Older Aussies urged to drink more water

Elderly people face a greater risk of becoming dehydrated because their brains switch off the thirst sensation before they are properly rehydrated, according to research by scientists in both Melbourne and Texas.

The Howard Florey Institute combined with the University of Texas in a study which demonstrated that the most likely reason for older people to drink less water was that there was a brain malfunction involving the thirst sensation.

The discovery was made after the injection of saline into two groups of men – young and old – and comparing their responses to thirst. Scans of brain activity showed that an area of the brain associated with thirst was turned off in the elderly after they drank small amounts of water.

Commenting on the study, Australian Medical Association Victoria vice-president and geriatrician Dr Mark Yates, said it was essential for older people to drink more water, especially in hot summer weather.