Turns out…a hill of beans is worth quite a lot!

Members of the Fabaceae family, beans are leguminous plants with a rich history.¹ In fact, beans have been cultivated for nearly 6,000 years in North and South America,¹ but they are considered a worldwide dietary staple. In the United States, the most common types of beans that are planted and consumed include black, pinto, navy, kidney, and fava.² Garbanzo (chickpeas), cannellini, Lima, Great Northern, and mung are other examples of beans. A summer crop that thrives in warm temperatures, beans are very nutrient-dense, meaning they are both high in nutrients and low in calories.² Indeed, beans are an unstoppable dietary force that provide the body with fiber and many culinary dishes with a protein base. 

Beans Provide Protein and Fiber

Notwithstanding slight variations in nutrition, all varieties of beans generally provide similar nutrients and health benefits.^2–4 For starters, beans are high in protein and fiber. 

Protein is integral for the health, enzyme activity, and function of every cell in the body, as well as offering structural support for these cells, too.^1–4 Soybeans, in particular, are considered a complete protein, as they harbor all nine of the essential amino acids the body needs to carry out the above functions.⁵ And, according to researchers, individuals who consume higher amounts of soy protein (tofu or edamame), compared to animal protein (i.e., meat, eggs), significantly reduce their risk of prostate and breast cancer.⁵ Finally, for those who only consume plant-based foods, beans are considered a complete source of protein.⁵

In terms of fiber content, beans are an excellent source of both soluble and insoluble fiber. Typically, a half cup of beans contains seven or more grams of total dietary fiber.⁶ Dietary fiber aids digestion by slowing the process, allowing the digestive track to effectively break down nutrients for the body, while feeding the probiotics that comprise our gut microbiome. The slowing of digestion also moderates blood-sugar levels, which helps prevent “crashes” in energy.⁶ Since  beans are low on the glycemic index (low sugar content) and assist in regulating blood sugar levels, many healthcare professionals and the American Diabetes Association encourage individuals with diabetes to consume soaked or cooked low-sodium beans daily.⁷

Beans Have Anti-inflammatory effects

 The fiber in beans can also help keep inflammatory responses at bay.^8,9 Lower levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), pro-inflammatory immunity cells (cytokines) that signal immune/inflammation responses, have been reported in those who maintain a high intake of fiber.⁸ Reducing inflammation reduces risks of developing many chronic health disorders.

Beans Benefit Heart Health and Weight Loss

The high protein and fiber content of beans have been shown to aid in weight loss as well.^4,10  Protein can boost metabolism and reduce appetite, while fiber promotes feelings of “fullness” by satiating hunger and slowing digestion. Regular consumption of beans has been shown to reduce the risk of heart disease and stroke by raising HDL (“good”) cholesterol levels, reducing total and LDL (“bad”) cholesterol levels, and lowering blood pressure.^11,12

Beans Assist in Cell Regeneration and Brain Health

Beans are loaded with folate (vitamin B9), which promotes production of red blood cells and mitosis, or the healthy division of cells, throughout the body.^4,13 Through this division, new cells form while we are in utero, as well as after we are born, as our bodies grow and develop; mitosis also allows our bodies to repair damaged cells throughout life. Additionally, folate produces dopamine, a chemical that helps calm the brain.

A half cup of pinto, pink, black, or navy beans, for example, contain 147, 142, 128, or 127mcg of folate, respectively.⁴ The daily recommended amount of folate for adults (who are not pregnant and/or lactating) is 400mcg.^4,13

Beans Supply antioxidants

Beans are an optimal source of antioxidants.^4,14–16 The polyphenols/polyphenolic compounds (a micronutrient found in plants) and anthocyanin pigments (a type of flavonoid) in beans assist our bodies in combating oxidative stress, which is defined as  “an imbalance between production and accumulation of oxygen reactive species (ROS) in cells and tissues and the ability of a biological system to detoxify these reactive products.”¹⁷ Oxidative stress promotes inflammation, which can lead to the development of neurodegenerative diseases (Alzheimer’s and Parkinson’s), heart disease, arthritis, asthma, diabetes, high blood pressure, stroke, and cancer.^14–16 The antioxidants found in beans can also improve the body’s stress response.

Akin to fruits and vegetables, the more colorful the bean, the antioxidant-packed it is. Red (e.g., kidney and pinto), brown, and black beans contain higher amounts of antioxidants, compared to white beans (e.g., navy, cannellini). Beans are also good sources of other types of flavonoids, such as quercetin, myricetin, cynidine, procyanidin, naringenin, catechin, hesperetin, and kaempferol—all of which assist in cell signaling and reducing inflammation.^15,16

Beans Contain Many Important Vitamins and Minerals

Zinc decreases pro-inflammatory immunity cells, reduces risk for infection, and is considered an antioxidant.^18,19  This nutrient has also been shown to reduce anxiety and anxiety-related symptoms. Being a trace mineral, the body needs small amounts.¹⁹

Copper is an essential nutrient. To function properly, certain enzymes in our bodies require the addition of copper to function properly. Once combined, they become cuproenzymes. Cuproenzymes  “…are involved in energy production, iron metabolism, neuropeptide activation, connective tissue synthesis, and neurotransmitter synthesis.”²⁰ Cuproenzymes also play a role in brain development, gene expression modulation, and immune functioning.²⁰

Magnesium, a mineral, is one of the most noteworthy anti-inflammatory nutrients our bodies need due to its ability to moderate c-reactive protein (CRP) levels.^21–23 Elevated CRP levels are linked to inflammation, and chronic elevation of CRP levels has been linked to the development of certain cancers. Magnesium also helps our brains combat memory loss as we age. Increasing magnesium intake has been shown to enhance the brain’s ability to memorize information and learn. Apparently, only 32 percent of the US population meets the daily recommended amount of magnesium, which is 400–420mg for men and 310–320mg for women.^21–25

Vitamin B6 is primarily involved in protein metabolism; however, it also plays a role in cognitive development, regulation of homocysteine blood levels, immune functioning, and red blood cell formation.²⁶ 

Vitamin E helps prevent oxidative stress, reduce inflammation, inhibit platelet aggregation, and enhance immune functioning, and thus has been shown to be effective in reducing the risk for several diseases, including Alzheimer’s disease, cardiovascular disease, certain types of cancers, and cataracts.²⁷

Vitamin K1 exhibits anti-inflammatory effects and enhances cognitive performance.^28–30 In particular, vitamin K1 is directly linked to improved memory in adults. Moreover, those with sufficient intake of vitamin K1 are less likely to experience cogitative decline.^28–30

Selenium is an essential trace element that plays an important role in our immune functioning, reproduction system, thyroid hormone metabolism, DNA synthesis, and protection from oxidative damage.^31,32

Beans Are versatile and easy to prepare

Beans can be purchased in the can or in dried form, and from a nutrition standpoint, they are comparable. However, canned beans tend to have a lot of added sodium, which might be problematic for some individuals. Ounce for ounce, canned bean are also more expensive than dried beans. But when it comes to convenience, canned beans have the edge: they require little preparation, and can be eaten cold, straight from the can, or heated on the stove. Dried beans, on the other hand, require a bit of planning and preparation.

To prepare dried beans, first sort and examine them carefully to remove any little rocks or debris that might have gotten mixed in during the manufacturer drying and sorting process. Next, soak them in water. Technically, you can cook dried beans without soaking them first (and some beans, such as lentils, don’t need to be soaked), but soaking them will greatly reduce the cook time (your hungry family will thank you). There are two ways to soak beans: the slow way and the quick(er) way. To soak them the slow way, cover them with cold water in a large bowl (discard any beans that immediately float to the top) and allow them to soak in the refrigerator overnight. To soak them the quick way, place them in a pot of water (discard the floaters), bring the water to a boil, remove the pot from the heat, and allow the beans to soak in hot water for an hour. Either method is fine, though some believe the quick method reduces some of the beans’ nutritive qualities.^1–4  

Once soaked, strain and rinse the beans, place them in a large pot, and cover them with about two inches of cold water. Bring to a boil then reduce heat and gently simmer for 30 minutes to 2 hours (cook time depends on bean type) until very tender. Add more water, if necessary, during the cooking process to keep them from drying out. Once the beans are done, season them to taste and eat ‘em up. Serving suggestions include:

• Mixing them into rice and wrapping the mixture in a whole-wheat tortilla
• Adding them to soups, chili, salads, or pasta dishes
• Adding them to a vegetable stir fry
• Serving them as a side dish
• Blending them to make dips.

Editor’s note. Raw or  undercooked beans contain phytohemagglutinin, a potentially toxic lectin that can cause stomach pain, nausea, and vomiting.³³ Dried beans should be thoroughly cooked before consuming. Fava beans, in particular, might be harmful for people who lack the G6PD enzyme. This can cause a condition known as favism, which destroys red blood cells throughout the body.³⁴ Canned beans, on the other hand, have already been cooked.

SOURCES

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