Recent JAMA studies reveal counterintuitive findings: ultra-low THC doses (0.002 mg/kg) show neuroprotection without psychoactive effects, while 4% THC reduces pain but 8% worsens it. Medical users show improved cognition over time, contrasting sharply with the Dunedin study's findings on heavy recreational use. Temperature-controlled vaping at 160-200°C preserves therapeutic terpenes destroyed by combustion.