A study has stated that mental decline or dementia can be warded of by walking.

More brain tissue was seen in people who walked six to nine miles in a week, as stated by brain scans.

Brain shrinkage that is linked to memory problems was also seen lesser in people who walked, the Pittsburgh University study suggests.

Signs of cognitive impairment or even dementia were checked among volunteers, who had an average age of 78.

Access to brain scan results from four years previously which measured the amount of grey matter in their brains was with the Pittsburgh team.

As people grow older, this diminishes and it is found at various parts of the brain.

Questions about the number of city blocks they walked were asked to people in their 60s.

A greater volume of grey matter was seen in people who walked at least 72 blocks or six to nine miles a week.

A measurable cognitive impairment and dementia in some cases was found after four years after the scans in 40 per cent of the group.

People who walked more had 50 per cent chances of having such problems.