Background: The study was conducted on human volunteers taken to 3500 m altitude for a period of 3 wk.
Methods: Subjects rated four compounds representing sweet, salty, sour and bitter taste, and the hedonic matrix in terms of taste threshold, taste intensity, and taste hedonicity were recorded using category scale. Blood sugar levels were estimated weekly.
Results: An increase in the taste thresholds for glucose and sodium chloride was shown while quinine sulphate and citric acid thresholds recorded a decrease. The taste intensity ratings showed a linear relationship with increasing logarithmic molar concentrations of each solution, as compared with taste hedonicity which showed an inverted 'U' type function. The blood picture did not reveal any change in the 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 about changes in the hedonic responses, primarily an increased palatibility for sweetness; we speculate that the mechanism may be anorexia-linked nutritional stress.