Do people become shorter during the day?

you are not ......... whoever told you this must be on some kind of lethal drugsDo People Actually Get Shorter Late In The Day? Tuesday May 31, 2005
Yes, it's true! The average height of a person decreases, on average, 15mm over the course of the day. This is equal to about a 1% loss of height from morning to evening.

Why does this occur. The answer is that the intervertebral discs, or spinal discs, are composed largely of water. The discs rest between the spinal bones, or vertabrae. These intervertebral disca are compressed as we stand and walk--it is our own body weight that compresses the intervertebral disc. When you sleep at night, the compressive pressure is relieved, and the discs expand again. While the difference is small, it is a fact!