Beans are seeds from the Fabaceae family, commonly known as the legume, pea, or bean family. They are an affordable source of protein, fibre, iron, and vitamins that offer many health benefits.
Beans contain amino acids, which are the protein building blocks that the body uses to heal and to make new tissues, such as bone, muscle, hair, skin, and blood. Protein is an essential nutrient.
There are many types of beans. Dried beans need cooking to make them tender enough to eat. Canned and frozen beans are typically ready to eat after warming on the stove or in the microwave. Some of the most popular bean varieties include:
Lima beans
black beans
black-eyed peas
soybeans
kidney beans
garbanzo beans
navy beans
pinto beans
red beans
There are 20 amino acids and nine of these are essential. There are also two types of protein sources: complete and incomplete.
Animal products, soy, and quinoa are all complete proteins, which means they contain all nine essential amino acids.
However, of all the types of beans, only soybeans contain all nine amino acids.
People can combine incomplete proteins with nuts, seeds, dairy products, or grains at a single meal or throughout the day to make complete proteins.
For example, a person can:
- eat beans with rice or couscous for lunch
- have black beans at lunch with almonds or cheese
Beans make an excellent source of protein for vegetarians and vegans. They are also lower in calories and saturated fat than some other protein sources, such as meat and full fat or low fat dairy products.
Examples of the protein content of beans are:
A 1-cup, or 40 grams (g), serving of canned black beans provides 14.5 g of protein, 16.6 g of fibre, and 4.56 milligrams (mg) of iron.
A 1-cup, or 155 g serving of shelled edamame beans provides 18.5 g protein, 8.06 g fibre, and 3.52 mg iron.
Some studies have shown that beans act as antioxidants and anti-inflammatory agents. These effects could reduce the risk of cancer.
Research published in 2015 analysed whether beans might have antioxidant properties that fight intestinal cancer. The results suggested black beans had the highest antioxidant activity.
A 2016 study also found that chemicals in Northeast China black beans could slow the growth of colorectal cancer by preventing cancer cells from multiplying.
Reference:
Dan X, Ng TB, Wong JH, Chan YS, Cheung RC, Chan WY. A hemagglutinin isolated from Northeast China black beans induced mitochondrial dysfunction and apoptosis in colorectal cancer cells. Biochim Biophys Acta. 2016 Sep;1863(9):2201-11. doi: 10.1016/j.bbamcr.2016.05.019. Epub 2016
