Sunday, August 28, 2016

The Facts on Safe Sun Exposure and Vitamin D

If you are confused about whether exposure to the sun is good or bad or somewhere in the middle – you are not alone!   There is a ton of conflicting advice and information being given on Sun Exposure.   On the one side we are being told to completely avoid all sun exposure and wear heavy duty sun screens at all time and on the other being told that sun exposure is vital and good for us.
As always the real answer is somewhere in the middle and it is critical to evaluate the validity of information you receive based on the source and if they have a commercial stake in the information they give you.   For example it is not at all surprising that sun screen manufacturers are pro sun screen and push the concept that everyone should wear it all the time to insure they do not get skin cancer, but we know they have a vested commercial interest so should use some judgment evaluating information from these sources.    And yes there is information suggesting that many sunscreens contain chemicals that can be harmful to your health.   It is important to use sunscreens that do not contain toxic ingredients and do block both UVA and UVB rays.    For a great guide check out this article by Dr. Mercola:  http://articles.mercola.com/sites/articles/archive/2014/06/04/ewg-sunscreen-guide.aspx
The fact is that this issue is not so simple as “authorities” would have you believe.  For example in this research article (Avoidance of sun exposure as a risk factor for major causes of death: a competing risk analysis of the Melanoma in Southern Sweden Cohort) that studied all-cause mortality in 29,518 Swedish Woman the conclusion was that avoiding the sun can actually be as dangerous as smoking when it comes to cancer risk and overall mortality risks. Woman who avoided the sun had a much shorter life expectancy than those who got the most sun.   This really challenges the conventional wisdom on sun exposure.   It is also important to state that it is all about dose and your personal genetics meaning that the amount of sun you are exposed to and your personal genetics are very relevant here!
Improving Vitamin D Status is a Key Benefit of Proper Sun Exposure
Sun exposure increases the body’s production of Vitamin D and does so in a way that is quantitatively and qualitatively different and superior to supplemental Vitamin D.    When the body produces Vitamin D from sun exposure it simply will never produce too much Vitamin D and this is not the case with supplementation.    In addition, there are other benefits to safe sun exposure in addition to Vitamin D production.   Proper sun exposure can and does help treat several skin conditions such as psoriasis, vitiligo, atopic dermatitis, and scleroderma.   In addition, sun exposure protects against and suppresses the symptoms of multiple sclerosis, helps relieve fibromyalgia pain, helps treat seasonal affective disorder, enhances mood and energy by stimulating the release of endorphins, and helps synchronize biorhythms and melatonin production.
The Health and Medicine Division of the National Academies of Sciences, Engineering, and Medicine have reported an association between vitamin D and overall mortality risk from all causes, including cancer.   However supplementation studies have been all over the map in terms of showing a positive relationship between boosting Vitamin D status and incidence or mitigation of disease.    Since we know for sure that the human body was designed with the specific capability of producing Vitamin D from sun exposure and we know that Vitamin D levels are crucial for optimizing health it seems quite likely that production of Vitamin D through sun exposure is the ideal if it can be done safely.
There is a lot of positive research on Vitamin D and cancer prevention and treatment, heart disease prevention and treatment, etc..which shows that optimizing Vitamin D is a good prevention strategy.
Vitamin D affects almost every cell in your body, which is one of the reason’s it affects so many different disease states.
Vitamin D from Sun Exposure and Health
There have been many studies done on average vitamin D levels and the vast majority of them have found that at least half of the U.S. population has inadequate levels.
Vitamin D is not really a vitamin – rather it is a steroid hormone that your body is designed to create through sun exposure, not from your diet. While some foods do contain vitamin D it is nearly impossible to get all the vitamin D you need from dietary sources alone.
The U.S. Surgeon General American Academy of Dermatology recommend complete and total sun avoidance in order to prevent skin cancer, and there is no question that overexposure to sun can and does cause skin cancer at some level.    However sun avoidance has been shown to increase your risk of death from all causes substantially so this recommendation does not make the most sense.
Optimizing Vitamin D through Safe Sun Exposure
By following sensible sun exposure rules, including making sure you do not get burned, you can maximize the benefits and minimize the risks of skin damage that could lead to skin cancer. Overexposure, not completeky avoiding the sun, is the real issue for increasing your risk for skin cancer.  At the same time, optimizing vitamin D through regular sun exposure can decrease your risk of many forms of cancers that are far more common than Melanoma which is the deadliest form of skin cancer.
So how much sun exposure is enough?
The answer depends on your skin type, time of year, time of day, and where you are located!  The closer you are to the equator the less time you need in the sun because the sun is stronger and more UVB rays hit your skin (UVB is the key to Vitamin D).     Depending on your location time of year can be very important.   For example in the Northeastern US you cannot get enough sunlight exposure during winter to make sufficient amounts of Vitamin D for optimal health (one of the reasons people tend to get sick more in the winter).  Time of day is also important.  Ideally mid-day sun provides the highest level of UVB light BUT you also need much less sun exposure and it is much easier to burn!
As mentioned above your skin type is also important!  There are technically 5 skin types as it relates to sun exposure times: Type I – White; very fair; red or blond hair; blue eyes; freckles Type II – White; fair; red or blond hair; blue, hazel, or green eyes Type III – Cream white; fair; with any eye or hair color; very common Type IV – Brown; typical Mediterranean Caucasian skin Type V – Dark Brown; mid-eastern skin types Type VI – Black
If you are skin type 1 to III, you will produce vitamin D more quickly than if you have skin type IV to VI.      A simple rule is to obtain half the sun exposure it takes your skin to turn pink (NOT BURN).     This will tend to optimize benefits without risks.   The more skin you can expose the better!   Once you have been in the sun this long you should cover up – actually covering up is ideal versus using sunscreen.    So wearing hat shirt and pants made out of a light but UV blocking material is ideal if you are going to be outside longer than half the time it would take for your skin to turn pink.
According to the National Institutes of Health, between five and 30 minutes of sun exposure to your unprotected face, arms, legs or back between the hours of 10 a.m. and 3 p.m. two to three times every week is enough for your body to produce all of the Vitamin D it needs. So for extremely fair people during peak summer or live close to the equator just 5 minutes of mid-day sun is all it takes, but for a person with dark skin who lives farther from the equator it is probably more like 30 minutes.    Now the key is NOT to burn so start with less time and gradually increase it!

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