According to a new study, a diet rich in walnuts could help reduce bad cholesterol and lower the risk of cardiovascular disease. Low-density lipoprotein (LDL) or bad cholesterol was found to be lowered in people who consumed about ½ cup of walnuts every day for two years.
The study, published in the American Heart Association journal Circulation, was a sub-study of the Walnuts and Healthy Aging study, which examined whether walnuts contributed to healthy aging.
Walnuts are known to be a rich source of omega-3 fatty acids (alpha-linolenic acid), which have previously 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 Emilio Ros, M.D., Ph.D.,
“LDL particles come in various sizes. Research has shown that small, dense LDL particles are more often associated with atherosclerosis, the plaque or fatty deposits that build up in the arteries. Our study goes beyond LDL cholesterol levels to get a complete picture of all of the lipoproteins and the impact of eating walnuts daily on their potential to improve cardiovascular risk.”
The study was conducted from 2012 to 2016 and involved 708 participants between the ages of 63 and 79 who were healthy, independent adults who live in Barcelona, Spain, and Loma Linda, California.
All participants were randomly divided into two groups. The first group was the active intervention group, which added about half a cup of walnuts to their usual daily diet. The second group, the control, did not eat any walnuts.
After two years, all participants’ cholesterol levels were tested, and the concentration and size of lipoproteins were analyzed using nuclear magnetic resonance spectroscopy. This type of advanced testing allows physicians to more accurately identify lipoprotein features known to cause a risk of cardiovascular disease.
At the study conclusion, it was found that participants in the walnut group had lower LDL cholesterol by an average of 4.3 mg/dL, and total cholesterol was lowered by an average of 8.5 mg/dl. Daily consumption of walnuts reduced the number of total LDL particles, which are associated with a lower risk of cardiovascular disease.
Intermediate Density Lipoprotein (IDL) cholesterol also decreased. This type of cholesterol is a precursor to LDL and is a relevant risk factor for cardiovascular disease independent of LDL.
Researchers noted that at the start of the study, all participants were healthy. However, as it was an elderly population, close to 50% of participants were being treated for both high blood pressure and hypercholesterolemia. Many of the participants had average cholesterol levels thanks in part to statin treatment.
Eating a handful of walnuts every day is a simple way to take care of your cardiovascular health. According to the American Heart Association, walnuts are high in omega-3 fatty acids and are appropriate even for individuals who are worried about unwanted weight gain.