Also known as bulb onions or typical onions, they are grown an international and very closely related to chives, garlic, scallions, shallots, and leeks.

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Onions may have actually several wellness benefits, mostly due to their high contents of antioxidants and also sulfur-containing compounds.

They have actually antioxidant and anti-inflammatory effects and also have been linked to a lessened risk the cancer, reduced blood sugar levels, and improved bone health.

Commonly supplied as a flavoring or next dish, onions room a clip food in numerous cuisines. They deserve to be baked, boiled, grilled, fried, roasted, sautéed, powdered, or consumed raw.

Onions vary in size, shape, and also color, however the many common types are white, yellow, and red. The taste ranges from mild and sweet to sharp and spicy, depending upon the variety and season.

Onions can likewise be consumed when immature, prior to the bulb reaches full size. They space then dubbed scallions, spring onions, or summer onions.

This article tells you everything you have to know about onions.

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Raw onions are an extremely low in calories, with just 40 calories per 3.5 ounces (100 grams).

By fresh weight, they are 89% water, 9% carbs, and also 1.7% fiber, with tiny amounts of protein and also fat.

The key nutrients in 3.5 ounces (100 grams) of raw onions are (1):

Calories: 40Water: 89%Protein: 1.1 gramsCarbs: 9.3 gramsSugar: 4.2 gramsFiber: 1.7 gramsFat: 0.1 grams


Carbohydrates do up about 9–10% that both raw and cooked onions.

They consist largely of simple sugars, such together glucose, fructose, and also sucrose, and fiber.

A 3.5-ounce (100-gram) part contains 9.3 grams of carbs and 1.7 grams the fiber, for this reason the total digestible carbohydrate content is 7.6 grams.


Onions are a decent resource of fiber, i beg your pardon accounts for 0.9–2.6% that the new weight, relying on the form of onion.

They are really rich in healthy and balanced soluble fibers referred to as fructans. In fact, onions are among the key dietary resources of fructans (2, 3).

Fructans room so-called prebiotic fibers, which feeding the useful bacteria in her gut.

This leader to the development of short-chain fatty acids (SCFAs), such together butyrate, i beg your pardon may boost colon health, alleviate inflammation, and cut your hazard of colon cancer (4, 5, 6).

However, fructans are considered FODMAPs, which may reason unpleasant digestive symptoms in sensitive individuals, such together those v irritable bowel syndrome (IBS) (7, 8, 9).


Onions consist mostly of water, carbs, and fiber. Their key fibers, fructans, have the right to feed the familiar bacteria in her gut, though they may cause digestive difficulties in some people.

The health and wellness benefits of onions room attributed to your antioxidants and sulfur-containing compound (3).

In numerous countries, onions are likewise among the key dietary resources of flavonoids, specifically a compound referred to as quercetin (16, 17, 18).

The many abundant plant compounds in onions are:

Anthocyanins. Only found in red or purple onions, anthocyanins are powerful antioxidants and pigments that give these onions their reddish color.

Red and yellow onions space richer in antioxidant than other types. In fact, yellow onions might contain practically 11 times much more antioxidants than white onions (25).

Cooking can substantially reduce levels of some antioxidants (26).


Onions space rich in plant compounds and antioxidants, particularly quercetin and sulfur-containing compounds. Vibrant varieties, such as yellow or red ones, pack much more antioxidants 보다 white ones.

Onions have actually been presented to have strong antioxidant and also anti-inflammatory nature (3, 28, 29, 30).

Blood sugar regulation

Type 2 diabetes is a usual disease, characterized primarily by high blood street levels.

Animal studies indicate that onions deserve to lower blood sugar levels (31, 32, 33).

The very same results have been presented in humans. One research in civilization with kind 2 diabetes found that eating 3.5 ounces (100 grams) of raw onions every day caused a far-reaching reduction in blood sugar levels (34).

Raw onions may aid control both type 1 and 2 diabetes, but much more research is needed (35, 36).

Bone health

Osteoporosis is a typical health problem, particularly in postmenopausal women. A healthy diet is among the key preventive steps (37, 38).

Animal studies reveal that onions protect against bone deterioration and also may even increase bone mass (39, 40, 41).

A huge observational research in women over 50 year of age uncovered that consistent onion usage is linked to enhanced bone density (42).

Further research shows that input of selected fruit, herbs, and also vegetables, consisting of onions, may reduce bone lose in postmenopausal females (43).

Reduction the cancer risk

Cancer is a usual disease, characterized by untreated cell growth. It is among the world leading reasons of death.

Observational studies have linked increased usage of onions to a lessened risk that several types of cancers, such as those that the stomach, breast, colon, and prostate (44, 45, 46, 47, 48, 49).


Onions have actually antioxidant and also anti-inflammatory effects. They may reduced blood sugar levels, boost bone health, and also reduce the danger of several species of cancers.

Eating onions deserve to lead to poor breath and an unpleasant body odor.

Several other downsides may make this vegetables unsuitable for part people.

Onion intolerance and allergy

Onion allergy is relatively rare, yet intolerance come raw varieties is fairly common.

Symptoms that onion intolerance encompass digestive disruption, such together upset stomach, heartburn, and also gas (50).

Some civilization may endure allergic reaction from emotional onions, whether or not they’re allergic to eating them (51).


Onions save on computer FODMAPs, which space a group of carbs and fibers that many people cannot tolerate (9, 52, 53).

They may cause unpleasant digestive symptoms, such as bloating, gas, cramping, and diarrhea (7, 8).

Individuals v IBS are often intolerant come FODMAPs and may want to avoid onions.

Eye and also mouth irritation

The most usual issue through preparing and cutting onions is eye irritation and also tear production. As soon as cut, one onion’s cell to relax a gas dubbed lachrymatory factor (LF) (54).

The gas activates neurons in her eyes that reason a stinging sensation, followed by tears that are produced to flush out the irritant.

Leaving the root finish intact while cutting may reduce irritation, as the onion base has a higher concentration of these substances than the bulb.

Cutting onions under running water may also prevent this gas from dissolving right into the air.

LF is likewise responsible because that the burn sensation in her mouth once onions are eaten raw. This burning sensation is diminished or removed by cooking (55).

Dangerous for pets

While onions space a healthy component of person diets, they deserve to be deadly for part animals, consisting of dogs, cats, horses, and also monkeys (56).

The key culprits are sulfoxides and also sulfides, which have the right to induce a an illness called Heinz body anemia. This condition is identified by damage within animals’ red blood cells, which leader to anemia (57).

Make sure not to feeding onions to your pet, and also keep anything flavored v onions the end of reach if you have actually an pet in your home.

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Onions may cause adverse digestive results in part people, and also raw onion can reason eye and mouth irritation. Onions might be toxic to part animals.