Onion Juice for Hair Growth: Does It Work?

There are lots of crazy hair growth trends and rumors on the internet (and we mean a lot). Have you heard the one about onion juice for hair growth?

It’s not the start of a bad joke. Many wellness enthusiasts believe onion juice helps with hair growth — some even say it’s a natural alternative to hair loss medication. With as many as 50 percent of men experiencing hair loss by age 50, it’s no surprise that people would look all over for a cure for baldness, including in the produce aisle.

Here, we’ll explain what the science says about onion benefits for hair, how to make DIY onion water for hair (if that’s your thing), plus other proven ways to treat hair loss and encourage hair regrowth.

We’ll cut to the chase: Although these bulb vegetables are rumored to be a popular hair treatment to decrease breakage and increase growth, there’s not much evidence that onions for hair growth are effective.

That said, onions do have a diverse range of health-related benefits.

For example, they’re rich in dietary flavonoids — a group of antioxidants that may be related to a reduced risk of disease. Onions also contain high amounts of dietary fiber, sulfur content, and vitamins, such as vitamin C and essential B vitamins.

But could topical onion juice really help with hair growth?

Well, maybe.

Research on Onion Benefits for Hair

Is there anything to onion juice for hair growth? A review of a 2002 study looked at the effects of onion juice applied twice a day. It showed signs of hair regrowth in almost 87 percent of people after eight weeks.

However, this was a very small study involving less than 50 male and female participants who were dealing with a different type of hair loss than genetic thinning called alopecia areata (which is autoimmune).

So even if onion juice is effective for regrowing hair lost due to alopecia areata, this doesn’t mean it’s a good treatment for male pattern baldness.

The only way for onion juice to help male pattern baldness would be if it contained some sort of compound that addressed the genetic causes of hair loss. Allow us to explain.

• While diet can affect hair health, male pattern baldness — or androgenetic alopecia — is caused by a genetic sensitivity to the hormone dihydrotestosterone (DHT).

• DHT is a byproduct of testosterone — a critical male sex hormone the body produces to develop male characteristics. Your body converts a small amount of testosterone into DHT via an enzyme called 5 alpha-reductase.

• The excess DHT your body makes binds to hair follicles and causes signs of balding, such as thinning hair or a receding hairline (when the hairline makes an M shape).

Since DHT is the primary hormone responsible for male pattern baldness, the most effective hair loss treatments generally work by blocking the effects of DHT. This is what the popular medication finasteride (the active ingredient in Propecia®) does.

Other hair loss treatments increase blood circulation to hair follicles to boost hair growth. This is how onion juice for hair growth is thought to work — that is, if it works.

Onion Juice Effects on Scalp Health

A flavonoid in onions known as quercetin is thought to increase blood flow, which is vital to scalp health. In fact, one of the most popular hair loss medications, minoxidil, is thought to dilate blood vessels, bringing blood flow to the scalp.

So, let’s peel back the layers here (sorry, we’ll stop). Does onion juice stop hair loss caused by male pattern baldness? Unfortunately, probably not.

Despite its potential effect on blood flow, onion juice doesn’t affect hormones, including DHT, so it’s not a miracle solution to male pattern hair loss.

But, theoretically, it could support healthy hair growth or prevent hair fall by boosting blood circulation in the scalp.

Despite the lack of evidence behind the benefits of onions for hair growth, could there be other benefits for healthy hair?

Some research shows that onions have anti-inflammatory properties and antibacterial properties, which could, in theory, help with overall scalp health — especially when it comes to fungus, a characteristic of certain scalp conditions like tinea capitis or dandruff. But this research only looked at onion juice effects on foot fungus.

There aren’t any direct studies on the effects of using onion juice on dandruff or other fungal scalp infections.

As mentioned, onions are high in sulfur. Sulfur is responsible for that funky onion smell and the fact that it makes you cry, but it may have some benefits for hair.

Sulfur is a component of amino acids, the building blocks of keratin. And keratin is an essential protein that gives hair structure. There haven’t been many studies on the link, but hypothetically, onion juice could help strengthen hair.

Using onion juice on hair probably won’t do any harm or cause serious side effects (if you can stand the smell). So you may decide it’s worth a shot.

If you want to give it a try, we’ll go over how to use onion juice for hair, from making it to applying it.

How to Make Onion Juice for Hair

Here’s a step-by-step guide on how to make onion juice for hair:

• Pick out an onion. What’s the best onion for hair growth? You can use any color, but research shows red onions are particularly high in antioxidants. Yellow onions have higher levels of sulfur.

• Wash the onion well, then dry it with a clean towel.

• Cut the onion into chunks or small pieces.

• Add the pieces to a blender or food processor, working in small batches as needed.

• Blend the onion until it has a near-liquid consistency.

• Use a cheesecloth or a very fine strainer to separate the onion juice from the pulp.

• Use the juice immediately or store it in an airtight container for up to three days.

How to Apply Onion Juice for Hair

It’s not every day you apply the juice of an onion to your hair, so you may need a little guidance.

Here’s how to use onion juice on your scalp and hair strands in a way that also helps dilute the smell:

• Combine as much onion juice as you need to cover your scalp (usually three to four teaspoons) with two teaspoons of lemon juice. You can omit the lemon juice, but the onion juice alone will have more odor.

• If you have sensitive skin or have reacted to skincare products in the past, consider doing a patch test of the mixture before applying it to your scalp.

• Apply the concoction to your hair roots and scalp. You can use a cotton pad to dab it on.

• Leave it on for a half-hour like a hair mask. It might help to cover your scalp with a shower cap.

• Wash it out with shampoo. You may need to double-rinse to get the onion smell off your hair.

Unfortunately, there isn’t enough evidence to support using onion water for hair growth. However, many scientifically proven treatments for reducing hair fall and ways to encourage healthy hair growth exist.

• Oral finasteride. An FDA-approved medication for male pattern baldness, finasteride works by inhibiting the effects of 5 alpha-reductase — the enzyme that converts testosterone into DHT. We offer finasteride online following a consultation with a healthcare provider who can determine if a prescription is appropriate.

• Topical minoxidil. The FDA has approved minoxidil as a topical treatment for hair loss and hair regrowth. It comes as minoxidil foam or a liquid solution and is designed to be applied to the areas of the scalp affected by hair loss. Like finasteride, minoxidil has been proven effective in numerous studies, with results usually taking three to six months to appear.

• Topical finasteride & minoxidil spray. A two-in-one combination of finasteride and minoxidil, our topical finasteride & minoxidil spray is a no-pill option for treating hair loss and encouraging regrowth. Preliminary studies on topical finasteride showed a significant decrease in the rate of hair loss and an increase in hair growth.

• Dandruff shampoo. If you struggle with dandruff in addition to hair loss and have thought about using onion juice for its antifungal properties, a dandruff detox shampoo is a surer bet. Ketoconazole shampoo, a mild hair wash with antifungal properties, may also help improve hair growth and stop hair loss.

If you’re looking for more methods to encourage hair regrowth, these science-backed hair growth tips are for you. You can also read more about the research behind whether hair growth products work.

When exploring natural remedies to promote hair growth, you’ve probably encountered methods involving everything from essential oils, castor oil, and coconut oil to apple cider vinegar, aloe vera, and lemon juice.

In your search, the idea of adding onion juice or water to your hair care routine may have caught your attention. But does onion help with hair loss?

Here’s what to keep in mind about onion juice for hair growth:

• There just aren’t enough studies on the effects of onions on hair to say whether they promote hair growth or help with hair thinning. But if you want to try the home remedy, by all means, go for it.

• There’s also no evidence that using onions on your scalp is unsafe or causes hair loss.

• While they’re full of nutrients and vitamins with antioxidant and antifungal properties, onions aren’t a proven-effective hair loss treatment. 

• However, there are other effective treatments for hair loss, such as oral finasteride medication, topical minoxidil solution, two-in-one finasteride and minoxidil spray, and dandruff shampoo.

Learn more about other health benefits of onions for men. You can also connect with a licensed dermatology specialist or healthcare provider to explore more hair loss treatments.