Everything we do effects us in one way or another. We attempt to choose what we want to influence our minds and, as a result, our general well being. Everything we read or watch or listen to, it all effects the way we exist. They make our bodies and minds work in ways that our bodies and minds have evolved to work under such influences. Drugs, taken consciously, are an influence to be considered alongside everything we do and experience.
Food is an influence.
We eat some foods, we grow healthier. We eat some foods, we get sick. We eat some foods, we experience great pleasure. We take some drugs, we grow healthier. We take some drugs, we get sick.