Currently, I am reading a quite interesting book, "Survival of the Prettiest: The Science of Beauty" by Nancy Etcoff. It is mostly about beauty from an evolutionary perspective, how physical beauty often signals healthy genes and attracts mates.
One section that interested me was the part on hair. Etcoff states that hair, especially long hair, is a record of health so to speak. In ancient times, if one had proper nutrition and overall good health, their hair would appear shiny and bright. This was an important cue used in the mating game.
This point got me to thinking: how did people get healthy-looking hair before all the modern hair care products were available? Is it possible to have healthy hair without any cosmetic products?
One clue in this regard is this link. Apparently, Penny Weynberg hasn't washed her hair in 11 years. While this sounds absurd by modern standards, it may not have been by hunter-gatherer customs. Penny mentions in the article that she believes hair has the ability to clean itself. This would certainly make sense from an evolutionary perspective.
I also read on other sites that shampoo and conditioner produce a vicious cycle of sorts. Shampoo, which is mainly a detergent, strips the hair of its natural oils, and then conditioner artificially puts oils back. Alternatively, these sites say that if you leave your hair alone for a few weeks, the body will naturally produce an equilibrium with the proper amount of oil in your hair. There is no harm in rinsing the hair with water, or brushing through it to remove any debris or dirt.
I'm not completely convinced, but this scenario sure seems plausable to me. Again, the economic incentives are against finding the "truth" (whatever it is) for this issue. Who would have any incentive to tell you if shampoo and conditioner were unnecessary? The manufacturers of shampoo and conditioner certainly would not. Neither would hair salons, who probably make a good bit of revenue from selling hair care products. The only way to find out is to try it and see what happens.
