Sulfates are chemicals used as cleansing agents. They’re found in household cleaners, detergents, and even shampoo.

Two main types of sulfates are used in shampoo: sodium lauryl sulfate and sodium laureth sulfate. The purpose of these sulfates is to create a lathering effect to remove oil and dirt from your hair. If your shampoo easily makes a lather in the shower, there’s a good chance it contains sulfates. Sulfate-free shampoos make little to no later.

Compared to other cleansing ingredients in shampoo, sulfates are said to have the deepest cleansing effects. They belong to a class of cleansers called anionic surfactants, which clean away substances.

Sulfates are considered shampooing staples. Still, the use of sulfates in shampoo has been controversial in recent decades. Some people believe that sulfates can directly damage your health. Since shampoo is used daily in many cases, the thought is that this much exposure to sulfates can lead to serious risks. Sulfates were once perceived to be cancer-causing agents, but further scientific evidence debunked these claims.

However, this doesn’t mean that sulfate-containing shampoo is safe or appropriate for everyone. It can be damaging to certain types of hair, and it may even cause skin irritation in some people. Learn more about these possible risks and what you can do about them.

While sulfates are effective at removing dirt and oil from your hair, the problem is that these ingredients can be way too strong for some people. You may not respond well to sulfates if you have sensitive skin or hair, or if you have any allergies or sensitivities to these types of chemicals.

Sulfate-free shampoo is also recommended by the American Academy of Dermatology (AAD) for people with rosacea. This is because the ingredient is found to irritate skin with rosacea and may lead to symptoms on your scalp as well as on your face, shoulders, and back. If you have rosacea, you’ll also want to avoid other known irritants in shampoos such as fragrances, alcohol, and alpha-hydroxy acids like glycolic and lactic acids.

The AAD also says you should avoid sulfates if you have eczema, contact dermatitis, or sensitive skin. Any potential lathering effects from sulfate shampoos could irritate these types of skin conditions.

An allergic reaction is also possible if you’re sensitive to sulfates. If this is the case, you might notice one or more of the following symptoms on your scalp and face after using sulfate shampoo:

  • redness
  • skin rash
  • swelling (inflammation)
  • itchiness
  • hives

You may also want to avoid sulfates if you have dry or fine hair. These hair types are more fragile, and the sudsy effects of sulfate shampoo can strip out too much of the natural oils needed to keep your strands healthy.

Sulfates also might strip out color from your color treatments, though the scientific evidence of such effects is mixed. You might consider choosing sulfate-fee shampoo for color-treated hair to be on the safe side. These may not lather as much, but they help your hair maintain moisture that may be lost from your color treatments, too.

Additionally, sulfates are known to cause hair frizz. When sulfates make contact with your hair, they create a negative electrical charge, which can create frizz after you shampoo. You can minimize these risks by looking for a sulfate shampoo that also has frizz-neutralizing ingredients, such as amphoteric or nonionic surfactants. However, if you’re especially prone to frizz, you might want to skip sulfate shampoo altogether.

Overall, sulfate-free shampoos are more expensive than their conventional sulfate-containing counterparts. But the trade-offs may be worthwhile, especially if you have sensitive skin or hair. Check out some of the following products you can try based on your hair type:

Sulfates don’t necessarily pose health risks for all users. However, if you have a sensitivity to sulfates or if your hair is dry, fine, or damaged, it may be best to choose a different type of shampoo. You might even just prefer to avoid them altogether to be on the safe side.

There are also other things you can do to help keep your hair at its best. Consider following these tips alongside using sulfate-free shampoo:

  • Wash your hair only as often as you need to. Oily hair needs to be cleansed most often, usually on a daily basis. Dry hair may only need to be washed a few times a week; shampooing more frequently could strip natural oils from your hair and make it even drier and more dull-looking.
  • Make sure your shampoo is tailored to your hair type. This includes creamier shampoos for dry and curly hair, color-care products for color-treated hair, and more.
  • Don’t forget to use a conditioner! Shampooing your hair removes excess oil and dirt, but it can also get rid of natural oils. (Think of this as like washing your face, where you always need to follow up with a moisturizer tailored to your skin type.) You always need to follow up with a conditioner, unless you have a 2-in-1 combination product. Concentrate on using the conditioner on the tips and lower half of your strands only.
  • Use heated tools sparingly. The daily use of a hair dryer, curling iron, or flat iron, will eventually damage your strands. Try using them every other day if you must, and use a sulfate-free dry shampoo in between.