Walnut's heart benefit decoded

Scientists now know the additional ways the components of walnuts and their extracts lower risks of heart diseases.

Consumption of whole walnuts or their extracted oil can reduce cardiovascular risk through a mechanism other than simply lowering cholesterol, according to a team of Penn State, Tufts University and University of Pennsylvania researchers.

"We already know that eating walnuts in a heart-healthy diet can lower blood cholesterol levels," said Penny Kris-Etherton, distinguished professor of nutrition, Penn State.

"But, until now, we did not know what component of the walnut was providing this benefit. Now we understand additional ways in which whole walnuts and their oil components can improve heart health."

Results - which will appear in the June 1 issue of the Journal of Nutrition and are now online - showed that a one-time consumption of the oil component in walnuts favourably affected vascular health.

In addition, consumption of whole walnuts helped HDL - good cholesterol - perform more effectively in transporting and removing excess cholesterol from the body, reports Science Daily.

"Our study showed that the oil found in walnuts can maintain blood vessel function after a meal, which is very important given that blood vessel integrity is often compromised in individuals with cardiovascular disease," said Claire Berryman, graduate student in nutritional sciences, Penn State.

"The walnut oil was particularly good at preserving the function of endothelial cells, which play an important role in cardiovascular health," said Berryman.