Soon after I started my hair loss research, I repeatedly came across the suggestion that going without shampoo for a prolonged period of time is healthy for your hair.
The reasoning behind this idea is that your body will, after about six weeks, restore balance to the level of sebum (oil) produced by the sebaceous glands inside the hair follicles (see diagram below).
For most people (including myself) this would mean a reduction in sebum rather than an increase. That's because, if you suffer hair loss, sebum and dihydrotestosterone (DHT) levels in the affected region of the scalp will become excessively high.
At first I thought this radical approach to hair hygiene seemed ridiculous. Most of us are exposed to pollutants virtually every day (exhaust fumes, chemicals in foods, cleaning agents, cosmetic products, etc). So I considered using shampoo every single day as a sensible measure. After all, we wash every other part of the body on a daily basis, so why not the hair?
Furthermore, other research suggested that a clean scalp encourages hair growth, whilst a scalp clogged up with sebum, dirt, etc will not.
However, given that sebum production is controlled by DHT (a hormone definitively linked to hair loss) I wondered whether DHT levels could be "down regulated" (reduced) using this approach. In other words, if my hair follicles got all clogged up with sebum, after a while would the sebaceous glands eventually get the message to decrease production? And, in turn, would this also reduce DHT levels?
I decided it was worth finding out the answers to these questions. So I performed this experiment for six weeks.
Within 48 hours, my hair, scalp and follicles were all clogged up with sebum. I wanted to quit of course (everyone does when they first try this sort of thing). But I persevered for the full six weeks.
So, did it work?