HIGH-ALTITUDE EFFECTS ON HUMAN TASTE INTENSITY AND HEDONICS

Background: The study was conducted on human volunteers taken to 3500 m altitude for a period of 3 wk. Methods: Subjects rated four compound s representing sweet, salty, sour and bitter taste, and the hedonic ma trix in terms of taste threshold, taste intensity, and taste hedonicit y were recorded using category scale. Blood sugar revels were estimate d weekly. Results: An increase in the taste thresholds for glucose and sodium chloride was shown while quinine sulphate and citric acid thre sholds recorded a decrease. The taste intensity ratings showed a linea r relationship with increasing logarithmic molar concentrations of eac h solution, as compared with taste hedonicity which shelved an inverte d 'U' type function. The blood picture did not reveal any change in th e blood sugar level. All the parameters recorded at high altitude (HA) showed a tendency to return to basal values after reinduction to sea level. Conclusion: The study suggests that HA hypoxic stress brings ab out changes in the hedonic responses, primarily an increased palatibil ity for sweetness; we speculate that the mechanism may be anorexia-lin ked nutritional stress.