Does Applying Raw Onion Juice to Your Scalp Really Decrease Hair Loss?
From scalp serums to hair masks and prescription medications, numerous hair loss treatments promise to boost hair growth. But did you know that you might already have a natural remedy for thinning strands right in your kitchen? Believe it or not, onions aren't just an ingredient for tossing into salads and sandwiches. This vegetable—particularly its juice—might actually make hair fuller. Onion juice, especially when made at home, is thought to help decrease hair loss by rejuvenating your scalp cells and hair follicles. While this antioxidant-rich vegetable is already known to support bone health, heart health, and gut health, its benefits can potentially trickle into the beauty space, too.
To get to the bottom of this fascinating method, we asked trichologists and doctors to help us understand exactly how onion juice can impact hair health. For starters, does onion juice really decrease hair loss? The short answer: Yes, it can! As for the long answer: You'll only see potential regrowth after topically applying onion juice to your scalp if your hair loss is caused by a few specific issues. The experts broke it down for us; find their insight and suggestions below.
Why Does Onion Juice Prevent or Decrease Hair Loss?
"Onion juice has the potential to help stimulate hair follicles and thereby encourage hair growth," explains Tiffany Young, a certified trichologist and the CEO and founder of ThinHairThick. "It is also a natural antiseptic. Hair loss that is caused from inflammatory disease, poor blood flow, and poor diet could see a benefit." Adds Andrea Paul, MD, the medical advisor for Illuminate Labs, "At least one medical trial found that crude onion juice applied topically was effective in treating hair loss caused by alopecia areata." Dr. Paul explains that this non-standard pattern of hair loss is often caused by auto-immune conditions. Published in the Journal of Dermatology, the study Dr. Paul mentions found that participants with these health concerns saw some hair regrowth after two weeks of onion juice treatment. Four weeks later, 73.9 percent of patients saw hair regrowth. Six weeks later, 89.6 percent of patients saw hair regrowth.
High sulfur content is what gives onion juice its anti-inflammatory properties to potentially treat alopecia areata, but that's not enough to effectively treat other types of baldness. "Most hair loss is due to androgenetic alopecia, like male or female pattern baldness, and there is no research to suggest that onion juice provides any benefit for this common genetic condition," explains Dr. Alan Bauman, an ABHRS-certified hair restoration surgeon. The reason? Male and female pattern baldness is caused by a genetic sensitivity to a sex hormone, and there is "no evidence that onion juice will help to reduce this sensitivity" when applied topically, Dr. Bauman notes. But if your hair loss is related to those aforementioned causes, Dr. Paul suggests giving onion juice a try, especially since there are no real health risks involved.
What's the Science Behind This Ingredient?
We've established that sulfur is the chemical that helps onion juice decrease hair loss, but how does the ingredient make our hair grow? It all comes down to giving your cells and hair follicles a boost. "Hair is made from a protein called keratin," Young explains, "and the main building blocks of protein are amino acids." Because onions have high levels of amino acids due to all that sulfur, topically applying onion juice to the scalp provides the necessary amino acids and B vitamins that aid in cell regeneration (which, in turn, results in the restoration of hair follicles).
Beyond cell regeneration, onion juice contributes to overall scalp health, as well. Specifically, those high sulfur levels help cleanse the scalp, which can unclog follicles and jumpstart their growth, says Dr. Cheryl Rosen, the director of dermatology at BowTied Life. Onions also boast high levels of antioxidants, as well as anti-fungal and antibacterial properties, Dr. Bauman adds. That means onion juice can both help protect hair from environmental damage and prevent scalp infections. While this agent is safe to use and has notable benefits, Dr. Rosen emphasizes that it's not a medically approved treatment, so it should not be used as a replacement for any prescribed treatments.
How Can You Incorporate Onion Juice Into Your Hair Care Routine?
"There are a few hair products that include onion juice as an ingredient for hair loss," Dr. Rosen says. She particularly recommends Rogaine Hair Regrowth Treatment for Men ($51.99, rogaine.com), which includes onion extract, and Wild Growth Hair Oil ($8.99, amazon.com), which also includes onion extract. However, since the previously referenced study from the Journal of Dermatology based its findings on crude onion juice, our experts suggest following DIY methods for optimal results. "The sulfur compounds work best when they are fresh," Young explains. "Store products tend to include preservatives which would minimize the onion juice's potency." To follow the exact methods employed in the medical study, you'll need Australian brown onions and a blender, Dr. Paul says. "The onions were chopped into small pieces and juiced using a blender. No additives were used in the study, so it seems logical to avoid additives when creating the solution," she explains. The study specifies applying the crude onion juice to the scalp twice daily, though it doesn't specify any timing beyond that. "For convenience, it probably makes sense to apply the treatment prior to showers, as it will be quite pungent," Dr. Paul adds.
Young recommends another DIY method with some additional steps: First, boil two cups of water and add in one chopped medium onion. Then, let the mixture simmer for 10 minutes on medium heat (Young says this enhances the sulfide compounds). Next, strain the onion water and let it stand for five minutes. Add one tablespoon of cayenne pepper, which can stimulate blood flow and help the scalp absorb the juice, notes Young. Then, add one tablespoon of honey for its natural antibacterial properties; it also thickens the solution. Young recommends pouring the mixture into an applicator bottle before using the solution on a dry, unwashed scalp. Once applied, put on a shower cap and leave the onion juice on your scalp for two hours. When time is up, just rinse it off. "Neutralize the odor by using an apple cider vinegar rinse with water," Young adds. Bonus: You can refrigerate any leftovers for up to five days.