The Truth About Shampoo & Conditioner

This week, we’re bringing you the facts on your beloved hair care products. We use shampoo and conditioner on a regular basis. You’d think that such essential products would be simple to make and wouldn’t contain harmful chemicals, right?

Shampoos and conditioners are made with ingredients that are very common, but that doesn’t mean they’re necessarily safe to use. Hair care products are highly engineered, and they’re trickier to make than you might think. Shampoos have been designed to lather abundantly and leave your hair feeling “squeaky” clean. Conditioners are then added to moisturize and coat the hair without leaving an oily residue.

But that shampoo may be stripping your hair of the natural oils that it needs to remain healthy. Your scalp actually has a biome just like the rest of your body, and natural oils are a part of that. In addition, conventional shampoo can leave buildup and residues. So that squeaky clean feeling that we’re used to doesn’t necessarily mean “clean” or “healthy” at all.

What exactly makes these products so difficult to formulate if brands want to check the boxes of “clean,” “healthy,” and shelf-stable? In the world of beauty products, some of the greatest problems known to green beauty insiders include surfactants, emulsifiers and preservatives—all common ingredients in shampoos and conditioners.

Here’s more on the specifics.


Surfactants, for example:

  • Sodium Laureth Sulfate
  • Sodium Lauryl Sulfate

Surfactants make a product suds or lather. Because sudsing doesn’t actually occur much in nature, lather is often created because of a chemical reaction or agent. Sometimes dispensers can make things foam because of how they function, but often there’s a problematic ingredient (or several) in there too. While most sudsing ingredients aren’t toxic to humans (although they can be powerful irritants to many), they’re often harmful to aquatic life. Given that our shampoos go down the drain in large quantities, it makes sense to use ingredients that are safe for the whole ecosystem.

Preservatives, for example:

  • Parabens
  • quaternium-15
  • DMDM hydantoin
  • imidazolidinyl urea
  • diazolidinyl urea
  • polyoxymethylene urea
  • sodium hydroxymethylglycinate
  • 2-bromo-2-nitropropane-1,3-diol (bromopol)
  • glyoxal

Preservatives make products shelf-stable and allow them to last for long periods of time without expiring or separating, and prevent the growth of yeast, mold, bacteria, fungi and other microorganisms. Preservatives are tricky though, because many have a range of toxicity issues for humans and the environment – due to the very fact that they’re designed to kill things. For example, parabens are linked to breast cancer, and others listed above release formaldehyde, a known carcinogen.

Fragrance: This is often used as an umbrella term for up to a hundred different ingredients that make up a single “fragrance.” Unfortunately, many common fragrance ingredients can be toxic to human health, including phthalates (linked to reproductive and developmental harm) and synthetic musks (linked to hormone disruption and build-up in our bodies).


Conditioner suffers from the same pitfalls as shampoo with surfactants, preservatives, and fragrance, plus one more.

Emulsifiers, for example:

  • Ethanolamines: DEA, TEA and MEA
  • Chemicals ending in “siloxane”

These chemicals help combine oil and water, so the conditioner won’t separate. They’re also the softening agents which can leave hair feeling silky soft. Siloxanes are a good example of effective emulsifiers, but they’re also shown to persist (not break down) in the environment.

Discover MADE SAFE Certified Hair Care

    MADE SAFE certified products have been screened by scientists for known carcinogens, endocrine disruptors, reproductive toxins, neurotoxins, behavioral toxins, flame retardants, heavy metals, high-risk pesticides, insecticides, toxic solvents, and harmful VOCs. Ingredients have been further examined by a chemist for bioaccumulation (builds up in human bodies), persistence (builds up in the environment), ecosystem harm, as well as for general and aquatic toxicity.

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