Walnuts: A well-studied ingredient that improves basic health and helps reduce risk of disease.
By Lisa Parrish, GMC Editor
Consuming healthy, nutrient-dense foods is a foundation for good health. That much is understood. What becomes murky is how much to consume and what health benefits can actually be achieved when eating the ingredient over time?
I spoke with Carol Berg Sloan, RDN, health research director with the California Walnut Commission, and discussed the curative and restorative health benefits of a commonly used and widely available ingredient: walnuts. We discussed how this one tree nut has been extensively studied for more than 30 years and the medicinal properties are validated through research study after study. She also touched on how the nutritional content and health benefits are changed with heat. (Spoiler alert: they are just as beneficial baked as they are raw.)
What are the medicinal properties of walnuts?
According to Berg Sloan, research has found that walnuts are a factor in decreasing the risk of heart disease. Several studies looked at biomarkers for heart disease and found walnuts help lower HDL (bad) cholesterol levels and they have a positive impact on reducing plaque in the arteries.
She also said walnuts and cruciferous vegetables help reduce the likelihood of cancer. Walnuts may also delay cognitive declines in younger populations. Berg Sloan noted that walnuts need to be a part of an overall healthy diet.
What is a unique nutritional characteristic of walnuts?
Walnuts are high in alpha-linolenic acid (ALA), the plant-based omega-3 fatty acid. “Omega-3 fatty acid is essential to have,” she said. “And the body does not produce it, so you have to eat it.” There are three main types of omega-3 fatty acids, ALA, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Both EPA and DHA are commonly found in fish and shellfish.
Berg Sloan suggested, “You need all three fatty acids. So, a chef might make a walnut-crusted fish and you would get all three in one dish.”
How much and how often does one have to consume walnuts to derive their health benefits?
Research supports that between one- and two-ounces a day has a positive impact on the body. There exists a disparity between government bodies on this point, with the USDA listing a serving as one-ounce while the FDA says it should be 1.5-ounces. In practical terms, Berg Sloan suggests eating half of a handful a day will provide all the plant-based omega-3 fatty acid the body requires.
“Health benefits come from eating walnuts frequently over time. That is important,” she said. She also noted that eating less fat and consuming lean proteins as part of an overall healthy diet is extremely beneficial to good health. And, although she was not aware of any detrimental effects of eating more than a serving a day of walnuts, she said that eating too much of any one food is not good for the body, whether that is butter, pork or even walnuts.
Walnuts are softer than other tree nuts which make consuming them raw more palatable. Also, the California Walnut Commission recommends toasting walnuts at 350 degrees for eight minutes to intensify the flavor. This toasting does not impact walnut’s nutritional benefits.