Are Black Beans Healthy? Nutrition, Benefits, and More

Black beans are a legume, also known as a pulse — a food group with a unique nutritional profile (2).

One cup (172 grams) of boiled, unsalted black beans contains (3):

• Calories: 227
• Protein: 15 grams
• Fat: 1 gram
• Carbs: 41 grams
• Fiber: 15 grams
• Folate: 64% of the daily value (DV)
• Copper: 40% of the DV
• Thiamine: 35% of the DV
• Manganese: 33% of the DV
• Magnesium: 29% of the DV
• Iron: 20% of the DV
• Phosphorus: 19% of the DV
• Potassium: 13% of the DV
• Vitamin B6: 7% of the DV
• Calcium: 2% of the DV
• Selenium: 2% of the DV

As you can see, black beans are exceptionally high in fiber and plant-based protein, two nutrients that help lower chronic disease risk and that many Westernized diets lack (1).

Their protein is highly digestible, with a digestibility of 79%. In fact, black beans are considered an ecologically sustainable protein source compared with animal-based sources (4, 5).

This nutritious legume provides both soluble fiber, insoluble fiber, and resistant starch, all of which are associated with many of its benefits (4).

Black beans also provide calcium, selenium, and numerous B vitamins. However, their overall mineral content can vary greatly depending on the beans’ origin (4).

In addition, despite their high iron content, they contain certain antinutrients, which are compounds that may hinder the mineral’s absorption (4, 6).

Summary

Black beans are rich in plant-based protein, fiber, and numerous vitamins and minerals. However, their mineral content may vary, and your body may not absorb their iron well due to the presence of antinutrients.

Black beans have several health benefits to offer, generally linked to their antioxidant and fiber content.

Rich in antioxidants

Black beans are rich in antioxidants. These are compounds that can neutralize free radicals to counteract oxidative processes linked to chronic diseases (4).

That’s why black bean antioxidants may help lower the risk for heart disease, type 2 diabetes, and some types of cancer (4).

In particular, black beans offer a significant amount of polyphenols, especially anthocyanins (4, 7, 8).

Anthocyanins are linked to potential type 2 diabetes benefits. They’re primarily located in the beans’ seed coat and are responsible for their dark color. They’re also responsible for the color of red and pink bean varieties (4).

Another antioxidant group present in black beans is flavonoids, including catechin, quercetin, myricetin, and kaempferol. These have potential cancer-fighting and heart-protective properties (4, 8).

Note that the beans’ antioxidant content may decrease with cooking and storage, with greater losses happening at higher temperatures. So, be sure to store them in a cool pantry (4).

May promote heart health

Adding black beans to your diet may help lower blood cholesterol and high blood pressure levels.

For example, saponin compounds in black beans act as antioxidants with cholesterol-lowering capacities. The beans’ fiber may also help reduce total cholesterol and triglyceride levels (4).

In fact, studies show that for every 10 grams of total fiber consumed, the risk of mortality from heart disease may decrease by 27%. Similarly, consuming 5–10 grams of soluble fiber per day may reduce LDL (bad) cholesterol levels by 5% (4, 9).

Other evidence shows that people who consume beans, including black beans, had an 11% lower risk of heart disease than those who did not consume beans (10).

However, another study found that consuming 1/2 cup (113 grams) of beans daily had no significant effect on cholesterol levels. So, it is possible that heart health benefits may only be seen if you eat more than this serving size of beans daily (10).

Research has also found an inverse correlation between bean fiber intake and blood pressure, specifically that higher fiber intakes result in lower readings (4).

In addition, flavonoids in black beans may help prevent platelet aggregation and encourage muscle relaxation, which further contributes to the blood-pressure-lowering effect (4).

Similarly, another study determined that consuming 3/4 cup (129 grams) of black beans had a vasorelaxant effect, meaning that it helped relax the muscles within blood vessels to lower blood pressure (11).

May help manage blood sugar levels

Antioxidants and fiber in black beans may support blood sugar control.

Firstly, their anthocyanidin content has been shown to boost insulin sensitivity, meaning that they improve how your cells respond to the hormone insulin. This can lead to lower blood sugar levels after a meal (7, 8).

In addition, anthocyanidins may inhibit alpha-amylase, maltase, and sucrase activity — three enzymes that support carb digestion — which further promotes lower blood sugar levels after eating (7).

Secondly, the fiber in black beans may improve the glycemic index (GI) of a meal (1, 4).

The GI measures how a food increases your blood sugar levels.

Black beans have a GI within the 29–38 range, so they are considered a low GI food. This means that they cause a small and steady rise in your blood sugar (4).

Studies show that consuming meals containing as little as 1/2 cup (86 grams) of black beans may reduce the GI of the meal, helping control blood sugar levels up to 120 minutes after eating (1).

This happens because the beans’ fiber increases stool volume and transit time along the intestine, allowing for slow glucose absorption. In addition, the fiber slows down the digestion rate, further slowing down the release of glucose into the bloodstream (4).

Summary

Black beans’ fiber and antioxidants help lower cholesterol, blood pressure, and blood sugar levels.

Like most legumes, black beans contain compounds known as antinutrients. They’re named this because they impair digestion and the absorption of certain minerals in the body (4, 12, 13).

Antinutrients found in black beans include (4, 12, 13):

• Lectins: resist digestion and may alter gut function
• Protease inhibitors: interfere with legume digestion
• Tannins: inhibit iron absorption and negatively impact iron stores
• Phytic acid: inhibits the absorption of calcium, iron, and zinc and decreases protein bioavailability

Conveniently, cooking reduces the beans’ antinutrient content. For example, soaking and boiling beans effectively reduces their antinutrient content. Germination and fermentation also help significantly (4, 13).

It’s worth considering that although black beans are a rich source of plant-based protein, they’re not a complete protein source. That means they don’t contain all nine essential amino acids that your body needs from food (14).

For this reason, it is important to eat a balanced diet with a variety of plant-based foods that will provide all of the essential amino acids — as opposed to eating black beans only.

Summary

Black beans contain antinutrients that impair digestion and inhibit mineral absorption, but cooking methods can improve this. Since black beans are not a complete protein source, aim to eat a variety of plant-based foods to get all essential amino acids.

Pinto beans are another bean variety commonly consumed in Mexico. They share many similarities with black beans.

In terms of nutritional content, boiled pinto beans provide virtually the same amount of protein, carbs, fiber, and fat as black beans. They also offer a similar mineral content, with slightly higher amounts of folate, calcium, and copper (3, 15).

Pinto beans have a high antioxidant content as well. So, they share many of black beans’ health benefits, including their cholesterol- and blood-sugar-lowering properties (16, 17, 18).

Because they are another type of bean, pinto beans also possess the same antinutrients as black beans (12, 13).

This means you should feel free to choose pinto beans over black beans if you like them better — you’ll still enjoy the same health benefits.

Summary

Pinto and black beans have similar nutritional profiles and provide the same health benefits.

It’s best to soak dry black beans before cooking them to reduce their antinutrient content. This means that preparing black beans may be a bit time-consuming.

While covering the beans with water and letting them soak overnight is one approach, you can also do a quicker soak.

Here are the directions on how to quick-soak and cook dry black beans:

1. Place the beans in a large pot and cover with water. Bring the water to a boil and continue boiling for about 2 minutes. Then, remove the pot from the heat and let the beans sit in there for a couple of hours.
2. Drain the beans and place them in a pot with fresh water. Once more, bring the water to a boil. Then, lower the heat and cover.
3. Simmer the beans for 2 hours, adding more boiling water if needed. Stir the beans from time to time to prevent them from sticking together or to the pot.
4. Once tender, drain the beans. Season with salt or seasoning of choice and enjoy.

Alternatively, canned black beans are an easier, more convenient, and more accessible alternative to cooking dry black beans from scratch. This is because canned beans are precooked.

However, while they’re also highly nutritious, they tend to be high in sodium. Eating too much sodium may contribute to high blood pressure in some people. Be sure to drain and rinse the beans before eating them to reduce their salt content (19).

Black beans make a great addition to salads, curries, and quesadillas. You can also serve them on corn tortillas, mixed with rice, or in chilies or stews.

Summary

Cooking black beans is easy but time-consuming. Remember to soak them beforehand to remove some of their antinutrients.

Black beans are among the most frequently consumed dry pulses around the world.

They’re considered nutritional powerhouses that are rich in plant-based protein, fiber, and antioxidants that help manage blood pressure, sugar, and cholesterol levels.

Like most legumes, black beans contain antinutrients that may affect your digestion and mineral absorption. Soaking and boiling them before eating reduces their antinutrient content and makes them nice and tender.