Lejla must know mousse: I have fine hair and have been using the Sebastian Body Double Thickify Styler which is a volume mousse. I like the way it makes my hair feel more stiff and sturdy. But why does it say I need to blow dry my hair for it to work? Isn’t that damaging? I’ve also used the more affordable Tresemme “Volume & Lift” mousse, but I just don’t seem to get the same effect. Why not?

The Right Brain replies:
Lejla, good questions. Hopefully the following mousse manifesto will provide some helpful answers.

History of mousse

Like Champagne, mousse is an invention of the French. The fluffy foam was introduced in Europe (by L’Oreal) in the early 1980s and brought to the US a few years later by Tresemme. Over the last 20 years, mousse has grown to be one of the top styling forms along side hairspray and gel.

Types of mousse

There are many kinds of mousse but they all have one thing in common: foam. They may be formulated to provide hold or conditioning and they can be packaged in aerosol or nonaerosol containers. Traditionally, true mousses are aerosols while the nonaerosol type may go by other names like “foam stylers.” Mousses are used to give hair volume and they’re generally combined with some kind of finishing spray to lock the hair into place.

Ingredients

Solvents

Water and alcohol are used to disperse the other ingredients in the formula. (Many mousses are now alcohol free.)

Propellant

The gaseous stuff that pushes the product out of the can. This gas is also what causes the liquid mousse to turn all foamy. Only in aerosol mousses, like the Tresemme product you asked about have propellant. The Body Double product is a non-aerosol mousse that uses a pump to create foam instead of aerosol propellant. There’s no propellant to worry about but the foam is not as rich.

Hold and conditioning agents

These ingredients have the most effect on your hair. They’re a combination of hairspray-like polymers, oils, and other smoothing agents that coat the hair shaft.

For example, Sebastian’s Body Double uses VP/VA copolymer, cetrimonium chloride, polyquaternium-10, polyquaternium-37, and amodimethicone. On the other hand Tresemmé “Volume & Lift” uses these:
acrylates copolymer, VP/VA copolymer, polyquaternium-4, peg-12 dimethicone, amodimethicone, peg-40 hydrogenated castor oil, and cetrimonium chloride.

Control agents

Sets the pH, helps with product stability, and preserves against microbial bugs.

Fragrance

Pretty much what you’d expect - smells pretty.

How Mousse works

Mousse is usually worked through damp hair. As it dries, the polymers and other coating agents set up a film on your hair strands. Unlike hairsprays that “glue” different hair fibers together, mousse is meant to coat each fiber to give it some stiffness. As the film dries, each hair pushes out against the hair next to it so overall your hair is left with more volume. Depending on the type of mousse, your hair can feel very conditioned or stiff and crunchy. (That’s the kind of difference you see between Sebastian and Tresemme.)

Depending on the formula and the amount of hair you have, blow drying may be necessary to get the style that you like. And yes, blow drying can be damaging. It’s a sacrifice you may have to make to get your hair to look like you want it to.