Effects of temperature and volume on measures of mouth dryness, thirst and stomach fullness in males and females.

The immediate post-ingestive effects of temperature on thirst reduction were explored. Thirst was assessed by both ratings and a volume selection task. Supplementary ratings assessed mouth dryness and stomach fullness. All measures were taken before and 0, 2.5 and 5 min after drinking one of four water samples (150 ml/5 degrees C, 400 ml/5 degrees C, 150 ml/22 degrees C or 400 ml/22 degrees C). After 2.5 min, the cold sample produced greater reductions than the warmer sample in (i) the thirst ratings of males who received 400-ml samples, and (ii) the volume selections of females who received 150-ml samples. It is proposed that temperature influenced thirst reduction because of its differential effects on the post-ingestive state of the mouth.