(CBS) Evidence is brewing that coffee can prevent cancer.
The latest study shows that java junkies are significantly less likely to develop head and neck cancer - and the more coffee consumed, the lower the risk.
Those who drank four or more cups of coffee a day were a whopping 39 percent less likely to develop tumors, according to the American Association for Cancer Research, which publishes Cancer Epidemiology, Biomarkers & Prevention, the journal that published the study.
The study, which looked at pooled data from nine previous studies, didn't answer the question of whether decaf had the same anticancer effect as caffeinated coffee. But it found no evidence that drinking tea affects the risk of head and neck cancer.
The study was associative, which means although researchers found a strong link between coffee drinking and reduced cancer risk, they can't say for sure that it's the coffee doing the trick.
"Since coffee is so widely used and there is a relatively high incidence and low survival rate of these forms of cancers, our results have important public health implications that need to be further addressed," said Mia Hashibe, Ph.D., assistant professor in the department of family and preventive medicine at the University of Utah, Salt Lake City, and the lead author of the study.
This isn't the first study to suggest that coffee has an anticancer effect.
Last December, Harvard University researchers presented data showing that coffee consumption lowers the risk of prostate cancer. Men who drank the most coffee were 60 percent less likely to get an aggressive form of the disease than men who didn't drink coffee.
And English researchers recently published a study that found that brain tumors were less common in people who drank at least five cups of coffee or tea a day.
Does light or moderate coffee consumption lower the risk of head and neck cancer? "We didn't see a clear association for the moderate drinkers," Hashibe told Aol Health. "But coffee is a really compex set of chemicals. I wouldn't recommend that everybody drink that much coffee."
But if you do, at least you have something nice to think about as you struggle to fall asleep.