Abstract P327: Inter-individual Difference in Sensitivity of Aversive Salt Taste

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Minoru Isomura ◽  
Toru Nabika

Salt is an indispensable nutrient, but excessive amount of salt intake becomes harmful. In order to prevent excessive intake of salt, there is a mechanism to feel high concentration salt as an aversive taste. In recent years, it has clarified that high concentration salt stimulates different taste buds from those sensed by low concentration of salt. In this study, we analyzed relationship between inter-individual difference in sensitivity of aversive salt taste and amounts of daily salt intake. After obtained written informed consent, 1,254 individuals who came annual health checkups were recruited for this study. To test aversive salt taste, five different saline solutions (0.25%, 0.5%, 1%, 1.5%, 2%) were prepared. They started drinking of salt solution from low to high concentration of solutions. In each trial of drinking the salt solution, they were asked whether they were capable of drinking it. When they felt to avoid drinking the salt solution, salt concentration of the solution was recorded as sensitivity of aversive salt taste. Amount of daily salt intake was estimated by using spot urine and by dietary questionnaire. As a result, 784(63%) and 267(21 %) of individuals felt up to the 1.5% and 2% of salt solution as aversive salt taste, respectively. Hence, their sensitivities of aversive salt taste were 1.5% or 2% of salt solutions, respectively. However, resting 203(16%) of individuals showed capability to drink 2% of salt solution. Although we compared sensitivities of aversive salt taste of each individual and daily salt intake that estimated by urine, there were no difference between them. However, daily salt intake that estimated by dietary questionnaire showed clear relationship, in which individuals with the high sensitivities of aversive salt taste consumed the more amount of salt.

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Minoru Isomura ◽  
Toru Nabika

Objective: It is empirically aware that inter-individual differences exist in sensitivity of salt taste. It is assumed that person with reduced sensitivity to salt taste may consume a higher amount of salt than those with a normal sensitivity of salt. The objective of this study is to reveal the relationship between the sensitivity of salt taste and salt intake. Design and method: In this study, we defined salt taste sensitivity by the threshold of the sense of salt taste. Therefore, we defined as reduced sensitivity when individuals were unable to sense salt taste in the concentration that majority of individuals could. Japanese residents who came to annual health checkups were recruited to this study. A series of salt-impregnated taste strips were used to measure salt taste intensity. Each taste strip was impregnated with sodium chloride at concentrations of 0, 0.6, 0.8, 1.0, 1.2, 1.4 and 1.6 g/cm 2 . Daily sodium intake was estimated from sodium excretion in the spot urine using Tanaka’s equation. Results: Among 1,207 participants, 979 (81.1%) individuals were considered to bear normal sensitivity because they were able to detect salt taste by taste strip of 0.6 or 0.8 g/cm 2 . However, 67 (5.6%) individuals were categorized as reduced sensitivity group because they were able to detect it only by the taste strip with the highest amount of salt, or unable to detect salt taste. Daily salt intake of reduced sensitivity group was significantly higher than those in normal sensitivity group (10.3g vs 9.7g, p<0.04). No significant difference was identified in blood presser. Salt taste sensitivity decreased by age, history of smoking and presence of diabetes mellitus. Conclusions: Our study revealed the sensitivity of salt taste is associated with daily salt intake, even adjusted by gender and age. Strict reduction of salt is recommended especially for Smokers or persons with diabetes mellitus, not only because low BP recommendation but also they might pretend to consume salt because of reduced sensitivity of salt taste.


Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Yasuharu Tabara ◽  
Yoshimitsu Takahashi ◽  
Takeo Nakayama ◽  
Fumihiko Matsuda

Excessive salt intake is a risk factor for hypertension. The most reliable method for estimating daily salt intake is measurement of 24-h urinary sodium excretion, while it is inconvenient. Sodium-to-potassium ratio (Na/K) of a urine sample is another index of salt loading. We previously reported that a simple measure of spot urine Na/K might be a representative of salt loading in a cross-sectional setting. Here, we conducted a longitudinal study aiming to clarify a prognostic significance of spot urine Na/K for increasing blood pressure (BP) levels. Study subjects consists of 9,769 general individuals. Among them, individuals whose baseline Na/K was available (n=9,328), who were normotensive at baseline (n=6,392), and who participated in the follow-up measurement (n=5,209) were included in this analysis (51.8±12.9 years old, male: 29.2%). Mean follow-up duration was 5.0±0.5 years. Mean Na/K at baseline was 3.1±1.7, and showed step-wise increase with BP levels (optimal: 3.0±1.6, normal: 3.3±1.8, high normal: 3.4±1.8, P<0.001). Other major factors that were significantly associated with Na/K was fasting time (r=-0.220, P<0.001), and CKD (CKD (n=694): 2.7±1.6, control: 3.2±1.7, P<0.001). Mean SBP was significantly increased during follow-up period (baseline: 116±12, follow-up: 119±15 mmHg), and 805 individuals (15.5%) were newly diagnosed as hypertension (HT). These individuals were significantly older (HT: 60.3±9.9, NT: 50.3±12.8 years), were frequently male (36.4%, 27.9%), and had higher SBP (127±9, 115±11 mmHg) at baseline (P<0.001). In contrast, baseline spot urine Na/K was slightly lower in individuals who developed HT (3.0±1.6, 3.1±1.8, P=0.013), while that measured at follow-up investigation was oppositely higher in hypertensives (3.1±1.8, 2.8±1.5, P<0.001). Multiple linear regression analysis adjusted for the covariates identified baseline Na/K (β=0.108, P<0.001) and changes in Na/K during follow-up period (β=0.222, P<0.001) as independent determinants for future SBP levels. Higher spot urine Na/K, as well as increases in the Na/K levels, was significant determinant for future BP levels. The apparently lower baseline Na/K levels in individuals who developed HT might be due to reverse causality.


2018 ◽  
Vol 19 (4) ◽  
pp. 147032031881001 ◽  
Author(s):  
Monique Tan ◽  
Feng J He ◽  
Graham A MacGregor

The latest Prospective Urban Rural Epidemiology (PURE) study claims that salt reduction should be confined to settings where its intake exceeds 12.7 g/day and that eating less than 11.1 g/day of salt could increase cardiovascular risk. More specifically, Mente et al. suggested that (a) salt intake was positively associated with stroke only when it exceeded 12.7 g/day, (b) salt intake was inversely associated with myocardial infarction and total mortality, and (c) these associations were largely independent of blood pressure. These provocative findings challenge the robust evidence on the role of salt reduction in the prevention of cardiovascular disease and call into question the World Health Organization’s global recommendation to reduce salt intake to less than 5 g/day. However, Mente et al.’s re-analysis of the PURE data has several severe methodological problems, including erroneous estimations of salt intake from a single spot urine using the problematic Kawasaki formula. As such, these implausible results cannot be used to refute the strong evidence supporting the benefits of salt reduction for the general population worldwide.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Long Tan ◽  
Penglin Zheng ◽  
Qingbing Liu

Bentonite, when used as buffer/backfill material in the deep disposal of high-level radioactive waste (HLW), could undergo desiccation shrinkage or even cracking due to the heat released from HLW, impairing the efficiency of the barrier system. Furthermore, in-service buffer materials are inevitably in contact with the groundwater, which sometimes contain high salt concentrations. The groundwater salinity may modify the properties of bentonite and hence affect the process of desiccation and its performance. To investigate this effect, in this study, a series of temperature-controlled desiccation tests was conducted on compacted specimens of Gaomiaozi (GMZ) bentonite preliminarily saturated with two different saline solutions (NaCl and CaCl2) at the concentration varying from 0.5 to 2.0 mol/L. The experimental results indicated that, as the concentration of saline solution increases, the initial saturated water content of bentonite decreases, whereas the residual water content at the completion of the desiccation test increases. The water evaporation rate is reduced for the specimens saturated with a high-concentration saline solution, and CaCl2 has a more significant influence on water evaporation than NaCl. The evolution of cracks on the sample surface during the desiccation process can be divided into four stages: crack growth, maintenance, closure, and stabilization; an increase in the salt concentration effectively inhibits crack development. It was shown that the infiltration of saline solutions alters the microstructure of bentonite by changing the arrangement of clay particles from a dispersed pattern to more aggregate state, which results in a decrease in shrinkage strain and shrinkage anisotropy.


2013 ◽  
Vol 21 (10) ◽  
pp. 1300-1307 ◽  
Author(s):  
Ulla Toft ◽  
Charlotte Cerqueira ◽  
Anne Helms Andreasen ◽  
Betina Heinsbæk Thuesen ◽  
Peter Laurberg ◽  
...  

2019 ◽  
Vol 149 (5) ◽  
pp. 870-876 ◽  
Author(s):  
Nuala Bobowski ◽  
Julie A Mennella

ABSTRACT Background Although salt taste preference is malleable in adults, no research to date has focused on children, whose dietary sodium intake exceeds recommended intake and whose salt taste preferences are elevated. Objective This proof-of-principle trial determined whether 8-wk exposure to low-sodium cereal (LSC) increased children's acceptance of its taste and changed their salty and sweet taste preferences. Methods Children (n = 39; ages 6–14 y; 67% female) were randomly assigned to ingest LSC or regular-sodium cereal (RSC) 4 times/wk for 8 wk. The cereals, similar in sugar (3 g/cup compared with 2 g/cup) and energy content (100 kcal/cup) yet different in sodium content (200 mg sodium/cup compared with 64 mg sodium/cup), were chosen based on taste evaluation by a panel of children. Mothers completed daily logs on children's cereal intake. At baseline and after the exposure period, taste tests determined which cereal children preferred and measured children's most preferred amount of salt (primary outcomes), and most preferred amount of sucrose and salt taste detection thresholds (secondary outcomes). Repeated measures ANOVAs were conducted on primary and secondary outcomes, and generalized estimating equations were conducted on amount of cereal ingested at home over time. Results Both treatment groups accepted and ate the assigned cereal throughout the 8-wk exposure. There were no group × time interactions in salt detection thresholds (P = 0.32) or amount of salt (P = 0.30) and sucrose (P = 0.77) most preferred, which were positively correlated (P = 0.001). At baseline and after the exposure, the majority in both groups preferred the taste of the RSC relative to LSC (P > 0.40). Conclusions Children showed no change in salt preference but readily ate the LSC for 8 consecutive weeks. Findings highlight the potential for reducing children's dietary salt intake by incorporating low-sodium foods in the home environment without more preferred higher-salt versions of these foods. This trial was registered at clinicaltrials.gov as NCT02909764.


Nutrients ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 2026
Author(s):  
Karen Elizabeth Charlton ◽  
Aletta Elisabeth Schutte ◽  
Leanda Wepener ◽  
Barbara Corso ◽  
Paul Kowal ◽  
...  

Given a global focus on salt reduction efforts to reduce cardiovascular risk, it is important to obtain accurate measures of salt intake on a population level. This study determined firstly whether adjustment for intra-individual variation in urinary sodium (Na) excretion using three repeated 24 h collections affects daily estimates and whether the use of repeated spot urine samples results in better prediction of 24 h Na compared to a single collection. Twenty three community-dwelling men and women from South Africa (mean age 59.7 years (SD = 15.6)) participating in the World Health Organization Study on global AGEing and adult health (WHO-SAGE) Wave 3 study collected 24 h and spot early morning urine samples over three consecutive days to assess urinary Na excretion. INTERSALT, Tanaka, and Kawasaki prediction equations, with either average or adjusted spot Na values, were used to estimate 24 h Na and compared these against measured 24 h urinary Na. Adjustment was performed by using the ratio of between-person (sb) and total (sobs) variability obtained from repeated measures analysis of variance. Sensitivity of the equations to predict daily urinary Na values below 5 g salt equivalent was calculated. The sb/sobs for urinary Na using three repeated samples for spot and 24 h samples were 0.706 and 0.798, respectively. Correction using analysis of variance for 3 × 24 h collections resulted in contraction of the upper end of the distribution curve (90th centile: 157 to 136 mmoL/day; 95th centile: 220 to 178 mmoL/day). All three prediction equations grossly over-estimated 24 h urinary Na excretion, regardless of whether a single spot urine or repeated collections corrected for intra-individual variation were used. Sensitivity of equations to detect salt intake equivalent values of ≤5 g/day was 13% for INTERSALT, while the other two equations had zero sensitivity. Correcting for intra-individual variability in Na excretion using three 24 h urine collections contracted the distribution curve for high intakes. Repeated collection of spot samples for urinary Na analysis does not improve the accuracy of predicting 24 h Na excretion. Spot urine samples are not appropriate to detect participants with salt intakes below the recommended 5 g/day.


1998 ◽  
Vol 79 (2) ◽  
pp. 911-921 ◽  
Author(s):  
Mamoun A. Kloub ◽  
Gerard L. Heck ◽  
John A. Desimone

Kloub, Mamoun A., Gerard L. Heck, and John A. DeSimone. Self-inhibition in Ca2+-evoked taste receptors: a novel tool for functional dissection of salt taste transduction mechanisms. J. Neurophysiol. 79: 911–921, 1998. Rat chorda tympani (CT) responses to CaCl2 were obtained during simultaneous current and voltage clamping of the lingual receptive field. Unlike most other salts, CaCl2 induced negatively directed transepithelial potentials and gave CT responses that were auto-inhibitory beyond a critical concentration. CT responses increased in a dose-dependent manner to ∼0.3 M, whereafter they decreased with increasing concentration. At concentrations where Ca2+ was self-inhibitory, it also inhibited responses to NaCl, KCl, and NH4Cl present in mixtures with CaCl2. Ca2+ completely blocked the amiloride-insensitive component of the NaCl CT response, the entire KCl-evoked CT response, and the high-concentration-domain CT responses of NH4Cl (≥0.3 M). The overlapping Ca2+-sensitivity between the responses of the three Cl− salts (Na+, K+, and NH+ 4) suggests a common, Ca2+-sensitive, transduction pathway. Extracellular Ca2+ has been shown to modulate the paracellular pathways in different epithelial cell lines by decreasing the water permeability and cation conductance of tight junctions. Ca2+-induced modulation of tight junctions is associated with Ca2+ binding to fixed negative sites. This results in a conversion of ion selectivity from cationic to anionic, which we also observed in our system through simultaneous monitoring of the transepithelial potential during CT recording. The data indicate the paracellular pathway as the stimulatory and modulatory site of CaCl2 taste responses. In addition, they indicate that important transduction sites for NaCl, KCl, and NH4Cl taste reception are accessible only through the paracellular pathways. More generally, they show that modulation of paracellular transport by Ca2+ in an intact epithelium has functional consequences at a systemic level.


Sign in / Sign up

Export Citation Format

Share Document