BIOL 1310: Human Biology

National Heart, Lung and Blood Institute

"Gut instinct”, “misery guts”, “guts for garters”, “gut wrenching”... we’ve been obsessed with it for centuries, but increasing evidence proves a healthy gut plays a crucial role in a healthy body & mind.

Imagine if you had an extra organ with 10 times as many cells as the rest of your body, and that organ affected everything from your digestion to your mood. It turns out you do have something like that, and it's made up of all the tiny life forms that live in your body's nooks and crannies.

Your body can play host to anywhere from 30 to 50 trillion bacterial cells, the most species of which are in your gut. Learn how gut microbiota help us metabolize food and drugs, and defend us against pathogens. Put simply: these microbes are fellow travelers in human evolution.

We spend millions of dollars each year on products that we’re told are good for us. The promise of improving health is the ultimate marketing ploy. But does the science behind this multi-million-dollar business really back up the claims? Using the latest scientific knowledge, this film debunks the fallacies that dictate our choices.