People who regularly eat nuts may reduce their risk of dying from heart attacks or stroke, a new study suggests.

According to the findings, eating nuts at least twice a week is linked with a 17% reduced risk of cardiovascular mortality. Cardiovascular disease includes all diseases of the heart and circulatory system, including stroke and coronary artery disease, which can lead to angina and heart attacks.

Researchers in Iran looked at the link between nut consumption and the risk of cardiovascular disease and death in almost 5,500 adults aged over 35.

The participants had no history of cardiovascular disease at the start of the study and they came from both rural and urban areas. Between 2001 and 2013, their intake of nuts, such as almonds, walnuts and pistachios, was assessed, and cardiovascular events were monitored.

Specific events investigated were coronary heart disease, stroke, total cardiovascular disease, death from cardiovascular disease and death from any cause.

The researchers found that during the 12-year follow-up period, those who ate nuts twice a week had a 17% reduced risk of dying as a result of cardiovascular disease compared to those who ate nuts only once every two weeks.

They said that the results stood even when other factors that could have affected the results were taken into account, such as age, smoking and physical activity.

Current guidelines from the European Society of Cardiology (ESC) state that a healthy diet should contain no more than 30g of unsalted nuts per day. This is around 20 almonds, 10 walnuts, 15 cashews or 60 pistachios.

"Raw fresh nuts are the healthiest. Nuts should be fresh because unsaturated fats can become oxidised in stale nuts, making them harmful. You can tell if nuts are rancid by their paint-like smell and bitter or sour taste," explained the study's author, Dr Noushin Mohammadifard, of the Isfahan Cardiovascular Research Institute in Iran.

Details of these findings were presented at the ESC Congress 2019 together with the World Congress of Cardiology in Paris, France.