From apple cider rinses to beer treatments, hair enthusiasts have tried a variety of unusual remedies in pursuit of stronger, shinier strands. One trend making the rounds is onion water, a DIY solution claimed to enhance hair growth and scalp health. But does this home concoction live up to the hype? Dermatologists weigh in.
What Is Onion Water for Hair?
Onion water is made by soaking sliced raw onions in water, allowing their sulfur-rich juices, flavonoids, and antioxidants to infuse the liquid. This mixture is then applied directly to the scalp and hair.
“Onion water may improve the strength and appearance of hair by supporting healthy scalp skin and protecting hair follicles from oxidative stress,” says Brendan Camp, MD, FAAD, a board-certified dermatologist at MDCS Dermatology in New York City.
Candace Spann, MD, FAAD, a dermatologist in Las Vegas, adds that onion water may also benefit the scalp. “Sulfates in onion water can help soothe scalp dermatitis, reduce itchiness, and potentially encourage hair growth,” she explains.
What the Research Says
Evidence supporting onion water is limited but promising. A 2002 study showed hair regrowth in nearly 87% of participants with alopecia areata who applied onion juice twice daily. The flavonoid quercetin found in onions is thought to improve blood flow to hair follicles, though it does not affect hormones like DHT, which are linked to pattern baldness.
“While onion water is an intriguing natural option, it isn’t a replacement for scientifically proven treatments like minoxidil,” Dr. Camp notes.
Potential Side Effects
DIY hair remedies carry risks. “Homemade preparations are often highly concentrated and can cause irritation, redness, itching, or scalp rash,” warns Nathan Newman, MD, FAAD, a dermatologist and cosmetic surgeon.
Other drawbacks include the strong odor and potential temporary hair discoloration—light-colored hair may develop a yellowish tint with frequent use.
How to Approach Onion Water Safely
For those interested in trying onion water, some commercial hair products contain onion extract or juice combined with other nourishing ingredients, offering a safer, more balanced option.
However, dermatologists emphasize that those experiencing hair loss should consider FDA-approved treatments. “Minoxidil is the only FDA-approved topical treatment for hair loss, and topical finasteride may also help,” Dr. Spann says. Dr. Camp adds that ketoconazole shampoo can promote a healthier scalp, supporting stronger, shinier hair.
If hair loss persists, consulting a dermatologist is recommended. “Hair loss can have many underlying causes, many of which are treatable,” Dr. Newman explains.
