LONDON —  Aspirin is generally known to be useful in preventing heart attacks and strokes, but now researchers believe the humble aspirin could also hold the key to warding off dementia and cancer.

The claim has been made at the launch of the largest ever study into the health benefits of the everyday medicine, which has long been thought of as a health-booster.

A study of 15,000 people aged over 70 will be the most extensive clinical trial on the use of aspirin to prevent disease in the elderly, Daily Mail reported.

Research team leader Mark Nelson, from Hobart’s Menzies Research Institute in Tasmania, Australia, said.

"Remember aspirin is an over-the-counter medication; you don’t need a doctor to prescribe it, you don’t need a doctor to tell you you’ve turned 70.

So this is something that can be done very simply, very cheaply if we find that it’s an effective strategy."

Nelson said the study starts next summer and results are expected in 2018.

Millions of people who take the pill to fight heart disease or the risk of a stroke benefit from its effectiveness at thinning the blood and how it helps to prevent clotting.

It cuts the danger of further heart attacks or strokes by at least 23 per cent.

Research has shown regular users have a lower risk of developing Alzheimer’s disease, the main form of dementia.

Scientists believe its protective effect may be due to its anti-clotting action helping blood flow to the brain.

Research has also shown that aspirin may have a role in fighting cancer, particularly gastro-intestinal cancers.

"Now that makes sense because you take it orally so in aspirin you’ve got that natural component."

In the study  in the journal Contemporary Clinical Trials  the team wants to establish whether the benefits of a low dose of aspirin outweigh the risks linked to its use.