Marijuana Use May Raise Lung Cancer Risk, Researchers Warn

New Keck Medicine of USC research suggests heavy marijuana smoking may be linked to higher risks of lung and head and neck cancers.

Experts say the evidence is stronger for heavy smoking than for occasional use, and the dose-response relationship is still being studied.

Risks from edibles, other non-smoking forms of cannabis, and secondhand exposure remain unclear.

The findings add to concerns that long-term cannabis smoking could carry serious health risks as legalization expands.