With summer weather approaching, most people can expect to be spending more time outdoors. In this Q&A, Arianne Shadi Kourosh, MD, MPH, director of Community Health in the Department of Dermatology at Massachusetts General Hospital, shares some considerations for dermatologic care and protection from the sun during COVID-19.

Q: Most Americans have been spending an unprecedented amount of time indoors during quarantine. Could this extended period of time with reduced exposure to sunlight make some people’s skin more susceptible to sun damage?

Kourosh: It’s important to highlight that sunlight is not the only source of radiation that our skin faces every day. Visible light and infrared radiation (heat) can also cause damage and aging, and hyperpigmentation of the skin.

For example, the light emitted from computer screens and mobile devices, including blue light within visible light spectrum, can affect the skin and eyes, contributing to skin damage, eyestrain and possibly even cataracts. During the COVID-19 pandemic we are spending more time facing screens than ever, so it’s good to be mindful of this and take protective measures. 

Q: Should people apply sunscreen more frequently if they’ve been spending less time in the sun?

Kourosh: With more time spent indoors and all the mask wearing during the pandemic, people have been experiencing more sensitive skin, breakouts and clogged pores. So it may be more helpful to substitute our regular high SPF sunscreens for a lighter moisturizer with some SPF in the mornings.  A little SPF in our moisturizer is still important because of all the additional time we are spending in front of computers and mobile devices to protect against the higher energy visible light coming off the screen.

Q: If you’re wearing a mask do you still need to apply sunscreen to your whole face?

Kourosh: Yes, as harmful rays from sunlight can penetrate through clothing. Unless your mask is made of sun protective (UPF) fabric, it’s a good idea to apply at least a light moisturizer with sunscreen. There are also sun protective treatments that one can use to wash clothing and fabrics to make them more protective.  However, it’s still a good idea to use a moisturizer in the morning that has some sunscreen, especially if one is exercising outdoors or spending a lot of time facing computer or mobile device screens.

Q: What are the risks of spending too much time in the sun without protection? Can the immune system be impacted by sun damage to the skin?

Kourosh: Sun damaged skin is weaker and a less protective barrier. We need our skin to be a strong protective barrier to keep in moisture and hydration and protect us from harmful substances penetrating into the skin. Those who have gotten too much sun exposure over a lifetime have thinner, weaker skin that is more prone to injury and damage.

A little cautious sun exposure, for example fifteen to twenty minutes daily to areas of skin affected by eczema, psoriasis and vitiligo can actually be helpful for people who struggle with those conditions as it can calm the over-reactivity of the immune system that contributes to skin lesions in these diseases.  A little sunlight can also help those with vitiligo get their skin pigment back in areas that have lost pigment. However, as with everything, this is very much about moderation, where a small dose can be helpful, while too much sun exposure and risk of sunburn can actually worsen these conditions.

Q: Some news outlets have reported that direct sunlight can kill or inactivate the coronavirus on surfaces, including the skin. What advice would you give to people who have heard these reports?

Kourosh: Yes, the concept that sunlight, specifically ultraviolet (UV) rays, can kill microbes has actually been known for nearly a century. The difficulty is that the dose and wavelength of light have to be exactly right and scientifically tested to kill a certain microbe, whether that’s a bacteria or virus, with a very high reliability.

Knowing that something could theoretically work in principle is different than trying to disinfect an object by leaving it out in the sun or under a UV light source for a while and assuming it has effectively done the job.

Reliable disinfection is critical in an epidemic, and this process has to be measured and proven in a laboratory in order to give us official guidelines for how it can work in every day life.

Q: What are the health risks of getting insufficient sunlight? What advice could you share for anyone concerned that they aren’t getting out of the house enough?

Kourosh: There are real scientific reasons that human beings like to be outside in the sun. One theory is that sun-seeking behavior may have evolved to make sure people spent enough time in the sun to make vitamin D in ancient times when they did not have reliable food sources of vitamin D as we do now.  Some exposure to sunlight can also be important to help with mood and prevent seasonal affective disorder in those who might be more vulnerable, and to help preserve circadian rhythms, our natural sleep-wake cycle.

As Paracelsus, the father of modern toxicology famously taught, “poison is the dose.” As a dermatologist, I see every day how sunlight in small doses can be a medicine, while, if overdone, can be toxic and require treatment to restore a person back to health.

Q: Are there any additional precautions for anyone who has previously contracted COVID-19?

Kourosh: The truth is we are still learning about this virus and what its implications are going to be. Our transition as a society back to life as we knew it or something approaching that is going to require wide spread testing with tests that are accurate and reliable and the development of effective treatments and vaccines. In the meantime we have to be careful and try our best to follow public health guidelines.