Why does shampoo lather better the second time?

Vananners is vexed…Why does shampoo lather better the second time? Especially with those ‘sulfate-free’ ones. The first time you shampoo it may not lather that well but when you follow up (right away) with a second shampooing the lather is crazy! Also, do you think it’s beneficial to shampoo twice in the shower? I have been doing that lately because I only shampoo about 2-3 times a week and want to get a good, deep clean while I’m doing it.

The Left Brain responds:

Lather is a function of three key variables: the type of surfactant(s) used in the formula, the concentration at which they are used, and the presence of “anti-foam” agents. Anti-foamers are typically oily materials that “use up” some of the surfactants ability to produce lather.

Lather, rinse, repent

The first time you wash your hair you’re removing all (or at least most of) the anti-foamers (dirt and oils) that have built up in your hair since the last time you shampooed. These oily materials reduce how much lather the shampoo can create. (This lather reduction is particularly acute for sulfate-free shampoos because their lathering capacity is lower.) The second time you suds up, you get a lot more lather because the anti-foam agents have been washed away.

Washing your hair twice is not a bad idea but it depends on how dirty your hair is and how much residue from styling products is present. Washing twice may also increase your need to use a conditioner.

How many times do YOU typically wash your hair? Leave a comment and share your shampoo secrets with the rest of the Beauty Brains community.