8 Underrated Vegetables With Huge Health Benefits

(This article previously appeared on Grandparents.com.)

Your parents probably told you the same thing you tell your own family: Eat your vegetables; they're good for you. And there are always certain veggies we focus on — leafy greens such as spinach, broccoli and the like.

But scientific research shows that some veggies that we often write off (celery and mushrooms, anyone?) are actually nutritional all-stars.

Read on to learn about the nutritional power of these seemingly ordinary vegetables — from helping reduce the risk of cancer to boosting your immune system.

One word of caution: The chemical compounds in these natural gems are so potent they can interfere with some prescription drugs. So if you're taking medication, check with your doctor or pharmacist before you add them.

If you associate celery with diets or think the stalks are nothing more than sturdy swizzle sticks for your Bloody Mary, think again. Evidence suggests there's a world of health benefits in every crunch.

Dieters count on celery because it's low in calories — only 10 calories in a large stalk — but also delivers phthalides, which are thought to act as a natural diuretic. Those same phtalides support the circulatory system and can help reduce high blood pressure.

But the best reason to add celery to the grocery list: it just might rev up your sex life.

According to Dr. Alan Hirsch, Director of the Smell and Taste Treatment and Research Foundation, celery contains pheromones, airborne sex chemicals that are released when you chew on a stalk of the green stuff. It's rumored that Casanova ate celery every day to keep his libido strong and if it worked for Casanova, we say pass the crudite.

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One of nature's most powerful tools for fighting breast cancer may already be sitting in your refrigerator.

Mushrooms — from humble, button mushrooms to more exotic shitakes — have been shown to improve the body's immune system and reduce risk of colon, stomach and prostate cancer. In one study, eating mushrooms cut the risk of Chinese women getting breast cancer by 64 percent.

Mushrooms also contain vitamin D and long-chain polysaccharides that can help boost your immune system to help you fight the common cold. To access all the nutritional goodness of mushrooms, be sure to cook them, rather than eat them raw.

The Brussels sprout may be small, but don't be deceived. It's a cancer-fighting Jedi. Brussels sprouts contain more anti-carcinogenic compounds called glucosinolates, than any other cruciferous vegetable. One of these compounds, called sinigrin, causes cancer cells to self-destruct.

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You know that carrots are good for your eyesight. The beta-carotene that makes them orange is converted to vitamin A by your body and that can help protect you from macular degeneration, as well as glaucoma. Eating carrots can even help improve night vision, which is important when driving after dark.

What most of us don't know is that carrots are almost as good for our outsides as they are for our insides.

According to research, carrots contain a powerful antiseptic compound that kills germs and can prevent infection and help wounds to heal more quickly. Shred them raw, cook them and mash them, or soak a cloth in carrot juice and apply it to the affected area.

An NIH study found that peeled, shredded carrots inhibit food spoilage bacteria, which supports the theory that carrots have beneficial antiseptic powers.

If you slice an onion, and it makes you cry, rejoice! Those compounds that are bringing tears to your eyes are called thiosulfinates and they could keep you from having a stroke, according to some studies. Thiosulfinates act as a natural blood thinner and can keep blood platelets from clumping.

In addition, the quercitin in onions has been shown to relax and dilate blood vessels, which also aids in stroke prevention.

Onions are high in vitamin C, provide calcium, iron, folic acid and dietary fiber. And, because they can kill the H pylori bacteria, they may also help to prevent — but not treat — stomach ulcers.

Crunchy, sweet, and delicious, bell peppers are also one of the most healthful foods you can eat. One red bell pepper will provide almost twice your daily allowance for vitamin C. Bell peppers also are an excellent source of vitamin B6, which is used by your body to help regulate metabolism and to enable the cells in your brain to communicate with one another.

Bell peppers also contain minerals, including potassium, zinc, and manganese. According to The Linus Pauling Institute, their high levels of manganese may help to prevent osteoporosis.

Garlic has been credited with warding off everything from vampires to the plague. One whiff, and you know it's powerful. It's antibacterial and antiviral and fresh garlic may help to prevent some cases of food poisoning by killing E coli and salmonella bacteria. Garlic has been credited in studies with lowering blood pressure and cholesterol, protecting the heart, boosting the immune system, and regulating blood sugar levels.

But what really pushed garlic onto our list is that according to research, garlic may help protect against breast, colon and other cancers. And according to research done at the Mayo Clinic, garlic can kill the rogue cells that cause prostate cancer. Maybe that's part of the reason the Mayo Clinic suggests that men with enlarged prostates — which includes 50 percent of men over age 60 — use garlic to season their food.

What provides a daily dose of vitamin A, more vitamin C than an orange, and supports bone health with vitamin K and more calcium than an 8-ounce glass of milk? Kale.

Yes, we all know kale is good for us, but here's what you might not know about this nutritional powerhouse and why it made our list: It's a good source of Omega-3 fatty acids, which means a diet that includes kale will give your brain a boost, helping to fight depression. Those same fatty acids, along with kale's quercetin supply, will fight inflammation and can help to prevent or alleviate arthritis.

If all that good stuff isn't enough to convince you, how about a longer life? Dr. Drew Ramsey, author of 50 Shades of Kale says that the kaemferol in kale literally can turn on the genes that promote longer life.