The best way to prevent dry hair is to not shampoo every day. I shampoo every other day or every two days, and that seems to keep my hair ok. But I dye my hair frequently, which kills it, and for that I use the Neutrogena Triple Moisture deep conditioner... it's soooo good. Also, the John Freida Deep Conditioner works wonders... I leave it in my hair for like 20+ min and it comes out unbelievable!