Taking a lesson from the recent failures of vitamins to live up to their much-hyped potential for disease prevention, the Institute of Medicine is calling for caution in Vitamin D use, concluding in a recent report that the prevalence of vitamin D deficiency and the health benefits of high dose vitamin D intake have been largely overestimated.
Scientific evidence indicates that calcium and vitamin D play key roles in bone health. The current evidence, however, does not support other benefits for vitamin D or calcium intake. More targeted research should continue. However, the committee emphasizes that, with a few exceptions, all North Americans are receiving enough calcium and vitamin D. Higher levels have not been shown to confer greater benefits, and in fact, they have been linked to other health problems, challenging the concept that “more is better.”
The group concluded that vitamin D intake of 600 IUs daily is sufficient for almost all adults up to age 70, with 800Iu recommended daily for those age 71 and older.
Re-defining normal vitamin D levels
The IOM has redefined normal vitamin 25 OH Vitamin D levels in adults as 20 ng/dL for the overwhelming majority of the population, with no additional benefit seen to having levels above 30 ng/dL, and potential harm when levels are above 50 ng/dL.
An urgent call for more research
The insitute is calling for urgently needed research to further define what, if any, role vitamin D may play beyond maintenance of bone health in normal individuals. Until then, caution is advised.
My take
As a clinician, I find the IOM report reassuring and helpful, since until now it seems as if everyone I screen has been vitamin D deficient, and I have been truly wondering how this could be in a population that is overall healthy, and at least here in NYC, getting some sun exposure every day.
Aiming for levels above 20 ng/dL, I suspect most of my patients will not need to take much more vit D than I am already recommending on a daily basis. I will certainly be backing off on treating those with Vitamin D levels already in the low-to-mid 20’s, which seems to be where most of my patients live.
A group I will still be screening and treating for Vitamin D deficiency are those with bone loss. Some of these individuals are older and have Vitamin D levels significantly below 20 ng/dL, which may be how they ended up with bone loss in the first place. For these individuals, I’ll continue my practice of prescribing short periods of high weekly dose D to get them up into normal ranges, then backing off to standard recommended doses.
It’s always the same. One day your are the hot new vitamin and all the rage. The next, you are vitamin non grata. It’s a cruel world.
I am waiting for the reports that come out with fiber being a cause for concern so that I can just eat meat and potatoes like my ancestors before me…They all lived a pretty good long life, but most were pretty pickled in alcohol, so maybe there was a peservation effect there. Who knows!
hi.
i love your blog and am almost always on the same page with you and your thoughts.
however, i do think the jury is still out on the vitamin d issue.
the report seems to ignore the role that vitamim d plays in facilitating gene expression via an autocrine mechanism. there are vitamin d receptors on breast, brain, prostate, colon, immune and other cells. some of these cells convert circulating (25-oh)vitamin d into the usable form (1,25-oh) at the cellular level and function to regulate cell proliferation, differentiation, and apotosis (for all you non-nerdy, non-medical types: this means healthy destruction :-). this is what accounts for all the “miracle” functions of vitamin d. the best explanation of this that i know of was written by robert heaney from creighton and published in the clinical journal of the am soc of nephrology in 2008 (clin j am soc nephrol 3:1535-1541, 2008.)
i’m puzzled that michael hollis (who wrote a review article for the new england journal of medicine 2007;375:266-81),roland veith, robert heaney, bruce hollis, and even lenore buckley (the sole nay-sayer in this group) were not included on the panel, as they are, to the best of my knowledge, some of the most informed on this subject. i don’t pretend to be an expert on this, but i didn’t recognize one name of those who were on the panel that made these most recent recommendations. i also am puzzled that the group allows that doses up to 4000 iu/d are not likely to cause toxicity. for most people, that dose over a relatively short time would almost certainly boost the serum level way far above the 20 ng/dL that the group deems acceptable. i suspect this may have been a concession to panel members who disagreed with the main recommendations.
i think we’ll be hearing more on this subject.
Schrugglin’
Speaking of which, have you heard of the potato diet guy?
http://www.telegraph.co.uk/news/worldnews/northamerica/usa/8172056/American-loses-over-a-stone-on-potato-diet.html
Catherine –
You may be right, but I think the panel was looking for actual evidence that these mechanisms actually impact disease, and at this point we don’t have robust evidence for more than skeletal health.
That said, I rarely see a patient get their D levels much above 30 ng/Dl even with the 50,000 IU dose I prescribe (though I only rx it for 12 weeks at most, and then transition them to 1000 IU daily). I think you really need to take high doses daily for a prolonged period to get into trouble, and I would not be terribly concerned to see someone taking 1000 mg daily.
But you would be surprised how much some folks are taking mega doses daily without any good data yet to support it. I think if this report puts the brakes on this kind of use, it is a good thing.
Thanks for your thoughtful comments.
Peggy
PROFESSOR Frank Garland, and his brother, Cedric, recommend […] taking 50,000 units of vitamin D per week for eight to twelve weeks followed by maintenance on 1,000 to 2,000 units a day”.
ACCORDING Cedric F. Garland, Dr. P.H., FACE, Department of Family and Preventive Medicine and Moores Cancer Center of the University of California, San Diego (UCSD), “It is projected that raising the minimum year-around serum 25(OH)D level to 40-60 ng/ml (100-150 nmol/L) would prevent approximately 58,000 new cases of breast cancer and 49,000 new cases of colorectal cancer each year, and three quarters of deaths from these diseases, in the US and Canada.”
Plasma vitamin D and mortality in older men: a community-based prospective cohort study.
“There was a U-shaped association between vitamin D concentrations and total mortality. An approximately 50% higher total mortality rate was observed among men in the lowest 10% (98 nmol/L [or 39 ng/ml]) of plasma 25(OH)D concentrations compared with intermediate concentrations. Both high and low concentrations of plasma 25(OH)D are associated with elevated risks of overall and cancer mortality.
Dr. Frank C. Garland, 1950-2010
“Tuesday, August 17 at UCSD Thornton Hospital after contending with a nearly year-long illness.“
“African Americans … are more likely to be vitamin D deficient due to their darker skin pigmentation’s ability to block the sun’s rays”
It is not true that melanin blocks the wavelengths which synthesize vitamin D . The value of melanin as a sunscreen (2010).
“epidermal melanin is not a neutral density filter providing no or minimal protection for the induction of erythema at 295 and 315 nm and some protection at 305 and 365 nm”
It does block 305nm but around that wavelength is the most damaging A UVB Wavelength Dependency for Local Suppression of Recall Immunity in Humans Demonstrates a Peak at 300 nm. also see Erythema curve. Note the relative danger curve ( yellow) peaks at around 305nm
T the blocking of a limited spectra of vitamin D synthesizing UVB doesn’t matter the other wavelengths get through. Blood vitamin D levels in relation to genetic estimation of African ancestry “found novel evidence that the level of African ancestry [rather than skin pigmentation] may play a role in clinical vitamin D status”.
There is a negative feedback system; evolution has has got vitamin D levels just right
Klotho protein deficiency and aging.
“α-Klotho protein is shown to function in the negative feedback regulation of vitamin D3 synthesis These observations indicated that abnormal vitamin D3 metabolism is the main cause of aging phenotypes.″
Klotho was named after one of the Moirae or fates, supplementing vitamin D is indeed a fateful step.
Many people of tropical ancestry have a optimum homeostasis of vitamin D which is below the new IoM levels, but if they’re wise they’ll not take supplements
Sorry I make a lot o’ mistakes. Here is the link and correct text.
Plasma vitamin D and mortality in older men: a community-based prospective cohort study
“There was a U-shaped association between vitamin D concentrations and total mortality. An approximately 50% higher total mortality rate was observed among men in the lowest 10% (98 nmol/L [or 39 ng/ml]) of plasma 25(OH)D concentrations compared with intermediate concentrations. Both high and low concentrations of plasma 25(OH)D are associated with elevated risks of overall and cancer mortality.
39ng/ml = 50% higher total mortality rate Yikes.
Catherine Meyer, FYI
Rienhold Veith’s wife owns a vitamin D supplement company. Heaney is also affiliated ‘Heaney reported in 2006 that he had a “financial relationship with SmithKlineGlaxo” — a company which directly produces vitamin D.’ Here
I did it again, ok here is the correct text
“: During follow-up (median: 12.7 y), 584 (49%) participants died. There was a U-shaped association between vitamin D concentrations and total mortality. An approximately 50% higher total mortality rate was observed among men in the lowest 10% (98 nmol/L)[39ng/ml ] of plasma 25(OH)D concentrations compared with intermediate concentrations. Cancer mortality was also higher at low plasma concentrations (multivariable-adjusted HR: 2.20; 95% CI: 1.44, 3.38) and at high concentrations (HR: 2.64; 95% CI: 1.46, 4.78). For cardiovascular death, only low (HR: 1.89; 95% CI: 1.21, 2.96) but not high (HR: 1.33; 95% CI: 0.69, 2.54) concentrations indicated higher risk.
Conclusions: Both high and low concentrations of plasma 25(OH)D are associated with elevated risks of overall and cancer mortality”
I see a lot of deficiency, even by the IOM’s standards–last week an old lady with osteoporosis whose level was 8.6, thank you very much. Like you, I will continue to treat to at least 30.
So relieved to see a report like this.
I take prescription vitamin D in connection with hypocalcemia. There have been times I’ve gotten cut-off and/or deleted for trying to express that vitamin D supplementation can be toxic and is merely the vitamin du jour that gets way over-hyped. Over-hyped especially amongst the ‘I was once a reputable doctor but lost my privileges and now diagnose and prescribe according what I’m able to make money off of’ gang.
Thank you for this entry.
I’m with Catherine. The NEJM review article in 2007 took a bit of a different perspective than what the IOM article states. I moved to a much higher latitude in 2004 and get less sun exposure due to weather and angle of the sun. I’ll continue to take my 2000 IU of Vit D a few times a week for now. Just about every patient I’ve seen has had either deficient or low normal levels in my area.
Catherine- your dose is probably not too far off from the recommendations. I’d you are taking 2000 iu 2 3 times a week that is close to 800-1000 iu a day. Thanks for your comment
The Vitamin D level is less in the geographical areas that receive very little light from the sun. Other diseases which are closely related to Vitamin D deficiency are osteomalacia, osteoporosis and hyperparathyroidism. There can even be many bone fractures in people who are above 50 years due to the demineralization from the bones. The Journal from the American College of Nutrition has released recent reports which has showed that aging does not influence the absorption or the metabolism of Vitamin D.
Hi Dr. P,
I have just discovered TBTAM and absolutely love what you’re doing here. I am also very glad you shared this info on Vitamin D with us.
“…you would be surprised how much some folks are taking mega doses daily without any good data yet to support it..”
I for one would NOT be surprised at all. The sale of vitamins and supplements make up a $23.7 billion industry in North America (that’s ‘billion’ with a ‘B’) that is largely unregulated. As long as manufacturers do not claim on their packaging or advertising that their products can cure disease, they can pretty well make whatever statements they like.
As a heart attack survivor who now takes a fistfull of cardiac meds every morning, I’m stunned by long lists of the supplements being flogged to my fellow heart patients (often by people with the letters M.D. after their names on a number of high-profile retail websites selling these miracle products).
Meanwhile, docs who would never prescribe a heart drug without looking into published peer-reviewed studies on the safety and efficacy of that drug will waltz into the local vitamin shop to load up on who-knows-what with little guidance other than from the friendly clerk on duty.
Personally, I like to see outcomes! I like science-based research. I like bona fide research from independent sources who do not stand to gain financially should I choose to believe their claims.
Thanks again – I plan to share this Institute of Medicine news with my HEART SISTERS readers at http://www.myheartsisters.org
I had to add a Doctor to the list of blogs i follow! love your blog, very informative!