By Marc Sorenson, EdD, Sunlight Institute
Nearly all research shows a positive association between sunlight and bone strength. One of the most interesting of these studies measured heel-bone stiffness (a measurement of bone strength) and various lifestyle factors among Okinawan men with and without type-two diabetes.[i]
The research demonstrated that among the group with type-two diabetes, there were a significant negative correlation between cigarette smoking heel bone stiffness. That negative correlation also was evident with age. Other factors did not produce a significant correlation in the diabetic group; however, in the non-diabetic (control) group, a significant positive correlation was shown between heel-bone stiffness and two other factors: (1) sunlight exposure and (2) consumption of small fish. Of the two, sunlight exposure predicted greater bone strength.
It is probable that the vitamin D produced by sunlight exposure led to increased heel bone strength in the control group. It is also possible that lack of sunlight in the diabetic group may have been one of the predisposing factors that initially led to diabetes in the diabetic group, as it has been shown that vitamin D supplementation in pre-diabetic subjects predict a dramatically reduced risk of developing the full-blown disease.[ii] Sunlight exposure, of course, is the most natural way to produce vitamin D.
Keep your heels—and the rest or your bones—strong by obtaining plenty of non-burning sunlight!
[i] Michiko Gushiken, Ichiro Komiya, Shinichiro Ueda, Jun Kobayashi. Heel bone strength is related to lifestyle factors in Okinawan men with type 2 diabetes mellitus. J Diabetes Invest 2015; 6: 150–157
[ii] Pittas, A. et al. The effects of calcium and vitamin D supplementation on blood glucose and markers of inflammation in nondiabetic adults. Diabetes Care 2007;30:980-86.
The article is a must read for those who want to know more about the influence of sunlight on one of the world’s fastest growing and most dangerous diseases.
By Jeanne D’Brant–
The long, hot summer is here and the sandy beaches of Long Island await our pleasure. An afternoon spent challenging the salt and spray of the south shore or quietly sitting by a north shore beach do more than relax us and put us in touch with nature.
Did you know that the amount of sunlight that you get is a major factor influencing your risk for developing diabetes? Convincing research has shown that the further you live from the equator, the greater your chances are of developing diabetes. In Finland, the risk is elevated 400 times! In 2010, a study in Germany concluded that providing adequate levels of Vitamin D for the German population could save that country a whopping 40 billion in health care costs. The good news for Long Island, by the way, is that we are not at similar latitude to most of Europe. At 41 degrees north, we are on the same latitude above the equator as Istanbul!
Vitamin D is an essential hormone that the body makes when skin is exposed to sunlight. It is created in as little as 15 to 30 minutes, depending on your age, skin color and the time of year. Long known to be essential for calcium absorption and bone health, Vitamin D is now known to play an important role in protecting not only against diabetes but also cancer, tuberculosis, autoimmune diseases and even the common cold. Sunlight on the skin has also been shown to reduce inflammation levels in both healthy people and those afflicted with diseases such as rheumatoid arthritis.
One way that Vitamin D lowers diabetes risk is by protecting the insulin-making beta cells of the pancreas, dampening inflammatory immune signals and boosting antioxidant protection. When the skin makes vitamin D, it produces antioxidants within it to deactivate the free radicals formed by the sun’s UV radiation. This is a natural defense mechanism, a built in sunscreen. Cells also use vitamin D to directly regulate genes, including longevity genes, making it one of the most powerful compounds known in human health. Fortunately, 20 minutes of whole-body exposure to the sun can produce thousands of IUs of vitamin D, and other compounds called FIRS which have important health benefits. One study of 2100 female twins showed that having adequate vitamin D slowed the aging process, improved chronic stress levels, and extended life by five years.
* The skin of anyone 40 or older has lost much of its ability for vitamin D activation. From the point of view of evolutionary biology, by 40 we’ve pretty much had our opportunity to reproduce and make our contribution to the species: we’ve exhausted our reproductive usefulness. Vitamin D turns on genes such as the SIRT and CLOCK genes associated with longevity. Sunscreens, unfortunately, inhibit 98 percent of vitamin D production. Anticonvulsants, steroids and cholesterol-lowering medications all interfere with vitamin D metabolism. Supplementation is recommended for the aging and those taking these medications. In a very large Finnish study, infants and children who consistently took 2000 IU of vitamin D per day had a 78% reduced risk of type I diabetes.
How can you tell if you have enough Vitamin D? Your doctor can order a simple blood test called 25-OH that will show your level. Levels in the 20s are frighteningly low, numbers above 40 are more desirable, but some researchers think our levels should be 65 or more for maximum impact on the genes. If you choose to supplement, what is the recommended dose? We’ll look at supplementation facts in a future post.
Medical treatment of Vitamin D deficiency involves megadosing (50,000 units or more) once a week for six or more weeks, but many clinical nutritionists consider this strategy ill-advised. Vitamin D is known to increase absorption of heavy metals such as strontium in addition to calcium. A more prudent approach might be supplementing in the colder months and enjoying more time outdoors in the spring and summer. Remember, the human gene pool changes very slowly. While human life emerged 5 to 7 million years ago, we started living indoors less than forty thousand years ago, the blink of an eye in evolutionary terms! Current teens and twenty somethings, who spend a majority of their time indoors, are the first generation since the early 1900s to be shortening their lifespan because of their diabetes-creating lifestyle.
So turn it on in the sun this summer! Move around when outdoors, take a hike on the beach, practice safe sun, and soak up some rays as nature intended. Whether you’re spending the day at Jones Beach or Robert Moses, when the waves and the light are working their magic on you, remember that you’re helping your health in numerous ways. Not only are you allowing the relaxation response, which lowers your blood pressure and quells the raging flow of stress hormones, you are also lowering your risk for the blood sugar disorder which is a leading cause of strokes and heart attacks, the #1 killer of the Americans today.