The British Heart Foundation is funding a new study comparing the effects of electronic cigarettes (e-cigs) and tobacco cigarettes on smokers’ heart health.

Run by Dundee University, the two-year study will test the effects of both types of cigarette on volunteers’ blood vessel function.

Participants will be split into three groups, with one continuing to smoke tobacco cigarettes. The others will switch to e-cigs containing nicotine plus flavour, or switching to e-cigs containing flavour alone.

Dr Jacob George, from the university’s school of medicine, said: “E-cigs are sold on the principle that they are a much safer alternative to traditional cigarettes because they don’t contain harmful substances like tobacco and tar.

“However, many e-cigs contain nicotine, which may be harmful to blood vessels. We want to see whether the e-cigs are better for blood vessel function compared to traditional cigarettes.

“Many people seem to think that this is the case but as yet there is no hard scientific evidence to prove this.”

News of the study comes as new research from Greece indicates that e-cigs could be as bad for the heart as smoking tobacco.

A team of scientists monitored a small group of participants’ hearts while smoking conventional cigarettes and e-cigs.

In the short term they found that the two activities led to similar levels of stiffness in the main artery. Both also raised blood pressure.

The Greek scientists stressed that this only revealed short-term damage and that more research was needed into long-term effects.

New EU rules governing the manufacture of e-cigs are set to come into force on 20 November. The new rules include a ban on the manufacture of all e-liquids with a nicotine content of more than 20/mg/ml.