Dandruff is simply flaking skin. It can flake from being too dry (over-shampooing with the detergents that shampoos are) or under-shampooing, in which case the sebum / oil left on the skin sticks together the usually invisible flakes that always come off the scalp every day. So you can have dry scale from lack of oil if you wash it all away (asteatosis = lack of fat) or you can have oily scale from too much sebum (seborrhea) causing seborrheic dermatitis. This oil is what the Malassezia feeds on, so if you shampoo correctly, the population of M drops because you remove the oily scale. If you over-shampoo, you get dry scalp scale.

I have started rinsing with Kombucha Tea...well old enough that it's now Kombucha vinegar.  My hair is now unbelievably shiny and soft.

Health Man - you are definitely onto something.  I've suffered from dandruff awfully since childhood.  I tried Dr. Mercola's instruction "You can easily treat the dandruff infection by using Selsun Blue, which has selenium in it, and leaving it on your scalp overnight" to end up with 10x the flakes (quarter-sized after treatment - for 8 days straight since it wasn't working at all and I thought I'd perserver - as opposed to the tiny flakes before).  I also ended up with a terrible scalp and hairline irritation.  Also, a whole bunch of my hair fell out!  I've used Neutrogena Coal Tar which makes also my hair fall out like crazy after the recommended application (3-5 min, not all night).  Those commercial shampoos are not the answer.

I'm an avid fan of Dr. Mercola, but I think he's wrong on this one.  I take multi-vitamins & Omega 3's regularly, try to eat mercury-free fish, and use organic extra-virgin coconut oil in my hair 3 nights a week for moisturization.  

I searched the internet, and I found a cure that *finally* worked for me - pure essential oregano oil (make sure you buy the kind that you can apply topically, not the one for aromatherapy).  You're supposed to mix it with olive oil because it's strong (I use organic cold pressed extra virgin) - folks, IT WORKS!  Be patient, it took a full month for my dandruff to clear up, but not a flake since - well not at least for 3 solid months until three weeks ago.  I had stopped using the oregano once my dandruff cleared up.  I'm going back on the oregano for a period of time (it's expensive, be prepared) and I'm going to try out your suggestion.  I'm throwing away my crappy commerical shampoos tonight & I'm buying some natural stuff tomorrow.  Thanks for the tip - it totally makes sense!  BTW I still use the coconut oil intermittently as well - works great as a facial moisturizer too!

Good observation.

Sugar and high glycemic load diet compounds drive up blood sugar, then insulin, then Insulin-like growth factor - 1, then testosterone, then that makes dihydrotestosterone (DHT), that turns on oil glands, so creating more of the oil the Malassezia lives on (and acne besides).

Don't fungi feed on sugars?  This could be the reason your diet affected the dandruff if it is, in fact a fugus!

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