Does turmeric change your whole body colour into yellow/light brown( daily user )?

Like anything else, it gets absorbed and split up to serve various bodily functions. Since tha amount used is so small, no effect is likely to be noticed. For comparison, you don't turn green just because you eat lettuce.

Provitamin A is a yellow dye and it will change the color of your skin to orange, but you have to eat an awful lot of carrots to do that.