thumb nail splitting

[dsmall0084]

What does it mean or what can my husband do...his thumbnails have a ridge in center of nail and then it breaks at the end.  It's a v in the center of nail.   He keeps them short but it still breaks.
Thanks Debbie

[Zeumi]

Nutritional deficiencies that show up in the fingernails usually are in both hands and in at least 2-3 fingernails. For example, spoon shaped finger nails that can hold a drop of water. This is called the "water drop test" may indicate an iron deficiency; this has been seen in iron deficient patients on dialysis. White spotting in several nails, both hands may indicate a zinc deficiency.

Changes also can occur from severe health problems that will show up months later as the nail grows out.

If it is only one fingernail it is likely due to some activity or habit or injury like Trialanderror mentioned above.

Stay Heathy, Eat well!

[Trialanderror]

Not an expert but they say it can be a sign of brittle nails, caused either by having the hands in water lengthy times or frequently being in contact with harsh cleaners or chemicals. The nails are dehydrated and need protection or rather a cure with oils applied externally to the cuticle every day. Brittle nails can also peel, I believe there was a question below in regards to this. As far as I know, nutritional deficiencies rather show as uneven surfaces of the nail bed.