The common Bean (Phaeseolus vulgaris) seems to have developed independently in Central America and in Asia (Thailand). There are thousands of varieties and they all belong to the Legume family that also include Peas and other pulses.

Some kinds of beans need to be hard boiled for 20 – 30 minutes then washed out before being used for cooking. This removes the toxins present in some beans.
Healthy Edibles,complied by Chris Dixon (For Educational Purposes Only) notes these health benefits:

Plant based protein sources are not “complete proteins”, however, proteins from beans, soya, tofu, hemp, lentils & legumes allow carbohydrate to enter the bloodstream at a steady rate, delaying hunger & sustaining energy levels, so insulin levels do not rise rapidly, which helps manage blood sugar levels …
…Beans and soya products aid collagen & elastin production for skin, joints, ligaments, tendons, cartilage, hair, eye cornea, blood vessels, bonnes & inter-vertebral discs of the spine.
Beans also reduce swelling/water retention in feet, legs, hands & breast; aid prevention of Crohn’s disease, osteoporosis & ulcerative colitis (Irritable Bowel Syndrome). Beans aid healthy nerves, hair, kidney & cholesterol management. They also reduce stress & the risk of anaemia & they help manage high blood pressure.

Beans have supported high cultures on both sides of the Earth from the beginning. They store well (glass jars or other sealed containers) and can remain viable as seeds to germinate for years. You can eat beans fresh, you can cook the dried seeds and you can also sprout the seeds for tremendous health benefits and fresh greens in the middle of winter. The genius of the Chinese people gave us the sprouting innovation.

Beans are one of those rare foods that have carbohydrates for calories but also include protein as well. Canadians eat their beans from a can but I like to cook them fresh into a simple chili, with all organic ingredients. Not sure how much Canadians eat but we use several pounds a year to have them at least once a week.