|MadSci Network: Medicine|
A very good question. I am sorry for the delay in answering the question. The scientific term for what you are describing is ONYCHOSCHIZIA. It is a vvery common problem and occurs in women more than men. The term includes splitting, frail, soft or thin nails and ridges. The most common cause is repetitive and prolonged wetting and drying of the nails. Trauma to the fingers is also a cause. Using nail polish remover can cause it as well. In some cases, abnormal fingernails may indicate a systemic disease such as one involving the heart or lungs. Some people may inherit their nails from their parents. Another cause could be vitamin or nutritional deficiency - that would be rare in our country. I hope this helps.
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