At our 27th Annual World Congress in Bangkok, we interviewed one of our speakers, Professor Thomas Dawson, on the topic “best shampoos and conditioners”. Dr. Dawson has been a hair researcher for over 20 years, primarily in consumer hair care, and is the CEO of Beauty Care Strategics. He currently leads the “Skin and Hair Health” department at the Skin and Research Institute in Singapore.
In this video, he shares insights from a consumer care scientist’s perspective about hair care and shampoos to maximize hair health, specifically those anyone can buy from a store or salon.
Transcription of Dr. Dawson Discussion in the Video
Because hair is a very complicated structure, many treatments damage it in ways that promote breakage or change the hair’s structure. So hair care products are designed to repair and minimize the damage done by other hair care regimens.

There are three types of hair care products:
- Shampoos
- Rinse off Conditioners
- Leave in Treatments
Shampoos and conditioners are designed to be used with water to rinse them off. This creates the big conundrum: If you want a product to do something to your hair, you want it to leave the active ingredient on your hair, not rinse it off. So “rinse-off” products have a difficult challenge leaving things behind. Shampoos are specifically designed to clean. So it is very difficult for a shampoo to leave behind a benefit agent, whether it is to benefit scalp biology or hair chemistry.
The best recommendation for finding the best shampoo is to find one that cleans. Don’t look for shampoos to condition, leave behind colorants or to repair. Look for shampoos to set your hair up so that it is clean and ready to receive a benefit agent from another product, which in western culture primarily will be from a rinse off conditioner.
While rinse off conditioners have less surfactants and more benefit agents than shampoos, they are very similar. Conditioners are designed to repair the damage done to hair by problems such as weathering, UV from the sun, or chemical and thermal treatments. What they do is leave behind (deposit) specific materials to fix specific problems.
Conditioners are meant to make hair shiny, or in chemical terms, hydrophobic. They are meant to leave materials behind such as slippery materials like silicone or oils that allow you to comb or brush your hair easily without damaging or breaking it.
I am frequently asked about sulfates and “sulfate free” products. Today, there is a huge trend to remove sulfates from shampoos. The desire for “sulfate free” originated from people being sensitive or allergic to sulfates in foods. But topically, sulfates do not seem to have similar toxicity in humans. What people are really looking for in sulfate free shampoos is mildness, or less “chemicals”.
But surfactants are designed to clean and what they are supposed to do is remove things from hair. Removing sulfates from surfactants results in a milder, but less cleansing shampoo. So, when using a sulfate free shampoo, you end up having to use more surfactant in the same shampoo to get adequate lather and cleaning because it is milder and less cleansing.
In conclusion, there isn’t a technical reason to use a sulfate free shampoo. Realistically, the benefit you get is going to be based on the specific formulation you choose. Everyone’s hair type is different, so getting the right shampoo and conditioner for your hair type is more important than using a sulfate free shampoo. Mainly focus your shampoo choice on getting one to clean, leaving your hair ready for the next treatment steps.