While you might be close to your friends and family, but you have friends who are closer still. 600 different species of bacteria inhabit your mouth every morning. They’re the little guys that make up that tasty film on your teeth. Yum.
And it doesn’t stop there. About 500 species of bacteria, as well as many species of yeast and other organisms, inhabit your human gastrointestinal tract and make up your “gut flora”.
Yep. You’re a veritable Petri dish of little goo-critters. If you’re an ‘average’ human, the bacteria weigh in at about 1kg and the number of individual micro-organisms easily outnumbers the total number of cells in your bug-loving human body. (So far, none of these organisms have been identified as the midicloreans that Yoda uses to channel The Force but perhaps if you don’t brush your teeth you’ll have a nagging desire to build a light saber.)
Luckily for us a large number of these organisms don’t cause disease — instead, they help protect us from disease. The gut flora perform many functions that contribute to the health of the human host; “friendly bacteria” mostly have names beginning with Lactobacillus or Bifidobacteria.
The friendly bacteria aren’t the only type of microorganism present in your gastrointestinal tract however. There are also a number of organisms that don’t provide you with any benefits; these include coliform bacteria, yeasts and bacteroides.