A new study reveals that between 20 to 40 percent of U.S. cancer cases and almost half of cancer deaths among white people are preventable by adopting a "healthy lifestyle pattern." Effective lifestyle modifications include avoiding smoking and drinking, as well as maintaining a health body mass index (BMI) and committing to regular exercise.

In particular, the study defined a healthy lifestyle pattern as the following: never smoking or past smoking, no alcohol consumption or moderate consumption, a BMI between 18.5 and 27.5; and 150 minutes of moderate intensity aerobic physical activity or 75 minutes of vigorous intensity.

The researchers examined 89,571 women and 46,399 men, and everyone in the study that met the above four criteria fell into the low risk category for cancer, while everyone else fell into the high risk category. Overall, 16,531 women and 11,731 men made up the low risk group, and 73,040 women and 34,608 men made up the high risk group.

Furthermore, the team determined the population-attributable risk (PAR), which is the number of cancer cases that could be avoided if every individual in the study adopted the aforementioned health lifestyle pattern. The results revealed that between 20 to 40 percent of cancer cases and nearly half of the deaths could be prevented.

Although the study only examined white individuals, other research has suggested the presence of similar risk factors in other ethnic groups. Further research will need to be conducted to determine the exact nature of these factors in diverse ethnic groups and their response to a health lifestyle pattern.

"These findings reinforce the predominate importance of lifestyle factors in determining cancer risk," the authors wrote. "Therefore, primary prevention should remain a priority for cancer control."

"We have a history of long delays from discovery to translating knowledge to practice," wrote Graham Colditz and Siobhan Sutcliffe of the Washington University School of Medicine in an opinion piece on the findings. "As a society, we need to avoid procrastination induced by thoughts that chance drives all cancer risk or that new medical discoveries are needed to make major gains against cancer, and instead we must embrace the opportunity to reduce our collective cancer toll by implementing effective prevention strategies and changing the way we live."

"It is these efforts that will be our fastest return on past investments in cancer research over the coming decades," they added.

The findings were published in the May 19 issue of JAMA Oncology.