Are you Nutty if You Eat Nuts?
A common nutrition question we get at The Cooper Institute is “Are nuts good or bad for you?” Many years ago when low fat diets were popular, and before we or anyone else knew any better, people were advised to limit their intake of nuts because of their high fat content. My, how times have changed! Rather than being the villain of yesteryear, fat is now acknowledged as an important component of a healthful diet. Before I go any further, it’s important to realize that not all dietary fats are alike. While monounsaturated and polyunsaturated fats are regarded as healthful, individuals both young and old are still advised to limit their intake of saturated and trans fats.
So what about nuts? First off, nuts are a great source of protein, fiber, vitamins, minerals, and antioxidants. While they do have a high fat and calorie content, nuts are loaded with heart-healthy mono and polyunsaturated fat, and most nuts are relatively low in saturated fat. The key thing to remember is moderation. No one is saying that it’s good to consume an endless amount of nuts or peanut butter every day. On the other hand, there is strong scientific evidence that consuming an ounce (a small handful) of nuts daily is associated with a marked reduction in the risk of chronic disease or early death. Let’s take a look at a couple of recent state-of-the art studies.
In a 2015 paper published in the American Journal of Clinical Nutrition, 20742 male physicians with an average age of 67 years completed a comprehensive food-frequency questionnaire between 1999 and 2002. The group was followed for an average of 9.6 years, during which 2732 all-cause deaths occurred. The relationship between nut consumption and risk of death was evaluated after taking several other factors that might ‘muddy the waters’ into account. Results are shown in Figure 1.
As shown in the Figure, there was a decreased risk of all-cause mortality across increased nut consumption category, with the group consuming 5 or more servings per week enjoying a 26% lower risk of death during the study period as compared to the group who never consumed nuts.
In another manuscript published in 2016, researchers combined 20 published studies to examine the relationship between nut consumption and risk of all-cause mortality, cardiovascular disease and cancer, as well as diabetes and other causes of mortality. Using no intake of nuts as the reference group, for every 1 ounce increase in daily nut intake there was a 21% and 15% reduction in risk of cardiovascular disease and cancer, respectively. All-cause and diabetes mortality was reduced by 22% and 39% per 1 ounce increase in daily nut intake, respectively.
Want more NUTrition information? Here’s a link to a document that provides the nutrients in one ounce of many types of nuts. Want more information on what one ounce of nuts really looks like? Here’s a great graphic. By the way, 2 tablespoons of peanut butter are equivalent to a 1 ounce serving of nuts.
An extremely important thing to mention is that if you are planning to increase your nut intake, be sure to cut back in other areas, especially if you are watching your waistline. A great place to start cutting back is on so-called ‘empty calories.’ These would include foods and beverages with a lot of added sugars (e.g., soda), as well as foods that contain a lot of highly refined carbohydrate (e.g., doughnuts) and saturated fat (e.g., whole milk dairy). If you choose to drink, go easy on the alcohol as well!
Hshieh, T., Petrone, A., Gaziano, J., Djousse, L. (2015). Nut consumption and risk of mortality in the Physicians’ Health Study. Am J Clin Nutr, 101(2):407-412. DOI: 10.3945/ajcn.114.099846
Aune, D., Keum, N., Giovannucci, E., Fadnes, L., Boffetta, P., Greenwood, D….Norat, T. (2016). Nut consumption and risk of cardiovascular disease, total cancer, all-cause and cause-specific mortality:a systematic review and dose-response meta-analysis of prospective studies. BMC Med, 14(1):207. DOI: 10.1186/s12916-016-0730-3