So it made me examine my own thumb. I've had these weird longitudinal ridges in all my nails for roughly the last 20 years. I'd blame them on the Wheaties, but I think I've only been eating Wheaties for the last 15 or so.

Attachment 46899

isn't that I Ching? Morse code?

Vertical ridges are fairly common and don't usually signify a health problem. They become more prominent with age. Sorry, glatt - they probably won't disappear anytime soon.

Minifob's toenails were all ridged like that from about age 1 to age 4. We figured it was either a nutritional deficiency or a stubborn fungal infection in the nail bed.

I peeled the nail off my left big toe last winter. It only now looks normalish. I feel bad I didn't document it. Strange deal.

Fungus looks very different. It causes yellowing of the nail and lifts the entire nail; there's a lot of debris between the lifted nail and the nail bed. Very distinctive.

Vertical ridging is common; whether it's due to a nutritional deficiency is impossible to say. It could be due to almost anything - genetic, environmental, and everything else. There isn't enough information out there to say.