The Effect of Aging on Taste Thresholds in Korean

Abstract

Background and ObjectivesZZThe sense of taste is one of the most important human senses and plays a critical role in an individual's food preferences and the nutritional status. Proper gustatory function in older people is important for quality of life and enjoyment of food. The objectives of this study was to investigate the effect of aging on taste thresholds in Korean subjects. Subjects and MethodZZOne hundred sixty normal volunteers without smell and taste disorders were investigated. Each subject was given a questionnaire for age, sex, status of smoking and medication. Then, a whole mouth taste test was performed with successive solutions of sucrose, sodium chloride, citric acid, and quinine hydrochloride. ResultsZZOlder subjects (over 50 years) showed worse taste sensitivity compared with younger subjects (age 20-29 years). The detection thresholds of all four basic tastes and the recognition threshold of salty taste of elderly participants were significantly higher than those of young participants. ConclusionZZGustatory sensitivity was found to decrease with age. Especially, older subjects appeared to have a reduced perception of salt, which can alter eating habits, such as intake of more salty foods. Our data can provide preliminary normative values for future investigation of chemosensation in the Korean population.

Effects of aging on taste thresholds: A case of Asian people

“…Effects of aging on sweet threshold values reported in the literature varied among studies. Increases in sweet threshold values have been reported previously in Japanese (Fukunaga et al, 2005;Ogawa et al, 2017) and Korean elderly subjects (Lee et al, 2013). Yoshinaka et al (2015) found no difference in sweet recognition thresholds between Japanese subjects of ages 24-32 and 69-71 years, however, an increase in threshold value was observed after 79 years of age.…”

“…The threshold values tended to increase further in the elderly, albeit not significant ( p > .05). Increases in threshold value of NaCl with aging have been reported in Caucasian (Mojet et al, ), Japanese (Fukunaga et al, ; Yoshinaka et al, ), and Korean (Lee et al, ) subjects. Ogawa et al () suggested that cognitive status was the major factor affecting salty taste sensitivity in the elderly since elderly subjects with lower cognitive scores showed a significantly greater decline in salty taste perception.…”

“…Wardwell et al () found a significant increase in threshold value of caffeine with aging in both male and female subjects, while they found significant increases in threshold values of sucrose, NaCl, and citric acid only in male subjects. Studies that used quinine hydrochloride, another bitter compound, also reported decreased threshold value of the compound with aging in Japanese (Fukunaga et al, ; Ogawa et al, ; Yoshinaka et al, ) and Korean subjects (Lee et al, ).…”

“…Wardwell et al (2009) found a significant increase in threshold value of caffeine with aging in both male and female subjects, while they found significant increases in threshold values of sucrose, NaCl, and citric acid only in male subjects. Studies that used quinine hydrochloride, another bitter compound, also reported decreased threshold value of the compound with aging in Japanese (Fukunaga et al, 2005;Ogawa et al, 2017;Yoshinaka et al, 2015) and Korean subjects (Lee et al, 2013). Table 3 summarizes the extent of decline in taste sensitivity toward various compounds with advancing age, expressed as the ratio of detection and recognition BET values of elderly subjects (60 years) to those of young subjects (20-39 years).…”

“…Most of the studies were conducted with populations in western countries such as the United States (Sanders & Ayers, ; Wardwell, Chapman‐Novakofski, & Brewer, ), The Netherlands (Mojet, Christ‐Hazelhof, & Heidema, ), UK (Kennedy, Law, Methven, Mottram, & Gosney, ), and Brazil (Neumann, Schauren, & Adami, ), among others. Very few studies were conducted with populations in Asian countries and in those few studies the focus has been placed on Korean (Lee, Shin, Rhyu, Kim, & Ye, ) and Japanese (Fukunaga, Uematsu, & Sugimoto, ; Ogawa et al, ; Sasano, Satoh‐Kuriwada, & Shoji, ; Yoshinaka et al, ) populations.…”