Wanna not get sick? Wash your hands. Without antibacterial soap.

Everyone knows they're supposed to wash their hands but guess how less often you'll get sick if you do it? A major meta analysis (an analysis that puts together the results from many studies) of 30 different studies from 1960 to 2007 shows you'll reduce gastrointestinal illness by 31% and respiratory illness by 21%. A dataset this huge (and repeated by many different groups), means we can really trust the results.

Practically, if you don't washing your hands and had "stomach flu" three times over the past year, then you start washing your hands, you'll get it only twice. 

Of note, antibacterial soap and ethanol hand sanitizers were not effective. The best method? Good old soap and water! Considering that antibacterials disrupt hormones (might even make your kids fat?) and that young kids can get drunk off hand sanitizer, I think this is a case of simpler is better.