A new study finds a link between teens’ exposure to alcohol ads and how much of those brands they drink.

Researchers at Boston University studied more than 1,000 13- to 20-year-olds who said they had consumed alcohol in the past month. Underage drinkers who didn’t see any alcohol ads drank about 14 drinks per month, compared with 33 drinks for those who had seen an average amount of alcohol ads, CNN reports.

The findings appear in the Journal of Studies on Alcohol and Drugs.

“I think one of the implications for the broader society is that currently our controls on television advertising for alcohol are minimal and they’re self-regulatory, so I think we should definitely tighten up that seam,” said lead researcher Timothy Naimi, MD, MPH.