There has been considerable interest and debate in the scientific community regarding the recent recommendations of the IOM (Institute of Medicine) as it relates to the proper intake of vitamin D. Commenting only on the relation to bone health, the IOM panel called for 600 IUs of vitamin D daily for all ages up to age 70 and 800 IUs after age 71. They also doubled the UL (safe upper limit) to 4000 IU per day.
These dosage recommendations were based on what the panel believes would allow most individuals to maintain a vitamin D blood level of 20 ng/ml.
Many internationally recognized vitamin D researchers, including Creighton’s Dr. Robert Haney feel these recommendations are too low:
“The statement by the IOM that skeletal health can be maintained at serum 25(OH)D levels of 20 ng/ml is incorrect. 30 ng/ml should be looked at as the lower end of the acceptable range for bone health. There have been randomized controlled trials showing major reductions in fractures by getting the serum level to 29 ng/ml. Fracture reduction does not reliably occur at levels less than 30 ng/ml and in some cases as high as 40 ng/ml. Osteoid seam width, a measure of vitamin D deficiency, only reaches normal values when the level is above 30 ng/ml. There is significant evidence above the IOM panel’s “adequate” level of 20 ng/ml.”
Dr. Walter Willett, the chairman of the nutrition department at The Harvard School of Public Health and a member of the Cooper Complete Nutritional Supplement scientific advisory committee agrees that the IOM recommendations are too low:
“We don't have all the evidence, but the data are clear that blood levels higher than 20 ng/ml are associated with higher BMD (bone mineral density), a strong risk factor for fracture. The main evidence used to set the level at 20 was from a study of osteomalacia in an autopsy series. Osteomalacia was not associated with age, which makes it a dubious sufficient indicator of bone health.”
In contrast to the IOM report, the IOF (International Osteoporosis Foundation) recommended in their 2010 position paper on vitamin D a threshold of 30 ng/ml for optimal fall and fracture reduction.
It is also very important to note that vitamin D levels are associated with much more than just bone health. There is tremendous data in the scientific literature showing a clear relationship between deficiencies of vitamin D and many cancers, including breast, colon, ovary, and kidney. In fact, Dr. Cedric Garland from the Moores Cancer Center at U.C. San Diego has stated that, “the benefit of vitamin D is as clear as the harmful link between smoking and lung cancer.”
In addition to many cancers, vitamin D deficiency has also been associated with cardiovascular disease, diabetes, immunity to infection, multiple sclerosis, age related macular degeneration and chronic pain.
The Cooper Clinic bases vitamin D dosage recommendations on a patients actual blood level (25(OH)D). Ideally we strive for individuals to maintain a serum level of between 40-60 ng/ml with 30 ng/ml considered to be an absolute minimum. The Clinic has been measuring vitamin D levels in our patients since May, 2007 and we know two things are certain. One is that the majority of first time patients fall below, some well below, the 30 ng/ml minimum target and, the dosage needed to achieve sufficiency varies greatly from patient to patient.
For over 40 years Cooper Clinic has focused on preventive medicine and we base all of our recommendations on the preponderance of published scientific evidence. This is why all of our adult formulations of Cooper Complete multivitamins contain 2000 I.U. of vitamin D-3. For many that amount is adequate to achieve and maintain a vitamin D blood level of at least 40 ng/ml. However for others that only serves as a starting point. I have several patients that need to take 3000-4000 IU of vitamin D-3 daily and some require 50,000 IU/week in order to maintain adequate blood levels. The important point is that one size does not fit all. Of note Dr. Michael Holick, an internationally recognized vitamin D researcher from Boston University has conducted studies giving subjects 50,000 IU of vitamin D twice a month for six years and has seen no harmful effects.
Should you have an interest in exploring the vitamin D topic in greater detail I encourage you to visit www.grassrootshealth.net or e-mail Todd Whitthorne, President and CEO of Cooper Concepts, at twhitthorne@cooperwellness.com. He can also be reached at 972-560-2656.
Sincerely,
Kenneth H. Cooper, M.D., M.P.H.
Founder, CEO, Cooper Clinic
I believe there's only a certain amount of vitamin D that we should take. Whether we take supplements or go under the sun, it's still important to take enough of the vitamin.
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