What diets are there for healthy, soft skin and shiny hair?

Healthy hair. Get adequate sleep,avoid excess sugar & fat, v carbonated drinks, eat enough protein, exercise regularly. Insure you have adequate Iron (like kale & other dark green leafies), Omega 3 fatty acids (like walnuts),vit.E (fruits & veggies), D & B vitamins, biotin & zinc. Avoid sulfates & formaldehyde in shampoos, excessive blow dry heat & curling irons.
Diets for skin. There are no special diets which improve the skin other than what one would ordinarily use for good general health. Diet has almost no effect on the texture of the hair. However, if someone is severely malnourished, hair quality can suffer.