(PhysOrg.com) -- With the new year approaching, millions of people are expected to ring in 2009 by making resolutions to improve their lives. A Duke University researcher says the consequences of some personal decisions provide important reasons to stick to those vows in the coming year.

New research conducted by Ralph L. Keeney of Duke’s Fuqua School of Business, concludes that personal decisions lead to more than one million premature deaths annually in the U.S.

Keeney’s work, published in the current issue of the INFORMS journal Operations Research, shows that personal decisions are the leading cause of death in the U.S. if one takes into account the role of obesity and smoking in creating heart disease and cancer, the primary causes of death in the U.S.

"Previous researchers have identified the main causes of heart disease and cancer as smoking and being overweight, each of which results in over 400,000 deaths annually," Keeney said.

With the number of personal choices made in a given day, many individuals don’t take a step back to look at the long-term implications of those choices, Keeney said. From having unprotected sex to not buckling the seatbelt before driving, many of these decisions can eventually result in death. Other personal decisions that lead to significant premature deaths include overconsumption of alcohol, reckless driving, homicide and suicide.

Keeney’s results showed that more than 55 percent of all deaths for individuals aged 15 to 64 can be attributed to personal decisions that have readily available alternatives.

"Given that the impacts of smoking and being overweight start taking a heavy toll in the mid-30s, I wasn't surprised with this result for people over 35," Keeney said. "However, I was surprised that more than 55 percent of the deaths to individuals 15 to 24 years old could be avoided with different easy-to-make personal decisions. For many of these individuals, more than 40 years of potential productive life is lost."

Keeney said individuals have a great deal of control over their own mortality. His research also shows that individuals don’t always need to rely on others, including government, hospitals and nonprofit organizations, to make their lives safer, because they can easily take effective action to make their own lives and those of their families safer.

Common sense lifesaving choices include: avoiding smoking, drinking alcohol in moderation, exercising regularly, driving sober and abiding by the speed limit, not using illicit drugs and practicing safe sex.

Provided by Duke University