Onions: Full of Nutrients

These members of the allium genus deliver plenty of health benefits.

By Meredith Stanton
WebMD Weight Loss Clinic - Feature

Reviewed By Kathleen Zelman MPH, RD/LD

Peel away the skin of this vegetable to find whole layers of health benefits. Worshiped by the Egyptians as far back as 3500 B.C., the onion symbolized eternity because of its concentric-circle construction.

Onions are rich in powerful sulfuric compounds, responsible for their pungent odor -- and for irritating our eyes. Studies also suggest that onions may lower high blood pressure, reduce heart attack risk, and even help protect against cancer (probably thanks to the presence of phytochemicals and the flavonoid quercetin).

One large raw onion has only 63 calories, is made up of more than a cup of water, and provides up to 20% of your RDA of vitamin C. Do you tear up when slicing one? Try chilling the onion in the fridge and then delay cutting into the root end of the onion until the rest has been sliced or chopped.

More Health Boosters

Other disease-fighting veggies include garlic, shallots, chives, and leeks -- all members of the same onion genus, allium.

Recipe

Makes 8 servings

5 medium red onions
2 tbsp balsamic vinegar
2 tbsp olive oil
1 tsp kosher salt
1/4-1/2 tsp black pepper
2 lbs green beans or French green beans, trimmed