keri russell smoking cigarettes Duty and Honor (2013)

doi:10.1093/aje/kwj160 15

The reasons for delayed wound healing are likely to be multi-factorial: Nicotine causes vasoconstriction and a 30-40% decrease in blood flow soon after inhaling cigarette smoke

If you go through security with one stashed in your carry-on though, you can bet on getting pulled over and having your bag rummaged through to make sure you arent bringing any buds aboard

Yeboah MM, et al

IHME data shows that the United States, Canada, Australia, New Zealand, Japan, South Korea, and countries in Western Europe experienced steep declines over the past two decades that have begun to taper off and plateau

These effects all result from only small amounts of nicotine