We were taught in school that Vitamin D deficiency had been wiped out in the early 1920s and 30s.
However, Michael Holick, MD, PhD at Boston University, says that vitamin D plays a key role in preventing osteoporosis, prostate, breast, and 11 other cancers—all of which have increased dramatically due to vitamin D insufficiency. It’s not just cancer and osteoporosis. Hypertension, diabetes, cardiovascular disease, multiple sclerosis, rheumatoid arthritis, chronic pain, and inflammatory bowel disease are also on Professor Holick’s list. Unfortunately, some of the things the “experts” have been telling us to do for years (in the name of good health and, of course, safety) have actually made the situation much worse.
Vitamin D itself was “discovered” in the early 20th century after generations of rickets outbreaks were traced back to extreme deficiencies of this vitamin. But, unfortunately, instead of emphasizing sunlight exposure—nature’s major source for Vitamin D in humans—researchers, physicians, and public health “authorities” took a wrong turn years ago and started recommending Vitamin D ”fortified” food as the major source. (Of course, food manufacturers certainly weren’t going to argue, since they would make more profit making and recommending Vitamin D enriched food than by emphasizing sunlight exposure.) Sunscreen is actually causing Vitamin D deficiency.
Vitamin D: Hypertension, Cancer and Osteoporosis
In the 1940s, researchers observed a higher incidence of hypertension, colon, prostate, and breast cancers in people living in temperate latitudes. At the time, they couldn’t fully explain the connection, but eventually they realized that temperate zones get less sunlight, which means the people living there get less vitamin D.
Then in 1989, researchers reported that adults with higher levels Vitamin D have 50% less risk of colon cancer. Since then, numerous studies have found that Vitamin D actually inhibits the proliferation of cancerous prostate, breast, bone, and skin cells as well. But a significant proportion of “essential hypertension” (hypertension of unknown cause) can probably be traced back to Vitamin D deficiency.
Autoimmune Disease and the Risk of Type 1 diabetes drops by 80% with Vitamin D
Then in 1989, researchers reported that adults with higher levels (above 20 ng/dl) of 25-hydroxyvitamin D have 50% less risk of colon cancer. Since then, numerous studies have found that Vitamin D actually inhibits the proliferation of cancerous prostate, breast, bone, and skin cells as well.
Insufficiency or Excess of Vitamin D
So with all the research in favor of Vitamin D, how can you be sure you’re getting enough—but not too much? Well, the best source of Vitamin D—sunlight—actually has two built-in “overdose indicators.” The first is sunburn. When you start to get slightly pink, you’ve reached the limit of safe Vitamin D. And you’re not likely to go out in the sun again until your pinkness subsides. Tanning is the body’s other built-in Vitamin D regulator. Increasing pigment in the skin blocks the formation of Vitamin D. So the more you tan, the less Vitamin D you get. With sunlight being nature’s preferred Vitamin D “delivery system,” there’s no chance of overdose.
Vitamin D Testing
The correct test to monitor Vitamin D is 25(OH)D, also called 1,25 hydroxyvitamin D. Normal values are 25-56 ng/ml. Any levels below 20 ng/ml are considered serious deficiency. Ideal is above 70.
Vitamin D Supplementation
If you take a Vitamin D supplement, it is wisest to monitor your serum level of 25-hydroxyvitamin D. The active form of Vitamin D is 1,25 dihydroxyvitamin D and that is the best one to evaluate vitamin D but it is more expensive. Dosage recommendation may vary from 5-10,000/ IU for therapeutic purposes for adults, with maintenance at 3,000 I.U. to 4,000 I.U. daily. For children, the diabetes-prevention studies used 1,000 – 2,000 I.U. daily.
If you’re past 35, it’s probably a good idea to consider taking up to 4,000 IU daily to help prevent osteopenia and osteoporosis. This is especially important if you have a family history of this problem.
- Garland CF, Comstock GW, et al. Serum 25–hydrocyvitamin D and colon cancer: eight-year prospective study, Lancet 1989; 2(8,673: 1,176-1,178
- Li YC. Vitamin D regulation of the renin- angiotensin system. J Cell.Biochem 2003; 88(2): 327-331
- Hypponen E, Laare E, Reunanen A, Jarvelin MR, Virtanen SM. Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study. Lancet 2001; 358(9,292): 1,500-1,5003
- ibid. 5. Veith R. Vitamin D supplementation, 25¬hydroxyvitamin D concentrations, and safety. Am J Clin Nutr 1999; 69: 642-856 6. Veith R, Chan P-C R, MacFarlane G D. E cacy and safety of vitamin D3 intake exceeding the lowest adverse e ect level. Am J Clin Nutr 2001;