…when I’m in the shower or swimming? Every time I’m done with either activity, I always notice that my fingernails and toenails seem to be a bit longer. That is, the white portion at the end seems to have grown.
Why would such a thing occur?
The nails aren’t growing; the skin around them is shrinking away from them.
werewolfism
WAG: the skin at the tip of the nail absorbs water and becomes translucent, making the nail more visible.
It’s the same reason for thinking that hair and nails continue to grow on cadavers: they don’t. The skin does in fact shrink back.
The wrinkling in fingers after immersion in fresh water is swelling. Google away on it if you like, the skin doesn’t shrink back.
Because they’re getting clean, of course.
(yes, this is a joke)
The tips or the quick?
I think this is observation bias. Your nails grow steadly throughout the day, but you only notice them after showering/swimming.