In an attempt to figure out the relationship between zinc status and taste acuity of old and young women, dietary zinc intake, urinary zinc excretion, and taste acuity were determined for 118 women. Zinc intake was measured by 2-day food records and food frequency method. Urinary zinc excretion was measured from urine samples collected for twenty four hours. Body fat, lean body mass (LBM), and total body water were measured by bio-impedence. Average dietary zinc intake by food record was 4.15+/-1.33mg (=35% if Korean RDA) for the old women and 5.41+/-2.76mg (=25% of RDA) for young women. When zinc intake was measured by a frequency method, the average intakes of the old and young women were 3.5+/-1.7mg 4.5+/-1.9mg, respectively. It appears that dietary zinc intake of young women was significantly higher than that of the old women. Average urinary zinc excretion of the subjects was 0.27+/-0.16mg in the elderly and 0.24+/-0.13mg in young women, which indicated a marginal zinc status. However, zinc status was not significantly different between old and young women. Correlation analysis indicated that zinc intake and urinary zinc excretion were positively related to BMI and LBM in young women. The old women (m=49) showed significantly higher taste detection thresholds than young subjects (n=47) for both sweet and salty tastes. Recognition thresholds for sodium chloride and sucrose were not significantly different between old and young women. The lower the taste thresholds for salty taste, the higher the average dietary zinc intake. However, taste perception concentration was not related to the urinary zinc excretion level.
Adipose Tissue ; Aged ; Body Water ; Female ; Humans ; Sodium Chloride ; Sucrose ; Taste Perception ; Taste Threshold ; Zinc*

In an attempt to figure out the relationship between zinc status and taste acuity of old and young women, dietary zinc intake, urinary zinc excretion, and taste acuity were determined for 118 women. Zinc intake was measured by 2-day food records and food frequency method. Urinary zinc excretion was measured from urine samples collected for twenty four hours. Body fat, lean body mass (LBM), and total body water were measured by bio-impedence. Average dietary zinc intake by food record was 4.15+/-1.33mg (=35% if Korean RDA) for the old women and 5.41+/-2.76mg (=25% of RDA) for young women. When zinc intake was measured by a frequency method, the average intakes of the old and young women were 3.5+/-1.7mg 4.5+/-1.9mg, respectively. It appears that dietary zinc intake of young women was significantly higher than that of the old women. Average urinary zinc excretion of the subjects was 0.27+/-0.16mg in the elderly and 0.24+/-0.13mg in young women, which indicated a marginal zinc status. However, zinc status was not significantly different between old and young women. Correlation analysis indicated that zinc intake and urinary zinc excretion were positively related to BMI and LBM in young women. The old women (m=49) showed significantly higher taste detection thresholds than young subjects (n=47) for both sweet and salty tastes. Recognition thresholds for sodium chloride and sucrose were not significantly different between old and young women. The lower the taste thresholds for salty taste, the higher the average dietary zinc intake. However, taste perception concentration was not related to the urinary zinc excretion level.
Adipose Tissue ; Aged ; Body Water ; Female ; Humans ; Sodium Chloride ; Sucrose ; Taste Perception ; Taste Threshold ; Zinc*

OBJECTIVETo observe the ultrastructural features of taste pores and taste pits of human taste buds.

METHODSThree samplers obtained randomly from adults were divided into two perts, and transmission electron microscopy and scanning electron microscopy were used to observe the fine structure of taste buds in human circumvallate papillae.

RESULTSThe longer diameter of the taste pores was 1.02 - 7.36 microm, and most of taste pores contained no taste hair and dense material, and the profile of taste pit was triangular.

CONCLUSIONSTaste hair and dense material were seldom observed in most of taste pores.

This study examined salty taste acuity and salty taste preference and sodium intake in relation to zinc nutritional status in 2 rural populations in Korea. And we also examined the main food contributors of their sodium intakes. We enrolled 218 adults (66 men and 152 women) from the Kangneung and Samcheok regions in Korea's Kangwon province in our study conducted from December 2011 to February 2012. Participants from each region were divided into 3 groups based on their serum zinc level (T1: lowest, T2: intermediate, T3: highest). We compared the salty taste acuity and preference, Na index (Dish Frequency Questionnaire for estimation of habitual sodium intake), blood pressure, and intakes of nutrients including sodium by 3 groups of serum zinc level. The results were as follows: a higher serum zinc level indicated a lower sodium intake and Na index (P < 0.05). The salty taste acuity was considerably higher for participants from the Kangneung region than those from the Samcheok region (P < 0.05). And the serum zinc level was significantly higher in participants from the Kangneung region than those from the Samcheok region (P < 0.05). We further divided the participants into 2 groups: those who consumed more zinc than the recommended intake (RI) and the others. We compared salty taste acuity and salty taste preference in the 2 groups. The salty taste threshold and palatable salty taste concentrations were lower for the group with a zinc intake above RI than for the group with zinc intake below the RI. However, the difference was not significant. This study confirms that taste function differs depending on zinc nutritional status. In future, it is required to a large-scale, long-term, prospective study on the correlation between zinc intake, serum zinc levels, and taste perception function and blood pressure.
Adult ; Blood Pressure ; Humans ; Korea ; Male ; Nutritional Status ; Surveys and Questionnaires ; Rural Population ; Sodium ; Taste Perception ; Taste Threshold ; Zinc

Recognition thresholds for NaCl, sucrose, citric acid, and caffeine, as well as the pleasant concentration of NaCl were assessed in 176 males and 312 females aged 50-88 years. Furthermore, relationships among taste sensitivities, taste preferences, and lifestyles were examined. The taste solutions were presented one after the other in ascending order using the sip-and-spit method. For the recognition thresholds of the 4 basic tastes, women perceived significantly lower concentrations than the men. However, the pleasant concentration of NaCl did not show a gender difference. Sensitivities for the 4 basic tastes did not decrease with age in the men, but they did significantly decrease with age for the women, especially for those above 70 years. For men, regular exercise was positively correlated with sensitivities for sour taste and bitter taste, and physical activity was negatively correlated with the pleasant concentrations of NaCl. For women, who had more physical activity, sensitivities for sweet taste and sour taste were lower compared to the others. This study indicates that the sensitivities for 4 basic tastes in water diminished with age, but pleasant salt concentration did not change with age. Further research on pleasant NaCl concentration is required to determine factors affecting salt preference, in order to decrease salt intake in the elderly.
Aged ; Caffeine ; Citric Acid ; Female ; Humans ; Life Style ; Male ; Motor Activity ; Sucrose ; Taste Perception ; Taste Threshold ; Water

Cerebral Cortex ; physiology ; Electroencephalography ; Humans ; Magnetic Resonance Imaging ; Positron-Emission Tomography ; Taste Perception ; physiology

The study aim was to examine the effect of sensory responses of subjects after 6-month dietary sodium reduction with the aid of nutritional education. Fourteen female college students voluntarily restricted their sodium intake for 6 months, during which time they received nutritional education on the low sodium diet. As a control group, 10 students, whose anthropometric measurement, sodium intake behavior, and blood pressure were not different from those of the experimental group, were maintained on a normal diet. For the sensory responses of subjects, the salt taste perception and pleasantness for graded (0.15-1.3%) NaCl solutions were measured by a 9-point hedonic scale. The optimum sodium concentration, urinary sodium excretion, and blood pressure were measured. All the measurements were done at the beginning and end of the experiment. The sensory evaluation revealed an absence of any difference between the two groups in salt taste perception and pleasantness responses at the beginning. After 6-month adaptation, the experimental group subjects showed higher responses to low NaCl solution (0.15, 0.3, 0.5%) in salt taste perception and pleasantness evaluation while the control group subjects exhibited the opposite response. The optimum sodium concentration was reduced from 105.6 mmol to 80.7 mmol (p = 0.015) and the urinary sodium excretion was also reduced from 1,398 mg to 906 mg (p = 0.041) only in the experimental group. Systolic blood pressure was significantly reduced in the experimental group, although there was no correlation between the urinary sodium excretion and blood pressure. The optimum sodium concentration was negatively correlated with the urinary sodium excretion (r = 0.418, p = 0.053), indicating that adaptation to low sodium diet can reduce sodium intake. Further study on the individual responses of subjects on a low sodium diet by periodical evaluation may provide useful data for setting the duration needed to stabilize a lowered appetite for sodium.
Appetite ; Blood Pressure ; Diet ; Female ; Humans ; Sodium ; Sodium, Dietary ; Taste Perception

Taste is closely related to intake of food. Taste perception is also influenced by type of food ingested, and nutrition and health status. Bitter taste plays an important role in the survival of human and animals to avoid probable toxic and harmful substances. Vertebrate animals recognize bitter taste through type 2 taste receptors (T2Rs). Several T2Rs have been expressed extra-oral such as the gastrointestinal tract, respiratory tract, urogenital tract, brain and immune cells, and parts of their functions are being revealed. This review will discuss physiological roles of T2Rs in relation to innate immunity, secretion and smooth muscle contraction expressed in extra-oral cells and tissues, and we summarize relationships between polymorphisms in T2Rs and general or oral diseases. It is not a coincidence that animals pay much genetic costs for taste and smell during evolution.
Animals ; Brain ; Gastrointestinal Tract ; Humans ; Immunity, Innate ; Muscle, Smooth ; Respiratory System ; Smell ; Taste Perception ; Vertebrates

Salt signals in tongue are relayed to the nucleus of the solitary tract (NST). This signaling is very important to determine whether to swallow salt-related nutrition or not and suggests some implications in discrimination of salt concentration. Salt concentration-dependent electrical responses in the chorda tympani and the NST were well reported. But salt concentration-dependency and spatial distribution of c-Fos in the NST were not well established. In the present study, NaCl signaling in the NST was studied in urethane-anesthetized rats. The c-Fos immunoreactivity in the six different NST areas along the rostral-caudal axis and six subregions in each of bilateral NST were compared between applications of distilled water and different concentrations of NaCl to the tongue of experimental animals. From this study, salt stimulation with high concentration (1.0 M NaCl) induced significantly higher c-Fos expression in intermediate NST and dorsal-medial and dorsal-middle subregions of the NST compared to distilled water stimulation. The result represents the specific spatial distribution of salt taste perception in the NST.
Animals ; Axis, Cervical Vertebra ; Chorda Tympani Nerve ; Discrimination (Psychology) ; Rats ; Solitary Nucleus ; Taste Perception ; Tongue ; Water

Excessive dietary salt intake is related to cardiovascular morbidity and mortality. Although dietary salt restriction is essential, it is difficult to achieve because of salt palatability. However, the association between salt perception or salt eating habit and actual salt intake remains uncertain. In this study, we recruited 74 healthy young individuals. We investigated their salt-eating habits by questionnaire and salt taste threshold through a rating scale that used serial dilution of a sodium chloride solution. Predicted 24-hr urinary salt excretions using Kawasaki's and Tanaka's equations estimated dietary salt intake. Participants' mean age was 35 yr, and 59.5% were male. Salt sense threshold did not show any relationship with actual salt intake and a salt-eating habit. However, those eating "salty" foods showed higher blood pressure (P for trend=0.048) and higher body mass index (BMI; P for trend=0.043). Moreover, a salty eating habit was a significant predictor for actual salt intake (regression coefficient [beta] for Kawasaki's equation 1.35, 95% confidence interval [CI] 10-2.69, P=0.048; beta for Tanaka's equation 0.66, 95% CI 0.01-1.31, P=0.047). In conclusion, a self-reported salt-eating habit, not salt taste threshold predicts actual salt intake.
Adult ; Algorithms ; Blood Pressure ; Body Mass Index ; Demography ; Female ; Habits ; Humans ; Linear Models ; Male ; Questionnaires ; Self Report ; Sodium Chloride, Dietary/*urine ; Taste Perception ; Taste Threshold ; Urine Specimen Collection