Why should you use sunscreen indoors?
If you are like me, you never would have guessed there are real risks to your skin from UV exposure indoors from everyday light sources we use daily. The question is, does this cumulative exposure to this low dose UV light really cause any significant photo damage? Recent findings suggest that skin protection must be practiced indoors to adequately protect the skin against UV rays and damage.
Lupus and Melasma are two examples of skin conditions that are triggered by UV exposure; what is surprising is that even low-dose exposures to UV light, such as those associated with indoor lighting, may also lead to these conditions. Melasma, a common pigmentation disorder, can be triggered by both heat or UV light. Everyday exposure to ambient indoor light may darken the skin. This is why daily UV protection is so important in both indoors and outdoors.
Most people know that wearing sunscreen outdoors is important in preventing skin cancer and aging of the skin but we have now learned that UV exposure to inside lighting has more significant effects on the skin than we previously realized. It is more important to take precautions to prevent skin cancer and other skin damage from exposure through window glass, and from fluorescent bulbs, halogen lamps, tablet and computer screens.
Studies examining light sources in our indoor environment suggest that indoor lights emit unexpected amount of UV light as measured by a spectral radiometer. This shows that cumulative exposure to indoor lighting may be of clinical significance. Fluorescent lighting has been shown to increase lifetime UV exposure by 3% based on the distance the lamp is from the skin. If the lamp is close – particularly desk lamps, bed lamps, and overhead lamps – the light and heat emitted can worsen skin conditions in photo sensitive individuals. Avoiding close contact with the light or wearing SPF indoors can help reduce this exposure.
In addition to the use of indoor lighting, the light that passes through glass is easy to underestimate. Unlike UVB rays, UVA rays pass through glass and affect the skin. The percentage of UVA rays that pass-through glass depends on the type of glass and the coating on the glass. Unfortunately the glass in most residential and commercial buildings do not have UVA protection. The use of SPF while indoors in addition to blinds, shades, and tinted glass, and increasing the distance from windows and doors are the best methods of protection from cumulative daily UVA exposures.
Another surprising source of UV exposure is the car! The side and rear windows in cars provide no protection from UVA rays. It is really important to wear SPF daily whether in the home, office or car. Daily cumulative exposure can cause chronic skin damage and early signs of photoaging.
Other sources of indoor exposures include TV monitors, computers, tablets, and phones. Although we are not necessarily getting UV radiation form these devices they do emit blue light. The amount of time spent in front of these screens and their proximity can pose a problem as blue light can increase free radicals, which is the most common contributor to premature aging. These devices also emit heat, which can exacerbate rashes and other heat-sensitive skin conditions.
Blue light has a very short wavelength with high energy. Close-range blue light has been associated with increased skin hyperpigmentation; to prevent the worsening of such conditions, it is important to be aware of the amount of time these devices are in close to the skin.
Wearing SPF indoors can reduce the risk to commonly overlooked exposure to UV and blue light. Skin protection with broad-spectrum sunscreen both inside and outside should be used daily for maximum protection. Care should also be taken to limit exposure times and increase distance of these objects from the skin and eyes.
