How Hair Care Ingredients May Be Affecting Your Health

Edited by Olivia Spahn-Vieira  

I love hair care - some might even call me an addict. But for the longest time, I didn’t stop to think about what I was putting on my head. It’s common knowledge that sulfates are bad for your hair, but what about all those other ingredients listed on the back of the bottle? It wasn’t until a TikTok popped up on my For You Page that I even stopped to consider what harmful chemicals were in my everyday products. I started to do some research and was shocked to find that many of the products I use every day contain chemicals that are awful for my hair and health. I felt that this information could be useful for others out there so I’ve compiled a list of some chemicals to steer clear of, followed by recommended ingredients to incorporate into your routine instead. 

  1. 1. Sulfates and Parabens

    I’ve grouped these two chemicals together, since they are some of the better-known toxins to veer away from. Sulfates such as Ammonium Lauryl Sulfate or Sodium Laureth Sulfate (SLES) are a common hair no-no and are some of the more frequently used chemicals in hair care products. SLES can be irritating for those with sensitive scalps, because it strips hair of its natural oils, causing frizziness. Parabens, another common chemical used in hair products, are used to prevent bacteria growth in shampoos may be toxic. Though unproven, some studies have shown that parabens have been linked to the increased growth of breast cancer cells.

  2. 2. DMDM Hydantoin

    You might have seen or heard about this chemical in the news, or as I did, on TikTok. TRESemmé recently underwent a class-action lawsuit with users claiming that DMDM Hydantoin was responsible for hair loss and scalp irritation. Often used as a preservative in shampoos, DMDM Hydantoin is a carcinogen that releases small amounts of formaldehyde overtime and studies have linked it to cancer. It is often used to increase a product’s shelf life by prevent mold from forming but can be absorbed through the scalp when it comes into contact with water.

  3. 3. Sodium Chloride

    This ingredient took me by surprise. Why would anyone put salt in hair products? It turns out that sodium chloride is frequently used as a thickening agent in products in order to give them a better consistency. It is also used to give them a creamier texture, but at what cost? According to The Hair Routine Journal, an online blog, sodium chloride strips your scalp of its natural oils and breaks down keratin treatments. It also prevents hair from absorbing moisture, which can lead to breakage. 

  4. 4. Polyethylene Glycols (PEG)

    According to David Suzuki's website, PEG's are used as a thickening agent but are linked to hazardous chemicals such as ethylene oxide and 1,4 dioxane, which are linked to nervous system damage and issues with human development. These chemicals also contribute to environmental issues, since they are not easy to break down. If it's bad for the Earth, it has no place in my bathroom, let alone on my head. 

  5. 5. Diethanolamine

    Abbreviated as DEA, this chemical is used as a foaming agent in products as well as a way to adjust a product’s pH level. The FDA published an article detailing that DEA is a carcinogen that has been linked to cancer, although it has not been proven. Nonetheless, I’m not putting it on my head anytime soon.


At this point, you might be wondering what good you can put in your hair? No worries, I’ve got you covered. Some good ingredients to look out for:

Oils - Coconut oil, jojoba oil, and avocado oil are great alternatives to many of the chemicals found in hair products. For one, they are all natural while being moisturizing and full of nutrients your hair needs. 

Butters - Similar to oils, butters are a great alternative for hair care that won't break your wallet. Some common ones are shea butter and mango butter. Muru muru butter is another popular substitute but may be harder to find depending on where you live. 

Coconut-Based Surfactant - Unlike harmful sulfates, coconut-based surfactants, such as sodium lauroyl methyl isethionate, are derived from coconut and are gentle on skin while being much healthier for hair. 

Proteins - Since hair and nails are made from proteins, it is important to incorporate them into your hair care routine to keep hair strong and healthy. Some common proteins to look for are keratin, wheat protein, and panthenol.



Center for Food Safety and Applied Nutrition. “Diethanolamine.” U.S. Food and Drug Administration, FDA, Dec. 1999, 


Cherney, Kristeen. “Sulfate in Shampoo: What It Is, Fine Hair, Natural Hair, and More.” Healthline, Healthline Media, 3 July 2019, 


“The Dirty Dozen: Formaldehyde-Releasing Preservatives.” David Suzuki Foundation, 12 Feb. 2020, 


“The Dirty Dozen: PEG Compounds and Their Contaminants.” David Suzuki Foundation, 12 Feb. 2020, 


“Exposure to Chemicals in Cosmetics.”, 11 Sept. 2020, 


Schaefer, Katie. “Coconut-Derived Surfactant for Natural Formulations.” Cosmetics & Toiletries, 3 June 2010,


“Sodium Chloride in Hair Care Products.” The Hair Routine, 4 Feb. 2021, 


Stewart, Jaynelle. “9 Oils & Butters Your Hair Will Fall In Love With This Season.” HuffPost, HuffPost, 7 Dec. 2017, 


Wang, Cat. “Can TRESemmé Take You from a Bad Hair Day to a No Hair Day?” Office for Science and Society, 8 Feb. 2021,