why we like unhealthy food.

http://www.livescience.com/history/080208-hn-sugar.html

Many of us humans die of obesity caused heart disease every year. Mainly because our bodies prefer unhealthy food. But why?
When we were cavemen, the swet fruits were more nutritious, so we generally preffered the sweet taste. The brain also need glucose to function. Unfortunantly, this later led to us growing sugar cane and developing type 2 diabetes to satisfy our sweet teeth.

people carry millions of bacteria. and they are nice!

This research is part of an emerging effort to study human microbial ecology. Dr. Blaser's laboratory has previously examined the bacterial population in the stomach and the esophagus. "Many of the bacteria of the human body are still unknown," he says. "We all live with bacteria all our lives and occasionally we smile, so they're not that bad for us."

The most numerous cells in our body are microbial--they outnumber our cells 10 to 1. The body has microbes native to the body, including the skin, and these populations change according to how we live, he says. "Ultimately what we want to do is compare disease and health," says Dr. Blaser. Keeping bacterial populations in our body stable may be part of staying healthy, he says.

so, don't goop on all that sanitizer because bacteria are as important as human cells

Running makes people high

When person runs, swims, cycles and performs any other strenuous exercise, pituitary gland releases endorphins: chemicals that release feeling of euphoria and that block sensations of pain. Endorphins are very closely linked to addictions, they were even discovered by accident when scientists were carrying out research on addictions and drugs. Researchers discovered that human brain contains its own neuro-chemicals, which are far more potent than heroin, opium and morphine. They also discovered that endorphins release in times of stress – in case of runners: after strenuous running. Endorphins make runner feel great after exercise and this effect is often referred as 'runner's high'. And it doesn't stop there: endorphins are also motivational. They namely help runner to feel energized throughout their whole day.

so... I think thats why people like to run

if you are ever kidnapped this will be useful