My finger nails rarely break (unless I try to use them as pliers or screwdrivers) and are in such rude good health that I have to resort to clipping them when they get too long (I credit Bareille's nail strengthener for this). Within days of applying a nail polish - even with an expensive manicure - my nails, flake and break. I've tried polish without formaldehyde (the ingredient that is commonly blamed for drying out nails) without success. So I am very excited to find VB Cosmetics' Dazzle Dry.
This new range of polish claims to be a world first. I don't know about that, but Dazzle Dry certainly looks worth a try. In addition to being formaldehyde free, it has no nitrocellulose (although I haven't been able to find out why I should be glad about this), no phthalate (this does unspeakable things to hormones and is banned from children's toys in Europe), and no toluene (a toxic paint thinner).
I have bought a bottle ($9) in Rose Quartz with the base coat at $12.50. Fingers crossed.