When e-cigarettes first appeared around 2010, they were hailed as a breakthrough: nicotine delivery without the toxic tar and combustion byproducts of traditional cigarettes. Public health bodies cautiously endorsed them as a tool for adult smokers to quit, often citing early claims that vaping was 95% less harmful than smoking. More than a decade later, with millions now vaping regularly, the picture is less clear.

A recent study, published in the American Journal of Physiology – Heart and Circulatory Physiology, found that people who vape or smoke have nearly 50% higher odds of elevated blood pressure compared to non-users. This isn’t proof that vaping directly causes high blood pressure – other factors such as diet or exercise could play a role – but it adds to a growing body of evidence that vaping’s early reputation for safety deserves a harder look.

The science behind the concern isn’t complicated. Nicotine in e-cigarette vapour triggers immediate spikes in heart rate and blood pressure. The flavourings and other chemicals can damage the lining of blood vessels – the tissue that prevents clotting and keeps blood flowing smoothly. Research reviews have found elevated rates of heart attack among vapers, particularly among those who also........

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