Senior citizens can be prone to depression, especially if they're living alone, but using the Internet could stave off that medical issue as well as any feeling of being isolated and lonely, according to new Michigan State University research.

The study, which followed the lives of retired Americans for six years, reveals going online can reduce the chance of depression setting in by more than 30 percent.

"That's a very strong effect," said Shelia Cotten, a Michigan State University professor of telecommunication, information studies and media who led the project. "And it all has to do with older persons being able to communicate, to stay in contact with their social networks, and just not feel lonely."

Cotton and her team analyzed data collected from surveys completed from over 22,000 seniors every two years and feedback from 3,000 seniors. The study considered users' depression levels before Internet use was introduced.

"This is one of the largest and most comprehensive surveys of its kind," Cotten said.

Though some surveyed remained depressed it wasn't a substantial number, according to the study.

 "Internet use continues to reduce depression, even when controlling for that prior depressive state," Cotten said. "This study makes significant contributions to the study of Internet use and depression in the older, retired population."

But the Internet, warns the researchers, isn't a panacea for an active social life involving interaction with friends, family and peers. Moderate Internet use is the best approach, says Cotton.

 "If you sit in front of a computer all day, ignoring the roles you have in life and the things you need to accomplish as part of your daily life, then it's going to have a negative impact on you," Cotten said. "But if you're using it in moderation and you're doing things that enhance your life, then the impacts are likely to be positive in terms of health and well-being."