VITAMIN D3 AND OSTEOPOROSIS Compiled for my own use from research of others by Katy Casey. Vitamin D3 (cholecalciferol) and Vitamin D2 (Ergocalciferol) are not the same. Almost all our current toxicity data relates to Vitamin D2, which is a synthetic analogue of Vitamin D3 and has different characteristics. Actually, Vitamin D2 shouldn't even be called a vitamin and its data on toxicity doesn't even relate to Vitamin D3. Yet info offered by the FDA, The Food & Nutrition Board of the Nat'l. Academy of Sciences and doctors and pharmacists are using data from Vit D2 and relating it to Vitamin D3. Continuing to use Vit D2 as a model for discussing our need of Vit D3 is neither accurate nor helpful. Our bodies use of calcium is directly tied to Vitamin D3. And PTH (Parathyroid Hormone) is also involved. Inappropriate calcium activity in our bodies is absolutely involved in all the major degenerative diseases. Cancer, heart disease, multiple sclerosis are all impacted with this, but following info is regarding osteoporosis. Circulating PTH is elevated in people with osteoporosis. In fact, one of the "new" drugs for osteoporosis inhibits excess PTH. High serum levels of PTH means the parathyroid glands are overactive and the glands often grow tumors that are then fodder for surgical removal. Surgery and drugs address symptoms, ignoring that hyperparathyroidism is found to be secondary to Vitamin D3 deficiency. The parathyroid glands get pretty tired from being overworked. They are in a continual state of overwork if we run around living our lives in a state of deficient Vitamin D3. Its not unusual for this condition to take 30 or more years to manifest in actual diagnosed disease. Osteoporosis is but one of them. There are serum and urine tests that are useful in learning more about all of this. One standard blood test is called "serum 25-hydroxyvitamin D3 level", called serum 24(OH)D for short. This test assesses blood levels of D3. To put it another way: Serum 25(OH)D concentration seems to be the appropriate measure of Vitamin D nutritional adequacy, and it takes 4,000 IU daily (that's 100 mcg) to ensure that serum concentrations of 25(OH)D exceed 100 nmol/L. A urinary test calculates the ratio of urinary calcium to urinary creatinine, and that ratio should be less than 0.37. Ratios that consistently stay above 0.37, indicates excess urinary calcium. The 24(OH)D serum test in most Americans probably runs around 50 nmol or less per liter. (nmol is a nanomole, an "atomic physics" lingo type word describing a very tiny mass being measured). We want our serum 24(OH)D test to result in something between 75 and 100 nmol/L. if we hope to stay healthy. If we already have osteoporosis, we want our serum 24(OH)D test result to be very close to or just over 100 nmol/L for a few months running in order to reverse the bone remodeling that is going on and get back to bone health. Then we adjust our Vit D3 intake to keep our serum 24(OH)D level above 80 nmol/L as an everyday state of health. Canada's Food & Nutrition Board of the Nat'l Academy of Sciences did some testing and decided that the LOAEL (lowest adverse effect level)...in other words, the amount you can take with no toxicity...is 95 mcg/day, which is equivalent to 3800 IU/day. Yet...the RDA in Europe is set at 200 IU/day and an Vitamin D pill in the U.S. is often 400 IU. Yet, a day in the sun with full body exposure gives one more like 10,000 IU/day. A day in the sun is a rule of thumb for obvious physiological tolerance without toxicity. So we see disagreement between country's food recommendations, sun exposure sources, and known diseases involved with D3 deficiencies using blood/urine tests for verification. It seems obvious that a daily intake or 400 IU or even 800 IU is not only not adequate, it is deficiency. It seems much of the world is Vit D3 deficient with diet and sunshine playing major roles. One teaspoon of cod-liver oil given to infants contains 400 IU/day to prevent rickets. The adult equivalent of this prevention dose for babies is 4000 IU/day Some groups with known low sun exposure (veiled women, men in submarines, far no. latitude populations) were tested. They were given 1,000 IU/daily of Vit D3 and their PTH was yet found to be high, but lower than ones without the D3 supplements. These tests found that except in those with hypersensitivity, there is no evidence of adverse effects with serum 25(OH)D concentrations that remain under 140 nmol/L. As PTH (parathyroid hormone) circulation increases with decreases in 25(OH)D and because a suppression of PTH is seen to be beneficial for bone, many now regard serum 25(OH)D concentrations of more than 75-100 nmol/L as desireable. Prolonged consumption of Vit D3 at a dosage of 100 mcg/per day (this is 4000 IU/day) results in a serum 25(OH)D plateau of 96 nmol/L. If a person already has some osteopenia or osteoporosis, higher numbers are needed for a month or two to get all rolling back into health, get blood tests, and work towards normalizing into year-around levels of 80 nmol/L for ongoing health. Reinhold Vieth is currently conducting POWDER studies in Toronto (Prevention of Osteoporosis With vitamin D - Evaluation of Responses), supported by Canadian Institutes for Health Research His research completed the first phase which proved higher vitamin D intakes are safe (this is opposite to the conclusion of current food guidelines). The POWDER study is aimed at answering the question, "if you are a postmenopausal woman who has had bone density done, and it is reported back to you as normal, will a physiologically natural supply of vitamin D slow down the progression of bone loss?" Volunteers are randomized to receive vitamin D3 in a daily dose that what works out to either 800 IU or 4200 IU. Additionally, this research has been published in Dec 2001 European J Clin Nutrition that the "officially recommended" intake of Vit D cannot be detected in the blood so higher doses are needed. This POWDER study hopes to prove if more than 800 IU/day will offer any added benefit and may even yet be seeking participants (Canadian only). In summary, there seems to be overwhelming evidence to show deficiency of Vit D3 causes disease, and research will now prove if additional supplementation actually work to prevent osteoporosis. As I have diagnosed osteopenia, my own health plan is to seek a provider who will agree to run the appropriate serum and urine tests described here. Then I'll take the larger doses of Vit D3 and see how it goes. Because I'm just barely into having osteopenia, I seem to have that opportunity of time to use myself as a willing gineau pig and see what effect this may have on my own DEXA scores. Bibliography: 1. R.Vieth, PhD., Canadian Medical Assoc Journal, June 2002 2. Reinhold Vieth, Eur J Clin Nutr, Dec 2001 3. Reinhold Vieth, American Journal of Clinical Nutrition, May 1999 Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.