Walnuts have long been praised for their health benefits, with the nut known for being rich in protein and several dietary minerals.
Now, researchers have found that a diet that includes walnuts may contribute to longevity.
As part of a two-year randomised, controlled trial examining whether walnuts contribute to healthy ageing, experts evaluated if regular walnut consumption, regardless of a person's diet or where they live, has beneficial effects on lipoproteins.
Accordingly, they reported that healthy older adults who ate a handful of walnuts (about half a cup) a day for two years "modestly lowered" their level of low-density lipoprotein or LDL cholesterol levels. Consuming walnuts daily also reduced the number of LDL particles - a predictor of cardiovascular disease risk.
Walnuts are a rich source of omega-3 fatty acids, which have been shown to have a beneficial effect on cardiovascular health.
"Prior studies have shown that nuts in general, and walnuts in particular, are associated with lower rates of heart disease and stroke. One of the reasons is that they lower LDL-cholesterol levels, and now we have another reason: they improve the quality of LDL particles," said study co-author Dr. Emilio Ros. "Eating a handful of walnuts every day is a simple way to promote cardiovascular health. Many people are worried about unwanted weight gain when they include nuts in their diet. Our study found that the healthy fats in walnuts did not cause participants to gain weight."
According to the American Heart Association officials, walnuts are especially high in omega-3 fatty acids, the same heart-healthy fat found in oily fish. A serving size is a small handful or 1.5 ounces of whole nuts or two tablespoons of nut butter.
Full study results have been published in the journal Circulation.