A heart-healthy snack

Eating nuts and seeds frequently may reduce the risk of heart disease, a major review of a new study shows.

Nuts lower cholesterol levels and are linked to a lower risk of cardiovascular disease. Eating nuts lowers your risk of suffering or dying from a heart attack, shows a new systematic review and meta-analysis by researchers working at the University of Oslo and the Karolinska Institute in Stockholm and elsewhere. They came to this conclusion after examining the results of 60 previous studies. Their review was part of ongoing work on the development of new Nordic dietary guidelines.

“If you eat a handful of nuts every day, that’s about 30 grams, you will have a 20 to 25 percent lower risk of cardiovascular disease. In comparison, adults in the Nordic countries eat on average only about 4 grams of nuts per day. Many do not eat nuts or seeds,” says Erik Arnesen, a researcher at the University of Oslo and first author of the study.

A few nuts are better than nothing

Arnesen stresses that while scientists say “the more the merrier,” eating just a few nuts is better than none. Almonds, pistachios and walnuts appear to be the best at lowering cholesterol, but Arnesen says there’s no conclusive evidence yet to recommend specific types of nuts over others.

“Nuts have a beneficial effect on blood cholesterol levels, which is important to keep low to prevent the accumulation of fat in the arteries. This atherosclerosis, as it is called, is one of the biggest risk factors for attacks by heart,” he explains.

It is not known whether nuts affect the risk of stroke and type 2 diabetes

The researchers were also asked to investigate whether eating nuts also reduces the risk of stroke and type 2 diabetes.

“We’re not sure about that. Nuts don’t seem to affect blood pressure, which is one of the risk factors behind strokes. We also can’t be sure if nuts are good for blood sugar levels, which are linked to the risk of type 2 diabetes,” says Arnesen.

The results of the systematic review and meta-analysis were recently published in the journal Food and nutrition research.

Eating nuts can improve cholesterol levels in the population

When it comes to cardiovascular health, the bottom line is that eating nuts is beneficial.

“Although several studies have previously indicated this, this is the largest review to date on cardiovascular health,” says Arnesen.

“Thanks to this systematic review and meta-analysis, we can present a more accurate estimate of the true effects. Showing that nuts lower cholesterol levels provides a credible explanation for why there is a connection between eating nuts and the risk of disease cardiovascular”.

One of the reasons Arnesen gives for this connection is the fatty acid composition of nuts.

“Although nuts cannot be used to treat high cholesterol, we believe the effect is significant enough to be used as a preventive measure among the general population,” says the researcher.