Black beans

What’s new and beneficial about black beans

• Research on black bean carbohydrates keeps expanding the list of health benefits provided by this legume for our digestive tract. Some much-deserved attention here has been focused on resistant starch. Over 70% of the calories in black beans come from carbs, and most of these carbs consist of starch. However, black beans are unusual in their starch content, because a large portion of their starch comes in the form of “resistant starch.” Like this name suggests, a large portion of the starch in black beans is not easily digested, and passes through our upper digestive tract without being broken down. Since this breakdown does not happen, the starch is not converted into simple sugars and our blood sugar level can avoid a quick rise. Our insulin response can also avoid any abrupt increase. Together, these processes provide black beans with a value of “low” on the glycemic index. Not only do we get these upper digestive tract benefits—we get benefits in our lower digestive tract as well because the resistant starch in black beans can be broken down by bacteria when it finally reaches our large intestine and the result is an increased supply of fuel for the cells of our large intestine. (This fuel comes in the form of short chain fatty acids, or SCFAs, that are made from the resistant starch.)
• We tend to think about brightly colored fruits and vegetables as our best source of phytonutrients, but recent studies have confirmed the status of black beans as a strong contender in terms of their phytonutrient benefits. The outermost part of the bean that we recognize as its surface is technically referred to as its “seed coat.” Recent studies have looked closely at the seed coat composition, and have shown it to be rich in three particular anthocyanins: delphinidin, petunidin, and malvidin. Anthocyanins are an important group of flavonoids that provide deep shades of red and purple in many foods, and in the case of black beans, these anthocyanins are largely responsible for the rich black color that we associate with black beans. (Many other components contribute to the ultimate black color that we see, including minerals present in black beans.) In terms of their color-providing phytonutrients, it makes sense to think about black beans in the same category as red cabbage, red onions, or even blueberries because along with these colorful foods, they feature a rich flavonoid composition.
• Among all 100 WHF, black beans rank in the top third as a source of zinc, and they provide about the same amount of zinc (approximately 2 milligrams) as 4 ounces of turkey or shrimp. However, because black beans also rank in the top third of all foods as a source of calories, they are prevented from appearing as a concentrated source of zinc in our WHF Rating System, which takes this calorie factor into account. Like researchers worldwide, however, we consider black beans to be a potentially important source of dietary zinc, and in this context, we have been very glad to see results from recent studies showing strong bioavailability of zinc from black beans despite the phytate content of black beans. Phytates are important storage molecules for phosphorus in many plants, and they can also act as antioxidants, especially in the protection of fats from oxidation. However, phytates have raised some nutritional concerns in past research studies based on their ability to bind certain minerals and thereby lower mineral absorption. Impaired zinc absorption has been one of these concerns. Recent studies suggest that the phytates in black beans do not directly lower the bioavailability of zinc, which is great news for anyone who enjoys this legume and also relies on it as a source of zinc. Current study results suggest that only under special circumstances when zinc, phytates, and calcium form special complexes in our intestine does the absorption of zinc become impaired. This more complicated set of circumstances is the focus of ongoing studies. But in the meantime, it appears that black beans are able to provide us with valuable amounts of zinc.
• Improved fat metabolism is another health benefit that you are very likely to receive by incorporating black beans into your meal plan. Recent studies in this area have focused on the outer surface of black beans (called their “seed coat”) and two groups of phytonutrients: flavonoids and saponins. In the flavonoid category, studies have paid special attention to myricetin, quercetin, and kaempferol. In the saponin category, the research focus has been on soyasaponins and phaseoside I. Two trends have been seen in multiple studies, still in the animal and laboratory stages of research. First, these black bean phytonutrients appear to block expression of genes that would result in the production of enzymes designed to increase our blood fat levels. Second, these black bean phytonutrients also appear to promote expression of genes that produce enzymes for “reverse cholesterol transport.” In other words, black bean phytonutrients help deliver cholesterol back to our liver from other locations in the body, thus taking some cholesterol out of circulation and lowering our blood level. While we do not yet have large-scale human studies to document these specific health benefits in humans, we do have large-scale human studies showing a general tendency toward better overall fat metabolism when legumes are included as part of a routine meal plan.

Recommendations

Many public health organizations recommend beans and legumes as a key food group for helping prevent disease and for optimizing health. We fully agree with this special treatment of beans and legumes based on their well-documented health benefits. The 2015-2020 Dietary Guidelines for Americans developed by the U.S. Department of Health and Human Services (DHHS) and U.S. Department of Agriculture (USDA) recommend 1.5 cups of legumes per week within a non-vegetarian diet, and 3.0 cups per week within a vegetarian diet. Because our approach to healthy eating at WHF places especially strong emphasis on vegetable intake, and because we tend to avoid large portions of meat in our meal plans, our chose this higher level of legume intake (3 cups per week) as our WHF recommended amount. To see how easily this amount can be incorporated into a delicious and easy-to-follow meal plan, take a look at our WHF Meal Plan! We feature three of our WHF - black beans, navy beans, and lentils - in our WHF Meal Plan Recipes.

While black beans are a fantastic option for helping you to meet your weekly bean and legume goals, other nutrient-rich foods in this beans and legumes group include dried peas, garbanzo beans (chickpeas) kidney beans, lentils, lima beans, navy beans, pinto beans, soybeans, tempeh, and tofu. We recommend enjoyment of a variety of Beans & Legumes each week for optimal nourishment.

Black Beans, cooked
1.00 cup
(172.00 grams)

Calories: 227
GI: low

NutrientDRI/DV

 molybdenum287%

 folate64%

 fiber53%

 copper40%

 vitamin B135%

 phosphorus34%

 manganese33%

 protein30%

 magnesium29%

 iron20%

Food Rating System Chart

• Health Benefits
• Description
• History
• How to Select and Store
• Tips for Preparing and Cooking
• How to Enjoy
• Nutritional Profile

Health benefits

General fiber and protein benefits from black beans

No food group matches legumes for the simultaneous delivery of protein and fiber. One cup (172g) of cooked black beans provides nearly 15 grams of each. This single serving covers 53% DV of fiber and 30% DV of protein. No other food group offers comparable concentrations of both macronutrients in the same food.

Both macronutrients regulate the speed of digestion, moderating blood sugar spikes and supporting colonic health. But the specific forms of fiber and protein in black beans have properties beyond those of generic fiber and protein sources.

Specific fiber and protein benefits from black beans

The type of fiber and protein in black beans is as consequential as the quantity. One cup provides about 41 grams of total carbohydrates, of which 15 grams are fiber, leaving 26 grams of non-fiber carbohydrate, mostly starch. Ordinarily, this starch load would elevate the glycemic index. But a large fraction of black bean starch is “resistant starch,” meaning it passes through the upper digestive tract without enzymatic breakdown into simple sugars. Blood glucose and insulin responses remain moderate as a result, and black beans score “low” on the glycemic index.

In addition to these upper digestive tract benefits, we also get black bean benefits in our lower digestive tract. When the resistant starch in black beans finally reaches our large intestine, it gets broken down by bacteria and provides an increased fuel supply for the cells of our large intestine in the form of short chain fatty acids, or SCFAs. The great likelihood is for these combined digestive tract benefits to eventually translate in reduced risk of colorectal cancer in individual who regularly consume black beans and other legumes.

On the protein front, recent studies show black beans to contain unique peptide components (small sequences of amino acids that are used to form proteins) that further improve regulation of blood sugar and insulin levels. Most of these unique peptides consist of 5-6 amino acids, and they act to inhibit the production of glucose transport molecules like GLUT-2. By interfering with GLUT-2 production, these black bean peptides can help lower glucose absorption from the digestive tract and thereby help steady blood sugar levels.

Unique phytonutrient support from black beans

Black beans are not typically grouped with fruits and vegetables for phytonutrient content, yet they provide meaningful amounts of several classes. Myricetin, quercetin, and kaempferol are among the flavonoids provided by this legume, along with phenolic acids like hydroxycinnamic acid, ferulic acid, sinapic acid, and chlorogenic acid. Saponins like soyasaponin and phaseoside I are also included among the black bean phytonutrients. (Saponins are a subgroup in the larger phytonutrient category known as triperpenoids.) The outer surface of blacks beans—called their “seed coat”—is the most concentrated location for many of these phytonutrients. Particularly important in the seed coat of black beans are its anthocyanins. This flavonoid subgroup is largely responsible for the deep black color that is so striking in this legume. The chart below shows how some of the key anthocyanins in black beans compare in quantity to key anthocyanins found in other anthocyanin-rich foods.

Anthocyanin content of black beans and other foods

(Milligrams per 100 grams of food)

Anthocyanin

Blueberries

Red Cabbage

Red Onions

Black Beans

Malvidin

67.6

0

0

10.6

Delphinidin

35.4

0

4.3

18.5

Pelargonidin

0

0

trace

0

Peonidin

0

0

2.1

0

Petunidin

31.5

0

0

15.4

Cyanidin

8.5

209.8

3.2

0

Source: Bhagway S, Haytowitz DB, and Holden JM. (2014). USDA Database for the Flavonoid Content of Selected Foods. Release 3.1. Nutrient Data Laboratory, Beltsville Human Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture (USDA), Beltsville, Maryland.

As you can see in the above chart, the total quantity of anthocyanins in black beans is not as high as the total quantity in blueberries or red cabbage, yet it is still substantial and includes a variety of different anthocyanins.

Black beans deliver anthocyanin phytonutrients at levels more commonly associated with deeply pigmented fruits and vegetables.

Other health benefits from black beans

For beans and legumes as a whole (including all types of dried beans and dried peas), research shows potential health benefits in two key areas: (1) cardiovascular diseases, and (2) blood sugar problems, including type 2 diabetes. Reduced risk of all of the following cardiovascular diseases has been associated with overall bean and legume intake: coronary heart disease, ischemic heart disease, hypercholesterolemia, and atherosclerosis. And in addition to type 2 diabetes, better glucose tolerance and improved insulin sensitivity have both been connected to bean and legume intake. Specifically, for black beans, we have also seen several studies showing improvement in multiple lab indicators for metabolic syndrome, including lab values related to blood fat levels and blood sugar levels.

The relationship between black bean intake and risk of cancer is not as well documented as the other chronic disease relationships described above. In animal and lab studies, black bean extracts have been associated with decreased inflammation in the colon and lower risk of colitis, and studies point in the direction of the possibility of reduced colon cancer risk following routine intake of black beans. Also, worth noting in the context of colon cancer prevention are the general anti-inflammatory properties of black bean flours in animal studies. Mice fed this form of black beans have shown increased levels of anti-inflammatory messaging molecules in their blood including interleukin 10 (IL-10) as well as decreased levels of pro-inflammatory messaging molecules including interleukins 6, 9, and 17a (IL-6, IL-9, and IL-17a) as well as interferon gamma (IFN-gamma). These anti-inflammatory effects may turn out to be important for management of cancer risk, since the development of certain cancers may start out with underlying conditions of chronic inflammation and chronic oxidative stress. Still, it is important to remember that large-scale human studies in this cancer area have yet to be undertaken with a specific focus on black beans.

The American Heart Association estimates that approximately one-third of all U.S. adults have a set of chronic disease risk factors called Metabolic Syndrome. These risk factors include high blood sugar, high blood pressure, low blood levels of protective HDL cholesterol, high blood levels of triglycerides, and excess body fat around the waist. When taken as a group, this set of conditions associates with increases in our risk of type 2 diabetes, stroke, and several types of heart disease. In a recent study on a very small group of adults previously diagnosed with Metabolic Syndrome, researchers found that daily inclusion of soup that had been reconstituted from dried black beans helped steady blood sugar and insulin levels. Specifically, insulin secretion following consumption of black bean soup was decreased in comparison with a matched non-bean soup, as was blood sugar elevation. In addition, antioxidant capacity in the bloodstream was found to increase following consumption of black bean soup. Once again, this very small scale study cannot provide us with conclusive evidence about the role of black bean consumption for improved management of Metabolic Syndrome, but the results seem to be pointing in the direction of potential benefits.

Description

We owe a major debt to the genus/species of plant known as Phaseolus vulgaris since this single genus/species provides us with a wide variety of both dried and fresh beans—including, of course black beans. Other dried beans belonging to this single genus/species include navy beans, kidney beans, and pinto beans. In the fresh bean category, green beans of many types—including snap beans, string beans, bush beans, and pole beans—are universally known as Phaseolus vulgaris. In other words, we end up with a remarkable degree of variety here among beans that are as closely related as foods can be.

Perhaps the most distinguishing characteristic of black beans is their rich black color. As mentioned earlier in this profile, anthocyanins in the seed coat of black beans combine with their mineral content and other components to create this dramatic black color. You’ll often hear black beans being referred to as either “turtle beans” or “black turtle beans” since their dark surface can be shiny and reminiscent of a shell. Midnight Black, Gold Vault Black, Cherokee Trail of Tears, Eclipse Black, Condor Black, Zorro Black, and Zenith Black are varieties of black beans that you are likely to find in seed stores and in commercial black bean products.

Black beans are commercially available in a wide variety of forms, including not only canned and dried, but also as flakes, flour, and even pre-made pasta noodles. Dried black beans typically need to be presoaked, drained, and the cooked prior to consumption. (For full details, please see our “Tips for Preparing and Cooking” section.) Canned black beans come fully cooked, and this greater level of convenience has led many readers to ask us whether they will be giving up too many health benefits by choosing black beans in canned form. The one detailed study that we have seen in this area showed overall lower nutrient levels in canned versus dried-and-cooked black beans. However, these lower levels were not so dramatically different as to rule out canned black beans as a healthy way to bring black beans into your meal plan.

We would add two additional comments in this context. First, we view the difference between fresh versus canned fruits/vegetables as different from the difference between dried versus canned beans. In the case of fruits and vegetables, we are talking about a large jump between fresh and canned. In the case of beans, we are talking about a much smaller step since both types of beans have gone through the drying and cooking process. In other words, we don’t have anything corresponding to “fresh” in the case of dried versus canned beans.

Second, we do not consider the canning of black beans to be a highly invasive process. Canned black beans are typically sorted, graded, and cleaned just like dried black beans, and prior to being cooked inside of their sealed can, they are hydrated, blanched for 3-8 minutes in water heated to 180-199°F (82-93°C), cooled, and then placed in their can together with a brine or other type of liquid. Low salt and no salt versions of canned black beans have either low-salt or salt-free liquids added to the can prior to cooking; we would recommend the “no added salt” versions of canned black beans to anyone who has decided to go with the canned version but wants or needs to avoid added salt. Calcium (for example, in the form of calcium chloride) may sometimes be added to canned black beans to help preserve their firmness, and sodium bicarbonate may sometimes be added to decrease acidity and improve water absorption by the black beans when they are cooked. As a general rule, these added ingredients would not be likely to cause problems for most individuals, but their presence in canned black beans could also be substantially reduced by thorough rinsing. In most parts of the U.S., it is not difficult to find organic canned black beans that have been cooked without the addition of salt, calcium chloride, or sodium bicarbonate. Sometimes you may find “no added salt” organic black beans canned together with a sea vegetable like kombu. A common type of method for cooking black beans in this can would have involved about 45 minutes of cooking at approximately 240°F (116°C).

When all of these details about canned black beans are considered as a whole, they point to a relatively low level of processing and creation of a very reasonable alternative to home-cooked dried black beans, even though the canning process may moderately lower multiple nutrient levels.

History

Black beans are native to North, South, and Central America. Their origins have been traced to many locations in Mexico, as well as Costa Rica, El Salvador, Guatemala, Honduras, and Nicaragua. In South America, the origin of black beans has been traced to the present-day countries of Venezuela, Bolivia, Argentina, Columbia, Ecuador, and Peru. Of course, black bean cultivation is no longer limited to North, South, and Central America. Today, black beans are cultivated and enjoyed worldwide in many different types of cuisines.

For two reasons, statistics on black bean production can be difficult to evaluate. First, many organizations that monitor dried bean production combine all dried beans into a single category and do not specifically track the production of black beans versus other varieties. Second, dried beans are often combined together with dried peas and dried lentils and monitored as “pulses”—one large overarching category for all of these foods combined. However, the overall statistics on dried beans and pulses suggest that China, Argentina, Brazil, and Mexico are key producers of black beans, followed by the United States. When all pulses are considered, the country of India would need to be added to this list. About 24 million metric tons of dried beans are produced each year on a worldwide basis.

U.S. consumers average approximately 1.4 ounces of total beans-plus-legumes per week, or less than 1/5 cup. As mentioned earlier in this profile, most public health recommendations suggest a large increase in this average amount, to at least 1.5 cups per week.

Within the United States, North Dakota, Michigan, Nebraska, Minnesota, Idaho, Colorado, California, and Washington are the major commercial dry bean-producing states.

How to select and store

Both dried and canned black beans are available throughout the year. Dried beans are generally available in prepackaged containers as well as in bulk bins. Just as with any other food that you may purchase in the bulk section, make sure that the bins containing the black beans are covered and that the store has a good product turnover to ensure the beans’ maximal freshness. Whether purchasing black beans in bulk or in packaged containers, make sure that there is no evidence of moisture or insect damage and that they are whole and not cracked.

As described earlier in the Description section of this profile, both home-cooked dried black beans and precooked canned black beans can play a health-supportive role in your meal plan. If you decide to go the dried and home-cooked route, we recommend that you store dried black beans in an airtight container in a cool, dry and dark place where they will keep up to 12 months. If you purchase black beans at different times, store them separately since they may feature varying stages of dryness and therefore will require different cooking times. Cooked black beans will keep fresh in the refrigerator for about three days if placed in a covered container.

Tips for preparing and cooking

Preparation

Before washing dried black beans, spread them out on a light colored plate or cooking surface to check for, and remove, small stones, debris or damaged beans. After this process, place the beans in a strainer, rinsing them thoroughly under cool running water.

To shorten their cooking time and make them easier to digest, dried black beans should be presoaked (presoaking has been found to reduce raffinose- and stachyose-type oligosaccharides, sugar-related carbohydrates that have been associated with increased flatulence.) There are two basic methods for presoaking. For each method, you should start by placing the beans in a saucepan and adding two to three cups of water per cup of beans. The first method is to boil the beans for two minutes, take the pan off the heat, cover and allow to stand for two hours. The alternative method is to simply soak the beans in water for eight hours or overnight, placing the pan in the refrigerator so that the beans will not ferment. Before cooking the beans, regardless of method, drain the soaking liquid and rinse the beans with clean water.

We realize that there has been some debate in the public press over discarding of the bean soaking water. Some websites and commentators have argued that this soaking water contains too many valuable nutrients to discard. While we agree that nutrient loss does take place when the soaking water is discarded, we interpret the overall research results as showing a helpful trade-off between this undesirable nutrient loss versus the desirable loss of other substances that were removed from the dried black beans during the soaking process. For example, raffinose and stachyose oligosaccharides associated with flatulence from black beans can migrate from the beans into the soaking water, and their removal from the final cooked black beans can be helpful. However, we also understand how some persons may decide that they prefer to retain the soaking water for cooking.

Cooking for nutrient retention

To cook the beans, you can either cook them on the stovetop or use a pressure cooker. For the stovetop method, add three cups of fresh water or broth for each cup of dried beans. The liquid should be about one to two inches above the top of the beans. Bring the beans to a boil and then reduce to a simmer, partially covering the pot. If any foam develops, you can skim it off during the simmering process. Black beans generally take about one and one-half hours to become tender using this method. They can also be cooked in a pressure cooker where they take about one-half hour to prepare.

Regardless of cooking method, do not add any seasonings that are salty or acidic until after the beans have been cooked since adding them earlier will make the beans tough and greatly increase the cooking time.

If you decide to use canned black beans in your meal plan, it’s worth noting that your canned beans need to only be heated briefly for hot recipes, and they can also be used as is for salads or prepared cold dishes like black bean salads.

How to enjoy

Serving ideas

• Include black beans with your other favorite toppings next time you make a stuffed baked potato.
• Black bean soup or chili is certain to warm you up on cold winter days or anytime of the year you want to enjoy its nurturing essence.
• For a “mucho bueno” twist on traditional burritos, use black beans in place of refried pinto beans.
• Blend cooked black beans with tomatoes, onions and your favorite spices to create a delicious bean soup.
• In a serving bowl, layer black beans, guacamole, chopped tomatoes, diced onions and cilantro to make a delicious layered dip.

Recipes that feature black beans

• 10-Minute Huevos Rancheros
• Poached Huevos Rancheros
• 15-Minute Black Bean Salad
• Mexican Cheese Salad
• Zesty Mexican Soup
• Southwestern Salmon & Black Beans
• Black Bean Burrito, Indian Style
• Black Bean Chili
• Quick Black Bean Chili
• Spicy Black Bean Burrito

Nutritional profile

The seed coat (outermost surface) of black beans is an outstanding source of three anthocyanin flavonoids: delphinidin, petunidin, and malvidin. Kaempferol and quercetin are additional flavonoids provided by this legume. Also contained in black beans are hydroxycinnamic acids including ferulic, sinapic, and chlorogenic acid, as well as saponins including soyasaponins and phaseoside I. . Black beans also provide about 180 milligrams of omega-3 fatty acids per cup in the form of alpha-linolenic acid (ALA).

One cup of cooked black beans provides molybdenum (287% DV), folate (64% DV), fiber (53% DV), copper (40% DV), vitamin B1 (35% DV), phosphorus (34% DV), manganese (33% DV), protein (30% DV), magnesium (29% DV), and iron (20% DV).

Individual concerns

Oxalate content

Black beans have consistently been determined to have high oxalate content. Oxalates are naturally occurring organic acids found in a wide variety of foods, and in the case of certain medical conditions, they must be greatly restricted in a meal plan to prevent over-accumulation inside the body. Our comprehensive article about oxalates will provide you with practical and detailed information about these organic acids, food, and health.