Raw Onions

Effects of Eating Raw Onions

Raw onions, what are the effects, if any, of eating them? Aside from your breath smelling like onions the rest of the day? Is the onion just a vegetable that adds some flavor to your foods? We know that it is extremely versatile.


It can be eaten raw, fried, sauteed, as an ingredient in casseroles, hotdishes, eggs and many other foods,  and of course as an appetizer.

With all the varieties of onion out there, it is easy to understand that many of us will eat nearly 20 pounds of onion per person yearly. The varieties include red, white, yellow, purple, Vidalia and Spanish onions.

You can purchase onion powder, onion salt, dried onion, onion soup and some specialty stores have onion juice available.

The onion is part of the Allium genus, with garlic, chives, scallions, leeks and shallots.

Nutrient Dense

Raw Onions

Not only are they low in calories, onions are packed with nutrients. It is surprisingly high in Vitamin C, which is great to help the immune system. Vitamin C also acts as an antioxidant to protect your cells from free radicals that will damage cells. There are only 44 calories in a medium sized onion.

Onions are also rich in Vitamin C, including folate and pyridoxine. These help the system with red blood cell production, nerve function and also with your metabolism.

Potassium is one nutrient that most people are low in. Onions have that potassium for your body. Our normal cell function, fluid balance, kidney function, nerve transmission and muscle contraction all require potassium. Most people only intake half the daily amount that they should be taking to allow their functions to work properly.

Heart Health

Onions contain amounts of compounds and antioxidants that help fight inflammation, decrease the triglycerides, and may help to reduce cholesterol. All this is to help you have a healthy working heart.

There is a highly potent anti-inflammatory in onions that may help reduce the risk of heart disease and reduce high blood pressure. This compound is called Quercetin.


Raw Onions

Loaded with antioxidants, these compounds fight oxidation which will lead to cell damage and lead to a risk of cancers, heart disease and diabetes. There are roughly 25 of these antioxidants in onions.

Red onions contain anthocyanins. Many countries have found that people who consume these anthocyanins have a reduced risk of heart disease.

Fighting Cancer

Raw Onions

Eating vegetables from the Allium genus has been shown to lower cancer risk for certain cancers, such as colorectal and stomach cancer.

Blood Sugar Control

There is some information that states eating raw onions can help regulate blood sugar. There are compounds found in onions such as Quercetin and sulfur compounds that are said to help control blood sugar.

Bone Density

Raw Onions

Milk and calcium usually get the benefit of helping bone density, however, onions should be considered in that beneficial list. Studies have shown that in post menopausal women, those who consumed3.4 ounces of onion juice daily over an 8 week period showed improvement in bone mineral density and activity from the antioxidants. This was in comparison to a control group.

Another study showed that women who ate onions at least once a day, had an improved overall bone mineral density versus those who ate onions much less often. The same study showed that women who ate onions frequently had less risk of hip fracture compared to those who never ate onions.

Antibacterial Properties

Raw Onions

Onions are known to fight deadly bacteria such as E Coli.  Quercetin is shown to be a powerful method of fighting bacteria. H-Pylori is a bacteria linked to stomach cancer and other digestive cancers. MRSA is an antibiotic resistant bacteria that causes infections throughout the body. Test tube studies have revealed that quercetin has been known to damage the cells of MRSA as well as the membranes of both MRSA and E Coli.

Digestive Health

Onions are filled with prebiotics and fiber. These work in the digestive tract to promote optimum health. The prebiotics are broken down by gut bacteria that are beneficial. The prebiotics are beneficial due to the non digestible fiber, the bacteria will break down the prebiotics and create the short chain fatty acids.

All the research has shown that these short chain fatty acids boost immunity, promote optimum gut health, enhance digestion and boost the immunity. This research also shows that eating foods rich in prebiotics increases the probiotics to benefit the gut health and digestive tract.

Hair and Skin Benefit

Raw Onions

The Vitamins in onions, including A, C, and K can actually be a benefit to your skin and hair. These Vitamins are known to get rid of pigmentation, protect your skin from the harmful UltraViolet rays and also support building and maintaining collagen. Collagen is what provides structure to your skin and your hair.

Male Sexual Benefits

Onions not only play an important role in helping produce good cholesterol, which helps keep you heart healthy, the onion can also help to improve sexual health and sex drive naturally. Onions are known to be one of the best aphrodisiac foods.

The lowly onion can increase libido and strengthen the reproductive organs. Onions can also increase the testosterone levels in males and help to increase the sexual stamina. As a combination, onion and garlic could be considered to be a sex tonic and  boost your sexual potency.

It has been said that sautéing onions in butter and then mixing them with honey is a great benefit for penile health and is used as an aphrodisiac.


Raw Onions

When onions are eaten at night, before bed, research shows that sleep is better. Onions are rich in L-Tryptophan. This is a natural amino acid that works as a sedative. Vitamin C works as a stress reducer and limits the inner body activity, which is what helps you sleep better. There has been no evidence that Vitamin C can produce better sleep, however.

Negative Effects

Consuming onions can have a negative effect for some people.  Onions have been around for centuries, throughout many generations and have been used as a medicinal herb also. Although filled with so many possible benefit to health, onions may also have a downside.

Aggravating to IBS

Raw Onions

Affecting up to 15% of the world’s population, Irritable Bowel Syndrome can be affected by onions. Treatment for Irritable Bowel Syndrome is many fold. However, although foods are not considered a cause of IBS, certain foods can trigger symptoms. There are some foods that are considered indigestible and are slowly absorbed as short chain carbohydrates.

Onions are part of this list. The medical field will inform patients about FODMAP. This stands for “formidable oligo-, di-, monosaccharides and polyols. It is advised that those affected by IBS avoid foods such as onions, shallots, garlic, wheat and milk products, legumes and coconut. This will prevent the swelling of the intestinal tract. People with IBS should either temporarily or permanently avoid these foods.


Onions are a part of the Liliceae family, along with shallots, garlic and others. Food allergies come from food proteins and can affect your gut, skin, heart, respiratory function and nervous system. Onions contain compounds which can cause allergy symptoms.

Eye Irritant

Raw Onions

Many people who slice and dice onions find that their eyes will tear up and they will have a stinging sensation in the eyes. Onions produce Sulfur Metabolite, this works as a chemical defense against animals and microbes. The best defense to avoid your eyes tearing up is to chill the onion before working with it.


Onions are known to cause heartburn in many people. Heartburn is also considered a symptom of GERD, gastroesophageal reflux disease. Studies and research done in the 1990s and 2000, showed that onions can relax the lower esophageal sphincter. This means that the food will make its way back up or cause severe heartburn.

Drug Interactions

Raw Onions

Onions have a potential anticoagulant effect. This means that they prevent the formation of blood clots. While most of the time this would be considered beneficial, for those who have medications such as Warfarin, this can be an issue and cause serious bleeding.

As a side note, if onions are one of those foods that negatively affect you, try using celery, ginger or radishes to flavor the foods instead.

Ultimately onions are loaded with flavonoids, antioxidants and have an anti-inflammatory effect. They can help strengthen reproductive organs, build collagen for healthy hair and skin, and help protect against dangerous UV rays. Some compounds found in the onions may help ease or reduce the risk of many chronic conditions.

It is also possible that you will show negative effects when eating onions. Whether it is an allergy, increased symptoms of IBS, increased heartburn or severe halitosis.

What is important to remember is that onions are packed with nutrients that are capable of aiding our bodies and the systems to function better. Onions may even help improve your sexual libido and improve your sex drive.

However, onions can also have a negative effect on some medications. One of these being Warfarin. When Warfarin is affected by onions, this could cause severe bleeding issues.