Nature has given us potent therapies that are scientifically proven to decrease the risk of disease. They don’t require a prescription, are completely free and dramatically move the body toward health. Unfortunately, they are so easily accessible that many find it difficult to implement adequate dosages. One of these therapies is water and the other is sunshine.
We discussed the importance of daily sun exposure in a previous article outlining our seven basic lifestyle guidelines. This article will dive deeper into the subject, outlining the many risks of underexposure based upon scientific literature.
“Insufficient sun exposure has become a major public health problem, demanding an immediate change in the current sun avoidance public health advice. The degree of change needed is small but critically important” -Hotel at al. 2016 (1)
Vitamin D is known as the sunshine vitamin because it needs adequate sun exposure to be synthesized into Vitamin D3. Because of this, levels have dropped dramatically over the last 20 years as people began limiting their exposure to sunlight. In 2009 the Archives of Internal Medicine revealed that 70% of caucasian people, 90% of hispanic people, and 97% of black people in the United States have insufficient levels of Vitamin D (2). Even more unfortunate, the standard recommended ranges in the United States (20mg/dl) provide minimal benefit, and only protection for a nutritional deficiency, not an adequate recommendation for achieving optimal health.
Scientific evidence indicates that the synthesis of vitamin D from sun exposure works in a feedback loop that prevents toxicity and dramatically decreases the risks of many illnesses ranging from cancer to cardiovascular disease. Due to the uncertainty about cancer risk from sunlight, the Institute of Medicine has not issued recommendations for the amount of sun exposure required to meet vitamin D requirements.
“Drug companies have learned that they can sell billions of dollars of fear relief in the form of sunscreen products but are unable to sell the sun.” -Michael F. Hollick
Below we will look into the major health benefits of adequate, unprotected sun exposure, but the gains are not limited to vitamin D production alone. Sunglasses block the light's ability to enter the eyes which is an important component to regulate blood pressure, body temperature, respiration, digestion, sexual function, mood, immune and hormonal modulation, and circadian rhythm. (3) As light enters the eyes, photoreceptors convert the light into nerve impulses that travel along the optic nerve to the brain, resulting in regulating crucial autonomic functions. Along with adequate daily sun exposure, it is recommended that sunglasses be limited to receive all of the benefits that natural sunshine has to offer.
As expressed above, sun exposure has many benefits independent of Vitamin D levels alone, which is why it’s imperative to focus on both supplementation and adequate daily sun exposure. At the end of this article, we will discuss what the right amount of sun exposure is for you. Naturally, the correct amount of sun exposure, as well as how to adequately supplement with Vitamin D, will vary from person to person. Both are crucial for optimal health and longevity.
Reduced Risk of Melanoma
Skin cancer is a prominent reason for sun avoidance and the over-application of sunscreen. But, even with the sun avoidance health scare, the incidence of melanoma in the United States has increased from 1 per 100,000 people per year to 23 per 100,000 per year in 2012 (1). A meta-analysis conducted in 2016 concluded that non-burning sun exposure is actually associated with a reduced risk of melanoma, whereas sunburns are associated with doubling the risk of melanoma (4). The meta-analysis also goes into great detail on how vitamin D produced in the skin through adequate non-burning sun exposure can enhance DNA repair, thus lowering cancer risk. There has been no consistent evidence that the use of chemical sunscreens reduces the risk of melanoma (5). Sunscreens do, however, reduce acclimatization to UVR and vitamin D production in the skin.
“Since public health authorities recommend liberal use of sunscreens for good health, the labeling of sunscreens should contain a statement about the possibility of vitamin D deficiency that may result from excessive use of sunscreens and that sunscreens have not been shown to be effective in reducing the risk of melanoma.” -Hoel et al 2016
Reduced Risk of Cardiovascular Disease
Along with conscious breathing, there are many scientific findings correlating UVR-induced nitric oxide with a reduction in hypertension (6). These particular studies demonstrate that the stores of nitrogen oxide in the human skin are mobilized by exposure to UVA radiation (sunlight), resulting in arterial vasodilation and a decrease in blood pressure independent of vitamin D (7). Another study concluded that Vitamin D supplementation has a beneficial effect on reducing serum cholesterol, LDL cholesterol and triglyceride but not HDL cholesterol levels, suggesting that vitamin D supplementation may be useful for people with a high risk of cardiovascular disease (11).
Reduced Risk of Obesity
Similar to the benefits of UVR exposure for reducing the risk of cardiovascular disease, Geldenhuys et al. 2014 suggest that UVR exposure may be an effective means of suppressing obesity and metabolic syndrome (9). Again, this is another scenario where the benefits are independent of vitamin D levels and dependent on sunlight making direct contact on unprotected skin. If fat loss is an important goal for you, daily adequate sun exposure should be as well. With these findings, it is no surprise why sunshine is one of our seven basic lifestyle recommendations.
Reduced Risk of Cognitive Decline
A study was conducted on a group of 1,658 Americans age 65 and older who were free of dementia and able to walk unassisted. These participants were followed for six years to investigate who went on to develop Alzheimer's disease and dementia. The findings concluded that those with serum levels below 10ng/mL were twice as likely to develop Alzheimer's disease than those with levels greater than 20ng/mL (12). Although this was one of the first large, prospective, population-based studies, other more recent studies confirm its findings, linking low vitamin D levels with cognitive decline. Care to enhance your cognitive abilities and reduce the risk of decline later in life? It is apparent that Vitamin D supplementation and sun exposure are an important part of your daily routine!
The benefits of both vitamin D levels and adequate non-burning, unprotected sun exposure are endless. This article has only detailed a few, but other findings conclude that Vitamin D and/or adequate sun exposure restricts the development of non-alcoholic fatty liver disease (13), reduces the risk of multiple sclerosis (14) and even cuts breast cancer mortality in half when vitamin D levels are more than 40ng/dL (15). Other studies have shown that more sun exposure in the third gestational trimester was linked to lower risk of type 1 diabetes in male children—and a high prevalence of vitamin D deficiency was found in children with type 1 diabetes (15) and rheumatoid arthritis (16). Other studies have boldly concluded that “the avoidance of sun exposure was a risk factor for all-cause death of the same magnitude as smoking.” This one, in particular, followed 29,518 Sweedish women in a prospective 20-year follow up (18).
If you have made it this far, it should be apparent that immediate action regarding sun avoidance needs to be taken. Because overexposure can be just as dangerous as underexposure it is important to understand what the right dose of sun exposure means for you.
The recommended daily dose given by vitamin D experts ranges from 10-20 minutes of unprotected sunshine each day, ideally between the hours of 10:00 am and 2:00 pm. The darker your skin, the more exposure you will need whereas the lighter your skin, the less exposure you will need. For some, three to five minutes of exposure is all you will need until your skin increases its melanin production.
As for adequate levels of Vitamin D, you can easily see where your levels are by ordering an at-home test from Everlywell. In 2010, the Institute of Medicine defined vitamin D deficiency as anything less than 12ng/dL, but based on numerous amount of research, it has been shown that many of the health benefits start with at least 30 ng/dL. A letter signed by many respected vitamin D scientists and physicians recommends between 40-60 ng/dL which is in line with what the endocrine society recommends as the preferred range for health (17).
Along with daily sun exposure, it is important that supplementation is implemented into your daily practice. Doctor Dickson Thom of The American Center of Biological Medicine recommends a conservative approach to increasing Vitamin D levels through supplements. First, it's necessary to know where vitamin D levels are currently and how much they need to be elevated. If labs report 28 ng/dL and this number needs to be elevated to 50 ng/dL you would subtract 28 from 50 and multiply that number (22) by 100. This protocol would recommend 2200 iu/day. Dr. Thom also states that 100iu/day raises 25-OHD (vitamin d) 1 ng/dL in 3-6 months. There are more aggressive treatments, but it is important to work with a doctor about specific dosages and retest consistently with a goal of 40-60 ng/dL.
"Because vitamin D is so cheap and so clearly reduces all-cause mortality, I can say this with great certainty: Vitamin D represents the single most cost-effective medical intervention in the United States.” -Dr. Greg Plotnikoff
Doctor Hollick, an American Endocrinologist who specializes in the field of vitamin D, suggests a three-step strategy in his book, The Vitamin D Solution, to ensure optimal levels of vitamin D—by combining a sensible amount of sun exposure with supplementation and the consumption of foods rich in vitamin D such as fresh-caught fatty fish, egg yolks, mushrooms and fortified foods.
It is apparent that the full solar spectrum is necessary for optimal health and wellbeing. As humans, we are adapted to produce vitamin D in response to sun exposure and although we can receive this vitamin through food and supplementation we should not ignore the capacity that we possess to produce our own. The benefits of sun exposure clearly go beyond the production of vitamin D and include other physiological responses including the release of nitric oxide, production of beta-endorphins and the regulation of circadian rhythms, all essential components of a healthy life. It is now proven that moderate sun exposure, less than the time required to burn—to the arms, shoulders, trunk, and legs—should be sought rather than avoided (19).
The benefits included in this article are only part of the story on how adequate sun exposure is necessary for optimizing health, regulating autonomic processes, decreasing the risk of illness and disease later in life and so much more. A great way to add sun exposure into your daily routine is by taking a brisk walk outside after lunch with at least 40% of your skin exposed. During the winter, it is extremely important to be diligent with supplementation because it may be challenging to get adequate doses of sunshine on the skin. You may even find yourself sleeping better at night, waking up more refreshed in the mornings, as well as experiencing signs of a stronger immune system after implementing this important habit into your lifestyle.
If you are interested in learning more about how sunshine and our other necessary lifestyle components outside of just training and nutrition can support you in your personalized health and fitness endeavors, click the link below to schedule a strategy session with a Central Athlete coach today!
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