Which gray hair reversal products are worth your money, if any? Dermatologists share

Getting gray hair is an unavoidable part of life. While many embrace their silver or white locks, many people try to turn back time by using gray hair reversal serums and supplements.

Many of these trendy products promise to delay or even reverse gray hair. In the past year alone, online search interest in anti-gray hair serums has climbed 280% in the United States, according to an analysis by NBC News.

So, are there any anti-gray products that can actually prevent or reverse gray hair? TODAY.com spoke to dermatologists about the science behind gray hair to learn more.

What causes hair to go gray?

Unless you dye your hair, it will eventually start to lose color over time, usually beginning when people are in their 30s or 40s, per the Cleveland Clinic. Graying is a completely normal part of life, according to experts. Here's how it works:

"We're all born with a certain number of hair follicles and a predetermined number of hair follicle cycles, and there are little pigment-producing factories in our hair follicles (where hair grows out of the scalp) called melanocytes that give us our hair color," Dr. Mona Gohara, a board-certified dermatologist based in Connecticut, told TODAY in a segment aired August 2.

Hair graying is predominantly due to these melanocytes not renewing, Dr. Jonathan Zippin, dermatologist at Weill Cornell Medicine, tells TODAY.com. Melanocytes live at the midpoint of the hair, says Zippin, and when they need to replicate, they migrate to the base of the hair follicle and produce pigment, or melanin.

There are actually two different types of melanin which dictate hair color — the amount and mixture of these is what makes hair black, brown, red, or blonde.

Graying occurs when "those melanocytes are no longer moving and populating the bottom of the hair,” says Zippin. A lack of these melanin-producing cells at the base causes the hair to appear gray — when there's none at all, the hair is white.

The age at which people start to go gray and the extent to which the hair goes gray or white varies depending on the person.

Why exactly graying happens is not fully understood. “Sometimes the melanocytes get tired. They just don’t want to work anymore,” says Gohara, adding that genetics likely also play a role.

Is gray hair caused by stress?

Apart from aging and genetics, factors like stress or medications may also contribute to the graying process, the experts note. There have been studies in mice that suggest that stress can lead to melanocyte damage, says Zippin, causing the hair to turn gray.

A 2021 study found that stress can lead to gray hair in humans, and taking away that stress appears to reverse the process, allowing white strands to return to the natural color at the root — however, the effects were temporary and limited to a certain age group and only a few hair follicles, TODAY.com previously reported.

“We also know that there are some medicines that can affect the melanocytes or stress them, and in that instance, that could lead to gray hair,” says Zippin.

How can I reverse my gray hair naturally?

In recent years, an increasing number of anti-gray hair products have entered the market, amplified by social media. But, based on the available science, there are no products that "definitively" reverse gray hair, says Zippin.

Some popular anti-gray serums containing ingredients like caffeine, peptides and vitamins promise to reduce the appearance of grays, renew color to the hair and deliver visible results in just a few months when applied daily. Some even claim to have research supporting these assertions.

But can anti-gray serums or any of the active ingredients in them actually stimulate melanin production when applied to the scalp? “Whether the melanocytes are actually nudged is questionable. ... I don’t know that we have any definitive science to say that that’s happening,” says Gohara.

What about gray or white strands caused by stress? “Theoretically, if gray hair is caused by stress and those stressors are removed, that could reverse gray hair, but has that been done pharmacologically? No,” Zippin adds.

Does vitamin B12 reverse gray hair?

In addition to anti-gray serums, some companies also sell supplements that contain blends of vitamins. B12 is an especially popular one, as vitamin B (as well as vitamin A and biotin) have been show to play a role in hair growth and follicle health, according to the Cleveland Clinic.

But can specific vitamins definitively delay or halt the graying process? According to experts, no. There are no scientific studies showing that certain supplements — including vitamin B12 — will prevent or reverse gray hair in humans.

“I think it’s fair to say that we don’t truly understand what causes gray hair. Therefore, it’s hard to know whether any particular product will be successful because we don’t know what mechanism we’re really trying to reverse,” says Zippin.

Are there risks to trying anti-gray serums and supplements?

The U.S. Food and Drug Administration does not review anti-gray hair products for safety before they hit the market, but Gohara said she considers them to be low risk and "pretty safe to try."

Potential side effects may include scalp irritation from serums or gastrointestinal issues from supplements, Gohara added.

“In general, I don’t think any of these are going to hurt anybody,” says Zippin. However, allergic or adverse skin reactions are possible when trying any new serum or topical product.

If you do develop a new irritation or a new rash associated with a product, you should stop using it immediately, Zippin adds.

Gohara suggested trying serums on a small area first and checking with your doctor before trying a new product if you have any questions.

While popular anti-gray products may not harm your health, they can harm your wallet, the experts note. At the end of the day, there's always hair dye — or embracing your natural hair, grays and all.

This article was originally published on TODAY.com