Beans for Health of Self and Planet

By Jennifer Bean, MS, RDN/LD

Two new studies further reveal the surprising power of beans to boost personal health and promote environmental sustainability.

Beans are rich in both macronutrients and micronutrients. Macronutrients, which provide us with energy or calories, include carbohydrates, proteins, and fats. Beans contain carbohydrates (as complex carbohydrates like fiber), protein (the only nitrogen-containing macronutrient) and a small amount of fat. Beans also contain micronutrients, or vitamins and minerals, such as vitamin C and potassium, zinc, iron, and B-vitamins, like folate, among others.

When we categorize beans by how they are consumed culinarily, beans are in the vegetable group even though they have more protein than any other food in that group. The 2020-2025 Dietary Guidelines for Americans recommend that people over the age of 2 consume beans weekly1. However, the optimal “dose” — meaning the ideal serving size and frequency — needed to positively affect both human health and environmental sustainability is still unclear. Two groups of researchers published review papers earlier this year examining just that question — how much bean consumption is optimal for health and sustainability?

In a paper published in the journal Nutrients, Naisi Zhou and colleagues reviewed thousands of studies to rigorously examine the health effects of regular bean consumption. They report on observational studies that monitored people’s diets and health outcomes, as well as interventional studies that altered diets and measured health indicators like blood pressure, cholesterol, and glucose levels. Observational studies found that individuals consuming one to two one-cup servings of beans daily had lower rates of type 2 diabetes, cancer, cardiovascular events (such as stroke and heart attack) and overall mortality. The intervention studies looked at endpoints like blood cholesterol or fasting glucose. These studies controlled how beans were included in people’s diets, specifically by either substituting beans for red meat or simply adding beans to the person’s usual food intake. The strongest effects occurred when beans were substituted for red meat, resulting in improvements in short-term inflammatory markers (like C-reactive protein), measures of cholesterol (like LDL and HDL cholesterol) and blood sugar control (like hemoglobin A1c).

Importantly, while the effects were not as strong, simply adding beans into a person’s regular diet still showed similar positive effects. The researchers noted there was not enough evidence to look at a dose response, meaning exactly how much beans people should consume to decrease their risk for cardiovascular disease, type 2 diabetes or cancer, or exactly how beans exerted their health protection effects2.

Several unique characteristics of beans also provide health benefits to the planet. A second review article from a working group in Europe reported on the environmental benefits of regularly including beans on the plate. Beans work with nitrogen-fixing bacteria in the soil to remove nitrogen oxide, the third strongest greenhouse gas, from the air. This relationship enriches the soil with fertilizing nitrogen, which improves crop yields and reduces the need for additional fertilizer when rotating crops. Nitrogen fixation contributes to the higher protein content of beans compared to other vegetables, as protein is a way for these plants to store nitrogen. The resources required to cultivate beans as a protein source, such as water and land, are much less than those needed for other protein sources, such as meat and dairy. Similarly, the inputs required to process beans, both commercially and at home, are lower than those of other protein sources. Much like the first review article, the authors note that we still need to know the quantity of beans to consume to ensure optimal human health and sustainability3.

So, what can you do today to use beans to promote your own health as well as the health of the planet? Two well-researched eating plans that incorporate beans align with these findings. The DASH diet, originally developed to manage high blood pressure, recommends four to five half-cup servings of beans weekly for overall health4. The Therapeutic Lifestyle Changes, or TLC, diet, aimed at lowering cholesterol, suggests three to five servings of vegetables, including beans, per day5. Similarly, the 2020- 2025 dietary guidelines for Americans include beans in the vegetable group as party of a healthy eating plan1. These plans offer practical ways to include beans in your diet, promoting both personal health and environmental sustainability.

Jennifer Bean, MS, RDN/LD, is a professor in the Division of Food, Nutrition & Exercise Sciences at the University of Missouri.

  1. US Department of Agriculture. Dietary Guidelines for Americans, 2020-2025 [Internet]. Dietary Guidelines for Americans, 2020-2025. 2020. Available from: ↩︎
  2. Zhao N, Jiao K, Chiu Y-H, Wallace TC. Pulse Consumption and Health Outcomes: A Scoping Review. Nutrients 2024;16:1435. ↩︎
  3. Lisciani S, Marconi S, Le Donne C, Camilli E, Aguzzi A, Gabrielli P, Gambelli L, Kunert K, Marais D, Vorster BJ, et al. Legumes and common beans in sustainable diets: nutritional quality, environmental benefits, spread and use in food preparations. Front Nutr 2024;11:1385232. ↩︎
  4. National Institutes of Health, National Heart, Lung, and Blood Institute. DASH Eating Plan [Internet]. DASH Eating Plan. 2021. Available from: ↩︎
  5. National Institutes of Health, National Heart, Lung, and Blood Institute. Therapeutic Lifestyle Changes (TLC) To Lower Cholesterol [Internet]. Therapeutic Lifestyle Changes (TLC) To Lower Cholesterol. 2024. Available from: ↩︎

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