Heart disease is the leading cause of death worldwide in both men and women, responsible for about 610,000 American deaths every year. For this reason, the recent finding published in the Journal of the American College of Cardiology1 is an important addition to the prevention discussion. Researchers have found that eating five or more servings of nuts per week correlates with a decreased risk of cardiovascular disease and coronary heart disease. Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels; coronary heart disease (CHD, alternately called coronary artery disease [CAD]) refers to the narrowing of the blood vessels that supply oxygen and blood to the heart muscle, and can cause angina, shortness of breath, or myocardial infarction (heart attack).
Nuts have long been known to be a healthy food. They are a good source of protein, fiber, magnesium, polyunsaturated fat, anti-oxidants, vitamin E and other bioactive compounds that are associated with decreased risk of both cardiovascular disease and cancer. Eating nuts more often has been associated with a lower risk of diabetes, colon cancer, gallstones and diverticulitis, as well as decreased cholesterol levels, inflammation and insulin resistance2. It’s estimated that in 2013, 4.4 million deaths were associated with a low daily nut intake3.
This new study examines the link between the frequency of eating nuts and the incidence of cardiovascular disease, while also looking at specific nuts and their impact on cardiovascular health.
For this study, researchers followed more than 210,000 people (participants of the Nurses’ Health Studies 1 & 2 and the Health Professionals Health Follow-Up Study) for 32 years, collecting medical and lifestyle information every two years, and food intake information every four years. From this population, 14,136 cases of cardiovascular disease (including coronary heart disease and stroke), were recorded. From combining the data on food intake and CVD, it was found that the more nuts participants ate, the lower their risk for developing cardiovascular and coronary heart disease.
Specifically, it was found that consuming a serving of walnuts two to three times every week was associated with a 19 percent decreased risk of developing cardiovascular disease, along with a 21 percent decrease in coronary heart disease risk. Peanuts (while not botanically a nut, are nutritionally similar and are thus included in these results) were linked with a 13 percent lower risk of cardiovascular disease and 15 percent reduced CHD risk, while tree nuts had a 15 percent lower cardiovascular risk and 23 percent CHD risk reduction. In total, five or more servings of nuts per week correlated with a 14 percent decrease in
cardiovascular disease and a 20 percent lower risk of coronary heart disease.
Stated limitations of this research are that study participants were restricted to health professionals (who may have a higher health literacy and healthier lifestyle than non-health professionals) and were mostly white. Additionally, the method of reporting health information and food intake (self-reported data) is always prone to errors. However, the researchers strongly believe the findings are generalizable to other ethnicities.
Dr. Emilio Ros, in his review of this study4, calls raw, unpeeled and generally unprocessed nuts “natural health capsules” that can improve health. And while this study did not specify how the nuts were prepared, simply looking at consumption of 28 grams of nut servings, for general health recommendations, salted, sweetened, candy-coated or chocolate-covered nuts are rarely what is referred to, and sticking to minimally processed is best. Nuts are a tasty addition to a menu, and can be easily incorporated into meals and snacks. What is considered a serving size of nuts? Twenty-three almonds; 14 walnut halves; 16 cashews; 6 Brazil nuts or 45 pistachios. They are great as toppings for a salad or grain pilaf and make a filling trail-mix-inspired snack combined with whole grain cereal or popcorn. Enjoy nut butter spread on toast, mixed into yogurt, or drizzled over fruit or vegetables. The variety of nut flavors allows them endless ways to be added into your daily menu, and the benefits for doing so are just as numerous.
- Gausch-Ferre, M., Liu, X., Malik, V.S., Sun, Q., Willet, W.C. et al (2017). Nut consumption and cardiovascular disease. Journal of the American College of Cardiology 70(20) 2519–2532
2. NA (2013). Nut consumption reduces risk of death. Accessed from Harvard Gazette
3. Aune, D., Keum, N., Giovannucci, E., Fadnes, L.T., Boffetta, P., et al. (2016). Nut consumption and risk of cardiovascular disease, total cancer, all-cause and cause-specific mortality: A systemic review and dose-response meta-analysis of prospective studies. BMC Medicine 14(207)
4. Ros, E. (2017). Eat nuts, live longer. Journal of the American College of Cardiology 70(20) 2533-2535
Bracha Kopstick is a Registered Dietitian in Toronto and owner of BeeKay Nutrition. She takes the “diet” out of dietitian, and wants you to take it out of your life! As a nutrition expert, Bracha promotes eating home-prepared foods more often and taking time to enjoy what you eat without any associated guilt. She is available for in-person and on-line counseling. Contact her at Bracha@beekaynutrition.com