A study by Harvard Medical School suggests that eating peanuts or peanut butter at least five days a week can nearly halve the risk of a heart attack.

Peanuts appear to lower bad cholesterol, reduce inflammation in the body and boost the health of blood vessels around the heart.

Researchers at Harvard Medical School analysed the diets of more than 6,000 women who had type 2 diabetes, which can increase the risk of heart attack and stroke.

They found that those regularly eating peanuts had the greatest protection against heart attack and stroke. A report published in the Journal of Nutrition, claimed the risk was reduced by up to 44pc.

“Consumption of at least five servings a week of one ounce of nuts or one tablespoon of peanut butter was significantly associated with a lower risk of cardiovascular disease.”

In Britain, it’s well known that poor diet and lifestyle has led to a surge in cases of type 2 diabetes, from 1.5 million five years ago to 2.2 5million now.

Ellen Mason of the British Heart Foundation said, “It is beneficial to include nuts in our diets as they are low in the saturated fats that raise our cholesterol. However peanut products can be full of added sugar or salt so check the label first. Also don’t forget that nuts are high in overall calories. Eating more of one food in isolation will not make a dramatic difference to your health if you are inactive and don’t have a balanced diet.”

Of course, peanuts are not really nuts but part of the legume family, which includes peas and beans. But it seems they have similar properties to nuts in general.

It would be interesting to compare these findings with results from other types of nut.

In a counter-intuitive article in the New York Times, which quotes researchers in Germany and Boston, exercise and antioxidants don’t mix. “If you exercise to improve your metabolism and prevent diabetes, you may want to avoid antioxidants like vitamins C and E.”

Dr. Michael Ristow, a nutritionist at the University of Jena in Germany, said, “If you exercise to promote health, you shouldn’t take large amounts of antioxidants. … antioxidants in general cause certain effects that inhibit otherwise positive effects of exercise, dieting and other interventions.”

It seems that exercise encourages muscle cells to metabolize glucose by combining carbon atoms with oxygen. In the process, highly reactive oxygen molecules are released which then attack various parts of the body damaging the tissues.

The Jena team found that in the group taking antioxidant vitamins, like vitamins C and E, there was no improvement in insulin sensitivity and almost no activation of the body’s natural defence mechanism against oxidative damage.

Once again, what we thought was done and dusted has been called into question by more research.

However, the advice does not apply to fruits and vegetables, Ristow said, even though they are high in antioxidants, it may be that other substances they contain outweigh any negative effect.

Andrew Shao of the Council for Responsible Nutrition, a trade association of dietary supplement makers, said, “I wouldn’t change recommendations for anyone based on one study. This is one small piece of the puzzle.”

The amount of oxidative damage increases with age, and according to one theory of aging it is a major cause of the body’s decline.

The findings appear in this week’s issue of The Proceedings of the National Academy of Sciences.

John Evans

There are a lot of articles around about the causes of type-2 (late onset) diabetes.

Missing the obvious fact it’s almost always about the balance between diet and exercise, a variety of factors are adduced for this tiresome disease.

Did you know that both lack of and too much sleep can tip you over the edge? Either option can make you far more likely to develop diabetes, according to researchers at the Universite Laval in Quebec, Canada. The results are published in the journal, Sleep Medicine.

Optimum sleeping times are seven to eight hours a night, they say. If you undershoot or exceed that, you are two and a half times more likely to suffer blood sugar abnormalities.

Researcher Angelo Tremblay says, “The risk remains significant even after a statistical adjustment for body mass index and waist circumference. … It is clear the recommendation to seek an optimal sleep duration seems to be appropriate, but for some individuals it is easier to say than do.”

One factor that isn’t mentioned is the differences between individuals. Such research often assumes that everyone’s reaction to stress is identical. It isn’t.