Read online claims of adults way past puberty growing taller. any truth to that? can a 40yo grow nearly 3 inches out of the blue w/o any explanation?

Acromegaly: Acromegaly is a condition caused by a benign pituitary tumor which secretes growth hormone. It can cause growth of the hands, feet, and increasing height in middle age. The diagnosis could be made by an endocrinologist.

No: The hormones that trigger puberty cause the growth centers in long bones to finish and close. In the rare cases of a growth hormone secreting tumor the puberty never ends/but these patients are not normal adults.Their jaws grow out as do their hands & internal organs. They often die of age related complications before the age of 40.