Yawns are more contagious among people with closer relationships.
163
It takes about 20 seconds for a red blood cell to circle the whole body.
102
The human brain uses approximately as much energy as a 10 watt light bulb.
120
Every year your body replaces 98% of your atoms.
119
After age 30, the brain begins to lose about 50,000 neurons per day - shrinking the brain .25% each year.
55
If you are cold you are more likely to be hungry because you use energy to keep warm.
143
It takes twice as long to lose new muscle if you stop working out than it did to gain it.
127