Salt taste perception and blood pressure levels in population-based samples: the Circulatory Risk in Communities Study (CIRCS).

To examine the associations of salt perception with salt intake and blood pressure levels in general populations, we performed a cross-sectional study in two communities where salt intake level is different, Akita and Osaka in Japan. Taste perception (detection for certain taste and recognition for salt taste) was determined using a Na-impregnated test strip for 1024 Akita and 1199 Osaka adults aged 30-74 years. The proportions of detection for 0·1 % salt were 61, 62, 79, and 79 % in Akita men, Osaka men, Akita women and Osaka women, respectively. The corresponding proportions of not recognising of 1·6 % salt taste (>1·6 %) were 34, 30, 16 and 21 %. Detection threshold was higher in Akita than in Osaka for women aged 60-74 years, and recognition threshold was lower in Akita than in Osaka for women aged 30-59 and 60-74 years. The high detection (≥0·4 %) and recognition (>1·6 %) thresholds of salt taste were associated with higher salt intake scores for Akita men aged 30-59 years, whose detection and recognition thresholds tended be positively associated with systolic and diastolic blood pressures (SBP and DBP) after adjustment for potential confounders. Among Akita elderly men, detection threshold tended to be positively associated with SBP and DBP, while among Akita middle-aged women, recognition threshold was associated with SBP. In conclusion, the high thresholds of salt perception were inversely associated with salt intake for Akita middle-aged men and with blood pressure levels for Akita middle-aged and elderly men and middle-aged women.