Thanks so much for writing to us here at TruthBook with your question.
The passages that immediately come to mind in regards to this issue are:
110:6.4 It is to the mind of perfect poise, housed in a body of clean habits, stabilized neural energies, and balanced chemical function — when the physical, mental, and spiritual powers are in triune harmony of development — that a maximum of light and truth can be imparted with a minimum of temporal danger or risk to the real welfare of such a being. By such a balanced growth does man ascend the circles of planetary progression one by one, from the seventh to the first.
110:1.5 The Adjuster remains with you in all disaster and through every sickness which does not wholly destroy the mentality. But how unkind knowingly to defile or otherwise deliberately to pollute the physical body, which must serve as the earthly tabernacle of this marvelous gift from God. All physical poisons greatly retard the efforts of the Adjuster to exalt the material mind, while the mental poisons of fear, anger, envy, jealousy, suspicion, and intolerance likewise tremendously interfere with the spiritual progress of the evolving soul.
Now, the evaluation of what constitutes "clean habits," and what constitutes "physical poisons" change from time to time. I suppose that most people would classify cigarettes as a physical poison these days (and I might add alcohol, too), but as for marijuana – which used to be classified as a dangerous drug – the conventional wisdom has evolved. Nowadays, clinical and scientific research have revealed heretofore hidden health benefits that marijuana provides. In fact, marijuana has been decriminalized in several American states, with more states expected to follow suit in the future. So, what may have been true at one time may change as a result of further research
These other kinds of poisons that are mentioned: fear, anger, envy, jealousy, suspicion, and intolerance, are mental poisons. Much more is said about them-and overcoming them-throughout the text than any mention of physical poisons, and all of these are just as harmful (spiritually) as the physical poisons in question.
It occurs to me that overcoming some of these so-called mental poisons may help alleviate a person's "need" for physical substances in the long run. I am thinking specifically of the mental poisons of fear and anger, which can really distort peoples' minds and may prompt them to seek relief in a substance of some sort...that's just my opinion, though.
Thanks so much for this question. I hope that my reply has been helpful.