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这是一篇涉及“物质滥用”的文章。

tobacco

cocaine

Technically, any substance other than food that alters our bodily or mental functioning is a drug. Many people mistakenly believe the term drug refers only to some sort of medicine or an illegal chemical taken by drug addicts. They don't realize that familiar substances such as alcohol and tobacco are also drugs. This is why the more neutral term substance is now used by many physicians and psychologists. The phrase 'substance abuse' is often used instead of 'drug abuse' to make clear that substances such as alcohol and tobacco can be just as harmfully misused as heroin and cocaine.
从专业角度说，除食品外，任何能改变我们生理和心理机能的物质都是药物。很多人错误地认为“药物”一词仅仅指某些药品或是吸毒者服用的违禁化学品。他们没有意识到诸如酒精、烟草这些我们熟悉的物质也是药物。这就是为什么现在许多内科医生和心理学家使用“物质”这个更加中性的词。他们常用“物质滥用”而不用“药物滥用”来清楚表示滥用酒精、烟草这样的物质可能如同滥用海洛因和可卡因一样有害。