The nuts seem to have the greatest benefit in low-income families who perhaps can't afford to buy the more expensive nuts that are often featured in health studies.
But a nut is a nut, say researchers from Vanderbilt University Medical Centre, and the peanut is as rich in nutrients and phyto-chemicals that are good for the heart as any other type of nut.
The researchers discovered the health-giving properties of the peanut when they examined the health records of 70,000 low-income Americans, and 130,000 Chinese men and women living in Shanghai.
Those eating the most peanuts every day enjoyed the greatest protective effect, not surprisingly. Those eating the most were up to 38 per cent less likely to die from heart disease and 21 per cent less likely to die prematurely from any disease.
The amounts eaten varied, but researchers reckon that eating one serving of 1.5 ounces of whole nuts-equivalent to a small handful-each day should give you all the protection you need.
(Source: JAMA Internal Medicine, 2015; doi: 10.1001/jamainternmed.2014.8347)