Many of us think that only direct exposure to sun is dangerous for our skin – we assume that “natural light” is fine.
Think again! UVA, which causes brown spots, uneven pigment, wrinkles, and skin cancers, is present in all natural light. It goes through clouds, through the windows in your home and office, and through your car glass. So, it’s present around you pretty much all day.
And just a little bit of UVA, all day, every day, really adds up.
To keep your skin beautiful and healthy, avoid UVA as much as possible, especially if your skin tone is lighter. The lighter your skin tone, the less natural protection you have against sun damage. UVA is sneaky – it tends to NOT cause sunburns, and instead, just damages skin slowly.
Most sunscreens now block UVB well (the SPF number is referring to UVB protection). But sunscreens do NOT tell you how much UVA they block. Your sunscreen may be labeled “broad spectrum,” but essentially that means nothing.
Only zinc (in higher concentrations) effectively blocks UVB and UVA well. The concentration you need depends on how much you are outdoors and in your car and what you do outside. For example, a good concentration for just a little outdoor exposure – like a run in the early morning – in the spring/summer might be 5-10% zinc.
If you are cycling outdoors for hours and sweating, or if you’re working outdoors, aim for a concentration of more like 10-20% zinc – and be sure to reapply when needed.
And keep in mind, UVA is the strongest two months on either side of summer solstice day. So, those in the US (and elsewhere in the northern hemisphere) need to be especially vigilant in May, June, July and August (those in the southern hemisphere need to mind the months around December solstice).