Sofie searches for science: Thanks for running this blog and speaking so clearly about cosmetic chemistry! Having been here for a while, I thought to de-lurk and ask a question. While doing some research and looking around to figure out a better way to take care of my rather coarse, frizzy, curly hair, I came across the Curl Conscious shampoo for thick hair from Bumble & Bumble. They claim that their product contains an enzyme transglutaminase which is supposed to ”cross-link two amino acids in the hair to form stable, heat- and humidity-resistant bonds.” Sounds like exotic-speak for the purpose of shaking out people’s wallets to me, especially considering that amino acids have to already be chemically bonded to each other to make hair protein, but wanted to make sure whether my hunch is right or not.
The Left Brain leads the way
Thanks for your kind words about our blog, Sofie. And I agree that Bumble and Bumble’s claims do sound highly implausible. To find out why, let’s take a look at the science behind transglutamase.
The truth about transglutamase
Transglutamase (or TG) is a type of enzyme that can react with biological tissues. It is involved in the chemical reactions that cross link proteins in hair and skin. Industrially speaking it is perhaps best known for its ability to act as a “meat glue” to improve the texture of processed meat products. It can even be used to create a “meat dress” as pictured above.
Does it have any application in hair care? Yes, in fact, US Patent 6267957 “Attaching Agents to Tissue with Transglutaminase and a Transglutaminase” by Green et. al., discusses the possibility of using TG to alter the structure of hair.
Can Curl Conscious reshape hair?
There are essentially two possible mechanisms by which TG could reshape hair: it could react directly with hair by altering its shape (from straight to wavy or wavy to straight). Or, it could bond thickening or bulking agents to the hair to thicken each individual hair fiber. However, based on its mode of action, it seems very unlikely that TG will have an effect on hair from a shampoo.
The first mechanism seems unlikely because reshaping requires that the hair be held in place in it’s new configuration while the chemical reaction is taking place. (Think of how a permanent wave works: the hair just doesn’t magically become curly, you have to wrap it around a curler of some kind.) The second mechanism doesn’t seem any more realistic because the shampoo is missing other chemicals that are required for that reaction to take place (you can read the patent link above for more details.)
The Beauty Brains bottom line
Curl Conscious may be a perfectly fine shampoo but it appears highly unlikely that the inclusion of transglutamase will have a significant effect on hair structure. My guess is that Bumble and Bumble is making a claim based on what TG can do, not necessarily what it actually does do in their formula. Of course, if they can provide test data showing their shampoo does reshape hair, I’d be happy to reconsider my position.
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What do YOU think? Has anyone in the Beauty Brains community tried Curl Conscious? Or better yet, has anyone ever worn a meat dress?

