Also well-known as bulb onions or common onions, they are grown worldwide and also closely concerned chives, garlic, scallions, shallots, and leeks.

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Onions may have numerous wellness benefits, greatly due to their high content of antioxidants and also sulfur-containing compounds.

They have actually antioxidant and anti-inflammatory impacts and have been linked to a lessened hazard of cancer, lower blood sugar levels, and also boosted bone health and wellness.

Commjust provided as a flavoring or side dish, onions are a staple food in many kind of cuisines. They deserve to be baked, boiled, grilled, fried, roasted, sautéed, powdered, or consumed raw.

Onions vary in dimension, form, and color, yet the many widespread types are white, yellow, and also red. The taste varieties from mild and sweet to sharp and also spicy, depending on the array and also seaboy.

Onions have the right to also be consumed when immature, prior to the bulb reaches full dimension. They are then dubbed scallions, spring onions, or summer onions.

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

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Raw onions are very low in calories, via only 40 calories per 3.5 ounces (100 grams).

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

The main 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


Carbohydprices consist of around 9–10% of both raw and also cooked onions.

They consist largely of basic sugars, such as glucose, fructose, and also sucrose, and also fiber.

A 3.5-ounce (100-gram) percentage has 9.3 grams of carbs and also 1.7 grams of fiber, so the complete digestible carb content is 7.6 grams.


Onions are a decent source of fiber, which accounts for 0.9–2.6% of the fresh weight, relying on the form of onion.

They are exceptionally well-off in healthy soluble fibers called fructans. In truth, onions are among the primary dietary sources of fructans (2, 3).

Fructans are so-referred to as prebiotic fibers, which feed the useful bacteria in your gut.

This leads to the formation of short-chain fatty acids (SCFAs), such as butyrate, which might enhance colon health, alleviate inflammation, and reduced your hazard of colon cancer (4, 5, 6).

However before, fructans are thought about FODMAPs, which may reason unpleasant digestive symptoms in sensitive individuals, such as those through irritable bowel syndrome (IBS) (7, 8, 9).


Onions consist mainly of water, carbs, and also fiber. Their primary fibers, fructans, have the right to feed the friendly bacteria in your gut, though they may cause digestive difficulties in some people.

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

In many nations, onions are additionally among the main dietary resources of flavonoids, particularly a compound dubbed quercetin (16, 17, 18).

The the majority of numerous plant compounds in onions are:

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

Red and yellow onions are richer in antioxidants than other forms. In fact, yellow onions may contain practically 11 times even more antioxidants than white onions (25).

Cooking deserve to significantly mitigate levels of some antioxidants (26).


Onions are well-off in plant compounds and antioxidants, specifically quercetin and sulfur-containing compounds. Colorful varieties, such as yellow or red ones, pack even more antioxidants than white ones.

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

Blood sugar regulation

Type 2 diabetes is a common illness, characterized mainly by high blood sugar levels.

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

The very same outcomes have been displayed in human beings. One examine in world via kind 2 diabetes uncovered that eating 3.5 ounces (100 grams) of raw onions per day resulted in a far-reaching reduction in blood sugar levels (34).

Raw onions might aid manage both type 1 and also 2 diabetes, but even more research study is essential (35, 36).

Bone health

Osteoporosis is a common health trouble, specifically in postmenopausal women. A healthy diet is just one of the main preventive procedures (37, 38).

Animal studies disclose that onions defend against bone degradation and also may also boost bone mass (39, 40, 41).

A big observational study in woguys over 50 years of age found that continuous onion usage is linked to raised bone density (42).

More research indicates that intake of selected fruit, herbs, and vegetables, including onions, might reduce bone loss in postmenopausal woguys (43).

Reduction of cancer risk

Cancer is a widespread illness, characterized by unregulated cell expansion. It is among the world’s leading reasons of death.

Observational researches have actually attached increased intake of onions to a decreased threat of a number of forms of cancers, such as those of the stomach, breastern, colon, and also prostate (44, 45, 46, 47, 48, 49).


Onions have antioxidant and also anti-inflammatory impacts. They might reduced blood sugar levels, boost bone health, and also alleviate the risk of several types of cancers.

Eating onions can bring about poor breath and also an unpleasant body odor.

Several various other downsides might make this vegetable unsuitable for some world.

Onion intolerance and allergy

Onion allergy is relatively rare, yet intolerance to raw varieties is sensibly prevalent.

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

Some human being may suffer allergic reactions from touching onions, whether or not they’re allergic to eating them (51).


Onions contain FODMAPs, which are a category of carbs and also fibers that many human being cannot tolerate (9, 52, 53).

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

Individuals with IBS are regularly intolerant to FODMAPs and also may want to avoid onions.

Eye and mouth irritation

The many common issue with preparing and cutting onions is eye irritation and tear production. When cut, an onion’s cells to release a gas referred to as lachrymatory element (LF) (54).

The gas activates neurons in your eyes that cause a stinging sensation, complied with 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 greater concentration of these substances than the bulb.

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

LF is additionally responsible for the burning sensation in your mouth when onions are eaten raw. This burning sensation is diminished or removed by food preparation (55).

Dangerous for pets

While onions are a healthy and balanced component of humale diets, they have the right to be deadly for some animals, consisting of dogs, cats, horses, and chimpanzees (56).

The main culprits are sulfoxides and sulfides, which can induce an illness referred to as Heinz body anemia. This disease is defined by damages within animals’ red blood cells, which leads to anemia (57).

Make sure not to feed onions to your pet, and save anypoint flavored via onions out of reach if you have an animal in your house.

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Onions might reason adverse digestive results in some human being, and also raw onion deserve to reason eye and mouth irritation. Onions may be toxic to some animals.