People have always commented on my nice nails - not too long, not too short, normally pale polish or a French, a bit funkier colour if going out. Always clean and cared for. I have never bitten them in my life. But, for about a year now, they seem to have been becoming brittle. They will suddenly just snap off or split if I snag them on something. Is this yet another getting old thing - or is there something I can do about it? I am sure it can't be my diet, as I eat disgustingly healthily, but I am sure I remember reading about some deficiency which causes brittle nails. I have tried googling but I seem to keep finding American sites which suggest some weird pills.