Low carb dieters have emphasized the need for supplements from early on, and one of the supplements growing in importance has been Vitamin D. This is largely due to the growing body of cutting edge research showing its benefits for a wide range of disorders, from asthma to parkinson’s disease.
Drs Mike and Mary Dan Eades recommend regular sun exposure, without sunscreen, in The Protein Power Lifeplan, and the paleo community regularly touts the importance of being outside and active in the sun just like our ancestors. Today’s office dwellers realize their fluorescent lit lives do not allow enough sun time each day, and supplement with vitamin D.
The Institute of Medicine’s (IOM) Food and Nutrition Board (FNB) was asked to look at vitamin D in order to evaluate if the current recommendations, expressed as “Daily Recommended Allowance” (RDA) in health literature, was adequate. After reviewing the current state of the science they surprised all of us by “staying the course” with vitamin D RDA the same as stated by the NIH in 2009 – just 600 IU per day for most people.
Cardiologist Dr. William Davis of the Heart Scan Blog commented:
Instead of a careful, science-minded conclusion that meets the painfully conservative demands of crafting broad public policy, the committee instead chose to dogmatically pull the discussion back to the 1990s, ignoring the flood of compelling evidence that suggests that vitamin D is among the most important public health issues of the age.
How can this happen when so much has been discovered about this important vitamin in the last few years? With possible implications for asthma, autism, auto-immune disorders, cancer, depression and mental illness just to name a few, its hard to understand the findings. Even my family practitioner commented to me that sunscreen may have caused more cancer than it prevented by blocking synthesis of this vitamin in many people. Part of the reason for the FNB’s ultra-conservative recommendation may be found in the approach they took:
In sum, with the exception of measures related to bone health, the potential indications examined are currently not supported by evidence that could be judged either convincing or adequate in terms of cause and effect, or informative regarding dose-response relationships for determining nutrient requirements.
Other than bone density, they really didn’t consider any of the other benefits researchers have found, for two reasons. The first is that studies showing a beneficial effect of the nutrient don’t provide enough evidence that the vitamin is the reason for improvement. While that is debatable, I think the second reason is the most important: studies that do show a benefit do not provide a “dose-response relationship for determining nutrient requirements”. What does that mean? It means that the studies did not provide an easy way for the committee to develop new standards for how much vitamin D you need.
Public policy is often too careful, conservative to a fault, and lags years behind the state of the art.
Disturbingly, this FNB committee focused on bone health, just like they did 14 years ago. They ignored the thousands of studies from the last ten years that showed higher doses of vitamin D helps: heart health, brain health, breast health, prostate health, pancreatic health, muscle health, nerve health, eye health, immune health, colon health, liver health, mood health, skin health, and especially fetal health.
The committee’s findings are more understandable when you realize they are looking only at bone health, and discarding the emerging research showing benefits for an array of other conditions.
Grassroots Health, a public health organization with a large panel of scientists from prestigious universities and hospitals, provided space for several of their colleagues to comment on the report. Dr. Robert P.Heaney, MD, John A Creighton University Professor and Professor of Medicine at Creighton University, said:
There is an impressive body of scientific evidence supporting levels higher than the IOM panel is currently recommending, and for reasons that are not entirely clear, the panel has discounted that evidence. The public needs to know that that evidence exists so that they can make up their own minds. It’s helpful in making those decisions, to know that intakes higher than the IOM [FNB] recommends are safe. For me, that makes the decision easy. Even if the evidence for a higher intake were uncertain (and I don’t believe it is), intakes 2-5 times the IOM recommendations would carry a good chance for benefit at essentially no cost and no risk.
The committee provided their recommendation for a “safe upper limit” of supplementation at 4,000 IU for most people. This recommendation is a low risk proposal, intended for the general public, and most people think it may be due to the prospect of vitamin D toxicity. As a “fat soluble vitamin”, vitamin D is one that can build up and present the ultimate “too much of a good thing.” Yet the same report indicates vitamin D toxicity does not occur in studies except in those supplementing at 50,000 IU and above.
The committee had to deal with a variety of studies showing different “bad effects” for different groups, with black and Asian women differing from white women in increased bone fractures with higher levels of vitamin D (due to the way the vitamin and calcium interact in the body), higher and lower cardio-vascular disease rates in men, etc.
The gold standard of vitamin D supplementation is to test the blood serum levels to dial in the optimum, at least 40 – 60 ng/ml, according to Grassroots Health. They point out that in people taking just 1,000 IU a day, serum levels ranged in people from 15 ng/ml to 85 ng/ml, a wide range that highlights the problem in establishing an RDA (or even an upper limit that is safe for everyone).
How do you get tested? There are some on-line sources for vitamin D testing, taking a simple pin prick to elicit a drop of blood onto a test blotter that you mail in; these are legal in many states. You can also ask your doctor, although your insurance may not cover “voluntary” tests.
For those in the US who cannot convince their family doctor to test for vitamin D levels, Grassroots Health is conducting a 5 year study and preforms the necessary tests every six months. The cost is a recurring $60 per test, and is legal in every state except for New York. See this page for details.