Your fingernails grow faster in summer.
744
There are glasses which allow a red-green color-blind person to see colors the way everyone else does.
22
The largest cell in the human body is the female egg and the smallest is the male sperm.
682
Playing Tetris after a traumatic event can prevent the development of traumatic memories and reduce the chance of having flashbacks.
29
The average person's skin weighs twice as much as their brain.
131
Enamel is hardest substance in the human body.
61
After age 30, the brain shrinks a quarter of a percent (0.25%) in mass each year.
139