A new study released this week by the JAMA Psychiatry has shown that long-term cannabis use is associated with few physical health problems in early midlife. The study followed 1,000 New Zealanders from birth to age 38, tracking participants’ self-reported cannabis use from age 18 and those who participated showed no adverse health effects, but they did suffer from poor gum health.

One of the paper's authors, Madeline Meier, explained that she was surprised she didn’t see the association between cannabis and poorer lung function. The study looked at the relationship between cannabis and tobacco users and found marijuana use was related to few physical health issues while tobacco users were associated with multiple issues including worse lung function and metabolic health.

The study brought a team of researchers who assessed periodontal health through clinical attachment loss, which essentially measures the loss of gum support around a tooth. Poor periodontal health increases the risk for tooth loosening and loss. According to the study, 55.6% of those with more than 15 years of regular cannabis use had periodontal disease, compared with 13.5% of those who never used cannabis.

“What we’re seeing is that cannabis may be harmful in some respects, but possibly not in every way,” study co-author Avshalom Caspi said in a news release. “We need to recognize that heavy recreational cannabis use does have some adverse consequences, but overall damage to physical health is not apparent in this study.”