15 Health Benefits Of Onions
The onions are believed to be originated in Central Asia, possibly in the Iran-Pakistan region. Today, they are the most widely cultivated species of the genus Allium.
There are many different varieties of onions, where red, yellow, and white onions are the most popular. Each of this variety has its own unique flavor, from very strong to mildly sweet flavor.
The onions have been used for thousands of years as an ingredient in various dishes by many cultures around the world. These vegetable can be eaten raw, cooked, fried, dried or roasted. They are commonly used as a flavoring and seasoning agent in many dishes.
Apart from adding flavor and taste to dish, onions are known to offer a wide range of health benefits. Onions have been used for centuries to reduce inflammation and heal infections. Even the World Health Organization (WHO) has recognized and confirmed the onion’s ability to relieve cough, congestion, bronchitis and respiratory problems.
Onion Nutrition Facts
Onions are very low in calories and fats, but rich in soluble dietary fiber and are an excellent source of vitamin C, vitamin B6, folate, calcium, iron, and potassium, magnesium and phosphorus.
They also contain flavonoid quercetin and sulfur-containing compounds like sulfides, polysulfides, and thiosulfinates. These sulfur-containing compounds are responsible for its characteristic flavor and eye irritating compounds when the onion is cut.
The flavonoids and sulfur-containing compounds of onion have been shown to have antioxidants, antibacterial, anti-cancer, and anti-inflammatory properties.
Health Benefits of Onions
1. Fight cancer
Onion extract is rich in a variety of sulfides, which provide some protection against tumor growth. Some studies have showed that regular consumption of onions helps to reduce the risk of several cancers such as breast cancer, colorectal cancer, prostate cancer, esophageal cancer, laryngeal cancer, stomach cancer and ovarian cancer [1, 2].
Vitamin C present in onions is also a strong antioxidant that can reduce the presence and impact of free radicals in the body.
2. Reduce blood sugar levels
Raw onions may be beneficial in the treatment of type 2 diabetes. A study found that the sulfur compounds in onions can help to reduce the glucose levels by increasing the amount of insulin, but more research is needed .
3. Prevent cardiovascular disease
Onions are a rich source of flavonoids which provide protection against cardiovascular disease. Onions also contain thiosulfinates that act as natural blood thinners and reduce the risk of heart attack and stroke.
4. Reduce inflammation
Since onions are anti-inflammatory in nature, they can help to reduce inflammation of conditions like arthritis and gout.
According to the Arthritis Foundation, quercetin in onions can inhibit the activity of leukotrienes, prostaglandins, and histamines – all of which cause inflammation – in osteoarthritis and rheumatoid arthritis . Onion intake was also found to help treat joint pain.
5. Enhance immune system
Onions contain selenium that can boost the immune system and fight against all kinds of infections. Moreover, quercetin, a compound in onion also provides strong immunity during an illness such as cold by increasing blood circulation and eliminating various foreign bodies that can lead to diseases and illness.
6. Improve digestive system
Onions are rich in dietary fiber, which is good for maintaining a healthy and regular digestive system. When consumed, this fiber can support the growth of good bacteria in the intestines. It also good in treating diarrhea and constipation, thereby promoting a healthy digestion.
7. Stimulate hair growth
Onion is rich in sulfur which is one of the essential nutrients in promoting hair growth. When applied to the scalp, onion juice provides this extra sulfur for stronger and thicker hair. This sulfur can also stimulate collagen production, which in turn aids in the production of healthy skin cells and stimulate hair growth.
In a 2002 study, participants who washed their hair with onion juice experienced more hair growth than those who washed it with tap water. Men also appeared to experience a greater benefit than women.
8. Treat acne
The antibacterial, antimicrobial, and anti-inflammatory properties of onion are effective in combating acne-causing bacteria which will in turn give you a radiant look. The phytonutrients and vitamins present in onions will also provide nourishment to your skin, reducing spot and pigmentation caused due to acne.
Mix 1 tablespoon of onion juice or extract with 1 tablespoon of olive oil and apply it to your face. Leave it on for about 20 minutes and then wash it off. You can also improve the condition by consuming onions as well.
9. Maintain bone health
Preliminary research suggests that onions can prevent osteoporosis. According to a study from the University of Bern in Switzerland, a peptide compound in onions called GPCS can inhibit loss of bone minerals and calcium, making onions effective against osteoporosis.
Another study revealed that women who ate onions regularly had 5 percent more bone mass than those who ate less. Onion consumption was also found to have a beneficial effect on the bone density of women older than 50 years .
10. Cold and cough reliever
Onion is also a great remedy for cold and flu. This is because they are high in antiviral sulphuric compounds, which are indicated by the strong odor and flavor they release.
If you are suffering from cold and cough, you can simply consume onion juice combined with one tablespoon of honey. This simple mixture can help relieving the pain and discomfort.
11. Promote oral health
The sulfur compounds in onions can help eliminate the bacteria and germs responsible for tooth decay and other teeth related problems.
If you are experiencing from oral infections, chewing on these for two to three minutes will help. Make sure to chew the raw ones for killing all the germs in the mouth.
However, the downside of this that they can cause bad breath. Hence, wash your mouth thoroughly after consuming onions, especially if you are heading to a social gathering.
12. Maintain eye health
The sulfur in onions can also help protect the lens of your eye from cataract formation. It works by stimulating the production of a protein named glutathione, which acts as an antioxidant for the lenses of the eye.
High levels of glutathione in the body appear to protect against eye health issues like glaucoma, cataracts and macular degeneration. Moreover, the selenium in onions helps the body absorb vitamin E, which is critical to healthy vision.
13. Treat urinary disorders
Onion has diuretic properties which have been shown to be useful in treating urinary disorders. That’s why some medical practitioners would advise those suffering from burning sensation during urination to drink water boiled with 6 to 7 grams of onion. This may relieve the symptoms.
14. Fight allergies
Onion is a well-known source of quercetin, a powerful natural anti-histamine. It prevents immune cells from releasing histamines that cause allergic reactions.
Quercetin is such a powerful allergy fighter, in fact, that in one study it actually suppressed the anaphylactic reaction to peanuts in allergic mice. In another study, it outperformed a commercially available drug in suppressing allergic contact dermatitis in humans.
15. Relieve asthma symptoms
If you are suffering from asthma, then red onion may be very beneficial to you. Red onions contain several compounds such as quercetin, anthocyanins, and thiosulfinate, and research has shown that eating them regularly can help soothe the symptoms of asthma.
How to Select and Store Onions
When buying onions, choose the ones that are firm, well shaped, and have no opening at the neck. Fresh onions are usually covered with papery, smooth outer scales. Avoid those with soft, wet necks or bulbs as they are starting to decay.
Onions are best stored at room temperature in a well-ventilated, dry area. Ideally, place them in a wire basket or perforated bowl to allow maximum airflow. This will keep them for months. For partially used onions, wrap them tightly in plastic wrap or in a sealed container, and refrigerate. The onions will keep for several days.
However, onions should never be stored with potatoes, as they will absorb moisture from the potatoes and decay more rapidly.