11 Common Shampoo Ingredients Linked to Bald Spots & Thinning Hair

A class-action lawsuit filed against popular haircare brand Olaplex in February 2023 alleges that their products caused severe hair loss and scalp injuries.1 This high-profile case has thrust the issue of potentially harmful shampoo ingredients into the spotlight, leaving many consumers wondering: what exactly is in our hair products?

As we share some of shampoo formulations, you’ll be surprised to learn just how many common ingredients experts warn could be damaging your locks. 

Here are 11 super-damaging shampoo ingredients that may be causing bald spots and increasing shedding:

1. Sodium Lauryl Sulfate (SLS)

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This harsh detergent, found in many shampoos, can strip your hair of its natural oils, leading to dryness and breakage. SLS has also been linked to skin irritation and allergic reactions, which can contribute to hair loss.

2. Parabens

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These preservatives, commonly used in shampoos, have been shown to disrupt hormone function, potentially leading to hair loss. Parabens can mimic estrogen in the body, throwing off the delicate balance needed for healthy hair growth.

3. Formaldehyde

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You might be surprised to find this known carcinogen in your shampoo, but it’s often used as a preservative. Formaldehyde can cause scalp irritation and allergic reactions, damaging hair follicles and increasing shedding. (ref)

4. Phthalates

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These chemicals, used to enhance the fragrance and consistency of shampoos, have been linked to hormonal disruptions that can trigger hair loss. Phthalates can also cause scalp inflammation, further weakening hair follicles.

5. Diethanolamine (DEA)

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This foaming agent, found in many shampoos, can react with other ingredients to form nitrosamines, which are known carcinogens. DEA can also cause scalp irritation and allergic reactions, contributing to hair loss.

6. Propylene Glycol

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This moisture-carrying ingredient, often used in shampoos, can cause skin irritation and allergic reactions in some people. When the scalp is constantly irritated, hair follicles can become damaged, leading to increased shedding.

7. Triclosan

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Once a common antibacterial agent in personal care products, triclosan is a known hormone disruptor. (ref) It can accumulate in fat cells, potentially keeping the body in a state of toxicity and affecting hair growth.

8. Polyethylene Glycol (PEG)

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These compounds, used as thickeners and softeners in shampoos, can strip the hair of its natural oils, leading to dryness and breakage. (ref) PEGs can also be contaminated with harmful impurities during manufacturing.

9. Synthetic Fragrances

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Many shampoos contain a cocktail of synthetic fragrances, which can cause scalp irritation and allergic reactions. When the scalp is inflamed, hair follicles can become damaged, increasing hair loss.

10. Mineral Oil

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This cheap, petroleum-derived ingredient, sometimes used in shampoos, can coat the hair and scalp, clogging pores and preventing natural oil production. This can lead to dryness, breakage, and increased shedding.

11. Alcohol

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Certain types of alcohol, like isopropyl alcohol, are used in shampoos to help other ingredients penetrate the hair shaft. However, these drying alcohols can strip the hair of its natural oils, causing brittleness and breakage, which may accelerate hair loss.

Safer Shampoo Alternatives

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With the growing concern over potentially harmful shampoo ingredients, many consumers are seeking safer alternatives to maintain healthy hair and scalp. 

Here are some safer shampoo alternatives to consider:

  • Sulfate-free shampoos: Look for shampoos that use gentle, non-stripping surfactants like cocamidopropyl betaine or decyl glucoside.
  • Natural and organic shampoos: Opt for shampoos that contain plant-derived ingredients and are free from synthetic chemicals.
  • DIY shampoo recipes: Create your own shampoo using simple, natural ingredients like castile soap, aloe vera, and essential oils.

If you’re concerned about hair loss, it’s always best to consult with a dermatologist or trichologist for personalized advice.

Source:
1. NPR

davin
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Davin is a jack-of-all-trades but has professional training and experience in various home and garden subjects. He leans on other experts when needed and edits and fact-checks all articles.