Unfortunately, we don’t know as much about cancer as we would like to. But luckily, one study is shedding some light on one interesting aspect of how cancer occurs in many people.

According to a new study from the journal Nature, cancer is overwhelmingly a result of environmental factors and not largely down to “bad luck” or other factors that aren’t necessarily predictable.

female scientist performing experiment

The study used four approaches to determine that between 10% and 30% of cancers were down to the way the bodily normally functions—what we would qualify as “luck.” Therefore, that means that 70% to 90% of those cancers did have a predictable element to them.

Experts say that this analysis proves to be “pretty convincing.”

Cancer is a curious thing. In January, a report in the journal Science tried to explain why some tissues were more vulnerable (some millions of times more than others) to develop cancer. The rationale was that the number of times a cell divides was a factor, which gave rise to the “bad luck” hypothesis. The new study will change this train of thought.

Luck can obviously still play a factor, but Dr. Yusuf Hannun, the director of Stony Brook, explained the situation perfectly to BBC News: “External factors play a big role, and people cannot hide behind bad luck. They can’t smoke and say it’s bad luck if they have cancer. It is like a revolver, intrinsic risk is one bullet. If you’re playing Russian roulette, then maybe one in six will get cancer—that’s just intrinsic bad luck,” he explains. “However, what a smoker does is add two or three more bullets to that revolver. And now, they pull the trigger.”

Hopefully, more information about how cancer forms and what we can do to mitigate the likelihood of having cancer will lead to a healthier and happier society—this study is a perfect starting point!