Ageing and Chemical Senses

Reading glasses and hearing aids are accepted accoutrements of the elderly: It is common knowledge that the visual and auditory senses dim with age. What about the chemical senses of smell and taste? A decline in the ability to appreciate [Page 18](“taste”) food and drink in old age was recognized thousands of years ago and noted in the Old Testament of the Bible (2 Samuel 19:34–35). But in what ways do our perceptions of the volatile and water-soluble molecules we smell and taste change with age? How pronounced is that change? And how early in life does it begin?

This entry addresses these questions, but it is important to recognize first that smell (olfaction) and taste (gustation) are distinct physiological systems. They have different receptor types ...