Yeah, I thought it was genetic, like my crooked pinky finger. My sister's nails look just like mine. Our index and middle finger nails bend down on the side that faces the thumb, on both hands.
I've been taking Iodine for four months and can't say how long I used it before it helped. I just looked down at my hands one day lately and the nails aren't bent anymore. It has to be the Iodine.