What sun exposure can do is put some skin problems in a dormant state, only to have these trouble spots reactivate at a later date. Sun will dry out the outer skin, which has a temporary effect of drying, as well as a psychological effect of clearing. But as far as being a treatment for problem skin, sun exposure won’t do the trick.
Heat actually activates your oil glands. If you have an oilier skin type, haven’t you found that your skin gets even oilier in the summer months? I see this in my facial room all the time and I’ve heard it from clients for years. And back when I had oily then normal to oily skin it was true for me as well.
When it comes to myths about anything, and in this case skin care, you have to be logical and think things through a bit. Sun exposure can cause all kinds of things to melt. And heating up oil certainly makes it more “runny” if you will. So lying out in the sun to “clear up acne” is probably, in the long run, only going to increase any existing problems.
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