by Nancy Nachman-Hunt

That is the question.

Hair. It’s quite literally our crowning glory. Most of us spend more time on it than we do on any other daily beauty regimen. We wash it, condition it and curl or straighten it. Oh, and one more thing—we color it. Millions of us do. Some 42 percent of women and 25 percent of men in the U.S. dye their hair, according to New Jersey-based industry consultants Kline & Co.

In our rush to beauty, how many of us consider the safety of hair dyes? If the mirror reveals any telltale strands of gray or if fashion dictates, we’re either off to the salon or off to the drugstore to buy something to infuse color into our locks. And if we think at all about whether hair dye is safe, the word “natural” on a package of hair coloring product is bound to pique our interest. The question is, should it?

The answer is complex. For the uninitiated, there are three types of hair dye: permanent, semi-permanent and temporary. Permanent hair dye colors the hair from the inside out. It uses a catalyst, like peroxide or ammonia (or both), to roughen the hair cuticle so the dye can deposit into the hair shaft, where it stays until the hair grows out. If you’re perusing the drugstore shelf for permanent hair dye, manufacturers such as Clairol use the phrase “level 3” to indicate permanent hair dye. Semi-permanent dyes, or “levels 1 and 2” in Clairol’s parlance, use less peroxide and no ammonia, and they color only the outside of the hair shaft. This type of coloring fades after repeated washings. Temporary hair color does not use a catalyst and, as its name suggests, must be reapplied after each washing. Natural or plant-based dyes are most often, but not always, akin to level 1 and 2 hair-coloring products.

Is natural really better?

Are natural or plant-based pigments safer than synthetic? The debate rages on. First, natural personal-care products like hair dye are not regulated by the FDA, although synthetic, or chemically based, personal-care products are. (One exception is henna, which the FDA has approved for hair coloring.)

Next, the vast majority of studies on hair dye safety have concentrated on synthetic dyes. Controlled clinical studies on the toxicity of natural, or plant-based, hair dyes are virtually nonexistent, according to Tim Kropp, senior scientist at the Washington, DC-based Environmental Working Group (EWG), which has published an in-depth report on personal-care product safety. Because of this lack of scientific scrutiny, “Overall, you can’t make a distinction broadly about synthetic versus natural hair dye. You can’t just say that [natural] is going to be better,” he says. The best Kropp can currently say about natural hair dye is that judging solely by their characteristics, natural hair dyes are “probably safer than synthetic.”

Research has concentrated almost exclusively on synthetic hair dye safety largely because synthetics are so prevalent in the marketplace and because no distinction has been made in any widely published study between natural and synthetic dye. Synthetics are the dyes of choice because they can produce the kind of hair color that consumers demand, according to professional hair colorists. Plant-based dyes tend to create more subtle hair color. They don’t provide what Julie Hinshaw, owner of Wildflowers Salon and Spa