It may surprise you to know that the majority of ingredients in your hair products don't really do much for your hair—they're there to add fragrance and enhance your hair washing experience. Before you choose your next hair care product, here's a checklist of potentially harmful ingredients to look for on their labels:
Formaldehyde & Methylisothiazolinone
Used for: Preserving shelf-life and reducing bacterial growth.
Health Risk: Known carcinogen; Causes headaches.
Phthalates and Fragrance
Used for: Gelling agent; Making fragrance last longer.
Health Risk: Disrupting endocrine balance; Weight gain; Especially harmful to pregnant women.
Diethanolamine (DEA), Momoethanolamine (MEA), and Triethanolamine (TEA)
Used for: Creating Lather.
Health Risk: Links to hormone disruption and kidney and liver cancers.
Propylene Glycol (AKA anti-freeze)
Used for: Preserving shelf-life of products.
Health Risk: Skin irritant and well-known allergen; Linked to liver and kidney problems.
Parabens
Used for: Preserving shelf-life.
Health Risk: Disrupting endocrine balance; Linked to breast cancer tumors.
Polyethelyne Glycol (PEG)
Used for: Thickening products.
Health Risk: Dries out hair; Irritates eyes; Linked to liver and kidney issues.
Sulphates, Sodium Lauryl Sulfate, or Surfucants
Used for: Boosting foam and lather; dissolving dirt.
Health Risk: Harsh on hair, especially processed hair; Can irritate the skin and eyes.
Just remember, the main ingredient in shampoo is water and the key purpose of it is to cleanse. A good lather is only there to make you feel like you're cleaning your hair, but that doesn't reflect how good a shampoo is.
Natural products have also been known to preserve hair dyes and straightening/curling treatments. Since trends go towards natural products, you'll often see "Paraben-free" or "Sulphate-free" highlighted on the label. Keep in mind that if you do opt for a more natural shampoo, you're unlikely to experience the same kind of lather or fragrance that you may be used to. Also, the shelf life of the shampoo may be shortened, since without the chemical preservatives it won't last as long once opened, so choose a smaller bottle.
It's important to note that shampoo manufacturers and even health professionals argue that these potentially dangerous chemicals are used in such small quantities that they do not pose a health risk. However, the FDA does not regulate cosmetic products the same way they do medications, so their standards of risk may be different.
Sources:
Salon.com: "What's Really In Your Shampoo." Salon.com. Web. August 13, 2009.
http://www.salon.com/2009/08/13/shampoo/
thedailybeast.com: "The Science of Shampoo: What the Ingredients Mean." The Daily Beast (Originally from Newsweek) Web. October 8, 2009.
http://www.thedailybeast.com/newsweek/blogs/the-human-condition/2009/10/08/the-science-of-shampoo-what-the-ingredients-mean.html
thedailymail.co.uk: "Are Paint-Stripper Chemicals in Shampoo Destroying Your Hair." The Daily Mail. Web. April 18, 2012.
http://www.dailymail.co.uk/femail/article-2131761/Are-paint-stripper-chemicals-shampoo-destroying-hair.html
