why do fingernails curl under
But in general, if your fingernails are strong, but curling this is less of a concern than if they are weak and âbendyâ. Specifically: Curling down is very much associated with respiratory problems- asthma, chronic bronchitis, emphysema and the like. Iron deficiency will produce pale nails which can curl.
1. Respiratory Health Issues. Downward curved fingernails can indicate a problem with respiratory health, and are often present in people who have medical conditions such as COPD, chronic bronchitis, asthma and lung cancer. Fingernails often curve downwards as a result of lack of oxygen.