Not sure if you can see in the picture very well, but I've noticed in photos my hair is visibly quite thin. I don't think it used to be this bad but now the parting looks wider and you can definitely see my scalp a bit in pictures. Is there anything I can do to improve its appearance in the short term and also to get it to grow better? I'm only in my thirties and I dread to think how much worse it might get over time! Does castor oil work, or some kind of vitamin supplement?