Final answer:
Ageing commonly affects the senses of taste and smell by reducing their acuity, contrary to improving sensitivity. This decline, noticeable after the age of 50, results from physiological changes in the sensory receptors and may also affect the sense of touch.
Step-by-step explanation:
Changes in the senses of taste, smell, and touch are common as individuals age. The sense of taste and smell often becomes less acute after the age of 50. This is because taste, gustation, and smell, or olfaction, rely on receptors bonding to stimulus molecules entering the body, and their number and sensitivity can decline as part of the ageing process. It is known that children can have a sharper sense of taste, finding some flavours too intense, while older adults might find these same flavours to be bland. This can be due to various factors including a reduction in the number of taste buds, changes in saliva production, and the cumulative effect of environmental factors like smoking or pollution affecting the olfactory system over time. While the taste of food can be enhanced by adding certain ingredients like salt, the overall sensitivity to taste typically diminishes with age.
Contrary to this, the sense of touch does not generally improve with age; sensitivity to touch may also decrease due to factors such as reduced blood flow and changes in the skin and nervous system. Hence, the statement, 'All three senses become more sensitive with age,' is incorrect. Instead, ageing can lead to a decline in these sensory abilities, affecting an individual's ability to enjoy food and detect environmental cues.