An anonymous reader quotes a report from The Verge: Even after puffing on just one electronic cigarette with nicotine, healthy non-smokers were found to have a biological marker known to increase the risk of heart disease in tobacco users, according to a new study. The research, published in Journal of the American Heart Association, shows that nicotine is not harmless, as many people believe. It can affect a smoker's health in more than one way, and not just by triggering addiction. Another study, conducted by Middlekauff that was published earlier this year, showed that people who use e-cigs almost every day have biological markers known to increase the risk of heart disease in tobacco users. These included an increase in adrenaline levels in the heart, which can predispose smokers to bad heart rhythms, heart attacks, and sudden death, as well as increased oxidative stress, an imbalance in the body's ability to defend itself against the damaging action of free radicals. Oxidative stress can lead to changes in blood fats and lead to arteriosclerosis. That study, however, didn't show what exactly was causing those changes. E-cigarettes can have different flavoring and solvents, as well as nicotine. So to identify the culprit, Middlekauff brought 33 healthy non-smokers and non-vapers into the lab. On three different days, one month apart, the participants were asked to puff on three different kinds of e-cigarettes for 30 minutes: one with nicotine, one without nicotine, and a sham e-cig that was empty. The researchers did blood tests and measured the subjects' heart rhythms, and found that the participants had high levels of adrenaline in their hearts after they smoked the e-cig with nicotine, but not after they puffed on the e-cigarette without nicotine or the empty e-cig.
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