What are the benefits of raw onion sexually?

If you think of all the aphrodisiac foods out there, raw onion probably isn’t at the top of the list. After all, they’re known to make you cry—not turn you on. However, there is some scientific evidence that suggests there may be benefits of raw onion sexually.

Onions are part of the Allium family, which contains more than 800 species and includes other onion-esque vegetables like garlic, leeks, and shallots. Thought to be one of the first plants to be domesticated over 4,000 years ago, onions have been a dietary staple for a long, long time. The base of many delicious dishes, raw onions also contain essential nutrients important for heart health, disease prevention, and potentially sexual health. 

Read on to learn more about all the benefits this versatile root vegetable has to offer.

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They might make your eyes water, but raw onions are nutritional powerhouses. Onions are a low-calorie food and a healthy source of fiber, protein, and other vitamins and minerals important for overall wellbeing. There are claims that eating onions also has benefits in the bedroom, including:

• Helping with erectile dysfunction (ED)

• Increasing testosterone levels

• Boosting libido (sex drive)

While there’s not much research (on humans, at least) to back these claims up, onions do contain certain micronutrients shown to play a role in sexual function. Of course, resorting to an all-onion diet isn’t going to cure ED or any other sexual problem, but eating nutritious foods—including raw onions—could lower your risk of developing one. Here’s how onions may benefit you sexually. 

May help with erectile dysfunction

Onions for ED have not been widely studied and existing data are limited to animal research, but very early research hints this vegetable has potential. One study found that onion peel and onion root extracts exhibited PDE5 inhibitory activity; PDE5 inhibitors, like Viagra (sildenafil) and Cialis (tadalafil), are a class of medication used to treat ED. PDE5 inhibitors encourage erections by helping blood vessels relax, which encourages more blood flow to the penis. Of course, the PDE5 inhibitory activity of onions is much lower than that of any prescription medication, but it’s still interesting to see that onions may have some effect.

Like other fruits and vegetables, onions also contain antioxidants, which help prevent damage to cells by neutralizing harmful substances in the body. One antioxidant particular to onions is quercetin, which studies have shown plays a role in helping lower inflammation and high blood pressure—both contributors to ED. Though there’s no guarantee that quercetin will help humans get hard (one study observed quercetin improved erectile function in rats), if you have ED caused by blood vessel issues, eating foods that contain heart-healthy antioxidants like quercetin may help.

May improve testosterone levels

Though human studies are limited, there is some evidence that indicates onions can have a positive effect on testosterone levels in men. Testosterone is a sex hormone vital for many bodily processes, including sperm production, sex drive, and erectile function. When testosterone levels drop too low, a condition known as low testosterone or “low T,” it can impact areas of sexual health and potentially contribute to issues like ED and reduced sex drive. 

Again, raw onion isn’t a cure for low T, but studies have shown onion may promote testosterone production by neutralizing harmful substances in the testes (thanks to those antioxidants we mentioned) and increasing the production of luteinizing hormone, which stimulates testosterone production. Onions may also enhance nitric oxide production. Not only does nitric oxide play a role in making testosterone, but it also helps to facilitate erectile function by dilating blood vessels, which encourages blood flow. While onions show promise for promoting testosterone production in numerous animal studies, further research on humans is needed.

May boost sex drive 

For centuries, onions have been used in certain cultures as an aphrodisiac to increase libido. While most of these claims are anecdotal, studies on rats indicate that onions can be an aphrodisiac food that can help boost sex drive. That said, this outcome could be indirect; if onions do improve testosterone production, for people with low T (a symptom of which is low sex drive), balancing out hormone levels is also likely to amp up libido. But again, the studies are on animals—more research on humans is needed.

Another way onions may indirectly improve sex drive is by helping you get a better night’s sleep and potentially decreasing stress. Onions contain cysteine sulfoxides, a type of amino acid that may reduce stress and improve sleep quality. The exact mechanism behind this isn’t known, but a small study observed 30 men and women taking onion extract containing concentrated cysteine sulfoxides had reduced markers of stress and were able to fall asleep more easily. Another study found raw onion juice to be effective for managing insomnia and improving quality of life when coupled with yoga (another healthy living practice good for reducing stress) in 58 adults with insomnia. Lack of sleep is known to cause stress, a known contributor to sexual issues like ED and low sex drive. Onions are also a good source of vitamin B6, which may indirectly improve libido by improving mood and reducing stress.

There might not be enough evidence to confidently say if there are benefits of raw onion sexually, but there certainly are proven perks of the food for other aspects of health. Here are a few more reasons you might want to add more onions to your diet.

Promote heart health

Cardiovascular disease is a leading cause of death worldwide, which is why prevention and managing risk factors are so critical. Heart disease, high blood pressure, and any other sort of issue that impacts blood flow can also lead to ED. While some risk factors (like age and genetics) are out of your control, other factors, like diet, play a huge role in heart health. 

Raw onions contain several compounds that can reduce the risk of cardiovascular disease and generally promote blood vessel health. As mentioned earlier, quercetin may help lower blood pressure in people with hypertension. The sulfur components in raw onions like thiosulfinates and cysteine sulfoxides may cause bad breath, but they may also have the benefit of improving circulation, preventing blood clots from forming, and acting as antioxidants to remove free radicals (unstable molecules) that, in excess, can lead to disease. The bonus of having a healthy heart? It may help with erectile function, especially if you’re dealing with ED caused by blood flow issues.

Keep in mind that not all onions are created equal. While all raw onions contain health-promoting properties, a study of different-colored onion husks showed red and yellow onions contain significantly more antioxidants and beneficial plant chemicals than white onions. Another healthy choice is green onions (“young” onions harvested before the plant reaches maturity), which are chock full of important nutrients like vitamins K and C.

Reduce inflammation

Onions are also known to have anti-inflammatory properties. Inflammation of blood vessels, for example, can damage and stiffen arteries, which may lead to much more serious problems like heart disease. People with ED have also been found to have high levels of inflammation, indicating that chronic inflammation could be a significant risk factor for ED. 

Quercetin and kaempferol (another flavonoid or plant chemical prevalent in onions) specifically have been shown to prevent inflammation. Along with other trace elements like folic acid, magnesium, and potassium that have positive effects on inflammation, onions—specifically red onions—also contain significant amounts of anthocyanin, another flavonoid that may help reduce inflammation. 

May protect against cancer

While cancer doesn’t directly cause ED, there may be a link between the two; according to research, roughly 40% of men who’ve had cancer also experienced ED. Not only can the psychological stress of cancer affect sex drive and erectile function, but treatment options for cancer—including chemotherapy, hormone therapy, radiation, and surgery—can also lead to ED. Unsurprisingly, many prostate cancer survivors have reported ED after undergoing treatment.

More research is needed, but studies suggest that regular intake of onions may lower the risk of brain, breast, liver, lung, and prostate cancer. Of course, onions aren’t guaranteed to prevent the big C and should not be used exclusively to treat cancer. But the biological elements raw onions possess—including quercetin and polyphenols (plant compounds rich in antioxidants)—may have the power to help detoxify and eliminate cancer-causing substances. Other vegetables that can be helpful in cancer prevention include cruciferous vegetables like broccoli, cabbage, and cauliflower.

For most people, onions are safe and healthy to eat. Onion allergies aren’t common, but they can happen. If you experience hives, swelling, rash, trouble breathing, nausea, vomiting, or severe stomach pain after eating or coming into contact with onions, seek medical care immediately. Onions are also toxic to dogs and cats—something to keep in mind if you have any furry friends looking for table scraps.

Food sensitivities to onions are more common side effects as the vegetable contains compounds such as fructans (a type of carbohydrate), which can be difficult to digest. In some people, raw onions may cause bloating, gas, heartburn, and diarrhea. People with irritable bowel syndrome and other gastrointestinal conditions, in particular, may want to avoid onions as they can trigger painful gas and cramping. 

There are many ways to consume raw onions: on sandwiches, in salads, or mixed into salsa or guacamole. They might leave you with a bit of bad breath (like garlic, onions contain sulfur compounds that emit odorous gases that can linger on your breath), but you can also eat raw onions just as they are. Cooked onions generally are easier to digest and may taste better than raw onions, but keep in mind that a significant amount of nutrients may be lost if cooked at a high temperature for a longer time. Interestingly, quickly baking or sauteing onions has actually been found to increase the nutrient profile due to the release of moisture, which can create a more concentrated product. As mentioned, red and yellow onions have much higher nutritional value than white onions. While white onions aren’t likely to hurt you, aiming for a colored variety is better to reap the health benefits.

If you’ve ever chopped a raw onion, you might wonder if the stinging of the eyes and rush of tears is normal. It is, thanks to the sulfurous compounds released during the cutting process. While the stinging can be annoying or uncomfortable, it’s not harmful to your health. Some onions, such as Vidalia onions, have almost no odor. 

There’s not a lot of research on the impact of onions on medication, but the vegetable does contain vitamin K, which may interact with antibiotics, blood thinners, and cholesterol medications. If you’re using any of these medications, it’s a good idea to consult with a healthcare professional to see if onions are safe, especially if they’re new to your diet. 

As you can see, onions can have a whole host of health benefits—including some potential ones for the bedroom. While diet can play a significant role in sexual health and eating nutritiously is linked to a lower risk of ED over time, chowing down on onions every day isn’t a proven treatment for ED or any other sexual dysfunction.

But don’t worry; there are lots of treatments approved by the US Food and Drug Administration that are proven to safely and effectively treat many cases of ED. In fact, the first-line treatment for ED is often FDA-approved prescription medications known as PDE5 inhibitors. These drugs work in part by relaxing blood vessels and increasing blood flow. Here, the most common PDE5 inhibitors used to treat ED: 

• Viagra (sildenafil)

• Cialis (tadalafil)

• Vardenafil (formerly available as brand name Levitra)

• Stendra (avanafil)

While those above are all pills, some PDE5 inhibitors can also be found in different forms. Two examples include:

• Ro’s Daily Rise Gummies: once-daily, fruit-flavored gummies that are made with tadalafil (the active ingredient in Cialis). 

• Ro Sparks: a sublingual (under the tongue) treatment that contains both sildenafil and tadalafil (the active ingredients in Viagra and Cialis, respectively). 

If PDE5 inhibitors aren’t a fit for you, your healthcare provider might bring up other treatment options, such as: 

• Penis pump: a non-surgical device that utilizes suction to increase blood flow to the penis. 

• Injections: a treatment that involves injecting certain medications drugs into a part of the penis that can help with erections

• Penile implant: a surgical procedure that implants a device under the skin of the penis.

How ED is treated very much depends on the cause; for example, treating ED caused by cardiovascular problems may require a different treatment than ED resulting from psychological problems. That’s why it’s so important to speak to a healthcare provider if you’re experiencing symptoms so they can work with you to develop an appropriate treatment plan. 

Lifestyle changes like getting regular exercise, following a nutritious eating pattern, quitting smoking, and reducing stress can also help prevent (and, in some cases, reverse) ED. In addition, if you’ve been prescribed a PDE5 inhibitor for ED, incorporating lifestyle changes into your routine may enhance the effects of the medication.

Onions are a healthy dietary staple available all over the world. Beyond their nutritional value, in some cultures, onions are also considered  to be an aphrodisiac. Despite claims that onions may give you a boost in the bedroom, unfortunately, there’s not enough science to confirm the benefits of raw onion sexually just yet. While onions may not be a proven treatment for ED, here’s why they’re still a great addition to your diet.

• Raw onions are rich in antioxidants and full of essential nutrients that can benefit heart health, cancer prevention, and stress reduction. When picking and choosing what onions to eat, keep in mind that red, green, and yellow onions (especially red ones) have a much higher nutrient profile compared to white onions. Pro tip: The more colorful a fruit or vegetable, the more nutrients it likely has.

• Onions contain compounds like quercetin and cysteine sulfoxides, which may have indirect benefits for sexual health, but there’s no solid evidence supporting onions for treating ED. 

• Early animal studies show promise in the role of onions in encouraging testosterone production, improving erectile function, and even potentially boosting libido. However, larger studies in human populations are needed. 

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How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Editorial Guidelines | Medical Review Process

Current version

March 06, 2025

Written by

Anna Brooks

Fact checked by

Peter Schlegel, MD, FACS and Raagini Yedidi, MD

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About the medical reviewers

Peter Schlegel, MD, FACS

Peter Schlegel, MD, FACS, is a Ro Advisor, board-certified urologist, and internationally acclaimed expert in the treatment of male fertility. For nearly 20 years, Dr. Schlegel served as the chair of Urology at New York Presbyterian/Weill Cornell. He now focuses on providing the best patient care possible for urologic conditions through his private practice.

Raagini Yedidi, MD

Raagini Yedidi, MD, is an internal medicine resident and medical reviewer for Ro.