GREEN BEANS

Green beans:
Green beans, also known as French beans (British English), string beans in the northeastern and western United States, snap beans or squeaky beans, are the unripe plant of specific cultivated varieties of the common bean (Phaseolus vulgaris).
Green bean varieties have been bred especially for the fleshiness, flavor, or sweetness of their pods. Haricots verts, French for "green beans", may refer to a longer, thinner type of green bean than the typical American green bean. It is known in some parts of the world as the squeaky bean due to the noise it makes on one's teeth whilst eating.
The first "stringless" bean was bred in 1894 by Calvin Keeney, called the "father of the stringless bean", while working in Le Roy, New York.
Varieties:
Over 130 varieties of green bean are known. Varieties specialized for use as green beans, selected for the succulence and flavor of their pods, are the ones usually grown in the home vegetable garden, and many varieties exist. Pod color can be green, golden, purple, red, or streaked. Shapes range from thin "fillet" types to wide "romano" types and more common types in between.
The following varieties are among the most common and widely grown in the USA.

Health benefits of Green beans:
1.Fresh green beans are very low in calories (31 kcal per 100 g of raw beans) and contain no saturated fat. Nevertheless, the lean vegetables are a very good source of vitamins, minerals, and plant derived micronutrients.
2.They are very rich source of dietary fiber (9% per100g RDA) which acts as a bulk laxative that helps to protect the mucous membrane of the colon by decreasing its exposure time to toxic substances as well as by binding to cancer-causing chemicals in the colon. Adequate amount of fiber has also been shown to reduce blood cholesterol levels by decreasing reabsorption of cholesterol-binding bile acids in the colon.
3.Green beans contain excellent levels of vitamin A, and health promoting flavonoid poly phenolic antioxidants such as lutein, zea-xanthin and ß-carotene in good amounts. These compounds help act as protective scavengers against oxygen-derived free radicals and reactive oxygen species (ROS) that play a role in aging and various disease processes.
4.Zea-xanthin, an important dietary carotenoid in the beans, selectively absorbed into the retinal macula lutea in the eyes where it thought to provide antioxidant and protective UV light filtering functions. It is, therefore, green beans offer some protection in preventing age-related macular disease (ARMD) in the elderly.
5.Snap beans are a good source of folates. 100 g fresh beans provide 37 µg or 9% of folates. Folate along with vitamin B-12 is one of the essential components of DNA synthesis and cell division. Good folate diet when given during preconception periods and during pregnancy helps prevent neural-tube defects among the offspring.
6.They also contain good amounts of vitamin-B6 (pyridoxine), thiamin (vitamin B-1), and vitamin-C. Consumption of foods rich in vitamin C helps the body develop resistance against infectious agents and scavenge harmful oxygen-free radicals.
7.In addition, beans contain healthy amounts of minerals like iron, calcium, magnesium, manganese, and potassium, which are very essential for body metabolism. Manganese is a co-factor for the antioxidant enzyme, superoxide dismutase, which is a very powerful free radical scavenger. Potassium is an important component of cell and body fluids that helps controlling heart rate and blood pressure.

Other Health Benefits:

The strong carotenoid and flavonoid content of green beans also appears to give this vegetable some potentially unique anti-inflammatory benefits. For example, some very preliminary research in laboratory animals shows decreased activity of certain inflammation-related enzymes—lipoxygenases (LOX) and cyclooxygenases (COX)—following intake of bean extracts. Because type 2 diabetes is a health problem that is known to contain a basic component of chronic, unwanted inflammation, we are also not surprised to see some very preliminary research in the area of green bean intake, anti-inflammatory benefits, and prevention of type 2 diabetes. (The very good fiber content of green beans most likely adds to the potential of green beans to help prevent this common health problem.) We expect to see more research in both of these health benefit areas (anti-inflammatory benefits and prevention of type 2 diabetes).