I've had long, thicky wavy hair since I was a child which turns into a frizz bonnet, as soon as I hit damp weather. I've been sold endless products that 'cure' it. Nothing worked.
Three months ago I had the keratin treatment and it worked beautifully. But like everyone else I was told to avoid any hair products with parabems or sulfates, so I've been using DGJ organics for hangover hair. Daft name but I like the smell of lavender and only shampoo my hair once. I sometimes add wine vinegar to the final rinse. I also use a parabem free deep conditioner every few weeks. My point is that the keratin treatment must have worn off by now but my hair is still frizz free. I can let it dry naturally and it looks wavy but with all the frizz gone. Or I spend ten minutes with my Babyliss brush to give it that just blowdried look which lasts through rain and damp. In my case it was all those poxy parabems and sulfates.
Swish swish!