In general, vertical ridges are from ageing and are normal.
Thin fingernails as well, although there can be nutrient issues.
If splitting at all, iron deficiency is a common problem.
This is also a problem of ageing along with vitamin D and B vitamins.
These should all be measured along with examination of the nails.
In this instance, supplementation might help.
Of course, vitamins are over the counter, but it is better to have the lab measurements done.
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