Can you stand on 1 foot for 10 seconds? Go ahead, try it. If the answer is yes , the odds are good that you will live 7 more years. If the answer is no , the odds are still good that you will live 7 more years, but not quite as good. If you’ve already tried this in the past month, you’re not alone. In June, the news wires got ahold of a study out of Brazil reporti...