Book 2, Question 78
Why Are We a Tiny Bit Taller in the Morning?
Here's a surprise! You are a tiny bit taller when you wake up than when you go to bed. Soft pads between your back bones soak up fluid while you lie down.
From the book
Page from A Million Whys Book 2
More fun facts
- In one study, people were up to 18 millimeters taller right after getting up than later in the day.
- Most of that height is lost in the first four hours after getting out of bed.
- Back in 1724, a minister named Joseph Wasse measured people losing up to 15 millimeters of height during the day.
- Wasse found the shrinking was bigger in young, active workers.
- An old French custom was to sign up for the army first thing in the morning, to look taller.
- Changes in the natural curves of your spine also play a big part in the daily height change.
- After long bed rest or time in space, a person's height can go up by as much as 5 centimeters.
Sources: journals.sagepub.com, newscientist.com, sciencedirect.com
Questions kids ask
Do grown-ups get taller in the morning too?
Yes. Everyone is a little taller after a night's rest, even after they have stopped growing.