E-cigarettes should come with health warnings, according to a Scottish heart expert who is researching the devices. Jacob George, professor of cardiovascular medicine and therapeutics at Dundee university, also criticised public health bodies for what he calls “mixed messaging” over the use of the devices. George is compiling the results of a two-year study, funded by a British Heart Foundation grant, into the effects of swapping cigarettes for vapes on the vascular system and lungs [...]