Cutting wheat reduced mine a ton and just washing my hair with a mild anti-dandruff shampoo keeps it at bay, though it tends to get worse in the winter or if my hair grows too long. I no longer use ketoconazole/nizoral as it really dried my scalp/hair and it doesn't cure anything at the end of the day since it always comes back.

The only thing I've found that fixes it for some time, is going to THE BEACH. The combination of salty water + sun gets rid of it for months, but it comes back eventually when winter rears its head.

So yeah if you can live near a beach all year round maybe it'll fix it.