This article via NaturallyCurly.com gives some insight as to how to differentiate harmful and necessary alcohols in hair products. Just like bacteria not all strains are harmful.
“Instead of asking “Is alcohol bad for my hair?”, it’s probably better to ask “Are alcohols bad for my hair?” Alcohol is not one chemical but a whole family of chemicals with very different properties and very different effects on your hair. You might have heard that alcohol is bad for your hair. As with so many other things, it’s not so simple. It depends on what type of alcohol we are talking about. An alcohol that would be used in a holding spray is probably not going to be great for your hair. However, even these alcohols serve a purpose. Some alcohols are completely the opposite. They are actually “fatty” alcohols that add moisture to the hair by pulling in moisture from the air (they’re called hygroscopic). They also help to thicken products are are not harmful to your hair.
Short chain alcohols are generally the ones coily haired women are going to want to avoid. They are generally used in styling/finishing products. The reason they are used is, because of the way they are structured, they evaporate quickly. But, they also tend to wick moisture away from the hair which can leave it dry and frizzy – usually the very thing curly haired women are trying to avoid. Some examples are SD Alcohol 40, Ethanol or Ethyl Alchohol, Propyl Alocohol and Isopropyl. When many people think of alcohol, they think of rubbing alcohol (isopropyl alcohol), which we all know evaporates quickly. And, it’s true that using these types of alcohols on the hair over and over and not properly replacing the moisture is going to cause damage.
However, there is a completely different class of alcohols. These are large molecule, long chain alcohols that are as different from the short chain alcohols as night is from day. They tend to be “fatty”, clump together and do not evaporate quickly. They draw moisture into the hair, thicken products and are used in some of the best products available for your hair. Examples include Stearyl Alcohol, Cetearyl Alcohol and Myristyl alcohol.
So, the next time you see the word alcohol on the label of a product you’re checking out, do some research on the type of alcohol it is. The type of product will give you a good clue. If it’s a product designed to be used on dry hair as a finishing product, it’s probably a short chain alcohol and will be drying to your hair. That doesn’t mean you can’t use the product. Just understand what it’s doing. If you find alcohols in your conditioner, they are most likely long chain alcohols and they’re being used to benefit your hair. Feel comfortable knowing you’re doing something good for your hair by using it. If you prefer to avoid alcohols altogether by using stylers and conditioners that are alcohol-free, try the Treasured Locks Pomade & Gel and the Awaken Emu Oil Conditioner. Both are packed with natural ingredients that you can feel fully confident applying to your curls, such as aloe vera, shea butter, kosher vegetable glycerin and lemongrass.
The ingredients that your hair thrives under will be unique to your individual curls, but no matter what hair type you have it pays to get well acquainted with your product labels.”-NaturallyCurly.com