Eating walnuts daily may help lower ‘bad’ cholesterol, according to a recent study.
Walnut and other nut consumption has already been associated with lower rates of heart disease and stroke, but this research adds to evidence by showing they lower lipoprotein (LDL) cholesterol as well as reduce the likelihood LDL particles will form plaques on artery walls.
Heart attacks and strokes are caused by blockages in the arteries because of these plaques.
Study co-author Emilio Ros says daily walnut consumption reduces the number of small LDL particles.
“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,” Dr Ros explains.
The research, published in Circulation, looked at the cholesterol levels and concentration and size of lipoproteins in 628 63-to 79-year-olds, half of whom had been eating ½ a cup of walnuts daily for two years.
Heart-endangering LDL and IDL cholesterol lowered
The researchers found a modest decrease in LDL and Intermediate Density Lipoprotein (IDL) cholesterol levels in the walnut eating group. IDL cholesterol is also a lipid cardiovascular risk factor.
They also observed the walnut eaters had a 4.3 per cent reduction in LDL particles and a 6.1 per cent reduction in the number of small LDL particles.
While the reductions weren’t huge, Dr Ros says the participants had fairly controlled cholesterol levels and suggests bigger reductions may be observed in people who have higher cholesterol levels.
“Eating a handful of walnuts every day is a simple way to promote cardiovascular health,” he says.
While nuts can be high in energy, the researchers found the participants did not gain weight from eating that number of walnuts every day.
The research was funded by the California Walnut Commission, but this was openly acknowledged. Also, the participants and researchers knew who was and who wasn’t eating the walnuts, meaning it wasn’t the gold standard randomised double-blind study method that provides the strongest evidence of causation.
Why walnuts are good for you and how to eat more
Walnuts are an excellent source of heart-and brain-friendly omega-3 fats and their consumption has been associated with lowered colorectal cancer risk.
It’s easy to include a handful of walnuts in your day. Try using them instead of pine nuts in pesto, add them to your muesli or toast and toss them into a stir-fry.
6 delicious walnut recipes to try
Article sources and references
- Sujatha Rajaram, Montserrat Cofán, Aleix Sala-Vila, Ella Haddad, Mercè Serra-Mir, Edward Bitok, Irene Roth, Tania M. Freitas-Simoes, Amandeep Kaur, Cinta Valls-Pedret, Mónica Doménech, Keiji Oda, Dolores Corella, Joan Sabaté, Emilio Ros. Effects of Walnut Consumption for 2 Years on Lipoprotein Subclasses Among Healthy Elders: Findings From the WAHA Randomized Controlled Trial. Circulation, 2021; DOI: 10.1161/CIRCULATIONAHA.121.054051https://www.ahajournals.org/doi/pdf/10.1161/CIRCULATIONAHA.121.054051
- American Heart Association. "Eating walnuts daily lowered 'bad' cholesterol and may reduce cardiovascular disease risk." ScienceDaily. ScienceDaily, 30 August 2021.https://www.sciencedaily.com/releases/2021/08/210830081805.htm