Why We Love Nuts

Besides peanut butter (which isn’t even a nut, it’s a legume!), nuts do not feature prominently in the American diet. Only 6% of Americans report eating nuts on any given day (1). Why?

Nuts, the seed within the hard ovary walls of fruit, have been part of the human diet since prehistoric times (2). From the 1970s through the 1990s, foods high in fat were targeted for contributing to rising rates of chronic diseases. Nuts were lumped in with other food sources of fat as Americans looked to replace fat in their diets with carbohydrates (2). Over time, we learned that evidence does not support a link between eating nuts and gaining weight (3, 4, 5). In fact, people who eat nuts regularly are leaner than others (1). In addition, nuts have been shown to decrease the risk of heart disease (2).

Nuts are a nutritious food packed with unsaturated fat, fiber, protein, vitamins, minerals and phytochemicals. Walnuts are also a source of omega-3 fatty acids. The nutrient profile depends on the nut, but many nuts are sources of vitamins E and K, folate, magnesium, copper and potassium (1, 3). Nuts have some of the highest antioxidant capacity among all foods (2).

Regular nut intake is associated with a reduced risk of heart disease through actions on blood sugar, blood lipids, weight, blood pressure and antioxidant and anti-inflammatory effects (6, 7). Nuts can help lower total and LDL cholesterol while maintaining HDL cholesterol, an important strategy for reducing the risk of heart disease (6, 8). It is recommended to eat 1 1/2 ounces of nuts daily to protect heart health (1, 6).

Given the positive health benefits of eating a nutrient-dense food like nuts, not nearly enough Americans are incorporating them into their daily meals and snacks. Nuts can play an important role in the diet in many ways:

●     Nuts are key ingredients in the Mediterranean Diet, a way of eating that incorporates all foods but emphasizes plant foods and guides decisions about how often we should be eating certain foods (2).

●      Nuts may replace other snacks that are not as nutritious. An appropriate portion of nuts with a piece of fruit or veggie sticks is a delicious and balanced snack (1).

●      Because nuts have protein and fiber, they promote satiety and fullness in between meals and snacks. Eating foods with protein and fiber may influence how many calories are consumed during later eating occasions (3).

●      Because of their nutrient profile, nuts may also affect our blood sugar response (2).

●      It is currently being studied whether all of the calories in nuts are absorbed (3).

●      If nut allergies are a concern, opt for seeds, which have a similar nutrient profile.

Changes to what we eat, as well as other lifestyle strategies, should be the first approach to reducing the risk of chronic diseases like heart disease (9). When nuts are incorporated into meals and snacks, the quality of our diet improves (2, 5). However, our entire diet matters. Choose nuts as part of an overall way of eating that is heart healthy.

References

(1) Brown RC et al. Perceptions and Knowledge of Nuts amongst Health Professionals in New Zealand. Nutrients 2017;9:220.

(2) Hernández-Alonso P et al. Nuts and Dried Fruits: An Update of Their Beneficial Effects on Type 2 Diabetes. Nutrients 2017;9:673.

(3) Carughi A et al. Pairing nuts and dried fruit for cardiometabolic health. Nutrition Journal 2016;15:23.

(4) Mattes RD and Dreher ML. Nuts and healthy body weight maintenance mechanisms. Asia Pac J Clin Nutr 2010;19(1):137-141.

(5) de Souza RGM et al. Nuts and Human Health Outcomes: A Systematic Review. Nutrients 2017;9:1311.

(6) Kim Y, Keogh J and Clifton PM. Nuts and Cardio-Metabolic Disease: A Review of Meta-Analyses. Nutrients 2018;10:1935.

(7) Morgillo S, Hill AM and Coates AM. The Effects of Nut Consumption on Vascular Function. Nutrients 2019;11:116.

(8) Kalita S et al. Almonds and Cardiovascular Health: A Review. Nutrients 2018;10:468.

(9) McKay DL et al. A Pecan-Rich Diet Improves Cardiometabolic Risk Factors in Overweight and Obese Adults: A Randomized Controlled Trial. Nutrients 2018;10:339.