Doctors Urge Daily Indoor Sunscreen Use as Car Windows Can Raise UVA Exposure 5 to 6 Times
Updated
Updated · The Washington Post · Jul 27
Doctors Urge Daily Indoor Sunscreen Use as Car Windows Can Raise UVA Exposure 5 to 6 Times
1 articles · Updated · The Washington Post · Jul 27
Summary
UVA and visible light can still reach skin indoors, prompting dermatologists to recommend daily sunscreen even for people who spend most of the day inside.
2011 and earlier studies tied that advice to measurable exposure: more than 82,000 U.S. melanoma cases skewed slightly to the left side, while car-window tests found drivers’ left arms got 5 to 6 times more UV.
Visible light adds another concern for darker skin tones, melasma and hyperpigmentation; a 2010 study found it caused darker, longer-lasting pigmentation than UVA in darker-skinned volunteers.
Dermatologists said shoppers should prioritize broad-spectrum sunscreen for UVA coverage, consider iron oxide for visible-light protection, and not overrate higher SPF—SPF 30 blocks about 97% of UVB versus 98% for SPF 50.
Experts said sunlight remains the main skin-damage source—far above phones or computer screens—so indoor use is a supplement, not a substitute for stronger protection outdoors.