Intended for healthcare professionals


Masks, humidity . . . and other stories

BMJ 2021; 372 doi: (Published 04 March 2021) Cite this as: BMJ 2021;372:n540


If your spectacles steam up when you wear a mask, console yourself with the thought that this humidifying effect may be one reason why masks help reduce transmission and severity of respiratory infections. Tests of common types of masks showed that they all increased the humidity of inhaled air, especially at low ambient temperatures. High levels of humidity promote mucociliary clearance of pathogens from the upper respiratory tract and enhance the effectiveness of the innate immune system (Biophysical J doi:10.1016/j.bpj.2021.02.002).

Physical activity is good for the brain

It’s well established that leisure time physical activity is good for health generally and vascular health in particular. …

View Full Text

Log in

Log in through your institution


* For online subscription