Is Your Shampoo To Blame for Thinning Hair?

Synthetic chemicals used in some shampoos might actually lead to hair loss.

In 1935, DuPont launched a now oft-quoted advertising slogan that extolled the era's enthusiastic optimism about science. “Better things for better living through chemistry” spoke to the promise of progress in the lab leading to products offering more convenience and improved performance. Consumers embraced synthetic compounds over natural products, believing the hype of their heightened efficacy.

Pandora, meet box. Fast forward to now, and the planet is awash in a toxic soup of synthetic compounds, and for what? Often times the synthetic formulations are far less effective than their natural counterparts—and sometimes even detrimental.

Take shampoo. Sure, we get the convenience of shelf-stable products that smell good and create luxuriant lather—but those properties are often achieved through the use of modern chemicals that may not be so great for our hair.

Not to mention what those chemicals can do to the environment once we wash them down the drain.

You may remember when the bad boy of the beauty ingredients world, sodium lauryl sulfate (SLS), started getting so much attention for being an irritant. Well, as it turns out, SLS also may play a role in hair loss. And it's not alone in its ability to turn your head of thick, lustrous locks into something less than thick and lustrous. According to AARP and New York City hair specialist and restoration surgeon Dr. Robert Dorin, there's a whole host of ingredients to avoid.

If your hair seems thinner than before, it could be from a number of causes, and definitely check in with your health care provider. But you might also want to read the ingredient panels on your hair products and look for the following.

These are often included to make a product last longer, but some of them are known for their effect on hormonal balance and may encourage hair loss.

Not that manufacturers are adding things intended to irritate, but nonetheless, there are synthetic ingredients that can cause scalp inflammation and allergic reactions, exacerbating hair loss and making thin hair dry, brittle, and lifeless, says Dorin.

Most hair products have some type of alcohol. Fatty alcohols can actually help condition dry hair—WebMD advises remembering the ones that start with "c" and "s" as those are good for dry hair: Cetearyl alcohol, Cetyl alcohol, and Stearyl alcohol. Avoid other alcohols that are in high concentration (listed in the top four ingredients), as they can dehydrate your hair.

Lanolin, petroleum, and mineral oilDorin says that these ingredients can weigh down thin hair and prevent natural oils from being absorbed. (And that said, I know people who swear by lanolin for their thicker and/or curly hair, so that's a different story.)

Who knew it was all so complicated? Well, actually, we did. This is why we have a million stories on shampoo alternatives, including homemade formulas and no shampoo at all.

Prediction of molecular mechanism of skin irritation after acute exposure to sodium lauryl sulfate. Gunasekar PG; Rogers JV; Kabbur MB; Brinkley WW; Garrett CM; McDougal JN: Toxicologist 2002 Mar; 66(1-S):162

Bondi CA, Marks JL, Wroblewski LB, Raatikainen HS, Lenox SR, Gebhardt KE. Human and Environmental Toxicity of Sodium Lauryl Sulfate (SLS): Evidence for Safe Use in Household Cleaning Products. Environ Health Insights. 2015 Nov 17;9:27-32. doi: 10.4137/EHI.S31765. PMID: 26617461; PMCID: PMC4651417.

"Bleached, But Not by the Sun: Sunscreen Linked to Coral Damage." Environmental Health Perspectives. 2008.

Hon-Wing Leung, Polyethylene Glycol, Editor(s): Philip Wexler, Encyclopedia of Toxicology (Second Edition), Elsevier, 2005, Pages 515-516,