Are people actually taller in the morning?

Martha Talks Back: Reader Questions Answered
by Martha Brockenbrough
Dear Martha,

My brother--don't ask me why--measured his height the other morning and compared it to his height before he went to sleep. He was more than 1/2 inch taller when he awoke! I didn't believe him, so I did it myself, and it seems to work. Are we genetically weird, delusional, or does this work for everyone? And WHY?

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