females. The subjects with hypercholestrolemia had higher detection threshold for buffer taste(p<0.05). Male subjects had higher recognition threshold for buffer taste compared to that of females(p<0.05). The subjects with hypertension, heart problems, history of smoking, drinking, or medication had no significant changes in detection and recognition taste threshold of 4 different taste. Twenty one(16%) subjects experienced symptoms of dysgeusia, thirty(23%) hypogeusia. None of them reported symptoms of phantogeusia, cacogeusia, or heterogeusia. The subjects with dysgeusia had higher detection threshold for sweet taste(p<0.05). CONCLUSION: Male subjects had lower detection threshold for salt taste and higher recognition threshold for buffer taste compared to those of females in Korean elderly(p<0.05). The subjects with hypercholesterolemia had higher detection threshold for buffer taste(p<0.05), and the subjects with dysgeusia had higher detection threshold for sweet taste(p<0.05). Thus, sex-related salty and buffer taste perception were observed in the elderly and dysgeusia had an effect on sweet taste. These results suggest that these taste perception changes seem to have an influence on nutritional and health status of the elderly and we should consider these taste perception changes to prepare the dietary guidelines for healthy life of the elderly.