E-cigarettes are a popular alternative to smoking, but we still know very little about the effects of them on our health. [...] A recent study investigating the effect of e-cigarettes on our oral microbiome found that e-cigarettes have a negative impact on the diversity of the bacteria present. They also cause an immune response from cells, which can lead to long-term damage to the surrounding cells. For this particular study, 123 participants were recruited and split into five groups: smokers, non-smokers, e-cigarette users, former smokers currently using e-cigarettes, and those that use both. [...]