French Green Beans: Vegetable and Legume Benefits in One Food

Like all green beans, the French green bean is an immature fruit enclosed within edible pods. It belongs to the widely populated genus and species Phaseolus vulgaris. This vegetable has a more tender, thinner, and longer pod than other green bean varieties. French green beans come in several types and colors of green, purple, and yellow. The French bean is related to popular green bean cultivars such as Blue Lake, Kentucky Wonder, Tendergreen, and yellow wax beans, as well as bean varieties grown for their seeds: black, kidney, navy, and pinto beans. This makes the French green bean a leguminous vegetable which can provide a singular combination of nutrients to your diet.

Historians believe predecessors of the French bean originated in South America and Central America. In the late 1500s, the Spanish Conquistadors brought them to Europe. The French eventually made this variety popular with the name haricot verts (French for "green bean). Huguenot refugees probably carried them into England during Elizabeth I's reign.

French green beans contain polyphenols with powerful antioxidant properties that can help mitigate the impact of oxidative stress-related and degenerative diseases. The polyphenolic substances fight free radicals in the body, help filter harmful UV radiation, and help curb the effects of aging and macular degeneration. Chinese research notes the beans have antitumor and antifungal properties, as well.

French green beans are a significant source of dietary fiber, which provides a laxative effect, cleaning out and protecting the colon by binding to cancer-causing toxins in the gut. The beans also act as a mild diuretic, promoting the normal flow of waste and eliminating toxins from the body.

French green beans are a trove of trace minerals like calcium, iron, potassium, magnesium, and manganese. These nutrients are integral to many physiological functions including the regulation of blood pressure and heart rate. The plant's antioxidant, anti-inflammatory, and anti-carcinogenic benefits help protect and strengthen the cardiovascular system. Fiber helps inhibit reabsorption of cholesterol-binding bile acids, thus reducing cholesterol levels in the blood.

The human immunodeficiency virus (HIV) attacks the body's ability to fight infection and is incurable. In 2010, researchers in Hong Kong discovered a nutrient in French green beans helps slow the spread of HIV. The vegetable's seeds contain a high yield of hemagglutinin that inhibits the reproduction of HIV-1 cells, the most common form of HIV. The Hong Kong study found French green beans have 10 to 85 times more hemagglutinin than other beans.

Recent research indicates green beans could reduce the risk of developing chronic diseases like type 2 diabetes. As a leguminous vegetable, French beans provide the nutrition normally attributed to legumes without the dense carbohydrate load. The fiber assists in balancing blood glucose levels by slowing down the metabolism of carbohydrates.

Since French green beans are available year round, you may find fresh ones in the produce section of your local grocery store or farmer's market. Look for firm, verdant pods; avoid shriveled, spotted, or tough ones that may be too mature. Place beans in a plastic bag and refrigerate for up to two weeks. For convenience, you may want to purchase canned or frozen French beans, which still contain most of their nutrients. Prepare fresh beans for freezing by washing them, trimming the ends, and removing stringy fibers. If desired, slice beans into bite-size pieces. Blanch for two to three minutes. Cool and place in freezer-safe bags; freeze for up to 10 months. French beans can be canned or quick-pickled, too.

Fresh French green beans are delicious raw, steamed, sauteed, grilled, or roasted. First, rinse them thoroughly under cool water. Trim the stem ends and remove any stringy fibers. Cook them to al dente to retain as much of the nutrient content, flavor, and color as possible. Use your favorite heart-healthy oil, broth, or water along with herbs and spices, to taste. Boiling French green beans causes leaching of much of their nutrients into the water, so it is best to avoid this method.

French green beans are immensely healthy; however, consuming them in large amounts may present an issue for some individuals. The beans contain oxalic acid, which can produce stones in the urinary tract. Lower your risk of this side effect by drinking plenty of water and seeking medical advice if you have had oxalate stones in the past. Also, fresh French beans contain phytic acid, which can inhibit mineral absorption. People at risk of mineral deficiency should limit or avoid raw green beans, though cooking them greatly reduces phytic acid levels. Avoid French green beans if you are allergic to legumes.