Regular consumption of nicotine also reduces Alzheimer's risk (and probably Parkinson's). This has been known for a long time. Few things are absolute.

1991: https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC1670208/

> The risk of Alzheimer's disease decreased with increasing daily number of cigarettes smoked before onset of disease (relative risk 0.3 in those smoking greater than 21/day v 1 in non-smokers). In six families in which the disease was apparently inherited as an autosomal dominant disorder, the mean age of onset was 4.17 years later in smoking patients than in non-smoking patients from the same family (p = 0.03).

There is also ongoing research on this topic funded by the US government.

https://www.alzheimers.gov/clinical-trials/memory-improvemen...

Nit: that study is cigarettes. There is more to tobacco than nicotine, such as harmala alkaloids and miscellaneous MAOIs.

Either way, that's super interesting.

The addiction is one of the most difficult to quit. With repeated use the nice feelings stop as well. There's no benefit to it, you're hijacking some neural circuitry until it hijacks your life