Are two face masks better than one?

We all know we need to wear a mask. But should we be wearing two?

Once the dust had settled in Washington, the fashion takeaway from last week’s inauguration was not Michelle Obama’s hair-flick or Amanda Gorman’s red Prada hairband. It was “double-masking”.

Peeking out from underneath Joe Biden’s black face covering? A medical-grade mask. Underneath Gorman’s red and diamante-strewn one? Another mask.

The practice, which usually involves wearing a medical-grade mask under a more aesthetically pleasing cloth mask, was this week backed by Dr Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, who told NBC News Today that it could lower the risk of spreading the virus. “If you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective,” he said.

David Heymann, a professor of infectious disease epidemiology at London School of Hygiene & Tropical Medicine, struck a more cautious note when talking to the Guardian, saying double-masking was a valid “precautionary measure” but people needed to be reminded that masks stopped the spread of infection rather than protecting the wearer from getting the virus.

“I understand that it might give the wearer a sense of control. But people need to be reminded that the reason they are wearing the mask, or masks, is to protect others. I am sure people find it reassuring but the eyes are still exposed,” he told the Guardian. By contrast, he added, there was some growing evidence that people who wore glasses had less risk of infection.

According to Heymann, there is not a large body of evidence to prove that cloth masks are an effective method of protection. “If you are wearing a mask with an inside lining and an outside lining, so two different materials, it may be the same as a double mask of a single thickness made from two different materials.” Much depends on the fabric, and for this reason it would be very hard to make double-masking mandatory.

“The best way to protect yourself still remains physically distancing [yourself from others], and washing your hands,” Heymann says. However, a lot of the good press surrounding double-masking remains psychological. “If you want to wear two masks nobody would say that’s wrong, and I understand that’s the case if it’s a fashion statement.”

The conflation of fashion with PPE – medical grade masks with floral and silk masks by Marni and Fendi – has been a source of ire since masks were introduced last spring. As with all accessories, masks ran the risk of becoming statements of not just health, but identity.

In the US, where mask-wearing last year became one of many battlegrounds in a culture war, double-masking seems to double down, as it were, on masks as a symbol of identity politics. In a society in which wearing a mask can be seen as positioning yourself in the progressive camp, wearing two could be read as a political statement, rather than a fashion one. But then, wearing two masks would seem to be very much about incorporating fashion into protective wear.

If nothing else, double-masking may at least keep a wearer comfortably covered for longer. A tighter fit can improve the effectiveness of the mask, said Heymann, and prevents glasses from fogging up as well as slipping. If only someone had told Bill Clinton. For much of the inauguration ceremony, the former president wore his mask below his nose.