The researchers think they now hold the key to determining why over-80s are so prone to losing weight, often very qucikly.
Elderly people produce a greater amount of peptide YY, the hormone that tells humans when they’re full, the study found.
The team, from Plymouth University, hope the study will help health professionals ensure elderly people follow the right diet to ensure they are eating enough and prevent loss of appetite which can lead to a range of illnesses and even death.
Study leader Mary Hickson, professor of dietetics at the university, said: “With ageing there is frequently a loss of appetite, termed anorexia of ageing, which can result in under-nutrition. We do not know how appetite control alters with ageing, so this study was a necessary and promising start.”
The study saw studied women over the age of 80 eat a breakfast after several hours of fasting. Their hormone levels were compared to those of a number of healthy younger participants in three age brackets which were 20–39, 40–59 and 60–79.
Each participant had their levels of peptide YY measured at regular intervals for three hours alongside their levels of ghrelin – the hormone that tells us when we are hungry.
Researchers had previously suggested weight loss in the over-80s could be down to lower production of ghrelin, resulting in older people feeling less hungry.
But the latest results showed each of the over-80s tested produced a greater amount of PYY than their younger counterparts, while their ghrelin levels did not change.
Prof Hickson said she now hoped to work to investigate the hormone imbalance “to address, and hopefully combat, anorexia of ageing” in the elderly.
Anorexia of aging and consequent weight loss is common among the elderly, especially in nursing home residents and in hospitalised older patients. It is hoped this stury will help other researchers and health care professionals such as GPs and dieticians look at ways to decrease loss of appetite