Cannabis is a substance that is shrouded in myth, paradox, and controversy. On the one hand, a host of literature indicates detrimental effects on areas such as mental health (eg, increased risk of schizophrenia and poorer prognosis among patients with psychiatric disorders who also use cannabis), risk of addiction, and psychosocial functioning.^{,  ,  ,}  On the other hand, there has been an increase in public perception of cannabis as relatively harmless, as well as international movements to legalise cannabis for medicinal or recreational purposes. Of course, this does not necessarily constitute a paradox—benzodiazepines and opioids are also used both recreationally and medicinally, and with both positive (eg, reduction of pain or anxiety) and negative (eg, addiction or death) effects.

中文翻译：

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Δ9-四氢大麻酚：即使低剂量也有害吗？

大麻是笼罩在神话，悖论和争议中的物质。一方面，大量文献表明了对精神健康等领域的不利影响（例如，精神分裂症的风险增加以及也使用大麻的精神病患者的预后较差），成瘾的风险和社会心理功能。^{，  ，  ，} 在另一方面，已经增加了大麻的公众认知的相对无害的，以及国际运动合法化大麻用于医疗或娱乐目的。当然，这不一定构成矛盾。苯并二氮杂和阿片类药物也可以在娱乐和医学上使用，并且具有积极的作用（例如，减轻疼痛或焦虑）和消极的作用（例如，成瘾或死亡）。