If you recently decided to eat better foods as part of a health and fitness lifestyle, you may already know about legumes. Giving up highly processed foods with extra salt, fat, and sugar and replacing those empty calories with nutrient-dense foods like legumes is a good place to start your goal of eating real food and staying healthy.
This article is not meant to replace the advice of your healthcare professional, but will provide an overview on legumes and inform you about how adding these plants to your diet can benefit your health. Make sure to ask your doctor about legumes if you are planning a weight loss program. Legumes are a low-fat, high-protein source of vitamins, minerals, antioxidant compounds and dietary fiber, and can certainly be a part of almost any healthy diet.
What exactly are legumes?
A legume is a plant or its fruit or seed in the family Fabaceae (or Leguminosae). Legumes are grown agriculturally, primarily for their grain seed called pulse, which is the type of legumes people eat. Legumes are also grown for other reasons, including for livestock food and for enriching and developing good soil for growing other crops. Growing soil, that is, enhancing poor dirt with soil-enhancing green manure plays a key role in crop rotation. Legumes are notable in that most of them have symbiotic nitrogen-fixing bacteria in structures called root nodules. This helps other plants grow stronger.
Legumes that are used for food are defined as plants that develop in a certain shape along a seam on two sides. A common name for this type of plant is a pod, although the term “pod” is also applied to a number of other plant types, such as that of vanilla ( which is not a legume; it is a capsule) and of the radish (a root crop).
Are legumes vegetables?
Yes, even though there are many types of legumes, the legume class of vegetables is extremely broad, encompassing some 13,000 varieties of beans, peas and lentils. For our purposes in this article, the legumes we’ll be looking at can be divided into two general categories: immature and mature varieties.
Fresh legumes, also known as immature legumes, include all types of edible pod beans and peas and shell beans that haven’t yet been dried. Wax beans, snow peas, edamame and fresh lima beans are all examples of immature legumes. These legumes are sometimes found at farmer’s markets and in the produce section of grocery stores.
Once legumes are harvested from the pod in their fully developed form, they can easily be dried and preserved for months. These legumes are often found in the pasta or rice aisles in grocery stores. Black beans, kidney beans, lentils and split peas are all examples of mature legumes and are often stored in clear plastic bags so that the consumer can see the product. Before these beans can be eaten, they must be soaked and properly cooked. (We’ll discuss the importance of proper cooking of legumes for food health and safety later on in this article.)
History of legumes for food
There are many nations and cultures that utilize legumes in the diet. Historically, this may have been because the dried beans can be kept through the winter months, ensuring the survival of the community when fresh crops are not available. The quality of the food is not reduced by drying. In fact, some might even say the quality and taste of dried legumes is excellent.
In India, for example, legumes play a very important role in balancing the nutritional needs of a population that includes many vegetarians.
Legumes are used as the main ingredient in many Indian recipes. In India, there is a mind-body science for good health called Ayurvedic theory, and this theory emphasizes the importance of including legumes in human diets. This is because no Indian meal is complete without the perfect combination of proteins, carbs, vitamins and minerals, fats and fiber.
Legumes are sometimes called dal, a term for dried, split pulses and for various soups prepared from these pulses. These pulses form an important part of Indian, Nepalese, Pakistani, Sri Lankan and Bangladeshi cuisines. Hence, dal is considered a staple in these countries and is eaten almost every day.
Typically, a meal of legumes, whether there is meat in the dish or not, will be eaten with some type of grain. Think of the classic dish “rice and beans.” The pulses usually lack certain amino acids that the grain will supply. Legumes lack methionine, but contain amino acids like lysine. Cereals and grains are rich in methionine but lack lysine. Therefore, consuming cereals and pulses together makes up for this lack of amino acids in either.
There are many benefits of eating legumes. Online sources may disagree about the importance of legumes. There are many who claim that legumes can cause inflammation in the body, contain lectins which are related to leaky guy syndrome, and phytates which cannot be absorbed by the body and block absorption of nutrients. Others claim that if cooked right, legumes are a essential part of your diet and provide low fat protein source. Some of this anti-legume information may come from the meat producers of the world. Naturally they want consumers to appreciate their products and include them in a balanced diet. Some of the positive info may come from the growers of legumes want to encourage the consumption of their products and may over-emphasize the problems that may occur when a person eats too much meat. The debate on legume needs more research, but overall if cooked properly legumes are thought to be healthy in moderation.
Legumes are a meat substitute?
They can be. Legumes are an inexpensive source of quality plant protein. They can be a meat substitute, however, because the vitamin and mineral profiles of legumes and meat are comparable. Whereas meat is also a source of cholesterol and saturated fat, legumes are a cholesterol-free food that contains virtually no saturated fat.
For just over 110 calories, a 1/2-cup serving of cooked black beans delivers 32 percent, 15 percent and 14 percent of the daily values for folate, magnesium and thiamine, respectively, and about 10 percent each of the daily values for iron and potassium. Opting for legumes instead of meat two or three times a week may promote healthy cholesterol levels and help protect against heart disease.
It doesn’t matter if you prefer to eat meat or are a vegan or vegetarian; either way, legumes are a significant source of protein, dietary fiber, carbohydrates and dietary minerals.
Legumes and whole grains are considered complementary proteins, meaning that while neither contains all nine essential amino acids, they form a complete protein when consumed together, or at least in the same day. Soybeans are an exception, as they do provide a complete high-quality protein. Many legumes also contain significant amounts of antioxidant compounds. As with fruits and vegetables, more colorful legumes tend to be higher in antioxidants. Small red kidney beans are actually a better source of antioxidants than fresh blueberries. Like other plant-based foods, pulses contain no cholesterol and little fat or sodium. Nearly all legumes provide protein, fiber, B vitamins, iron, zinc, magnesium and potassium, but mature legumes tend to be particularly rich sources.
Legumes are also an excellent source of resistant starch which is broken down by bacteria in the large intestine to produce short-chain fatty acids (such as butyrate) used by intestinal cells for food energy.
Legumes may benefit metabolism
Preliminary studies in humans include the potential for regular consumption of legumes in a vegetarian diet to affect metabolic syndrome. There is evidence that a portion of legumes, as little as just one cup a day in a diet may help lower blood pressure and reduce LDL cholesterol levels.
If you find yourself feeling hungry all day and this is tempting you to eat more, legumes may be able to help. As an excellent source of complex carbohydrates, protein and fiber, legumes are a highly satiating food. This means that for a relatively low amount of calories legumes make you feel fuller longer and help prevent the hunger that can lead to unhealthy snacking and unwanted pounds.
For about 115 calories, a 1/2-cup serving of cooked lentils provides about 9 grams of protein, 20 grams of mostly complex carbohydrates and less than half a gram of fat. It also supplies nearly 8 grams of fiber, or 31 percent of the recommended daily value. Most legumes contain significant amounts of insoluble and soluble fiber. Eating legumes several times a week promotes bowel regularity and helps keep blood sugar levels in check.
If you don’t take a daily multi-vitamin, adding legumes to your diet might make you feel like you had a protein shake and a vitamin tablet together! Just one single cup of cooked lentils provides these estimated nutritional values:
18 grams of protein
16 grams of fiber
40 grams of carbohydrate
37 percent of your daily requirement for iron
90 percent of your daily requirement for folate
18 percent of your daily requirement for magnesium
21 percent of your daily requirement for potassium
10 percent of your requirement for Vitamin B1, B3, B5 and B6, phosphorus, zinc, copper and manganese.
10 percent of your requirement for Vitamin B3
10 percent of your requirement for Vitamin B5
10 percent of your requirement for Vitamin B6
10 percent of your requirement for phosphorus
10 percent of your requirement for zinc
10 percent of your requirement for copper
10 percent of your requirement for manganese
What about fiber?
Legumes also contain what is called resistant starch and soluble fiber. These things, while not actually an ingredient of nutritional value are important for other dietary reasons. Resistant starch and soluble fiber have a few things in common. They pass undigested through the stomach and small intestine until they reach the colon, where they feed the friendly bacteria residing there. Resistant starch is found in other foods like grains and seeds. The resistant starch in legumes “resists digestion” because it is bound within the fibrous cell walls.
Both resistant starch and soluble fibers are also very satiating and may reduce food intake, which in the long run can lead to weight loss. Additionally, they are very effective at moderating blood sugar levels after meals and may improve insulin sensitivity.
Disadvantages of eating legumes
Unpleasant side effects of eating legumes often include gas and bloating. This effect may be reduced by using digestive spices in cooking legumes, such as ginger and turmeric.
Legumes may not be all you need. Although legumes are good sources of protein, not all proteins are the same. There are at least 20 different amino acids that join to form various types of protein. Your body cannot make certain amino acids, known as the essential amino acids. You can only get these amino acids from your diet. Complete proteins contain all of the essential amino acids. Most complete proteins are animal-based foods and not legumes all by themselves. There are exceptions. Soybeans are a type of legume that is a complete protein.
Dangers of too much Phytic Acid
Phytic acid, or phytate, is found in all edible plant seeds, including legumes. It slows the absorption of iron, zinc and calcium from the meal and may increase the risk of mineral deficiencies in people over time. Strategies can be used to reduce the phytic acid content and increase the nutritional value of legumes. These include proper soaking, sprouting, fermentation, and cooking of legumes.
Legumes Must Be Properly Cooked
In order for you to get any benefit from legumes, they must be properly cooked.
According to the Mayo Clinic, a respected health resource in the United States, legumes can be cooked properly using one of the following methods:
Slow soak the beans by covering one pound of dried beans with ten cups water. Cover and refrigerate for at least four hours or overnight. This is likely the best method.
Quick soaking method: in a stockpot, bring one pound of dried beans and 10 cups of water to a boil. Cover and set aside and let beans soak for one to four hours at room temperature.
After soaking, drain and rinse the beans and add to a stockpot. Cover the beans with three times their volume of fresh water. Add herbs or spices as desired. Bring to a boil. Then reduce the heat and simmer gently, uncovered, stirring occasionally, until tender. The cooking time depends on the type of bean, but start checking after 45 minutes. Add more water to keep the beans from becoming dry.