A novel study on recently discovered fatty acid taste detection threshold among young lean and overweight individuals

Background: It is likely that the sense of taste evolved to alert humans to the nutritive or poisonous nature of possible foods. This study has been undertaken to unravel and highlight a possible relationship between the fat taste threshold and obesity, especially among young population. Aims and Objectives: The aim of the study was to detect the fat taste threshold in young lean and overweight individuals and to compare the threshold in these individuals with age- and sex-matched normal individuals. Materials and Methods: The taste threshold for fat was detected in 50, normal (Body mass index [BMI] (18.5–24.9 kg/m2), lean (BMI <18.5 kg/m2), and overweight individuals (BMI of 25.0–29.9 kg/m2) of both sexes with the age between 18 and 30 years. The statistical analysis was done using Analysis of variance test. Results: Young lean individuals could detect the fatty acid taste at the lower concentration compared to overweight individuals, who detected at higher concentration (P < 0.01). Conclusion: Lean male and female showed a significant taste detection threshold for fat at low concentration compared to overweight male and female as well as with normal individual. Fatty acid taste detection is very important in day-to-day life for the disease-free life.

A study on physiological taste threshold in hyperthyroidism

Background: Taste is the perception produced when a substance in the mouth reacts chemically with taste receptors located on taste buds in the oral cavity. The five basic taste modalities are sweet, salt, sour, bitter, and umami. Disorders of taste can result from various diseases and use of various drugs. Hyperthyroidism is one among them which affects the taste sensation and threshold. Aim and Objectives: The study was conducted to assess the physiological taste threshold for the five primary taste modalities in hyperthyroid patients and to compare their taste thresholds with that of the normal healthy controls. Materials and Methods: Investigations were carried out in 30 hyperthyroid patients aged between 20 and 50 years and in age, sex, and anthropometrically matched control groups of 30, who were apparently healthy. The statistical analysis was done by student’s t-test. Results: There is no difference in the physiological threshold of the all the basic tastes but salt. A significant (P < 0.05) increase in the taste threshold for salt taste can be seen in hyperthyroid patients compared to that of controls. Conclusion: The threshold for salt taste was altered in hyperthyroidism, which can be detected by proper screening. Taste dysfunction leads to reduced food intake and poor nutrition. Proper treatment and counseling can help them to get back their normal taste threshold along with normal thyroid status.

A comparative study on the physiological taste threshold in hypothyroidism and normal controls

Background: Taste, one of the five special senses, is the sensory impression of various substances on the tongue. There are five basic taste modalities such as sweet, salt, sour, bitter, and umami. The physiological taste threshold of the individual gets altered in hypothyroidism. Aims and Objectives: The present study was undertaken to test and compare the physiological taste threshold for the five primary taste modalities such as umami, salt, sweet, sour, and bitter in hypothyroid patients and the normal healthy controls. Materials and Methods: Thirty hypothyroid patients aged between 20 and 50 years and 30 age, sex, and anthropometrically matched apparently healthy individuals as control were included in the study. The tests for the threshold of all the five primary tastes were performed in both the groups and the results were compared. Results: The taste threshold for the sweet taste modality has been increased significantly (P < 0.05) in hypothyroid patients compared to controls. No difference could be observed in case of other taste modalities. Conclusion: The significant increase in the physiological taste threshold of sweet modality in hypothyroid patients compared to the controls suggests that hypothyroid patients may have a decreased sensitivity for the sweet taste. Thus, the taste dysfunction should be detected in them by proper screening. Timely management/treatment and counseling can help them to get back their normal taste threshold along with attaining the euthyroid status.

Association between salt taste sensitivity threshold and blood pressure in healthy individuals: a cross-sectional study

ABSTRACT BACKGROUND: Hypertension is an important public health problem. Overweight and high salt intake are risk factors for its development. OBJECTIVE: To evaluate the association between salt taste sensitivity threshold (STST) and blood pressure (BP) in healthy adults. DESIGN AND SETTING: Cross-sectional study conducted in a private institution. METHODS: 104 healthy adults (aged 18-59 years) were evaluated. Sociodemographic, clinical and dietary data were collected. Nutritional status and BP were assessed using body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP) and diastolic blood pressure (DBP). STST was assessed using graded saline solutions with sodium chloride concentrations ranging from 0.228 to 58.44 g/l. Identification of salty taste in solutions ≥ 3.652 g/l was used as the cutoff point for high STST. RESULTS: Participants with high STST presented higher daily average intakes for energy (2017.4 ± 641.5 versus 1650.5 ± 357.7 kcal/day; P = 0.01) and sodium (3070.2 ± 1195.1 versus 2435.2 ± 963.6 mg/day; P = 0.01) and higher BMI (P = 0.008) and WC (P = 0.002). After adjustment for age, sex, sodium and potassium intake, WC and family history of hypertension, the averages for SBP and DBP in subjects with high STST were higher than in those with normal STST (SBP: 138.2 ± 1.7 versus 119.7 ± 0.9 mmHg; P < 0.001; DBP: 81.2 ± 1.9 versus 75.1 ± 1.0 mmHg; P = 0.008). CONCLUSION: High STST was associated with elevated blood pressure in healthy adults, regardless of other risk factors for hypertension.

Preparation and evaluation of azithromycin-loaded microspheres for oral administration / 中国药科大学学报

@#To mask the bitterness of azithromycin（AZI） and improve patient compliance, an AZI-loaded microsphere (AZI-EC MS) for oral administration was prepared by O/W emulsion solvent evaporation with ethylcellulose (EC) as carrier. The release profiles and taste-masking effect of AZI-EC MS were preliminarily assessed. Its physical properties and morphology were then investigated by differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). The results indicated that the polymer weight of EC could influence the drug release behavior. With a drug polymer ratio of 1∶1 and mixed EC (N22/T10, 7∶3) as carrier, the cumulative release of AZI-EC MS at 0.5 h was less than 40% and reached 90% at 8 h; the drug loading efficiency of microspheres was (48.95 ± 0.86)% with smooth spherical morphology. The AZI bitterness threshold is 9.93 μg/mL with a strong bitter taste, which indicated a better taste masking effect. Therefore, AZI-EC MS prepared in this study can mask AZI bitterness and improve patient compliance, setting the stage for the research of new AZI preparations.

Comparison of Salt Taste Threshold and Salt Intake between Hypertensive and Normotensive Group / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Salt-taste threshold can influence salt appetite, and is thought to be another marker of sodium intake. Many studies have found an association between sodium intake and blood pressure. The aim of this study was to compare the salt-taste threshold and salt intake between hypertensive and normotensive groups. SUBJECTS AND METHOD: One hundred twenty volunteers (51 men and 69 women) who did not take antihypertensive medications were evaluated. First, a questionnaire, which included questions regarding demographic information and preference of salty taste, was conducted, and 24-hour ambulatory blood pressure was checked. Then salt taste threshold was measured by assessing the ability of the subjects to discern the taste of salt in graded solutions of saline. Lastly, 24-hour urinary sodium was measured in a 24-hour urine collection. RESULTS: The salt taste threshold and taste preference for salt were slightly higher in hypertensive group. There was slightly higher salt intake measured as 24-hour urinary sodium in the hypertensive group, compared with the normotensive group. However, there were no significant differences in salt taste threshold, preference of salty taste, and salt intake between the normotensive and the hypertensive groups. CONCLUSION: The threshold of salt taste was not related to sodium intake and hypertension status. These results suggest that the development of hypertension depends on the complex interaction of factors such as genes and environmental factors rather than sensory factors like taste threshold and taste preference.

Differences in Taste Thresholds According to Sex and Age Groups in Korean / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The aim of the study was to compare the gustatory function between age-matched men and women in Korean subjects. SUBJECTS AND METHOD: Healthy non-smoking volunteers without smell and taste disorders were investigated. Thirty-nine men and women of the same age group were evaluated for gustatory function. Whole mouth taste test was performed with successive solutions of sucrose, sodium chloride, citric acid, and quinine hydrochloride. The electrical taste thresholds were measured using an electrogustometer for four different sites in the oral cavity, i.e., both sides of anterior and posterior tongue. RESULTS: Female subjects had lower mean values of detection and recognition thresholds for all of the four tastes than male subjects, although these results did not reach statistical significance except for the detection threshold for salt and the recognition threshold for quinine. In electrogustometry, thresholds in the posterior tongue of glossopharyngeal nerve area were significantly higher for men than women. CONCLUSION: Men had higher taste threshold than women of the same age category. For additional information on the effects of gender and aging on taste thresholds, further studies including a large number of well-controlled subjects are essential.

Not Salt Taste Perception but Self-Reported Salt Eating Habit Predicts Actual Salt Intake

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.

The Effect of Aging on Taste Thresholds in Korean / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The 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 METHOD: One 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. RESULTS: Older 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. CONCLUSION: Gustatory 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.

Physiological taste threshold in type 1 diabetes mellitus.

The sense of taste is one of the important oral chemical senses that play a critical role in human life. The taste threshold increases by number of factors such as age, local and systemic disease like diabetes, consumption of alcohol, smoking. The aim of the present study was to assess the relationship between taste threshold in type 1 diabetics and non diabetics for four basic taste modalities (i.e. sweet, salt, sour and bitter). We studied 70 cases of type 1 diabetic and 70 non diabetics. The taste threshold was evaluated using 7 different serially half diluted concentrations of glucose (2.00 M–0.031 M), Nacl (1.00 M– 0.0156 M), citric acid (0.05 M– 0.0007 M) and quinine sulphate (0.001 M–0.000015 M). A significant increase in taste threshold for sweet (P<0.0001), salt, sour and bitter (P<0.001) in type 1 diabetic was observed. We concluded that taste sensation was reduced in type 1 diabetics.

Clinical Investigations in Patients with Taste Disorder / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Taste disorders have not received sufficient attention by otolaryngologists and only a few studies have documented the clinical characteristics of taste disorders. We therefore analyzed the characteristics of patients with taste disorders who visited our Taste and Smell Clinic over a 3-year period. SUBJECTS AND METHOD: Sixty patients with taste disorders were investigated. The efficacy of treatment was evaluated according to the age, sex, duration of symptom, cause, and severity of taste disorder. RESULTS: Sixty percent of patients visited the clinic within 6 months of the onset of decrease in taste sensation. Multiple etiology was more common than single etiology. Taste disorder due to olfactory disorder was the most frequent etiology, followed by drug induced taste disorder and taste disorder due to zinc deficiency. Sixty percent of the patients experienced improvement of the taste abnormality. The efficacy of treatment decreased with increasing severity of taste disorder at the initial visit. CONCLUSION: Careful history taking and physical examination are needed for determination of the cause of any taste abnormality. The site and severity of dysgeusia should be determined through the chemical and electrical taste threshold test. Treatment should direct toward the causative abnormality, if possible.

The Effect of Lifestyle, Dietary Habit, Food Preference and Eating Frequency on Sweet Taste Sensitivity and Preference of the Middle School Students

This study was conducted to determine factors affecting detection threshold and the optimally-preferred concentration for sweet taste, since investigation into factors decreasing sensitivity or increasing preference for sweet taste is important to prevent overconsumption of simple sugar. Subjects were 70 first-grade middle school students in the Gyeonggi- Do. The detection threshold concentration of sucrose solution and the optimally-preferred sucrose concentration of omija jelly were determined by sensory evaluation. A self-administered questionnaire was used to obtain the information regarding health-related lifestyle practices, dietary habits, preference for and eating frequency of Westernized foods and frequencies of eating foods other than home-made. The detection threshold concentration of sucrose solution and the optimally-preferred sucrose concentration of omija jelly of the subjects were 0.204% and 14.44%, respectively. Subjects who exercise less ( or = 3/week), type of breakfast rather than traditional Korean meal and frequent eating out and buying foods from school tuck-shop tended to have higher sweet taste threshold. There was significant positive correlation between the sucrose threshold concentration and fried chicken preference or eating frequency of hamburger. Those who exercise less ( or = 4 out of 10) behavioral or psychological stress symptoms and who had early getting-up time (before 7 am). There was significant positive correlations between the optimally-preferred sweetness of omija jelly and pizza preference, instant noodle eating frequency or sum of eating frequencies of five fast foods. From the results of this study, it was suggested that middle school students should make efforts to stop skipping meals, exercise more, eat Korean traditional breakfast and reduce the frequencies of eating out and using instant/fast foods in order to prevent overconsumption simple sugar.

Changes of Taste Function after Tonsillectomy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The objective of the study was to investigate changes in taste sensation after tonsillectomy by using filter paper discs (FPD )method and visual analogue scale (VAS ). MATERIALS AND METHOD: Thirty healthy adult patients who had undergone tonsillectomy were included in this study. A taste test using the FPD method and a subjective rating of taste function based on VAS were performed preoperatively and postoperatively on the 14th day. Serum zinc level was checked at the operation day. Operative findings regarding adhesion, size, and inflammation were recorded. RESULTS: Four patients (13.3%)showed 2 points above the elevated taste identification threshold (TIT). Nine patients (30%)felt their taste sensitivity decreased more than 2 points in the VAS system after the operation. At the postoperative 2 week period, there were significant decrease in sensitivity to sweet and salty TIT, tendency to decrease in sour TIT, and tendency to increase in bitter TIT. The mean VAS decreased significantly. The changes in TIT (dTIT )to each taste stimuli and the changes of VAS (dVAS) had no significant correlation. The degree of adhesion, size and inflammation of the tonsil and serum zinc level showed no significant correlation with dTIT to each taste stimuli and dVAS. CONCLUSION: At 2 weeks after tonsillectomy, the taste sensitivity generally increased except for bitter stimuli. But this changes were not correlated with subjective taste assessment, which may be due to various postoperative discomforts. Tonsil adhesion, size, inflammation and serum zinc level did not influence acute postoperative changes in taste function.

The Changes of Taste Sense after the Injury of Unilateral Chorda Tympani Nerve during Middle Ear Surgery / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Currently, the changes of taste sensation after unilateral injury of chorda tympani nerve during middle ear surgery remains unclear, particularly in objective methods, like threshold to each taste stimulus. This study aims to evaluate the objective changes of taste threshold according to the degrees of injury of chorda tympani nerve. MATERIALS AND METHODS: In 36 patients who underwent middle ear surgery, the degrees of injury were described as "intact", "stretched" and "sacrificed". The taste threshold to citric acid, NaCl, and sucrose were measured preoperatively, and 1 week, 1 month, 3 months after surgery. Subjective changes of taste sensation were questioned together. The amount of changes in threshold according to the degree of injury were statistically analyzed. RESULTS: There were no significant differences of threshold according to the degrees of injury in each taste. Several patients documented subjective taste changes, such as hypogeusia and parageusia. But there were no relationship between subjective and objective findings. CONCLUSION: These results suggest the probability of some compensatory mechanism after unilateral injury of chorda tympani nerve. There might be some discrepancy between taste threshold and real-world taste sensation.