Sun exposure and your health has been clouded by confusion. We’ve been told conflicting information with one side of the coin touting that the sun causes cancer while on the other side of the coin, we’ve been told that the sun is the only way we can get Vitamin D. It’s like a love hate relationship - we love it, yet many of us fear it at the same time. We’re going to explore this relationship and afterwards you may notice your relationship with this floating ball of fire is completely different.
More and more research shows just how important it is for overall health to get enough sun exposure. According to the study The risks and benefits of sun exposure 2016, “Studies have shown a wide range of health benefit from sun/UV exposure. These benefits include natural defenses against various types of cancers, cardiovascular disease, Alzheimer’s disease, dementia, myopia and macular degeneration, diabetes, and multiple sclerosis.” In fact, In the early 1900s, nurses would roll beds outside so patients could get a healthy dose of sunlight. Why did we stop? Does the sun truly cause skin cancer?
One reason sun exposure is so important is because the sun provides us with vitamin D. Vitamin D benefits the body in so many ways. Research indicates that Vitamin D, the so-called “sunshine vitamin” impacts not only your bones and skeletal structure, but also immune function, blood pressure, mood, brain function and your body’s overall ability to protect against a range of illnesses.
Vitamin D (also called 25-hydroxyvitamin D) is a fat-soluble vitamin and steroid hormone that is present only in small amounts in certain foods, and it’s made in our bodies only when our skin is exposed to the sun. It’s considered an “essential” nutrient because the human body cannot make it on its own, without the assistance of food and sunlight.
Humans evolved to spend time outdoors in the sun. The body converts sunshine into chemicals that are then used by the body. In particular, when UV-B sunshine rays land on the skin, a substance in the skin called 7-dehydrocholesterol is literally converted into vitamin D3 (the more active form). Vitamin D has Immunomodulatory effects and cancer, as well as autoimmune diseases, are an immune dysregulation diseases. We quite literally rely on the sun for survival!
Ideal levels of vitamin D are between 40 and 60 nanograms per mL. Here’s an important note from the “Risks and benefits of sun exposure 2016” study: “It is apparent that vitamin D supplementation”—or supplements—“are not an effective substitute for adequate sun exposure.” While Vitamin D supplementation has some benefits, it is not a substitute for sun exposure.
Now that we know the sun is critical for our overall wellbeing, what about the risks? Melanoma is the most dangerous form of skin cancer and much information we’re told states it’s caused by the sun. However, nonburning sun exposure reduces the risk, while burning increases risk. According to the “Risks and Benefits of Sun Exposure 2016“ it has long been observed that outdoor workers have a lower incidence of melanoma than indoor workers. A 1997 metanalysis found odds ratio of 0.86. Odds ratio is an assignment of risk. If you’re above 1.0, depending on how the study is set up, you have an increased risk. If you’re below 1.0, you have a decreased risk. In another study, the authors concluded “We found that almost all epidemiological studies suggest that chronic, not intermittent, sun exposure is associated with reduced risk of certain kinds of cancer.” High-level science is showing that the most dangerous form of skin cancer, melanoma, is protected against by chronic, non-burning sun exposure.
The key word here is chronic. This means that you’re not just getting five minutes in the sun or only exposing yourself to an intense amount of sun on vacation. It means you’re getting 20, 30, 40, 50 minutes in the sun on most days of the week. The amount of sun you need is dependent on the time of year and your skin type.
The Fitzpatrick scale, shown below, classifies six skin types based on the response of different skin types to UV radiation. Type 2 skin types burn quite easily while the darker your skin, the less prone you are to burn and the longer you need in the sun. So how much sun exposure should we be getting? Between 15-30 minutes of sun exposure two three times per week, with the duration depending on your skin type. One thing that’s recommended in the research is what’s called the minimal erythemal dose, which means get enough sun to cause a slight pigment change in your skin, a slight pinkening of the skin or a slight tanning of the skin, and that should be sufficient. You certainly never want to burn.
Once your personal threshold in the sun has been reached, sun protection should be used; this may take the form of going indoors, seeking shade, covering up, or applying a natural sunscreen. However, sunscreen’s ability to prevent skin cancer has been recently called into question by a 2018 study that, after reviewing the existing data, found no evidence of a decreased risk of skin cancer with sunscreen use. Additionally, many of them contain carcinogenic ingredients that promote cancer.
So what’s the takeaway? Don’t be a vampire and hide away from the sun! Hiding behind clothes, sunscreen and the like at every sun exposure can actually be damaging to your health. Instead, expose yourself to the sun in a reasonable and responsible manner on most days to get the immune protective and DNA repair your body needs for optimal health!
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This blog post is for informational and educational purposes. It’s not meant to treat any health condition or to be prescriptive for anyone.
Always be sure to work with your healthcare practitioner before implementing new recommendations and/or supplements.
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