How Shampoo Works: Surfactants and Conditioning Agents

Published on Oct 01, 2013 in Facts

There are so many things we do on a daily basis without thinking. We wake up, brush our teeth, take a shower and go to work. Our routines define us and allow us to live productive lives. Routines very often replace the why with the what. When it comes to showering and washing with shampoo we know the what but not necessarily the why. I mean, what is shampoo exactly? What makes it shampoo as opposed to body wash or hand cleanser? How does shampoo work?

How Does Shampoo Work?

The human head is a wondrous place. Our ancestors used to be covered in hair. Modern humans only have hair in a select few places. The head is the most noticeable. It consists of hundreds of thousands of hairs that all come together to create your hair. The follicles pick up dirt from the environment. There is also sweat and sebum that build up on your scalp and hair. In order to keep your hair and scalp looking and feeling great you have to wash it. That is where shampoo comes in. It is specially formulated with oils and other chemicals that work especially well with hair. Between the surfactants and the conditioning agents your hair is left clean and soft without stripping away too much of the natural sebum oil from the follicles. It is a fine dance.

What Are Surfactants?

Have you ever gotten oil or grease on your hands? If you have you know how frustrating it is to clean it off. You can run all the water in the world over your hands but the oil won’t budge. When you just use water on your head the same thing is happening. The water can wash away the sweat and dirt but the oil remains. Surfactants in the case of shampoos and soaps emulsify with the oils on your head so that they can be washed with water. Some of the widely used surfactants are sodium lauryl sulfate and sodium laureth sulfate. Some people think these chemicals are dangerous but the evidence is inconclusive.

What Are Conditioning Agents?

When we wash our hair we want to get rid of all the dirt and grease. This can sometimes leave our hair dry. That’s why conditioning agents are added to the shampoo. They condition and coat the hair to keep it moisturized and soft. You can use a standalone hair conditioner but most shampoos come with some conditioner in the formula. The conditioning agents also act as a detangler. Because the conditioner lubricates the follicles they can easily untangle making your hair way more manageable than before. The conditioner also helps to prevent static which can make your hair frizzy.

Surfactants in the shampoo clean the hair

Surfactants in the shampoo clean the hair

Additional Ingredients

Many shampoos add their own blend of essential oils to help fortify and replenish the scalp and hair. For instance many dandruff shampoos add tea tree oil because of its anti-bacterial and fungal properties. Fragrance is usually added as well to leave your hair smelling nice. There is something called purple shampoo where purple dye is added to combat brassiness in blond hair.


Shampoo is something we use on nearly a daily basis. It is important to begin to understand what it does and how it does it. There are many different types of shampoo on the market and they all have their own unique formulas. The type of hair you have will effect the type of shampoo you should use. I really only touched the surface on the topic of shampoo but I hope you can now wash with a bit more confidence!