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6 Potential Health Benefits of Onions

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health benefits of onions

Since onions can be found almost in every kitchen, you may perceive them as normal vegetables used in various dishes. However, being aware of the health benefits of onions can make you see these vegetables in a new light.

If you, by any chance, know the health benefits of garlic, it can give you a clue about how healthy onions can be. Because onions and garlic come from the same family namely the allium genus.

It appears making the eyes watery and causing bad breath are two main drawbacks of onions. Apart from these small downsides, onions can definitely improve your health in many ways. 

In fact, we (modern people) are not the first ones that consume onions for health purposes. Many ancient civilisations were aware of onions’ healing properties and used onions to treat various ailments. Historical records say that onions have been used for medicinal purposes for more than 4000 years.

Before we dive into the impressive health benefits of onions, let’s glance at the onion’s rich nutrient content which is the main reason why onions are one of the healthiest foods on earth.

Nutritional Value of Onions

There is no doubt that onions are packed with nutrients that are essential for the human body. Onions of all colours are rich in vitamins, minerals and fibre.

In particular, they are rich in vitamin C, vitamin B-6, folate and potassium.

If you are concerned about the calorie count, rest assured that onions are quite low in calories.1 Cup (160 grams) of chopped onion contains 64 calories.

According to the Nutrition Value: a serving size of 100 gr onion provides;

♠ Total Carbohydrate: 9.3 g

♣ Sodium: 4 mg

♠ Dietary Fibre:  1.7 g

♣ Calcium: 23 mg

♠ Potassium                  : 146 mg

♣ Iron: 0.21 mg


Health Benefits of Onions

We compiled 6 impressive health benefits of onions for you, and, supported these health benefits with related scientific studies and experts’ views.


1- May Improve Cardiovascular Health

Directly or indirectly!! The result is onions are good for your heart health.

They may not improve your heart health instantly with a magic wand, nevertheless, onions can significantly reduce your risk of developing heart disease by regulating both high cholesterol and high blood pressure levels, both of which are strong risk factors for coronary heart disease. 

We know from scientific studies that dietary flavonoids have blood pressure-reducing properties. One study about the “efficacy of flavonoids in the management of high blood pressure” proved the efficacy of flavonoids in decreasing blood pressure levels. 

Let’s not forget that onions are one of the richest sources of flavonoids.

The health benefits of onions are not limited to decreasing high blood pressure. As mentioned above, they are also effective in regulating cholesterol levels.

There are scientific studies that support onions’ ability to decrease LDL “bad cholesterol” levels, which is another strong risk factor for heart disease.

In a scientific report published by Cambridge University Press; researchers concluded that quercetin ( found in onions too ) decreases ” bad cholesterol” levels in the arteries.


2- May Reduce Cancer Risk

The main reason onion is associated with decreased risk of cancer stems from the compounds that abound in onions. These compounds have been proven to have cancer-fighting properties.

One of these effective compounds that show a protective effect against different types of cancer is sulphur-containing compounds. As indicated in a well-rounded study; sulfur-containing phytochemicals may have anticancer properties.

In another study, researchers suggested that quercetin, highly available in onions, may stop tumour growth.

Even though there are studies that suggest onions’ potential anti-cancer properties, doctors and scientists underline the fact that there is no food on earth that can bring the risk of cancer to zero alone.


3- Help Regulate Blood Sugar

Since there is no exact cure for diabetes, people with diabetes have to manage their blood sugar levels with different treatment methods. One of the most effective treatments for diabetes is to consume the right foods, say medical experts.

Based on the findings of a study; it is safe to say that onions are effective in regulating blood sugar levels. 

Researchers attribute onions’ potential blood sugar-lowering effect to their both sulfur compounds and flavonoid content.

Consider adding onions to your dishes or consume them raw, but either way, eat them moderately. They can help you manage your blood sugar level. 


4- May Improve Skin

While highlighting the nutritional value of onions earlier in this article, we underlined onions’ relatively high vitamin C content.

Considering vitamin c is one of the most essential nutrients for skin health along with vitamin D, we can infer that onions are beneficial food for the skin.

With its high vitamin C content, onions contribute to collagen production, which is the major component of the skin.

Furthermore, the antioxidants, available in onions will combat free radicals that can bring nothing but harm to your skin.

As they boost skin quality, onions are used as an ingredient in more and more cosmetic products.


5- Help Boost Immunity

In a sense, the strength of your immune system determines how healthy you are. Because this mechanism defends your body against harmful substances and germs like bacteria and viruses.

According to experts; sleep, stress reduction, physical activity and a well-planned diet is indispensable for a healthy immune system. 

Onions can be a sensible food choice if you intend to boost your immune system, although, experts claim that garlic is slightly more effective than onions when it comes to improving the immune system. 

In a report, experts state that nutrients available in onions help the immune system fend off viruses and bacteria. 

Particularly, vitamin C boosts your immune system. Therefore, try to consume onions regularly in moderation.


6- Beneficial For Bones

After a certain age, bones start losing strength and density, therefore, individuals become susceptible to certain bone problems such as osteoporosis and fractures.

To avoid these potential bone problems, experts emphasise the importance of physical activity and diet.

While dairy foods are the first to come to mind owing to their high calcium content, onions, too, can contribute to bone health by decreasing the risk of bone loss thanks to their rich antioxidant content.

In a study, researchers revealed that people who consumed onions once a day had 5 % more bone density than those, who consumed once a month or less.

The conclusion is regular onion intake may support your bone density.


Tarkan is an experienced health writer ( currently more than 600 articles ) and also the founder of this website namely His expertise in health stems from in-depth medical research and knowledge which he obtained over the course of many years.

Tarkan enjoys sharing factual knowledge on health, psychology and nutrition. He always aims to deliver evidence-based recommendations, provide links to related scientific studies.

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