I heard you aren't supposed to wash you hair everyday But after one day my hair is already oily. Why
Some people just produce more oil than others, for instance if your hair is straight you're more likely to have that oil hair look versus if your hair is curly then most times its very dry because the oil can't get around the curly hair like it does when the hair is straight. For some people washing the hair everyday can be drying to the scalp if some of the oil isn't replaced. With that being said, if your hair is excessively oily after one day of having been washed then it may be necessary for you to wash that often. On the other hand, if its a moderate amount of oil then skip a day, having some oil isn't all bad.
that's a myth , try a powerful but gentle shampoo - I switched as some suggested on site to Scientific Essentias and locked in moisture and oils to cuticle as it says. Excess oil outside needs to be removed but the key is locking in hairs properties for protection
it also may be the products you're using to cleanse stimulate oil production due to various surfactants or sulfates in the products. Hormone