The Power of Taste
“Last scene of all, that ends this strange eventful history, is second childishness and mere oblivion, sans teeth, sans eyes, sans taste, sans everything.”
Sans taste, of course, means without taste and it’s interesting to look at the relevance of taste to the nutritional status of service users.
The tastes of bitter, salt, sour and, to a lesser extent sweet, are affected by ageing. Although the mechanism is unclear it is thought there may be a progressive loss in the number and sensitivity of taste buds, as well as a change in the relative proportion of taste buds for bitter/sour tastes. In most cases, the sense of taste is not totally absent (ageusia) in older people but rather is reduced (hypogeusia) or distorted (dysgeusia).
Taste changes are amplified in service users taking multiple medications
The effects of taste changes in later life are amplified in people who take multiple medications and in those who are chronically ill. This amplification effect may well be the consequence of salivary changes which are a common side effect of medication use. Interestingly tastants (the molecules sensed by taste) dissolve in the saliva to pass over taste buds to allow taste to be perceived. Hence changes in salivary flow will have an impact on ability to taste. Taste will also be changed in people who wear partial or complete dentures and in people with xerostomia (dryness in the mouth).
Surveys suggest that 10-24% of elderly people may experience significant loss of taste, with a higher prevalence noted in care homes. Yet our ability to eat and enjoy food and drink is inextricably linked to its taste, and the loss of taste in ageing can affect appetite, leading to reducing energy intakes and a greater risk of malnutrition. Impairment in the sense of smell also becomes more common, and smell is another important sense when it comes to appetite.
What can be done to help?
In terms of helping with taste changes, studies have shown that improving flavour of foods can improve nutritional intake and body weight in nursing-home patients. Ensuring good oral care and that fluid is available to help keep the mouth moist can help to enhance taste ability.
Perception of taste linked to age also can influence compliance to oral nutritional supplements (ONS) that are often prescribed to improve nutrient intake in service users at risk of malnutrition. Studies have found, for example, greater liking for milk-based, rather than for juice-based, products, while chilling is known to boost acceptability and palatability of ONS, so understanding whether the taste of supplements, as well as of meals and snacks is acceptable to service users may be helpful.
*All information is correct at the time of publishing