It’s an idea that has been with us for many decades, with much debate on the topic, and a great deal more contradictory advice. But what is the truth behind the claim that sun expose can help clear up acne?
It is a commonly held belief that getting out into the sun and giving your skin a ‘healthy tan’ (a misnomer in itself) can reduce the appearance of acne and even help to heal skin. But where does this idea come from? Surely there is no smoke without fire, so there must be some truth behind it, right? Let’s take a closer look at some of the reasons why this belief has entrenched itself into public opinion.
Acne can sometimes be attributed to a lack of vitamin D and as any vitamin buff will know, this is produced by the body when the skin is exposed to sunlight. It is true that extreme avoidance of UV exposure can cause skin blemishes (we’ve all seen those computer game teens who venture out of their rooms only for bodily essentials), but it is very rare for most people to suffer from a vitamin D deficiency severe enough to cause acne.
One cause of acne that has been proven time and time again is stress. High levels of anxiety or stress can cause hormone imbalances, which often leads to an overproduction of sebum from the sebaceous glands. Too much sebum can not only cause pores to become blocked, but it can also encourage the bacteria build up on the skin, both of which can lead to acne. Stress also tends to cause secondary problems that can lead to skin blemishes, such as altered diet, disrupted sleep patterns and habitual activities like rubbing your face or biting your lips.
So how does this relate to sun exposure? Well, people are often exposed to sun when they have time away from everyday stresses, like going to the beach on the weekend or on vacation somewhere hot. Bearing this in mind, when people automatically attribute their improved skin to the sunshine, it could very easily be the case that they are simply less stressed.
Much like the previous point, when you are exposing the skin to the sun, you are by default exposing it to fresh air. Studies have shown that the open air provides a better environment (excluding extreme hot or cold climates) for healthy skin. So this is yet another variable to consider.
UV rays from the sun stimulate capillary dilation on the skins surface, which is what causes the pink/reddish look directly after exposure. UV rays also cause the body to produce melatonin, which darkens the color of the skin, largely as a protective reaction to further exposure. Both of these acts cause the skin to blend in with acne, which is often darker in
color than healthy skin, thus hiding the blemishes. So whilst you’re thinking your acne is improving, it might in fact just be disguised by a darker overall skin tone.
Certain shortwave UV rays (<280nm) are known to kill bacteria and are used as germicides to sterilize surgical tools, restaurant utensils and even smelly shoes. As bacteria on this skin is a known cause of acne, exposing it to shortwave UV rays from the sun should help fight it off and reduce skin blemishing right? Well, not quite. Unfortunately the earth’s atmosphere filters out these shortwave rays, so we don’t get any bacteria-fighting benefits. Having said that, shortwave rays would do untold damage to our skin if they weren’t filtered out, so perhaps we shouldn’t curse the atmosphere just yet.
If you look at all the recommendations from leading health bodies and independent organizations, the vast majority will suggest that you don’t purposefully expose the skin the sunlight in order to cure acne. This is largely because there is no empirical evidence that UV exposure helps acne, but also because UV light exposure often causes more harm than good. Both UVA and UVB rays (long and medium length) are harmful to the skin and cause cellular damage and dryness. These can in fact lead to worsening acne as the skin produces more sebum to counteract the dryness. Further to this, a number of acne medications including retinoic acid and antibiotics cause photosensitivity of the skin and can make it more susceptible to UV damage.
What health bodies do advise however is that you enjoy the sun wiliest protecting the skin with a suitable sun cream applied. Cancer Research UK suggests no less than factor 15. This way you get the benefits of fresh air and lower stress which promote healthy skin, whilst still protecting it from harmful UV rays.