@discographer-- Wow, I have never cooked with macadamia oil before. I think the one I have is food grade so I might try that sometime.
I use macadamia oil as a hair oil. It's great for dry, coarse hair. Just as it moisturizes skin, it also moisturizes hair and makes hair soft and shiny. I apply the oil all over my hair once or twice a week. I put a cap on and leave it like that for several hours while I do house chores. Then I wash and shampoo like usual. I think macadamia oil is a better hair treatment than the expensive treatments at salons. It works great.