With all the focus and transition to natural hairstyles, more people are embracing their natural hair textures. The CROWN ACT has made it illegal to discriminate against natural hairstyles in many states. California’s Proposition 65 requires businesses to provide warnings to Californians about significant exposures to chemicals that cause cancer, birth defects or other reproductive harm. Some chemicals are even banned from use in the state of California, exercising prescience in protecting its citizens against harmful pesticides, preservatives, food, and personal and hair care ingredients by banning them from use—period. For those of us who do not reside in the California, we must take personal responsibility and accountability for our personal care. This means reading labels, following the Environmental Working Group’s (EWG’s) recommendations. Natural hair care lines promote “paraben-free,” “phthalate-free,” “no silicones”… 

But what about hair color? Prior findings on the association between hair dye use and breast cancer have been inconsistent; while a few studies have reported a positive association, many concluded that there was no elevated risk.¹ As it relates to bladder cancer, although there was no relation between hair dye use and bladder cancer risk in women overall, they did detect evidence of associations and gene-environment interaction with permanent hair dye use. In this same study, they did remark that the carcinogenic potential of dark colored permanent hair dyes are of greatest concern. Permanent hair dyes consist of dye intermediates (aromatic amines) and couplers, which can react with each other to form pigment molecules. The shades of color are approximately proportional to the concentration of ingredients (a clear estimate cannot be made because of the complexity of ingredients)—darker hair dyes tend to contain higher concentrations of ingredients, whereas lighter shades contain lower concentrations. Additionally, lead acetate based dark colored products can still be found on the international market.²

In July 2021 the International Journal of Cancer published a study revealing that hair dye use is very common and it has been estimated that more than one-third of women above the age of 18 in the United States use hair dye. Hair products contain more than 5,000 chemicals, including those with mutagenic and endocrine disrupting properties such as aromatic amines. Dye constituents, such as 2,4-diaminoanisole sulfate and para-Phenylenediamine, have been found to induce tumors in the mammary gland of rats. Other aromatic amines including 4-aminobiphenyl-(ABP) can reach breast tissue; women who used hair dye in the past year were 8 times more likely to have ABP-DNA adducts in breast ductal epithelial cells.³ Despite these observations, epidemiologic data to date on the potential association between hair dye use and bladder cancer risk are equivocal. When my patients inquire about the risk of breast cancer with hair dye use, I recommend semi-permanent or demi-permanent, or natural hair colors. If permanent hair color is used, it should not be used more than twice per year. Keep in mind that there is no clear guidance on this, but I do believe in this case, that less is more.

As a personal user of permanent hair dyes and hair bleaching agents, my hair colors have ranged from light brow to blonde highlights, raspberry, purple, mermaid blue, leprechaun green, and this month, it’s an auburn/blond-ish color—and that’s just in the past two years. I must say that the research conducted to compose this column ranges from concerning and disturbing to “is that the final answer?” I am so glad that we have so many options for natural hair color agents today. If you look on the internet, you will find a plethora of information and ingredients for DIY hair coloring using anything from carrot juice to beets. Kudos to you if you have the creativity, patience, time, they type of hair, and all else required to do this. For the rest of us, there is are Henna options and many ammonia-free and para-Phenalynediamine (PPD)-free options on the market. Let’s talk about henna. Henna is a 100% natural alternative to traditional hair dyes full of chemicals, which contain besides the well-known ammonia, many other harmful ingredients (PPD, hydrogen peroxide, resorcinol, lead acetate). Why is the PPD found in hair dyes “harmful?” As a board-certified dermatologist, I have seen allergic contact dermatitis (ACD) from PPD. The thing is, one does not know that they are allergic until they actually get their hair dyes black or get a black henna tattoo. Symptoms of a PPD allergy include swollen eye and face (like you went a round or two with Mike Tyson), itchy, red scalp. The tell-tale sign is seeing this in a patient who walks in with jet-black hair. Just make sure that your colorist is informed of this allergy as some may mix dyes with black to achieve your desired hair color. So, if you have no PPD allergy, you should be okay.

Natural henna and henna-based hair dyes (those containing only plants) do not damage the hair, on the contrary, they are a natural treatment that strengthens the hair and gives it shine. Unlike chemical hair dyes that penetrate and destroy the hair, henna coats the hair.


Types of Henna-Based dyes

Henna hair dye is made from the leaves of the lawsonia inermis tree, a spiny tropical plant, harvested and ground into a fine, richly pigmented powder. This powder is then mixed with liquid to create a slime-like mixture that is spread on the hair in the process of hair coloring. The main producers of henna are the countries of the Arab world and the Middle East, where the plant is found. The leaves of this plant contain natural pigment. Each producer has its own colored henna for hair. Pure henna colors hair in shades ranging from peach to red depending on the color it is applied to.

• Iranian Henna. When used alone, Iranian henna gives a bright red color. Mixed with various additives, it offers hair a warm caramel to a rich chocolate glow.
• Sudanese Henna. Made in Saudi Arabia and supplied as a green powder. Provides a long-lasting copper tint. Brown and reddish colors are obtained if mixed with other herbal additives.
• Indian Henna. Indian henna is often used as a remedy to prevent hair loss and dandruff. It usually comes in five shades: gold, burgundy, brown, black and mahogany. To vary the shades, it is mixed with herbal additives in the form of wine, coffee, beetroot juice and tea.
• Colorless Henna. Colorless henna is produced from the stems of the plant, in which there is no dye. The main purpose is to treat hair, remove dandruff, restore shine, reduces the appearance of greasy hair.
• White Henna. White henna cannot be classified as a completely natural product. In its creation, chemical ingredients of an aggressive nature are used that act on the hair as artificial shiners.

The Benefits of Henna

Hair dyes containing henna are 100% natural, unless henna is mixed with other plants. Some of its numerous benefits for hair:

• No “toxic” chemicals. This is clearly the biggest advantage of henna hair coloring. On the opposite, conventional dyes can cause scalp burns, irritation, and allergic reactions.
• Stronger hair. Henna pigment molecules penetrate the hair cuticle and fuse with keratin. This process makes the hair stronger, but also makes removal harder.
• Smoother, shinier hair. Henna coats the hair, making it shinier. Because it adheres to the damaged areas, it repairs the hair making it easier for everyday styling.
• A color that doesn’t fade easily. Conventional hair coloring shades fade after repeated washing. The henna shade stays on your hair for a long time.
• Great for white hair coverage. Successfully covers white threads. Henna dyes have a very high covering power, so white hair can be dyed successfully.
• Low cost. Henna is much less expensive than even the cheapest chemical dyes on the market. One box of henna will get you from 2 to 10 hair treatments, depending on the length of your hair.

Just like traditional hair dyes, henna will keep its shiny hue only for a while, usually from 4 to 6 weeks. Repeated applications of henna and other herbal dyes have the effect of intensifying the shade. Natural henna is a permanent hair dye, but it is subject to external factors (sun, chlorine, hair dryer, frequent washing, care and styling products full of aggressive chemical ingredients, etc.). Natural hair coloring based on henna offers many benefits to the hair. Unlike ordinary hair dyes, henna-based dyes are 100% natural, contain no ammonia, and no chemical dyes or preservatives. At the top of the year, Cosmopolitan magazine composed a list of the best natural hair care kits or agents available.
I must say that this list was encouraging. Whatever you choose, I do recommend selecting a hair coloring kit with natural oils and plant extracts. The hair dyeing process is so drying, we should do our best to ass moisture to protect the hair shaft. Otherwise, hair breakage will become another concern, and let’s face it—we have enough to deal with already. 

References

1. Personal use of permanent hair dyes and cancer risk and mortality in US women: prospective cohort study. Zhang Y, Birmann BM, Han J, Giovannucci EL, Speizer FE, Stampfer MJ, Rosner BA, Schernhammer ES.BMJ. 2020 Sep 2;370:m2942
2. Hair dye use and risk of bladder cancer in the New England bladder cancer study. Stella Koutros 1, Debra T Silverman, Dalsu Baris, Shelia Hoar 2. Zahm, Lindsay M Morton, Joanne S Colt, David W Hein, Lee E Moore, Alison Johnson, Molly Schwenn, Sai Cherala, Alan Schned, Mark A Doll, Nathaniel Rothman, Margaret R Karagas Int J Cancer. 2021 May 1;148(9):2255-2263.
3. Int J Cancer. 2020 Jul 15; 147(2): 383–391. Hair dye and chemical straightener use and breast cancer risk in a large US population of black and white women. Carolyn E. Eberle,1 Dale P. Sandler, 2 Kyla W. Taylor, 3 and Alexandra J. White2

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Sharleen St. Surin-Lord
Dermatologist
derm@visagederm
www.visagederm.com

Dr. Sharleen St. Surin-Lord is a board-certified dermatologist who has been practicing for more than 13 years. She is in private practice at Visage Dermatology, Largo MD. She also practices at the University of Maryland Capital Regional Health System in Maryland and she is an assistant professor of dermatology at Howard University College of Medicine. Dr. Sharleen is a member of the American Hair Research Society and you can follow her on Twitter, Instagram, and Facebook as DermHairDoc.