Cancer-causing or cancer-protective? What they don’t tell you about sunlight exposure
(NaturalHealth365) Common knowledge tells us that heavy sunlight is harmful to human health and causes worrisome issues like wrinkles, sunspots, and skin cancer (with estimates showing that more than 5.4 million cases of basal and squamous cell skin carcinomas are diagnosed each year in the United States, affecting roughly 3.3 million people). Accordingly, in theory, we must avoid too much sun exposure (especially at midday), and we should cover ourselves in layers and sunscreen – never mind that many conventional sunscreens contain cancer-causing chemicals!
But, what if we learned that sunlight has been shown to have a protective effect against cancer? What if there are benefits of sunlight that we might be missing out on because we’ve been too worried about getting too much?
Shedding a new light on the sun? INCREASING sunlight exposure may actually reduce risk of certain types of cancer by up to 50%
While it’s true that avoiding excess sun exposure may help us avoid skin cancer, it turns out that not getting enough has negative repercussions and may actually increase our risk of other types of cancer, including breast, colorectal, and prostate cancers.
How is this so? As current research suggests, allowing our skin to be exposed to sunlight is the best way for our body to produce vitamin D. This vitamin acts as a crucial hormone in the body and is involved in hundreds of key physiological processes that we need to survive and thrive – including immune function. It follows that low levels of vitamin D have been consistently associated with issues ranging from metabolic syndrome to cardiovascular disease to mood disorders … and the link between vitamin D and cancer has long been known, too.
According to a narrative review paper published last year in the peer-reviewed journal Nutrients, research from the late 1930s involving U.S. Navy found that sailors with high sun exposure had 8 times the typical rate of skin cancer but only 40% of the expected rate of internal cancers. And in the 1970s, American researchers picked up on an important geographic trend – rates of colon cancer were higher in northeastern states where there’s less sun in the winter (and what winter sun is available isn’t able to help us produce as much vitamin D because of its angle in the sky).
As subject matter expert Michael Holick wrote in his 2008 paper in the Clinical Journal of the American Society of Nephrology, data suggest that “there is a 30 to 50% reduction in risk for developing colorectal, breast, and prostate cancer by either increasing vitamin D intake to least 1,000 IU [per day] of vitamin D or increasing sun exposure to raise blood levels of [Vitamin D] >30 ng/ml.” The leading theory is that vitamin D helps key cancer-protective processes in the body, including the inhibition of tumor cell growth and spread.
By the way, ever wondered what is considered vitamin D deficiency? While many in the scientific community consider blood levels of less than 12 ng/mL as deficient, other experts put the number higher, anywhere from 20 to 29 ng/mL. If you’re curious, consider requesting a comprehensive blood test from a trusted healthcare provider, such as a functional medicine doctor or simply purchase a vitamin D test kit, yourself.
Cancer controversy or not, here are some other well-known benefits of sun exposure
The main takeaway here is that we don’t need to be afraid of the sun – just be savvy with the sun! Here are some known benefits of moderate sunlight exposure:
- Improved sleep – in fact, going outside to see the early morning sun can help normalize your body’s circadian rhythm (your “internal clock”) … meaning that if you want to fall asleep easier at night, you need to actually start with habit changes in the morning!
- Improved mood
- Improved bone health (likely by way of vitamin D production)
- The potential for additional protective benefits (also by way of vitamin D production) against other common chronic diseases, including hypertension, type I diabetes, rheumatoid arthritis, asthma, and multiple sclerosis (like certain cancers, many of these conditions are also found in higher incidences among populations living in more northern geographical latitudes)
So, how much is the “right” amount of sun exposure?
Keep in mind this depends on several factors, such as where you are located geographically and the color of your skin, given that these factors can affect how much vitamin D your body will be able to make in response to sunlight. But a general recommendation is about 10 to 20 minutes in the midday sun during spring and summer (or 25 to 40 minutes for people with darker skin) and upwards of two hours during the winter in northern climates (hence the importance of vitamin D supplementation for many people).
Let as much of your skin enjoy the sunlight: back, trunk, arms, and legs. And when it is time to put sunscreen on, be sure to choose one you trust that doesn’t contain harmful chemicals or simply cover your body with comfortable clothing.
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