Also well-known as bulb onions or common onions, they space grown global and very closely related come chives, garlic, scallions, shallots, and leeks.

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Onions may have several health benefits, mostly as result of their high content of antioxidants and also sulfur-containing compounds.

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

Commonly offered as a flavoring or next dish, onions are a staple food in many cuisines. They deserve to be baked, boiled, grilled, fried, roasted, sautéed, powdered, or consumed raw.

Onions differ in size, shape, and color, yet the many common species are white, yellow, and red. The taste varieties from mild and also sweet come sharp and spicy, depending upon the variety and season.

Onions can also be consumed as soon as immature, before the bulb reaches full size. They room then referred to as scallions, feather onions, or summer onions.

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

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

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

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

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


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

They consist mostly of an easy sugars, such as glucose, fructose, and also sucrose, and also fiber.

A 3.5-ounce (100-gram) portion contains 9.3 grams that carbs and also 1.7 grams the fiber, for this reason the complete digestible carbohydrate content is 7.6 grams.


Onions are a decent source of fiber, i m sorry accounts for 0.9–2.6% the the new weight, relying on the kind of onion.

They are an extremely rich in healthy and balanced soluble fibers dubbed fructans. In fact, onions are amongst the main dietary sources of fructans (2, 3).

Fructans are so-called prebiotic fibers, which feed the beneficial bacteria in your gut.

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

However, fructans are taken into consideration FODMAPs, which may cause unpleasant digestive symptom in sensitive individuals, such as those v irritable bowel syndrome (IBS) (7, 8, 9).


Onions consist greatly of water, carbs, and fiber. Their main fibers, fructans, deserve to feed the friendly bacteria in her gut, though they may reason digestive troubles in some people.

The health and wellness benefits of onions space attributed to their antioxidants and also sulfur-containing link (3).

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

The many abundant plant compounds in onions are:

Anthocyanins. Only found in red or violet onions, anthocyanins are an effective antioxidants and pigments that provide these onions your reddish color.

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

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


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

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

Blood sugar regulation

Type 2 diabetes is a usual disease, defined primarily through high blood street levels.

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

The exact same results have been presented in humans. One examine in world with kind 2 diabetes uncovered that eating 3.5 ounces (100 grams) of raw onions per day caused a far-ranging reduction in blood street levels (34).

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

Bone health

Osteoporosis is a common health problem, especially in postmenopausal women. A healthy and balanced diet is among the main preventive actions (37, 38).

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

A large observational examine in women over 50 year of age uncovered that consistent onion usage is connected to enhanced bone density (42).

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

Reduction of cancer risk

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

Observational studies have connected increased consumption of onions to a diminished risk the several species of cancers, such as those of 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 sugar levels, boost bone health, and also reduce the risk of several species of cancers.

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

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

Onion intolerance and also allergy

Onion allergy is relatively rare, yet intolerance to raw arrays is reasonably common.

Symptoms that onion intolerance include digestive disruption, such as upset stomach, heartburn, and gas (50).

Some human being may suffer allergic reaction from emotional onions, whether or no they’re allergy to eat them (51).


Onions contain FODMAPs, which room a category of carbs and fibers the many civilization cannot pardon (9, 52, 53).

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

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

Eye and also mouth irritation

The most common issue through preparing and also cutting onions is eye irritation and tear production. When cut, an onion’s cell to relax a gas called lachrymatory variable (LF) (54).

The gas activates neurons in your eyes that reason a stinging sensation, complied with by tears that are developed to flush the end the irritant.

Leaving the root finish intact when cutting might reduce irritation, together the onion base has a greater concentration of these substances 보다 the bulb.

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

LF is additionally responsible because that the burn sensation in your mouth when onions are consumed raw. This burn sensation is lessened or eliminated by food preparation (55).

Dangerous because that pets

While onions room a healthy and balanced component of human diets, they deserve to be fatal for some animals, consisting of dogs, cats, horses, and also monkeys (56).

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

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

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