It is normal to lose over 100 strands of hair a day and it isn't necessarily a sign of stress or sickness. This is because hair has a lifespan of five years. (100,000/(365*5) = 54.79)
Hair contains information of everything that has ever been in your bloodstream (for at "most" ~five years).
Other than bone marrow, hair is the fastest growing tissue in the human body (a tissue is an ensemble of similar cells). However, all of your hair is dead, with the exception of the hair in the epidermis of your scalp (the outermost of the 3 layers of your skin).
Healthy hair stretches an additional 30% when it's wet.
At any given time, 10% of your hair is "sleeping" whilst the rest is growing.
Hair is stronger than copper wire (proportionally).
Each hair strand has it's own muscle. These muscles contract when we are scared or cold (gooseb.u.mps).
The same substance that horses hooves are made up of also makes up our hairs (keratin).
Men's hair and women's hair are identical in structure (However, woman shampoo costs more...).
Each hair strand can support 100 grams. This adds up fast leading to insane acrobatic performances. Although together they may be able to support a weight equivalent to 2 elephants, your body would be ripped apart.