is smoking one cigarette a day dangerous just could increase risk of heart disease by 50% | The Independent what if you smoke 1

There are other reasons as well

[Why a sociological user perspective in tobacco research?]

No one is more attractive with a 150mm briar-wood appendage sticking out of their mouths apart possibly from Sherlock Holmes, Tony Benn or Gunther Grass, and I dont want to look like I think Im any of them

The effects are highly variable but may include: Hallucinations Delusions Aggression Confusion Suicidal behavior Seizures Respiratory issues Increased risk-taking behavior Heroin Though there have been a few reports of heroin-laced marijuana, its more likely for someone to deliberately combine heroin and marijuana than to be deliberately contaminated