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Side Effects of Onion Juice on Hair & Growth

Let’s talk about side effects of onion juice on hair...

...and I want you pay attention. Because...

...hair loss is a devastating experience that can lead us to try a bevy of manufactured and alternative natural remedies.

At the end of the day, we are just searching for that special hair growth potion or health-boosting lotion that will help to stimulate our follicles and produce a healthy grade of hair.

Unfortunately, not every natural hair growth remedy delivers results without some form of unanticipated side effects.

Onion juice use for hair loss has been trending for years in the natural hair community. Many naturalistas are often on the hunt for the perfect product to use on their scalp or hair that hasn’t been chemically altered.

Thus, when they hear or read about a natural remedy that promises to produce outstanding results, they sometimes jump in without doing the investigative work to determine if these natural remedies might trigger some unwanted side effects.

FOMO, or the fear of missing out, gets us all in trouble at some point, but there are times when we must slow down to weigh the risks of daring to expose our skin, hair, and scalp to some home treatments.

What are the Side Effects of Onion Juice on Hair?

side effects of onion juice on hair?Are there side effects of onion juice on hair?

Answer: Side effects aside, using onion juice for hair is mostly safe.

Still, side effects from onion juice on hair and scalp can cause irritation and flaking if you have an allergy to onions.

If this is the case you shouldn't use onion juice on your hair. Even among those who are not allergic, onions can be quite caustic to the skin.

Side effects may include redness and itching, depending on how potent a concoction you make for your hair.

So let’s break down some of the details and highlight the side effect of onion juice on hair.

Because, even though onion juice users may boast about remarkable outcomes in using this home remedy, it is known to have a few side effects that you need to know about before choosing to overindulge in this hair growth recipe and application process.

Dry Scalp: Side Effect of Onion Juice on Hair

One of the side effects of onion juice on hair is that it may cause dry scalp.

Although the sulfur ingredient in onion juice may support healthy growth, it can wreak havoc on your scalp, robbing it of moisture and viral nutrients that enable it to serve as a healthy base for sustainable hair growth.

You should never sleep with onion juice on your hair or scalp, as this can sometimes lead to an adverse reaction.

Onion Juice & Hair Loss Side Effects [Despite Hair Growth Success for Some] 

Yeah, I know… The accounts of onion juice hair growth success are out there and they are true.

In the very NHP tutorial I’ll talk to you about a clinical study that proves onion juice hair growth success, especially for men.

Onion Juice contains sulfur, which may contribute to the growth of fabulous thick hair. It is an old Indian tradition used to reduce hair loss and stimulate follicles to produce hair.

In addition to supporting hair growth, onion juice is a hair growth food that has also been used for centuries to slow down the process of premature graying hair, treat scalp infections, improve blood flow to the scalp, and provide relief to those dealing with dandruff.


If you’re sensitive to onion juice, hair loss is another side effect of applying onion juice to your hair and scalp.

The thought of this remedy inducing more hair fall may seem crazy, but it is another side effect to keep an eye out for should you elect to adopt this hair care practice.

Onion juice’s sulfur content can irritate the scalp, leading to dryness and itchiness.

The incessant need to relieve the itch by scratching your scalp can weaken your hair at the root, causing additional hair fall.

If your roots become inflamed due to the scratching or sulfur ingredient, the result can have a detrimental effect on your hair follicles, shrinking them and ultimately disrupting the hair growth cycle.

side effects of onion juice on hair nhp

Itchy Scalp: Side Effect Disadvantages Of Onion Juice For Hair 

Onion juice contains a considerable amount of sulfur, this serves as both an advantageous benefit AND one of the disadvantages of onion juice for hair.

High levels of sulfur can irritate the scalp, leading to episodes of dealing with an itchy scalp. This side effect of onion juice on hair frequently occurs due to one’s failure to thoroughly rinse this solution from their scalp.

Should you choose to use onion juice on your hair and scalp, you will want to take the time to thoroughly rinse your scalp and hair to reduce the risk of overexposure.

[RELATED ARTICLE: Can Greek Dairy help grow longer hair?]

Stank Smell: Side Effect of Onion Juice on Hair

Another one of the side effects of using onion juice on your hair is the smell. There’s no need to worry. The scent is not permanent.

However, you will likely want to follow the onion juice application process with lemon juice and a gentle shampoo that helps to remove the smell.

Hair Growth: Use Onion Juice For Hair How Many Days?

Researchers found that hair growth from days of using onion juice started after 2 weeks, which was applied to the scalp twice daily.

Nearly 74 percent of participants had some hair regrowth after 4 weeks, and at 6 weeks about 87 percent experienced hair regrowth from the onion juice.

Both men and women participated in the study about onion juice for hair and how many days it takes to work. Ultimately, the hair regrowth was higher among the men.

So if you were asking the question, “Can I use onion juice on hair daily?”...

Answer is: Yes, you can if your scalp isn’t sensitive to the sulfur content. As shown in the study above, hair growth success came with MORE than once daily use, but twice a day!

[RELATED ARTICLE: Boost hair growth with celery juice...]

NHP Wrap Up: Side Effects of Onion Juice on Hair

Despite the side effects of onion juice on hair, when used appropriately and with caution onion juice can be highly beneficial for you if you are dealing with hair loss.

Though it may not reverse some instances of balding, it can have a powerful effect on stimulating active hair follicles to produce thick, healthy hair and repair the scalp to a state of high performance.

Should you choose to indulge in the benefits of using onion juice on your hair, always take steps to remove this juice from your scalp and hair.

Always perform a patch test before using onion juice on your hair.

Some people are known to have allergic reactions to using onions on their skin or hair. If you experience irritation, inflammation, itching, or any of the side effects of onion juice on hair you should likely avoid continued use of the DIY hair growth remedy. 

At the end of the day hair and scalp health lead to faster hair growth, we have plenty of hair growth alternative for you to look into, such as hair growth vitamins or the best veggies & foods for hair growth.

Follow Author of Side Effects of Onion Juice on Hair Tutorial... 


Melissa Lee is a Contributing Editor to NHP and a former owner of the BlackhairOMG website. She formed 4C Trichology Growth Services, LLC., a US based hair care consultation service. She has also contributed as a writer and consultant for various hair and beauty websites. Melissa can be followed on Twitter here.

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