My Husband Has Deep Ridges In His Fingernails And The Nails Also Seem To Have Flatten Out With Age. He Is 65 Years Old. What Are The Health Reasons For This?

The ridges are a sign of possible poor circulation. Make sure to stretch your arms and your wrists to keep them flexible and he will also be less likely to pull a muscle. There may be other reasons but I'm not sure what they are. As for the flattening of the nail I am unsure.

I would consult a physician. I think you can call your doctor and ask questions without having to go in to. Unless they feel with talking with you that a visit is needed.