Even something as insignificant as fingernails can experience problems. For example, Nails Magazine discusses “longitudinal ridging”, exacerbated by placing the hands in alcohol or water for long periods or by stress from typing or playing piano.
Another difficulty is vertical splitting of the nails. An inconvenience, it is not overly serious. Sometimes fingernails split because the sufferer also has eczema or nail psoriasis. Why, hypothyroid can be a reason fingernails split!
That’s How. Why?
Imagine you have an 8-1/2” x 11” piece of paper used to print a check with a stub above the check. You must “tear along the dotted line”. The perforation weakens the paper so it is easily tears along it. Similarly for some varieties of heavily grained wood. The wood splits along its grain, rather than against it.
Why Fingernails Split: Keratin
Now a fingernail has no perforation. Does it have a grain? In a sense, it does. Fingernails and toenails are made of keratin, a fibrous protein that forms filaments. Where you have filaments along a specific direction, you have a nail grain capable of being split. Given suitable conditions, it will split. Especially when those nails have been weakened.
Some suggested protective measures are enumerated in the American Academy of Dermatology article entitled, “Pinning down the cause of nail problems is the first step to prevention, finding solution”. Of course, results will vary from person to person, depending on the cause of the problem. While it may not be possible to overcome genetics, strong chemicals and abrasives may be avoidable, and restorative or preventive treatments can help as well.
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