Communication about health risks for marijuana use needs to be on-point, especially among young people. From what I've read, use during brain development (prior to ages 25-30) risks learning disabilities and other mental health disorders due to how it affects cortisol. Marijuana is also an immune system suppressor, which may explain some elevated cancer rates. The effects on the immune system may also explain some food allergies, but susceptibility for fungal and viral infections resulting from marijuana use is fairly well established.
Citing some relevant papers on the subject:
https://pmc.ncbi.nlm.nih.gov/articles/PMC8229290/
https://pmc.ncbi.nlm.nih.gov/articles/PMC7258471/
https://pmc.ncbi.nlm.nih.gov/articles/PMC3930618/
https://pmc.ncbi.nlm.nih.gov/articles/PMC4586361/