If I told you to go out into the sun without sunscreen on a regular basis you would probably think I had lost my marbles. But that is exactly what I am going to tell you. Why? Because research in the last decade proves that people living in the northern hemisphere particularly, have as a population, a significant deficiency of vitamin D. There are countless studies to show this, and many of them come from Dr. Reinhold Vieth at the University of Toronto, as well as Dr. Michael F. Holick at the Boston University Medical Center in Massachusetts.
Studies have also linked vitamin D deficiency to a number of chronic diseases including diabetes, osteoporosis, multiple sclerosis and various cancers including the bowel, prostate, and breast. It's not that the deficiency of vitamin D actually causes these diseases, but that a vitamin D deficiency is strongly associated with them.
Vitamin D used to be recommended in relatively small amounts, and was added to milk in the early part of the last century to prevent the onset of a childhood bone disease known as rickets, that softened the bones of young children. Although the addition of small amounts of vitamin D in food has for the most part prevented rickets, we now recognize that vitamin D is actually needed in much larger amounts.
Vitamin D is actually more like a hormone that it is a vitamin. A vitamin is actually defined as a substance, not made by the body, that must be obtained from our diet and that is vital to our well-being. Vitamin D is certainly vital to well-being, but it is actually made in the body with the help of sunlight, and it is only contained in small amounts in certain foods. The bulk of vitamin D comes from the ultraviolet light action on the skin causing the cells of the skin to make it. Initially this is not its active form, and it must be converted to an active form both in the liver and finally in the kidney before it can act. Once in its active form it is responsible for calcium absorption and bone formation, as well as regulating many other processes in the body.
Here are some interesting vitamin D facts:
The further you live from the equator and the darker your skin, the longer you need exposure to the sun to generate sufficient vitamin D. Ultraviolet light does not penetrate glass sufficiently for the body to make vitamin D, so you actually need to be outside. Having kidney disease or liver damage can impair your body’s ability to activate circulating pro-vitamin D. Osteoporosis is commonly caused by a lack of vitamin D, which impairs calcium absorption. Sufficient vitamin D may help prevent prostate cancer, breast cancer, colon cancer and depression, and low levels have recently been associated with chronic pain. Vitamin D deficency may exacerbate type 2 diabetes and impair insulin signalling. Obesity impairs the action of vitamin D in the body, and obese people need more vitamin D, but they can store more of it in their fat cells and release it when needed. Your risk of developing serious diseases like diabetes and cancer may be reduced 50% - 80% through simple, sensible exposure to natural sunlight 2-3 times each week. Infants who receive vitamin D supplementation (2000 units daily) have an 80% reduced risk of developing type 1 diabetes over the next twenty years.
So how much sunlight should you get? Experts recommend about 10-20 minutes exposure of the head, neck and arms, to sun without sunscreen daily. In the winter, because of the angle of the sun at this latitude, it is impossible to get sufficient vitamin D and it is recommended that everyone take at least 1000 international units per day during the winter. You should of course wear sunscreen after your daily exposure.
That’s the good news! Sun exposure is not all bad, in fact a small amount is needed for good health.