More than a million people use e cigarettes to stop smoking and there's calls for them to be sold in hospitals but is vaping safe? E Cigs Really Do Help Smokers Quit, a New Study Shows The Motley Fool E cigarettes 'much better for quitting smoking' E cigarettes and cancer: new report faces sharp criticism Vejpkollen.se Vaping may raise cancer and heart disease risk, study suggests Medical research The Guardian