A 2021 human twin study investigated epigenetic clocks:

“This study showed that accelerated epigenetic aging is associated with increased mortality, and smoking plays a role in explaining this association. Present findings suggest that DNAm GrimAge is a strong predictor of mortality independent of genetic influences among female twin pairs.

An invitation to participate in the study was sent to 414 female twin pairs, aged 63–76 years. Of 199 twin pairs, at least one twin died in 112 pairs during follow-up:

This epigenetic age estimate that measures biological age and runs alongside, but not always in parallel with chronological age, may inform life expectancy predictions. Further research is needed to determine whether results apply to men, and the extent to which DNA methylation age can be used as a clinical biomarker of lifespan.”

https://clinicalepigeneticsjournal.biomedcentral.com/articles/10.1186/s13148-021-01112-7 “Does the epigenetic clock GrimAge predict mortality independent of genetic influences: an 18 year follow-up study in older female twin pairs”

If you don’t have a twin, substitute yourself as an analogous entity who has opposite behaviors. Don’t assume that smoking cannabis will produce different results from tobacco.

Meanwhile, Dr. Steven Horvath, who has a twin, continued his 2021 torrent of coauthored studies last week with Epigenetic clock and methylation studies in elephants. Amazing epigenetic clock information being published this year. Dr. Horvath is completely open to evidence, IAW, a real scientist.