There’s really no controversy. The sheer number of articles showing up in the press and other media is staggering. The need for a new RDA on Vitamin D is obvious, yet still many physicians are reluctant to replete deficiencies with the correct amount.
The fact that a world wide Vitamin D deficiency pandemic is a reality has been recognized by just about every major health organization including the WHO; World Health Organization, the NIH (National Institutes of Health) and many others. The far reaching implications of the deficiency which affects millions of adults and children in just about every country has finally attracted media attention. Articles have appeared repeatedly in professional medical journals, magazines, in the press and other media for more than the last five years. One of the best articles can be found in the New England Journal of Medicine, July 19, 2007 by Dr. Michael Holick. Why has it taken so long? In 1997 The Institute of Medicine that set the RDA decided there was insufficient evidence at that time to raise it from 400 i.u per day.
How much is enough? The RDA is the “recommended daily allowance” and the FDA regulates the amounts that can be put into nutrients; you’ll find them listed on a label of vitamins. Although the RDA for Vitamin D is still only 400 i.u. per day, that is only an amount that will keep you from showing the effects of an actual deficiency, but it is not an amount that will guarantee optimal well-being. It may still be too low to prevent deficiency disease in many people; such as those with poor absorption of oil soluble vitamins. Many people who are getting 400 i.u. are at risk for developing long latency diseases, and auto-immune diseases like diabetes, multiple sclerosis, cardiovascular disease, and have an increased risk of cancer. Though research back into the 90’s showed that that RDA is woefully low, it has not yet been changed. Federal agencies are slow to change even in light of new, well-documented scientific information. It’s also true that new information does not always change the beliefs of educated people and doctors may still cling to what they learned years ago, despite the fact that the old scientific information has already been refuted. This doesn’t just apply to Vitamin D, but to surgical procedures, pharmaceutical agents, and protocols for treating different diseases.
Unfortunately what that means to you, the patient, is that many medical and other health care providers including prominent newspaper columnists, are still promoting the wrong dosages. They are still scaring people about safe sunlight exposure or the possible toxicity of Vitamin D. An excellent reference every one should read is Dr. Michael Holick’s book, THE UV ADVANTAGE. He is one of the foremost researchers on Vitamin D, having discovered the circulating form of the active hormone form of the vitamin; 1, 25 (OH) D3. In this book, which is worthwhile for doctors and patients alike, he goes over the dosages, safe sunlight exposure, and explores the real risk of hidden cancers that is much higher, than those that are only related to visible skin cancers alone when D levels fall too low.
The new recommendations by the foremost researchers on Vitamin D are saying that 1,000-2,000 i.u per day is what adults need for maintaining well being. The low risk of toxicity and the signs of it are also gone over in Holick’s book above, but it is exceedingly rare. At the end of this blog, you can click on the url’s and sites for more information, find articles, and references to satisfy your curiosity. Printing it and taking it with you to your next doctor visit, might help inform your health care provider about the new findings. The serious consequences of Vitamin D deficiency is now coming to light. They include not just bone health/osteomalacia, brittle bone disease and osteoporosis, but increased risk of many kinds of cancer, depression, auto-immune diseases like diabetes, and multiple sclerosis.
Low D levels are associated with the lack of normal immune response which leaves children and adults vulnerable to upper respiratory illnesses and allergy. Every cell in the body has a vitamin D receptor on it, including brain cells. We now know that what used to be referred to as Seasonal Affective Disorder is more likely to be caused by the decrease in D levels that occurs in the dark days of the year, for those who are not appropriately supplementing.
The fear of melanoma and the American Dermatology Association’s crusade against skin cancer, although admirable, has made all of us tend to cover up, stay out of the sun, and use sunscreen which prevents us from making D from sunlight. Let’s put this all in perspective and get numbers on the real risks. The risk of hidden cancers, like colorectal, breast, prostate and others is acutally much higher than that of melanoma. Read on and read up.
Keep in mind that because we are genetically unique individuals, have different metabolic needs, and our activities vary; such as how much we eat from one day to the next, what we eat, the vitamin content of the food we’ve taken in, how much sunlight we’re getting, where we live, at what latitude we live, even if the RDA was changed, your personal needs still might not have been addressed. Your genetic inheritance may or may not predispose you to cancer, but without Vitamin D on board, your risks are still higher.
Working with a Funtional medicine health care practitioner ( www.functionalmedicine.org) who stays up on new scientific publications, and who can write up a lab test for your current D status, is a good place to start. A Vitamin D blood test is inexpensive. The lab slip should be written; 25 (OH) D assay. The test should be done fasting. The interpretation of the result, suggestions about safe sunlight exposure, how much to replete and for how long, should be managed by your doctor.
I recommend annual testing to make sure your levels are where they should be and you shouldn’t settle for having your levels at the low end of normal which is 30 ng/ml but seek to raise it to optimal levels between 60-100. After taking vitamin D under your doctor’s supervision, you should be retested in 3-6 months, and have your blood levels of calcium checked at the same time. For those with celiac disease or other malabsorption syndromes, it may take longer and be much harder to correct a deficiency. People who live in northern latitudes, and places that are foggy or cloudy all the time, should be particularly vigilant. It is very difficult to get enough D from the foods we eat. Really even in cold water fish, the amounts are small. If you are dark complected, you have more melanin ( pigment) in your skin which can very effectively keep you from making D when exposed to sunlight. Many African Americans cannot make D at all at some of the northern latitudes. The higher incidence of high blood pressure, cancers, kidney disease, MS, cardiovascular disease, diabetes and many other long latency diseases in this population are associated with D deficiency.
The research on D, and the cites are too numerous to list. Magazines like TIME, NEWSWEEK, SCIENCE, etc. have all had articles. Medline, PubMed, and many others can provide recent papers. ALTERNATIVE THERAPIES Journal had a “conversations” interview with Dr. Holick May/Jun 2008, VOL. 14, No. 3 pages 65-75.
Here are a few cites:
1. Autier P, Gandini S. Vitamin D supplementation and total mortality: a meta-analysis of randomized controlled trials. Arch Intern Med 2007 Sept 10;167(16):1730-7
2. Lappe JM, Travers-Gustafson D, Davies KM, et al. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Am J Clin Nutr 2007 June; 85(6):1586-91
3. Pittas AG, Lau J. Hu FB, et al. The role of vitamin D and calcium in type 2 diabetes. A systematic review and meta-analysis. J Clin Endocrinol Metab 2007 June;92(6):2017-29.
4. Wagner DL, Hulsey TC, Fanning D, et al. High-dose vitamin D3supplementation in a cohort of breastfeeding mothers and their infants; a 6-month follow-up pilot study. Breastfeed Med 2006 Summer1(2):59-70
5. Holick MF. Vitamin D deficieny. N Engl J Med 2007;357:266-81 PubMed abstract
6. Hayes, CE, Hashold FE, Spach KM, Pederson LB. The immunological functions of the vitamin D endocrine system. Cell Mol Biol 2003;49:277-300. PubMed abstract.
Here are some good places to look for other articles and information resources:
http://nccam.nih.gov/news/newsletter/2006_spring/cal.htm
http://ana-jana.org/jana_journal.cfm
http://health.nih.gov/