We all want to live a long, healthy life but let's face it: the good things in life are always the worst for us. After taking a nutrition class where we learned about a group of people in Greece who, on average, live longer than anyone else in the world, I became curious. I researched and watched interviews of centenarians from across the world to find out their secrets to living to 100, and here is what I found:

Jessie Gallan, who lived to 109, claimed that avoiding men contributed greatly to her life of longevity. She told the Daily Mail, "They're more trouble than they're worth." Gallan never married.

Gertrude Weaver lived to an astonishing 116 years old. Gertrude's advice for a long life includes being nice to others and treating them how you would want to be treated. She also never drank or smoked, and slept eight hours each night.

111-year-old Alexander Imich told NBC New York he abstained from alcohol and committed to eating healthy with a diet of chicken and fish. Imich also lived in New York City. In fact, a majority of the oldest citizens in the U.S. live in cities and other urban areas. Approximately 85.7 percent of centenarians lived in urban areas in 2010. Urban areas offer more mental stimulation, better access to high-quality hospitals and doctors, and more social networking.

So, in summary: avoid men and booze, eat a healthy diet, be nice to others, live in a city and get eight hours of sleep a night.