Also recognized as bulb onions or usual onions, they are grown an international and closely related come chives, garlic, scallions, shallots, and leeks.

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

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

Commonly provided as a flavoring or next dish, onions are a staple food in countless cuisines. They have the right to be baked, boiled, grilled, fried, roasted, sautéed, powdered, or consumed raw.

Onions vary in size, shape, and also color, but the most common varieties are white, yellow, and red. The taste varieties from mild and sweet come sharp and spicy, depending upon the range and season.

Onions can also be consumed as soon as immature, prior to the pear reaches full size. They space then referred to as scallions, feather onions, or summer onions.

This short article tells you everything you need to know around onions.

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

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

The main nutrients in 3.5 ounces (100 grams) of life onions space (1):

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


Carbohydrates do up around 9–10% of both raw and also cooked onions.

They consist mainly of an easy sugars, such together glucose, fructose, and sucrose, as well as fiber.

A 3.5-ounce (100-gram) part contains 9.3 grams of carbs and 1.7 grams that fiber, therefore the complete digestible carbohydrate content is 7.6 grams.


Onions space a decent resource of fiber, i beg your pardon accounts because that 0.9–2.6% of the new weight, depending upon the type of onion.

They are very 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 feed the beneficial bacteria in her gut.

This leader to the formation of short-chain fat acids (SCFAs), such as butyrate, i m sorry may enhance colon health, mitigate inflammation, and cut your threat of colon cancer (4, 5, 6).

However, fructans are considered FODMAPs, i beg your pardon may reason unpleasant digestive symptoms in sensitive individuals, such together those through irritable bowel syndrome (IBS) (7, 8, 9).


Onions consist greatly of water, carbs, and fiber. Their main fibers, fructans, can feed the friendly bacteria in your gut, despite they may reason digestive problems in some people.

The health and wellness benefits the onions are attributed to their antioxidants and also sulfur-containing compounds (3).

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

The many abundant tree compounds in onions are:

Anthocyanins. Only discovered in red or violet onions, anthocyanins are an effective antioxidants and pigments that offer these onions their reddish color.

Red and yellow onions are richer in antioxidants than other types. In fact, yellow onions may contain virtually 11 times an ext antioxidants than white onions (25).

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


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

Onions have actually been presented to have solid antioxidant and anti-inflammatory properties (3, 28, 29, 30).

Blood street regulation

Type 2 diabetes is a usual disease, characterized primarily through high blood sugar levels.

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

The exact same results have been presented in humans. One research in civilization with form 2 diabetes found that eating 3.5 ounces (100 grams) of life onions per day led to a significant reduction in blood street levels (34).

Raw onions may help control both kind 1 and also 2 diabetes, but more research is needed (35, 36).

Bone health

Osteoporosis is a common health problem, especially in postmenopausal women. A healthy diet is just one of the key preventive actions (37, 38).

Animal studies reveal that onions protect versus bone deterioration and also may also increase bone massive (39, 40, 41).

A huge observational examine in females over 50 year of age found that consistent onion usage is connected to raised bone thickness (42).

Further research suggests that entry of selected fruit, herbs, and also vegetables, consisting of onions, may reduce bone ns in postmenopausal ladies (43).

Reduction the cancer risk

Cancer is a common disease, characterized by untreated cell growth. It is one of the world’s leading reasons of death.

Observational researches have connected increased usage of onions come a decreased risk the several species of cancers, such as those the the stomach, breast, colon, and prostate (44, 45, 46, 47, 48, 49).


Onions have actually antioxidant and also anti-inflammatory effects. Castle may lower blood street levels, boost bone health, and also reduce the risk of several species of cancers.

Eating onions have the right to lead to bad breath and an unpleasant body odor.

Several other downsides might make this vegetable unsuitable for part people.

Onion intolerance and allergy

Onion allergy is fairly rare, but intolerance come raw ranges is fairly common.

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

Some people may endure allergic reactions from touching onions, even if it is or no they’re allergy to eating them (51).


Onions save on computer FODMAPs, which are a classification of carbs and fibers the many civilization cannot pardon (9, 52, 53).

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

Individuals with IBS are frequently intolerant to FODMAPs and may want to protect against onions.

Eye and also mouth irritation

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

The gas activates neurons in your eyes that cause a stinging sensation, followed by tears that are produced to flush the end the irritant.

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

Cutting onions under to run water may additionally prevent this gas from dissolving into the air.

LF is also responsible for the burn sensation in her mouth once onions are eaten raw. This burning sensation is diminished or got rid of by cooking (55).

Dangerous for pets

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

The key culprits space sulfoxides and also sulfides, which can induce a disease called Heinz human body anemia. This condition is characterized by damage within animals’ red blood cells, which leader to anemia (57).

Make certain not to feeding onions to your pet, and keep noþeles flavored v onions out of reach if you have actually an animal in your home.

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Onions may reason adverse digestive effects in some people, and also raw onion can reason eye and also mouth irritation. Onions may be toxicity to some animals.