If we see a new warning label on alcohol, are we less likely to buy it?

Every bottle of alcohol sold in the U.S. has a warning label, which says pregnant women should avoid alcohol, that drinking can impair your ability to drive a car, plus a vague mention that alcohol “may cause health problems.”

On Friday, the U.S. Surgeon General recommended big changes to that label, including making it more visible to consumers and adding specific information on how alcohol can cause certain kinds of cancer.

More than 70% of adults in the U.S. have at least one drink a week, according to the Surgeon General advisory. At the same time, less than half of all adults are aware that alcohol causes cancer.

“There is a knowledge gap,” acknowledged Jürgen Rehm, a professor of public health and psychiatry at the University of Toronto.

One thing that would help close that gap is a big prominent warning label on every bottle, he said. “‘Alcohol causes cancer’–like that, people will immediately realize that this is the case.”

And there’s research that shows that when people see alcohol and cancer together on a warning label, they’ll buy less of that alcohol.

“We know that warning labels can reduce consumption to some extent,” said Dr. Tim Naimi, who directs the Canadian Institute for Substance Use Research at the University of Victoria.

He points to a study in Canada’s Yukon territory that found when large colorful labels were added to bottles of alcohol warning it can cause cancer, per capita sales of labeled products went down by more than 6%.

A lot of people drink because it’s a habit, Naimi said, and a new warning label might make them change that habit. “You know, does it mean we’re going to stop drinking? No, but it might mean that we–‘you know what, instead of buying a six pack, I’ll buy two or three cans of something.’ “

What those warnings look like and where they’re placed is important.

“How big are those warnings in relation to the size of the label? What color are they? It’s often more effective to have rotating messages instead of the same one, the size of the font,” Naimi said. “All that stuff matters.”

Images can be especially effective in helping a label get noticed, according to Chapel Hill professor Seth Noar. He’s done research around warning labels for tobacco products and points out that over 130 countries now have what are called “pictorial warnings” on labels for cigarettes.

“They elicit negative emotion,” he said. “They get people kind of riled up.”

It’s one thing to know cigarettes can cause lung cancer, Noar said; it’s another to see a picture of a diseased lung.

No matter how effective a warning is initially, Noar added that it needs to get changed up. “When you see something again and again and again, you just eventually start tuning it out,” he said.

And that current label on wine, beer, and liquor in the U.S.? It’s remain unchanged since it was first introduced in 1988.