Snus, a moist, smokeless tobacco product, may contribute to breathing and sleep problems, according to a study by Swedish researchers reported by Reuters.

Based on questionnaires answered by more than 16,000 never-smokers in Sweden, researchers found that snus users were over 50% more likely than non-users to have asthma. In addition, snus users were 37 to 59% more likely to snore and have trouble falling asleep, the study found.

Participants who reported having any respiratory symptoms were more likely to be smokers and dual users of cigarettes and snus. However, snus users were more likely to suffer from wheezing and night-time chest tightness, chronic bronchitis, and chronic nose and sinus problems, when compared with participants who were completely tobacco-free.

The study team also found that people who reported having asthma were more likely to be current snus users and the same link wasn’t seen among past snus users, dual users or people who only smoked.