Earlier quoted context omitted.
UK expert disagrees —- marijuana does less damage to the user, and much less to friends and family, than alcohol does: https://www.bbc.com/news/uk-11660210
That article is about the harm to society as a whole. Pulling a single line from the article to summarize: > Prof Nutt told the BBC: "Overall, alcohol is the most harmful drug because it's so widely used.
Another way to measure is the therapuetic index. It's the ratio of the lethal dose divided by the effective dose. It's about 10 for ethanol and 30,000 for cannabis. Larger is safer.
This means drinking ~10 times as much as your usual amount of alcohol has a 50% chance of killing you. For cannabis you would need to consume ~30,000 times as much (which is probably not even physically possible).