Vitamin D, the Sun and why we’re not
getting enough of both.
Often, but not too frequently, new health paradigms come along that seem counterintuitive to nature. And given enough time, along with approval of the prevailing economic and political interests, they become entrenched in society, and then very difficult to dislodge. So engrained it becomes, that it becomes a part of our regular vernacular. It becomes small talk at the dinner table and our local P.T.A. meetings.
Take for instance our exposure to sunlight, or our lack of it. For if you haven’t heard, sun exposure causes skin cancer. Or unless you haven’t been around in the past decade, you obviously have not been aware of the epidemic of skin cancer that is affecting our citizens. There are countless numbers of public service announcements and also television advertisements from sun tan lotion manufacturers warning you of exposure to these so-called harmful rays of the sun, Ultraviolet A and B to be exact. Not putting sunscreen on a child is seen as tantamount to child abuse!
Well, I am here to tell you that what you have been hearing is not entirely correct. In fact, I am telling you that regular moderate exposure to sunlight is not only a requirement for a healthy life, but also a requisite for living. Much of what I am telling you is from the book “The U.V. Advantage”, written by Dr. Michael Holick, Ph.D., M.D. I highly recommend that you purchase this book (Amazon.com $13.97) and read the facts for yourself regarding sunlight exposure. Dr. Holick is the Director of the General Clinical Research Center at Boston University. He is also Professor of Medicine, Dermatology, Physiology, and Biophysics at Boston University. He has been in the forefront of research into Vitamin D and sunlight. He was the first to discover its production in the body by means of sunlight exposure in the 1970’s.
The preface to Dr. Holick’s book begins: “It happened again the other day. I was in a hotel elevator and overheard a woman telling her companion how much she loved to be in the sun but she couldn’t anymore because ‘it would kill her.’ It’s the kind of thing I hear all the time, and it is what inspired me to write this book.” In the summer of 1997, Dr. Holick performed a study that was later published in the scientific journal, Lancet. His study showed that in a random sampling of people living in the Boston area, fully 42% were vitamin D deficient. This has been referred to as the “silent epidemic.” You will find out how important Vitamin D is to your health later in this article.
Your best dietary sources of vitamin D are oily fish (Salmon, Mackerel, Cod liver oil), which are not typical staples in the average American diet. What about milk you say? We’ll talk more about that also later on. Your best source of Vitamin D is through regular moderate sun exposure. Vitamin D is produced when UV radiation hits your skin and converts an inactive form of D into the active vitamin D molecule. A few, of the more than 200 scientific studies Dr. Holick has written, have focused on evaluating sunscreens and he has found that a Sun Protection Factor (SPF) equal to 8, decreases Vitamin D production in the skin by 97.5% and an SPF of 15 by 99.9%. How bad can the sun be for us if we need it to produce vitamin D?
What does Vitamin D do anyway? Vitamin D is a hormone that is essential for calcium absorption and utilization in the body and for proper bone growth. Bone health equates to decreased fractures, which are one of the main causes of death and disability in seniors. The pediatric bone deformity disease Rickets is one consequence of not enough vitamin D in children. Rickets is unknown in children who get enough sun exposure and is the one of the most effective ways to treat kids. Unfortunately, Rickets, which was once common in the dark, polluted city streets of old industrial Europe, is on the rise in our society again. Adults are not immune to vitamin D deficiency diseases such as Osteomalacia (mild bone loss) and Osteoporosis (severe bone loss). Osteoporosis is endemic and affects 25 million Americans a year. Every year 1.5 million Americans with osteoporosis suffer fractures. Of those fractures, 300,000 are hip fractures and of those, 20% will die within one year and 50% will never regain their mobility and be placed into nursing homes. “Osteoporosis can be mitigated by regular sun exposure.” States Dr. Holick. Vitamin D deficiency also has links to heart attack, stroke, and most internal cancers such as cancer of the breast, colon, prostate, ovary, bladder, uterus, esophagus, stomach and rectum.
It has been estimated that increasing sun exposure would result in 185,000 fewer cases of internal cancers and 30,000 fewer deaths. Sunlight also dramatically reduces high blood pressure (which leads to stroke and heart attack) similarly to medication without the side effects. Sunlight has been found to have a beneficial effect on heart health equal to exercise. Sunlight has also been found to boost your beta-endorphin “feel good” hormone levels, which explain why you feel good after spending time in the sun at the beach, pool or even in the tanning bed. It elevates your sense of well being similar to a “runner’s high.” It also helps control your biological clock which helps regulate mood. It is also associated with decreased rates of depression associated with seasonal affective disorder (SAD) and PMS in women. Despite all these benefits, the health downside is non-melanoma skin cancer.
Non-melanoma skin cancer, which may be caused by long-term sun exposure, has an extremely low death rate. Less than one-half of one percent die. That equates to 1200 lives per year in the U.S. Compare that to diseases that can be prevented by regular sun exposure and have 20%-65% mortality rates and kill 138,000 Americans annually. From a public health standpoint, non-melanoma skin cancer is relatively unimportant. I would never trivialize skin cancer as unimportant on those who have it. I am a native Arizonan and I have the unique position of having had non-melanoma skin cancer myself, but in public health terms, it is relatively unimportant.
What about Melanoma? 80% of all skin cancer deaths are attributed to melanoma. However, there is no credible scientific evidence that moderate sun exposure causes melanomas. Melanoma is more often seen in people who do not receive regular moderate sun exposure and it usually occurs on parts of the body that receive no sun exposure. In the 60’s and 70’s early sunscreens only afforded UVB protection and it is thought that this encouraged people to spend more time outdoors, thusly receiving more UVA exposure, which has been linked to melanoma. Nowadays, most sunscreens block UVA/UVB radiation. Or do they? Recent research is showing that they are not very effective at blocking UVA radiation, especially when the sun is at it’s greatest intensity; Researchers found that even sunscreens with the highest sun protection factor of 35, applied in the correct amounts, were not effective at filtering out harmful UVA rays. Some experts believe that this disturbs the normal ratio of UVA/UVB exposure and can contribute to melanoma development. UVA rays penetrate deeper into the skin than UVB. UVB rays are what causes you to tan and produce Vitamin D.
What about milk? For those of you who would rather just avoid the sun and drink more milk fortified with vitamin D. Much of the milk sold today does not actually contain the vitamin D it is supposed to. Dr. Holick published a study in the New England Journal of Medicine, which proved this. Further studies and one by the F.D.A have since backed it up. Vitamin D fortified whole milk contained less than 20% of what was stated on the label, half (2% milk) contained less than 50% of vit. D and 14% of the skim milk samples contained no detectable vitamin D. Even if milk had what it was supposed to have as far as vitamin D goes, which is 100mg per serving, you would need to drink ten glasses a day to get the required 1000mg of vitamin D. that Dr. Holick recommends adults get.
So what should your relationship be with the sun? It depends on many factors such as your skin type, your age, your latitude, the time of day, the season, your ethnicity, (darker African descent skin is more protective of the sun and therefore it is harder for you to get your required amount for ample production of vitamin D), and your dietary status (certain types of diets such as high animal fat can increase your chances of developing certain skin cancers, while other types of fats such as omega-3 fish oils are protective). I recommend highly that you purchase this book and look at all of the information. Dr. Holick talks about achieving 20%-25% of your 1MED (minimal erythemal dose) to achieve 1000mg of vitamin D. Your 1MED is the amount of time it takes you to achieve a light burn (pink). He recommends that you expose your arms, hands and face (or arms and legs) daily for 20%-25% of that time. That may be as little as 2-4 minutes in the middle of the summer in Phoenix, Arizona. You should never burn! Burning can and will lead towards skin damage and cancers.
Your body has extensive mechanisms for dealing with sun exposure damage. You have a unique set of enzymes in the cells of your skin that do nothing but repair damage to your cellular DNA caused by UV radiation. Also, specialized cells called melanocytes increase in size and cause your skin to darken by producing pigments the more your are exposed to sunlight. They offer great protection against UV radiation. That is your body’s natural defense against UV rays. However, if you overwhelm your skin and burn, you can set yourself up for skin cancer and other damage.
A good plan for summer sun exposure is early in the season, get regular moderate sun exposure. Never burn, but build up a resistance. Once you achieve 20%-25% of your 1MED, get out of the sun or cover-up. The time you can safely spend in the sun without protection will increase the more you build up your natural protection. It is also advised that you eat a lot of whole vegetables (antioxidants), increase your omega-3 fatty acids (and reduce omega-6 fats, see my previous newsletter) which are protective for skin cancers and reduce your trans-fatty acids by eliminating partially or fully hydrogenated oils from your diet.
Just a short note on the use of sunscreens. I am not a fan of sunscreens. Your skin is the largest organ of your body and I am hesitant of slathering chemicals onto it. Sunscreens can be broken into two major categories. Inorganic sunscreens like titanium and zinc oxide that act to reflect/scatter UV rays (physical blockers) away from your skin. There are also organic chemical sunscreens that absorb UV light. Sunscreens should be treated with caution, and used only when it is impractical to stay indoors or to shield the skin from the sun with clothes. The jury is still out in my opinion whether these chemicals are harmful. There is evidence that your body does absorb these chemicals, organic and inorganic, and that they have been shown to affect animals negatively in laboratory studies. Of recent concern are questions that most organic chemical sunscreens mimic the effects of estrogen hormones and trigger developmental abnormalities in rats.
If you must use sunscreens, look
for more “natural sunscreens” which are available at holistic health stores. Some natural sunscreens use plant oils such
as sesame, coconut, peanut, olive and cottonseed oils, which are natural
sunscreens and block between 20%-30% of UV rays. You can find more about Dr. Holick and explore some of the myths
and truths of sun exposure on his website at the UVadvantage.com. Another good
resource for natural health information is Dr. Joseph Mercola’s website at
Mercola.com
In closing, our risks for developing skin cancers may have
already been “set in stone” many years ago during sun over-exposure in our
early childhood and adolescent years.
What is most important now is to change your relationship with the sun,
improve your diet/nutritional factors, see a dermatologist, get regular
moderate sun exposure, and never burn.
Do not be afraid of the sun, for man has had a beneficial relationship
with the sun for many thousands of years.
“The notion that we have to protect ourselves from the sun all the time is misguided and unhealthy. This sun phobia explains why so many people are suffering from conditions related to sun deprivation” “Your overall well-being depends in part on developing an appropriate relationship with the sun.” - Dr. Michael Holick