Fatty Alcohols in Hair Products: What You Need to Know

We all know that good hair days make us feel on top of the world. We also know that bad hair days can bring our whole day down. That’s why it’s so important to be educated on the ingredients in our hair products!

In this blog post, we will discuss the good and bad alcohols in hair products.

By knowing which alcohols are good for your hair, you can keep your locks moisturized, healthy, and strong.

And by knowing which alcohols are bad for your natural hair, you can avoid product trial and error and save yourself time and money!

Fatty Alcohols in Hair Products

A hair care formulation may include a wide range of different ingredients. There are two major groups of ingredients; active and functional ingredients or additives/fillers.

Both actives and additives are formulated to perform together synergistically to deliver the desired results.

Fatty alcohols are one of the most frequently used and added ingredients in formulations.

These fatty alcohols are used in high amounts and that’s why they are listed within the first few ingredients on the label.

They are often used in conditioners, deep conditioners, masks, styling creams, and pomades.

Types of good alcohols

✓ lauryl alcohol

✓ myristyl alcohol

✓ cetyl alcohol

✓ cetearyl alcohol

✓ stearyl alcohol

✓ behenyl alcohol, etc.

Since they are frequently used in hair care products and in high dosage, it’s important to explore them, their chemistry, usage, and their impact on product texture as well as on hair quality.

So, let’s study this vital class of ingredients and examine its science.

Fatty Alcohols: What are these materials?

Alcohols are organic molecules that have a carbon chain attached to the hydroxyl group.

A good and simple example is “Ethyl Alcohol” which is the major ingredient in alcoholic drinks.

Ethyl alcohol is simple alcohol, having two carbon centers attached to one hydroxyl group, while fatty alcohols have a long carbon chain attached to the same one hydroxyl alcohol.

The figure below demonstrates the chemical structure of different fatty alcohol molecules.

As one can observe, fatty alcohols contain more than 12 carbon units. They are also known as long chain alcohols. The long carbon chain makes these materials solid and waxy.

These fatty alcohols have a high melting point and waxy nature.¹

This is the key feature utilized in personal care formulations, which add body to hair care products.

Fatty alcohols used in hair care products contain only one hydroxyl group (mono-hydric alcohol), however, alcohols having two hydroxyl groups attached to the carbon chain are also available. Glycerine is one of them.

Propylene glycol is another example frequently found in skin and hair care products. Their chemical structure is different and so is their role in the formulation.

Source of Fatty Alcohols

Today, most fatty alcohols used in the personal care industry are sourced from plants.

Natural oils are used as the feedstock to process or extract these fatty alcohols. Coconut oil or palm oil is the major source today due to its abundant availability and large-scale plantation.

These oils contain long-chain fatty acids which are processed to obtain alcohols which are further processed to isolate the desired carbon chain materials.²

Different oils have different chemical compositions and thus have varying proportions of these fatty alcohols.

Today, formulators and consumers both prefer to have a sustainable, green, and environmentally friendly source for these alcohols. That’s why plant-sourced alcohols are in high demand.

Role of Fatty Alcohols in Hair Care Formulations

The main reasons for their addition in hair care formulations

Lubricity and Emollience

The long-chain alcohols lubricate and provide emollience to the hair shaft. The wax molecules bind the hair’s outer surface via weak adhesion, forming a very fine coating at the cuticular layer.

Because of this lubrication, fatty alcohols can reduce the surface friction between the fibers, which is especially important when combing and brushing your hair.

The longer the carbon chain length, the superior the emollience. To put it simply, the higher the number of carbon means higher lubrication.

For example, lauryl alcohol, having the 12 carbon length offers less slip when compared to 22 carbon behenyl alcohol.  

Moisturizing

The hydrophobic coating at the hair surface helps to retain the moisture content of hair fibers.

The long carbon chain minimizes the water evaporation from the scalp or hair. This helps maintain the hair moisture level and thus boosts its quality and natural appearance.

Product texture and viscosity booster

Fatty alcohols are mainly used in emulsion products e.g. cream, conditioners, and pomades.

They provide a characteristic texture and boost the viscosity of the product. That’s why they are commonly termed, bodyfying agents.³

Low carbon alcohol (e.g. lauryl alcohol) is preferred for light-textured formulations, while a thicker creamier texture requires higher carbon chain alcohols.

Bad Alcohols: Drying Alcohols

Bad alcohols are short-chain alcohols that are often used in hair care products.

Why are alcohols bad for your hair?

Some alcohols may have a negative impact on hair.

Ethyl alcohol and isopropyl alcohol are the two alcohols known for their negative effect on hair.

To get an idea of what other products these alcohols are used in, think hand sanitizers and rubbing alcohol.

They are good solvents and help dissolve other ingredients in the formulation.

But their small molecular size also allows them to penetrate the hair shaft and strip away the natural oils, leaving the scalp and hair dry.

Which alcohols are bad for your hair?

✘   Ethyl Alcohol (Also listed as ethanol, denat. Alcohol (2 carbon alcohol)

✘  Propyl alcohol, isopropyl alcohol, propanol (3 carbon unit alcohol)

✘  Butyl alcohol  (4 carbon unit alcohol)

✘ SD alcohol

These alcohols comprise a small carbon chain length and hence are liquid. Applying these bad alcohols on hair will make it dry and frizzy.

This is due to their ability to solubilize oils and lipids. The outer surface of the hair, as well as scalp, contain such lipids and oils. As mentioned earlier, these bad alcohols strip the natural lipids from skin and hair surfaces.

This feature has commonly been observed with hand drying, irritation, or discomfort after using hand sanitizers. That’s why these small chain alcohols are called drying alcohols.

Furthermore, they have a natural tendency to inhibit the growth of microbes. That’s why they are in often used antiseptic and sanitizers formulations.

Moreover, they can also act as preservatives in formulations. Besides this, these small molecules are excellent solvents for hair styling and coloring formulations, because they facilitate the penetration of dye/pigment molecules and improve their fixation on hairs.

Are all alcohols bad for your hair?

The answer is NO.

Alcohols are classified based on their molecular structure i.e., the number of carbons present in their molecular structure.

Miscellaneous alcohols

There are a couple of miscellaneous alcohols that are often used in hair care formulations.

These include:

Benzoic alcohol, which is a non-volatile alcohol. Commonly used as a preservative in cosmetics and should not have an effect your hair texture.

Propylene glycol is an organic alcohol with a molecular structure similar to ethylene glycol (antifreeze).

It’s used as a humectant in hair care products and works by attracting water to the hair shaft.

Butylene glycol is a small organic alcohol used as solvent and conditioning agent. It is often used as a moisture-carrying agent in hair care products. It’s similar to propylene glycol but has a lighter texture.

Final Words

All alcohols are not the same. Long-chain fatty alcohols are excellent moisturizers and emollients for hair while small carbon alcohols are drying and remove hair’s natural oils.

While there are good and bad alcohols for your hair, you know your hair best! So, if you have dry or damaged hair, you may want to steer clear of products that contain drying alcohols.

And if you’re not sure whether an alcohol is good or bad for your hair, check with your stylist or dermatologist. They can help you determine which products are right for your hair type.

As consumers, do your due diligence and thoroughly read the ingredient list.

There’s no need to be concerned about fatty alcohols while drying alcohols should be avoided or at the absolute minimum.

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References

1. Schueller, R.; Romanowski, P., Conditioning Agents for Hair and Skin. Taylor & Francis: 1999.
2. Noweck, K.; Grafahrend, W., Ullmann’s Encyclopedia of Industrial Chemistry. In Fatty Alcohols, John Wiley & Sons: 2003.
3. Zhoh, C.-K.; Lee, K.-Y.; Kim, D.-N., The influences of fatty alcohol and fatty acid on rheological properties of O/W emulsion. Journal of the Society of Cosmetic Scientists of Korea 2009, 35 (2), 103-110.