Move over energy bars and sports supplements - a new contender for the perfect health club snack has come to light: the humble peanut.

Eating peanuts and peanut butter five days a week may halve the risk of a heart attack, according to research published in the Journal of Nutrition.

A team from Harvard Medical School studied 6,000 women with Type 2 diabetes - the condition associated with obesity, lack of physical activity and poor diet that can increase the risk of heart attacks and strokes.

Those who frequently ate peanuts or peanut butter were found to have the greatest protection against heart attack, with the risk reduced by up to 44 per cent.

It's believed that the nuts help lower bad cholesterol and reduce inflammation in the body, as well as boosting blood vessels around the heart.