London: Danish researchers have found that signs of brain ageing, which manifests itself in forms such as Alzheimer's and Parkinson's disease, could be postponed if placed on a high-fat diet.

"Our study suggests that a high-fat diet can postpone ageing processes. The findings potentially imply that patients with Alzheimer's and Parkinson's disease in the long term may benefit from the new knowledge," said professor Vilhelm Bohr from the Centre for Healthy Aging at the University of Copenhagen and the National Institute of Health.

Throughout our lives, the cells have a system that repairs the DNA damage that occurs all the time.

Humans age when the repair system ceases to function. A defect in the DNA repair system causes the disorder Cockayne syndrome, where patients prematurely age as children and die at an age of 10-12 years.

In the new study, researchers saw a particular positive effect when mice were given medium chain fatty acids from coconut oil.

The results showed that placing a mouse model of Cockayne syndrome on a high-fat diet postponed the ageing processes such as impaired hearing and weight loss.

Our brain has a constant need for fuel in the form of either sugar or ketones - the brain's fuel reserve.

The body breaks down fat if it needs sugar and during this process, it produces ketones, researchers concluded.

The study was published in the scientific journal Cell Metabolism.