It’s the middle of summer, and we’ve just had a massive heatwave across most of Europe, so I figured it’s about time to talk about that great big ball of fire that is the source of all life, and the kryptonite to dermatologists everywhere.
There is a lot of misinformation and scaremongering about the sun. On one hand, many “experts” tell people to wear sunscreen all the time, even in the winter and supplement with vitamin D instead of getting it from the sun. It’s all to prevent skin cancer and aging! But the truth is far more nuanced than this. In fact, I (and many other experts) would go so far as to say this is dangerous advice. I’ll start with the caveat that yes, too much sun exposure is harmful. If your skin burns, you will cause damage and sharply increase the risk of skin cancer. Excessive skin exposure can also accelerate aging of the skin. However this does NOT mean the sun is dangerous and to be avoided at all costs. We NEED sun exposure to be healthy. The best advice is to get some sunshine a few days a week (the amount you need depends how dark your skin is), and use (non-toxic) sunscreen after this to prevent burning. I have recently started to use sunscreen on my face at all times, just to prevent any skin aging. As long as most of my body gets some sun exposure, it’s all good.
Below are some of the reasons to ensure you get enough sunshine:
- Sunshine gives you FAR more than vitamin D.
It’s a common misconception that the only reason we need sun exposure is for the vitamin D. It’s led to a grave misconception that one can simply replace sunshine with a pill. But actually a large scale placebo controlled trial of 25,871 participants suggested vitamin D supplements don’t do much. And yet there is plenty of evidence that those with low vitamin D levels are at higher risk of all sorts of diseases including cancer, heart disease, depression, osteoporosis and autoimmune disease. What gives? Maybe it’s the sunshine (the correlate of vitamin D), rather than vitamn D itself! In fact sunshine helps your body produce these incredible compounds:
– β-Endorphin: UV exposure increases blood levels of endorphins which reduce pain, and may explain why basking in the sun feels so good.
– Calcitonin Gene-Related Peptide: This causes vasodilation ,and protects against high blood pressure
– Substance P: This is another neuropeptide released by sensory nerves in the skin in response to UV radiation. This peptide modulates the immune system, is involved in wound healing and improves blood flow.
– Melanocyte-Stimulating Hormone: This hormone is involved with skin tanning in response to skin exposure but also has roles in a polypeptide hormone that reduces appetite, increases libido, and is anti-inflammatory.
– Adrenocorticotropic Hormone: This hormone is created from the same precursor (pro-opiomelanocortin) as Melanocyte-stimulating hormone. It controls cortisol release as well as the release of other adrenal hormones.
– Nitric oxide – a potent vasodilator, which reduces blood pressure.
- Skin cancer might not be so bad.Okay hear me out.. yes this might be one of the more controversial things I’ve said on this blog. First of all there are different types of skin cancer. Basal cell and Squamous cell carcinomas are the most common and the least deadly. In fact people diagnosed with basal cell carcinoma are more likely to live longer than healthy controls, even after controlling for age, co-morbidity and socio-economic status. If there was one cancer you might be considered lucky to get, it’s Basal cell carcinoma! Probably because the cancer itself is so benign, but is associated with lots of sun exposure which protects against all-cause mortality. Melanoma is the type that is more likely to kill people, but only accounts for about 1-3% of all new skin cancers. (There are other rare types of skin cancer but I won’t get into them here). On the topic of melanoma, this study – tracked 29,518 Swedish women in a prospective 20 year followup on Melanoma. They asked questions about sun exposure and other lifestyle factors and followed them up. Those who had the most sun exposure had HALF the mortality rate of those with the least exposure! And yes, the sun worshippers had higher rates of melanoma…but they were EIGHT times less likely to die from it! In fact, the authors of the study actually quote “Nonsmokers who avoided sun exposure had a life expectancy similar to smokers in the highest sun exposure group, indicating that avoidance of sun exposure is a risk factor for death of a similar magnitude as smoking.”Far more people die from the diseases that sun exposure helps prevent like cardiovascular disease and non-skin cancers. I know which odds I’d rather have.
- The nuance of sun exposure matters.
The people most likely to get deadly skin cancers are those who exposure themselves briefly to intense sun exposure, especially if they burn, and especially if this happens in childhood/adolescence. Frequent mild exposure is far safer. Furthermore, your skin type matters. Fair skinned redheads with >50 moles need to be much more careful with sun exposure as they are far likelier to burn, whereas dark skinned people need to ensure they get adequate levels of sunshine similar to the amounts their ancestors got in their countries of origin. This app might help you work out good sun exposure times.
- Most sunscreen is toxic
Your skin absorbs what you put on it, and unfortunately many of the chemicals in sunscreen that enter your body via your skin have NOT been tested for safety. Furthermore many sunscreens contain oxybenzone and other chemicals that literally destroy coral reefs, which has prompted some places like Hawaii to ban them. Look for safe sunscreens on the EWG Skin Deep database.
In summary, know your facts and make educated decisions about how much sun to expose your skin to. Be sensible, and don’t buy into the hype that sun exposure is inherently bad.