Americans spend almost one hundred billion dollars per year on cosmetics and personal care products.1 This accounts for over one fourth of all cosmetic spending in the world!2 Over her lifetime, the average woman in developed countries will invest as much as twelve thousand dollars on hair dye alone.3 But this one isn’t just for the ladies—many men also dye their hair, and not just older men. Over the past twenty years, the proportion of men who dye their hair has been steadily increasing to its current level of about one in ten men.4
Yet chasing beauty (or vanity) comes with a cost, and not just to the bank account. Personal care products and cosmetics—including hair dyes—contain a wide array of harmful ingredients, including some with well-documented risks and others with potential risks that haven’t even been tested.
THE LARGEST ORGAN
Before discussing hair dyes, it is important to recall that our skin is our largest organ. It should come as no surprise, therefore, that what we put on it quickly ends up in our bloodstream, lymph nodes and other parts of the body. Recent studies confirm that this is the case for pretty much any chemical applied to the skin—including those in sunscreens, deodorants and tattoo inks.
For example, a study published in JAMA in May 2019 reported that it takes just one day of use for sunscreen ingredients “to enter the bloodstream at levels high enough to trigger a government safety investigation.”5 According to a professor of biology at North Carolina State University, substances applied topically can pose even greater dangers to our health than substances that we ingest: “When you eat something, it’s broken down by your liver and digestive system. But when you put something on your skin, there are times when it can enter your bloodstream without being metabolized.”6
A recent study by public health researchers at the University of California-Berkeley suggests that constant chemical exposure from personal care products may be contributing to the rise of early puberty in U.S. girls, particularly following maternal exposure during pregnancy.7 The researchers found that when pregnant women had higher body burdens of phthalates (a group of chemicals often found in fragrances and scented personal care products) and triclosan (a phenol used as an antibacterial), their daughters—but not their sons—experienced puberty at younger ages. A press release about the study described researchers’ suspicion “that many chemicals in personal care products can interfere with natural hormones in our bodies” and pointed to rat studies showing that exposure to these chemicals can alter reproductive development. Unfortunately, girls are facing an onslaught of pressure to use cosmetics and other such products at earlier and earlier ages.
On the male side of the equation, there has been a precipitous drop in sperm counts in developed countries over the past four decades or so—a decline of as much as 50 to 60 percent.8 Researchers believe that this trend, too, may be linked to widespread and constant unnatural exposure to chemicals in everyday products.9
A HOST OF HAIRY CHEMICALS
What about hair dyes and their potential risks? Although consumers may not realize it, hair dyes are a veritable stew of chemical factory sludge. The National Cancer Institute (NCI) estimates that companies use over five thousand different chemicals in the manufacture of modern hair dye products.10 Many of these chemicals are known endocrine and hormone disruptors, classified as probable carcinogens by the International Agency for Research on Cancer (IARC),11 while many more have received little to no study at all for safety.
While it may be difficult to prove definitively that the chemicals in hair dyes lead to increased health problems such as cancer, the available evidence is troubling. Describing non-Hodgkin lymphoma (which typically arises in the lymph nodes), the NCI points to research showing that hair dye users had increased risks for several different subtypes, particularly in women who started dyeing their hair before 1980.10 The NCI adds, “Although these results are consistent with the idea that earlier hair dyes were more carcinogenic, it is also possible that the absence of increased risks for hair dye users who began using dyes after 1980 reflects lower cumulative exposure levels or insufficient time since first exposure for any increase in risk to become apparent.”10
Numerous other studies have found associations between hair dyes and increased rates of various types of cancer12 and other diseases.13 (A comprehensive list of studies on hair dyes and their links to cancer published in 2013 is worth perusing.14) Given the types of chemicals used in hair dyes, this isn’t surprising.
TWO COMMON HAIR DYE CHEMICALS
Let’s look at two of the most common chemicals found in hair dyes: PPD (paraphenylenediamine) and PTD (paratoluenediamine or toluene-2,5-diamine). These two chemicals play a key role in the formulations where they are found, forcing open the hair’s cuticle so that it will accept a new color.
Madison Reed, a home hair color company that brags about its avoidance of “harsh” ingredients, describes why PPD has a “reputation for negative side effects”:
Most commonly, PPD can cause reactions ranging from mild skin irritation to more severe allergic contact dermatitis. Sensitive individuals may experience dermatitis—skin inflammation and irritation commonly referred to as eczema. Eczema may first be noticed on the upper eyelids or rims of the ears after application of the hair color. . . . In more serious cases, there may be marked reddening and swelling on the scalp and the face. An allergy to PPD can result in widespread contact dermatitis, as well as hives and, in rare severe cases, anaphylaxis. . . [P]eople who frequently work with PPD—such as hair colorists—often develop dermatitis on their hands. This can occasionally spread to the arms and even the chest.15
However, the alternative to PPD used by Madison Reed—PTD—also has some significant safety concerns. In 2007, the European Commission’s Scientific Committee on Consumer Products issued its opinion that use of PTD “cannot be considered safe based on the available data” and described the chemical as “an extremely potent skin sensitiser.”16 The committee recommended that studies on genotoxicity and mutagenicity in “finished hair dye formulations” be conducted in accordance with relevant scientific guidelines.
FOUR THOUSAND NINE HUNDRED AND NINETY-EIGHT TO GO
Note that PPD and PTD are just two possible chemicals in hair dyes, out of five thousand! What problems and risks might be associated with other ingredients?
Take a look at a single hair dye product and ponder the ingredients, which are just for one part of the kit:
Isoascorbic acid, polyglyceryl-4 oleyl ether, oleic acid, oleyl alcohol, phenyl methyl pyrazolone, sodium metabisulfite, fragrance/perfume, monoethanolamine (MEA), polyglyceryl-2 oleyl ether, resorcinol, water, trideceth-2 carboxamide MEA, pentasodium pentetate, 2-Amino-3-hydroxypyridine, ethanol/SD Alcohol 40, ammonium hydroxide, hexylene glycol, PEG-2 oleamine, ammonium acetate, sodium diethylaminopropyl cocoaspartamide, p-aminophenol and 2-methylresorcinol.17
Compare the above list with Silk and Stone’s three hair dye ingredients: “indigofera tinctoria (indigo), lawsonia inermis (henna) and neem.” It reminds me of when we first started reading food labels!
The mix of dyes, bleaching agents, artificial fragrances and other chemicals present in hair dyes is not something most people would ever tolerate in food, so why do people think it is any better repeatedly applied to the head? European versions of many American foods contain completely different ingredients from those found in the same U.S.-based products; in similar fashion, hair dyes available in the EU may not contain over two hundred banned chemicals—but few if any of those same chemicals are off-limits in the U.S. The bottom line is that U.S. consumers face products with far more risk.
Another consideration with modern cosmetics, including hair dyes, is the lack of studies on complete formulations. Like vaccines and pesticides, individual ingredients are often married to other chemicals to make them more potent, but safety studies generally look at each chemical on its own—and often only study a few of the chemicals at all. There is some irony in conducting isolated research on single chemicals when manufacturers purposefully create their formulas to have greater activity and impact when combined. Research on combined and synergistic effects is much needed but almost completely lacking.
ARE NATURAL ALTERNATIVES ANY BETTER, AND DO THEY WORK?
Since it appears best to avoid standard hair dyeing approaches, what about the natural alternatives? There are many ways to color your hair naturally, in fact, from my daughter’s favorite summertime highlights (acquired by spending as much time outdoors in the sun as she possibly can) to all sorts of recipes and approaches that use common foods and plants.
Natural hair dyes have two main drawbacks. The first is the issue of durability. Because natural approaches generally do not use dangerous and harsh chemicals to force open the cuticles, they don’t penetrate as deeply into the hair, and thus don’t last nearly as long. The second issue is that of the color palette. Natural approaches simply will not offer the range of colors one can get with modern hair dyes. You aren’t going to get a bubble gum pink or sonic the hedgehog blue and—depending on your natural hair color—you may have trouble getting too far from your original shade.
Nonetheless, there are a fair number of organic and natural brands of hair dyes on the market these days, many with far safer formulations and good customer reviews. Unfortunately, I have reached the point where I have too little hair left to try them out! However, just because a hair product is natural or organic does not guarantee that a consumer will not have a reaction or issue with a particular product or ingredient. Moreover, claims of “natural” or “organic” ingredients should not be taken at face value—check the ingredients just as you would do for food or any other product. Many so-called natural formulations still use a number of problematic ingredients, like those already mentioned, to get the naturally derived colors to penetrate and stay.
PLANT-BASED HAIR DYES
The level and intensity of modern cosmetic use, especially in the U.S., may be somewhat of an anomaly, but “painting the barn,” as the saying goes, is many thousands of years old. While doing research for The Elderberry Book,18 I came across a number of studies on Greco-Roman body care and cosmetics, and found that the elder (usually called elderberry in the U.S.) was used in many different cosmetic preparations, including all-natural hair dyes. Other cultures have used coffee grounds, herbs and other plants to make cosmetics, including ones for the hair.
A number of natural storebought formulations use plant-based ingredients: beet, turmeric, alum, neem and more. Henna is one of the most popular natural hair coloring options, and many major brands now offer henna-based lines in response to consumer demand. Usually, these products use henna or other natural ingredients in combination with one another to produce varied and desired shades and tones.
DIET AND LIFESTYLE
Why does our hair lose its color to begin with? Well, no one is quite sure! A number of factors appear to play a part, with genetics and the immune system ranking near the top.19 Also, dietary deficiencies, including nutrients such as folate and vitamin B12, can lead to an early gray (and grave)!20 Eating well and living well may not prevent your hair from losing its natural color, but for some people, a healthy diet and lifestyle may delay and minimize the progression. At the end of the day, we should all realize that a gray head is a “crown of glory”—something to embrace as we age instead of risk our health trying to prevent.
HOW HAIR DYES WORK
If you have ever painted your house, you have a bit of an idea how hair dyes work. Generally, you start by using a primer to create a flat color on which to put the new color. In hair dyes, this is often done by using bleaching and similar agents.
Then, you apply the paint, which often contains numerous additional chemicals—usually volatile organic compounds (VOCs)—added to get the paint to spread evenly and stick to the surface. With hair dyes, various chemicals help the pigments “stick” by altering the pH of your hair and forcing open the cuticles, where hair color is found.
THREE NATURAL HAIR-DYEING TIPS AND TRICKS
1. If you want to try natural dyes but do not want to risk a fiasco around your face, save some of the locks next time you get your hair cut—this will give you some hair with which to experiment without risking your whole head!
2. Your shampoo, conditioner and other hair care products can make a big difference to the effectiveness of natural hair dyes. Some ingredients—like silicone or glycerin—can create a barrier on your hair that prevents pigments from working properly. Make sure your shampoo or other hair care products won’t cause problems.
3. Know that natural approaches take about two days to set fully, so it is best to go easy on your hair until the third day to get the maximum benefit and duration from the new shade.
1. Retail sales of beauty and personal care products in the United States from 2016 to 2018 (in billion U.S. dollars. https://www.statista.com/statistics/997359/us-sales-of-beauty-personal-care-products/.
2. Kratofil C. Can you guess how much a woman spends on makeup in her lifetime? (We were way off!) People, March 30, 2017.
3. March B. Women spend nearly £10k on hair colouring over a lifetime. Cosmopolitan, Sep. 2, 2013. https://www.cosmopolitan.com/uk/beauty-hair/news/a22346/average-cost-of-colouring-hair/.
4. McKenna A. To dye or not to dye. Emerita, March 2012.
5. LaMotte S. Sunscreen enters bloodstream after just one day of use, study says. CNN, May 6, 2019.
6. Heid M. 5 things wrong with your deodorant. TIME, July 5, 2016.
7. Manke K. Prenatal exposure to chemicals in personal care products may speed puberty in girls. Berkeley News, Dec. 3, 2018.
8. Levine H, Jørgensen N, Martino-Andrade A et al. Temporal trends in sperm count: a systematic review and meta-regression analysis. Hum Reprod Update 2017;23(6):646-59.
9. Carr T. Sperm counts are on the decline—could plastics be to blame? The Guardian, May 24, 2019.
10. Hair dyes and cancer risk. https://www.cancer.gov/about-cancer/causesprevention/risk/myths/hair-dyes-fact-sheet.
11. World Health Organization. Some Aromatic Amines, Organic Dyes, and Related Exposures. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Vol. 99. Lyon, France: 2010.
12. Gera R, Mokbel R, Igor I, Mokbel K. Does the use of hair dyes increase the risk of developing breast cancer? A meta-analysis and review of the literature. Anticancer Res 2018;38(2):707-716.
13. Liu B, Jin SF, Li HC et al. The bio-safety concerns of three domestic temporary hair dye molecules: fuchsin basic, Victoria blue b and basic red 2. Molecules 2019;24(9).
14. Saitta P, Cook CE, Messina JL et al. Is there a true concern regarding the use of hair dye and malignancy development? A review of the epidemiological evidence relating personal hair dye use to the risk of malignancy. J Clin Aesthet Dermatol 2013;6(1):39-46.
15. All about PPD (and why we don’t use it). https://www.madison-reed.com/blog/ppd-and-why-we-don-t-use-it.
16. European Commission. Opinion on Toluene-2,5-diamine. Scientific Committee on Consumer Products. Brussels; 2007. https://ec.europa.eu/health/ph_risk/committees/04_sccp/docs/sccp_o_108.pdf.
17. Velez C. Loreal hair dye ingredients. https://www.leaf.tv/articles/loreal-hair-dye-ingredients/.
18. Moody J. The Elderberry Book: Forage, Cultivate, Prepare, Preserve. New Society Publishers; 2019.
19. Gander K. Why does hair turn gray? Scientists may have found a new answer. Newsweek, May 4, 2018.
20. Renee J. Does poor nutrition make your hair grey? SFGate, Nov. 28, 2018.