Peanuts may protect the arteries and help prevent heart attacks and strokes, new research suggests.

Eating three ounces of peanuts with a high fat meal maintained blood vessel elasticity in overweight and obese but otherwise healthy men, US scientists found.

The nuts suppressed levels of triglycerides, a harmful type of blood fat linked to artery stiffness.

This in turn helped to ensure arteries stayed open and improved blood flow, thereby reducing the risk of cardiovascular events such as heart attacks and strokes.

Nutrition expert and lead researcher Professor Penny Kris-Etherton, from Pennsylvania State University, said: "Typically, whenever we eat something, it causes the arteries to get a little bit stiffer during the post-meal period, but we have shown that if you eat peanuts with your meal, this can help prevent the stiffening response.

"After a meal, triglycerides increase and this typically decreases the dilation of the arteries, but the peanuts prevent that big increase in triglycerides after the meal.

"And that may be the mechanism behind this effect, because the triglycerides are not getting so high, which may explain why there is not a decrease in artery elasticity."

A total of 15 healthy overweight and obese men took part in the study, reported in the Journal Of Nutrition.

One group was given a high fat meal accompanied by three ounces of ground unsalted peanuts in the form of a shake.

Another had the same meal and a shake not containing peanuts.

Blood samples were taken to test levels of blood fats and insulin while ultrasound recordings measured the flow through arteries.

The results showed a 32% reduction in triglyceride blood levels after consuming peanuts.

Three ounces of peanuts is about three times an average serving size, the researchers pointed out.

They said that eating whole peanuts instead of grinding them up into a shake would probably produce the same response.