Vitamin D Consenus

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Re: Vitamin D Consenus

Postby JeffN » Wed Apr 27, 2011 6:52 am

Chimichanga wrote:
JeffN wrote:
Wendy Jane wrote:VeggieSue:

Vitamin D Is fat soluble and is stored in the body and so does not have to be taken every day. In fact, in some instances, it is given monthly and even quarterly.

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Do you know how long can it be stored? I have read that getting D through Sun exposure, anything in excess gets destroyed. So if that's the case, building up reservoirs in summer months so you can naturally ride through the winter months in northern climate without supplementation doesn't seem feasible?
I'm not sure above what levels it gets destroyed. For e.g. can you build your levels upto 60-70 ng/ml or even higher at the end of the summer so by the end of winter you deplete it down to say 20 and then charge the battery again. It will be nice if you are able to do this naturally. Build the enough capacity in summer months and ride through winter months without hitting the deficiency levels.

Studies have shown that doses given 4x, 2x and even 1x a year can be effective in maintaining adequate levels throughout the year

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Re: Vitamin D Consenus

Postby Acura » Wed Apr 27, 2011 8:10 am

JeffN wrote:Studies have shown that doses given 4x, 2x and even 1x a year can be effective in maintaining adequate levels throughout the year

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by doses, did you mean to say supplementation or sun light exposure? I'm sorry I didn't get what you meant to say. 4X, 2X of what? and for how long?
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Re: Vitamin D Consenus

Postby JeffN » Wed Apr 27, 2011 8:22 am

It is actually covered in the IOM report.

Yes, studies show that the body can store vitamin D quite effectively from either sun or supplement over time & maintain adequate levels.

There is no one simple answer as there are too many individual variables that go into the equation.

But the individual solution is simple...

Pick a plan, implement it, retest, adjust accordingly.

No two people will ever respond identically.


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Re: Vitamin D Consenus

Postby JeffN » Wed May 04, 2011 6:45 am

The Vitamin D Dilemma:
How much is too much? What you should know about getting tested.
Last reviewed: May 2011 ... /index.htm

Vitamin D is hot—and not just because it comes from the sun. Once prescribed only to prevent or treat outright vitamin D deficiency, rickets, and osteoporosis, doctors have increasingly recommended vitamin D supplements to treat or try to prevent a lengthy list of ills, including autism, certain cancers, diabetes, heart disease, multiple sclerosis, respiratory infections, and cognitive decline in seniors.

Prompted by news reports of vitamin D's benefits and a perception that they don't have enough of it, an increasing number of consumers have been asking doctors to test their vitamin D levels. As a result, sales of vitamin D have skyrocketed to $425 million in 2009 from just $40 million in 2001, according to the Nutrition Business Journal.

But is vitamin D worth the hype? A recent report by the Institute of Medicine found that the news media and medical profession overreacted to the cascade of studies in the last decade associating low levels of vitamin D with numerous ailments. The institute's November 2010 report, which examined more than 1,000 studies and other reports, concluded that vitamin D was essential for bone growth and maintenance but that the evidence of its benefits beyond that was inconclusive.

Since most cells in the body have receptors for vitamin D, its potential involvement in other diseases, such as cancer, is a tantalizing area of research but one that requires more in-depth, large-scale studies. "We don't understand the mechanism for how it might prevent these diseases, or how much is needed," says Frank Greer, M.D., a professor of pediatrics at the University of Wisconsin.

Most of us aren't deficient

Much of the evidence for vitamin D comes from population studies, which have suggested a positive relation between high blood levels of the vitamin and a reduced risk of disease. But they haven't proved a cause and effect. Since vitamin D can be created by exposure to sunlight and is usually higher in people who are thinner, it could be that people who have high levels of the nutrient tend to exercise more or have healthier weights.

And there is confusion over what constitutes vitamin D deficiency. The IOM report challenged the notion of a widespread deficiency of the vitamin or of the mineral calcium. So why do people think they're deficient? One explanation is that most testing laboratories have changed their definition of a "normal" blood level. The lower limit used by many was 20 nanograms per milliliter; now anything under 30 ng/ml is considered an insufficient amount.

While some people truly are deficient in vitamin D, the report concluded that the average American is not. Even assuming minimal sun exposure, the panel found that people are probably consuming adequate amounts of both vitamin D and calcium because they take multivitamins and eat food that has been fortified with those nutrients.

The report's recommendations—that children and most adults get 600 international units of vitamin D a day, and people older than 70 get 800 IU—were more than the targets set 14 years ago (200 IU a day for adults ages 19 to 50, 400 IU for those older than 50, and 600 IU for those older than 70). But they fall far short of the daily intake recommended by some experts—up to 3,000 IU a day for people living in areas such as the Northeast.

Failed promises of other supplements

There are good reasons to be cautious before embracing a nutrient's potential until rigorous testing has been done.

JoAnn Manson, M.D., Dr.P.H., a Harvard Medical School professor who is also chief of preventive medicine at Brigham & Women's Hospital in Boston and a member of the IOM committee, points to the failed promise of supplements of vitamins C and E and the nutrient beta carotene, as well as hormone therapy in women. All of them were at one time thought to prevent cancer or heart disease but didn't withstand the scrutiny of clinical trials. Some studies even suggested that they could be harmful at high levels, increasing the risk of lung cancer (among smokers taking beta-carotene pills), and the potential for heart failure, hemorrhagic strokes, and even death for those taking as little as 400 IU of vitamin E a day.

"These all looked beneficial in observational studies," Manson says. "But when subjected to rigorous testing, they were shown not to be of benefit."

Trials for vitamin D are ongoing, including one that Manson is leading involving 20,000 healthy older Americans. The trials will examine whether taking 2,000 IU of vitamin D a day can lower the risk for heart disease, stroke, or certain cancers. "We expect the benefits will outweigh the risks, but we don't know conclusively," she says.
Is vitamin D a special case?

Other experts argue that the IOM's report is overly cautious and that there is no downside to increasing vitamin D levels. "The good news is, they recognized that the recommendations in 1997 were woefully inadequate, and they increased them threefold, which is quite remarkable for any nutrient," says Michael Holick, Ph.D., M.D., a professor of medicine, physiology, and biophysics at the Boston University School of Medicine and the author of "The Vitamin D Solution" (Hudson Street Press, 2010). "But they didn't go far enough." He recommends that his patients try to achieve vitamin D blood levels of 40 to 60 ng/ml, an amount that typically requires a total of 3,000 IU a day.

The risks

But Consumer Reports Health doesn't agree with that advice for a number of reasons. The IOM report set the upper limit for vitamin D at 4,000 IU for those 9 and older, after which the risk for harm begins to increase. At very high levels—above 10,000 IU a day—there's a risk of kidney and tissue damage.

According to the IOM, a vitamin D blood level above 50 ng/ml should raise concerns about potential adverse effects, which some evidence suggests could include raising the risk for other diseases, such as pancreatic cancer.

And with many proponents of vitamin D arguing for elevating levels into the 40-to-60 ng/ml range for the general population, some experts emphasize the need to be more vigilant.

"People tend to think that if one pill might be good, then maybe a handful would be better," says Tim Byers, M.D., M.P.H., a cancer epidemiologist and associate dean of the Colorado School of Public Health in Denver. "But our experience with this teaches us that caution is needed when taking large doses of supplements. Sometimes we don't discover the harms of supplements until we've accumulated a large enough number of subjects and studies."

For African-Americans, taking vitamin D supplements could even be counterproductive. Last year a study by the Wake Forest University School of Medicine involving 340 African-Americans with type 2 diabetes found that those with the highest vitamin D levels (few of whom were taking calcium or vitamin D supplements) were more likely to have calcified plaque in their major arteries, a predictor of heart attack and stroke.

Barry I. Freedman, M.D., the study's lead author and chief of the section on nephrology there, says that this was the opposite of what occurred in white patients, indicating that the accepted "normal" range of vitamin D might differ among races. He points out that African-Americans have markedly lower rates of osteoporosis and have less calcium deposited in their large arteries compared with whites, despite their lower vitamin D levels.

"We need to determine whether we should be targeting the same vitamin D level in blacks as whites, and better understand the cardiovascular effects of supplementing vitamin D in African-Americans," he says.

Should you be tested?

Our medical consultants say that the evidence suggests that screening as part of a routine regular exam is not yet justified. Instead, it should generally be limited to people who have some objective evidence or reason that they might be vitamin D deficient, such as having markedly weak bones, celiac disease, or other ailments that impair the body's ability to absorb the vitamin from food.

It's less clear whether testing makes sense for people who are at slightly increased risk of low levels because they are overweight, don't get much sun exposure, or eat little vitamin-D rich foods. If they choose testing, they should know that the benefits are less certain for them and that insurance will be less likely to cover the cost, which can range from $40 to almost $300.

What you should know about testing

For adequate bone health, your blood level of vitamin D should be at least 20 ng/ml, a level that would protect at least 97.5 percent of the population against adverse skeletal effects, such as fractures, and ensure healthy bones. Inadequate intakes are diagnosed when levels dip well below 20.

"Doctors are using what clinical labs define as deficient," notes Patsy Brannon, Ph.D., R.D., a professor of nutritional sciences at Cornell University and a member of the IOM panel. "We have people getting lab values back at 29, being diagnosed as insufficient, and being given extremely high doses for fairly long periods of time. You could easily wind up with blood levels approaching 50 ng/ml."

Adding to the challenge of interpreting your results are these factors:

* Vitamin D levels change with the seasons, exposure to sunlight, and dietary intake.

* There is no standardization of vitamin D tests, which means results can differ from one lab to another.

If you decide to be tested, ask whether it will be done in-house or sent to a reference lab, where the volume of tests can be much higher and the accuracy probably better. "Tests like vitamin D are mostly manual and are prone to shifts and bias, which are only observed if one performs at least more than 50 a day," says Ravinder Singh, Ph.D., co-director of the endocrine lab at the Mayo Clinic.

If the results of your test are abnormal or unexpected, you should be retested. If you are found to be deficient, your doctor will probably recommend an oral dose of 50,000 IU of vitamin D once a week for 8 to 12 weeks. After that, maintenance might require 400 to 800 IU depending on your diet. In general, for every 100 IU of vitamin D you take in, there is an increase of roughly 1 ng/ml in the blood level of vitamin D.

Bottom line

Advice can change as studies are completed. "The intakes are not set in stone," says Clifford Rosen, M.D., of the Maine Medical Center Research Institute in Scarborough and a member of the IOM Committee. "If you want a kind of insurance policy in case we find a positive effect later, supplementation is not harmful at low doses."

Until research confirms the benefit of higher doses, stick with the IOM's recommendation: 600 IU for adults up to age 70 and 800 IU for those older than 70. Look for a vitamin D product with the "USP Verified" mark, which means it meets standards of quality, purity, and potency set by the nonprofit U.S. Pharmacopeia. For better absorption of the vitamin, take it with a meal containing some fat. Good food sources of vitamin D include cod-liver oil, cooked button mushrooms, eggs, fortified milk and soy products, mackerel, sardines, and wild Alaskan or sockeye salmon.

If you get some midday sun exposure during the warmer months and regularly consume vitamin D-rich foods, you probably don't need supplements. People who are middle-aged or otherwise at risk of vitamin D deficiency, including those who are overweight or have darker skin, might need supplements. Even then, the amount in most multivitamins is probably enough.
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Re: Vitamin D Consenus

Postby funcrunch » Wed May 04, 2011 1:32 pm

Good food sources of vitamin D include cod-liver oil, cooked button mushrooms, eggs, fortified milk and soy products, mackerel, sardines, and wild Alaskan or sockeye salmon.

I was not aware that eggs and button mushrooms contained naturally-occurring vitamin D - is this true? I don't eat these foods anyway, but am curious...
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Re: Vitamin D Consenus

Postby JeffN » Wed May 04, 2011 2:24 pm

This is from a document I put together recently. I am not recommending animal products but they are listed for comparison sake.

Vitamin D Sources

Naturally Occurring Foods Sources

Vitamin D Occurs Naturally In The Following Foods

Serving Size Amount* Type Comments
Salmon (Sockeye)- 3.5 oz- 900 IU- D3
Maitake Mushrooms- 1 Cup Chopped - 800 IU- D2
Pink Salmon, Canned- 3.5 oz- 500 IU- D3
Mackerel 3.5 oz -450 IU -D3
Sardines, (Canned in water)- 3.5 oz -200 IU- D3
Tuna (canned in water) -3.5 oz- 150 IU- D3
Shiitake Mushrooms- 1 Cup Chopped - 45 IU - D2
Monterey Mushrooms** -3 oz -400 IU -D2

*All numbers are averages based on analysis by the USDA SR 23

**Monterey mushrooms come in many varieties and they produce Vitamin D from exposure to sunlight rays during their growth. They are available in local grocery stores throughout the USA. Check their website to find a local distributor.

Eggs are actually a very poor source as 1 medium egg has only 22 IU

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Re: Vitamin D Consenus

Postby elgaeb051 » Tue Jan 17, 2012 6:09 pm


I find this thread so full of useful information and more up-to-date and/or complementary to the hot-topics you post under Vitamin D in the stickey.

Would you add it to your
"Greetings & Hot Topics:(Please Read Before U Post)" under "Vitamin D"?

Many thanks for the informative posts and information you continue to share.

- E
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Re: Vitamin D Consenus

Postby shell1226 » Thu Jan 19, 2012 6:40 am

Thank you so much for sharing all of this information with us. It is invaluable.

I happen to fall into the category of people that need to supplement Vitamin D as well as others, as I had gastric bypass 5 years ago.

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Re: Vitamin D Consenus

Postby JeffN » Wed Feb 29, 2012 4:36 pm

Increasing requests for vitamin D measurement: costly, confusing, and without credibility

The Lancet Volume 379, Issue 9811, 14-20 January 2012, Pages 95-96. Naveed Sattar, Paul Welsh, Maurizio Panarelli, Nita G Forouhi

“Sunbathing boosts men's sex drives” proclaimed newspaper reports. [1] and [2] This headline was extrapolated from a cross-sectional study showing that serum 25-hydroxyvitamin D (25OHD) concentrations -- a biochemical measure of vitamin D status -- correlate to circulating testosterone concentrations in men referred for angiography, but neither sun exposure nor sex drive was directly assessed.3 This anecdote epitomises what has become a bandwagon of vitamin-D-related epidemiological research fuelling easily accessible headlines in lay media. Such frequent and prominent headlines have cast vitamin D in the role of a putative miracle cure that can prevent and treat a burgeoning list of chronic disorders such as cardiovascular disease, diabetes, and cancer.

This media coverage has caused a massive rise in demand for measurement of blood concentrations of 25OHD from the public and physicians. Glasgow Royal Infirmary -- the main provider of 25OHD tests in Scotland -- has seen a rise in vitamin D test requests from 18?682 in 2008, to 37?830 in 2010, which has resulted in a longstanding backlog of 2000 tests. Similarly, a hospital in London, UK, had a sixfold increase in 25OHD test requests over 4 years, rising from 7537 tests in 2007, to nearly 46?000 in 2010 (personal communication). Similar trends have been noted in other countries -- eg, Canada and the USA. [4] and [5] To match demand, manufacturers (eg, Abbott, Roche, and Siemens) are developing immunoassays (similar to liquid chromatography tandem mass spectrometry gold standard) for clinical use, and promoting them widely in North America, Europe, and elsewhere. A 25OHD test costs the UK National Health Service around ÂŁ20. The economic burden of widespread routine vitamin D testing in the UK and elsewhere is therefore substantial.

But is this skyrocketing of 25OHD test requests and related costs justified? The prevalence of apparent vitamin D inadequacy is high in the UK. [6] and [7] For example, roughly 50% of 45-year-old UK adults (1958 British birth cohort) were vitamin D insufficient during winter months, with the greatest inadequacy recorded in Scotland (average concentration 35 nmol/L).7 A patient in the UK attending a general practitioner in winter is therefore likely to be vitamin D insufficient (serum concentrations <50 nmol/L) or deficient (serum concentrations <25 nmol/L). But how should general practitioners interpret such test results? The key question is: does knowing the result usefully improve clinical practice and patient wellbeing?

To address this issue, whether vitamin D inadequacy has a predisposing relation with health consequences that could be avoided by intervention (eg, supplementation, diet, or sun exposure) needs to be established. Most evidence promoting a role for vitamin D in chronic disease has been extrapolated from epidemiological studies, but these results are often limited by factors such as potential reverse causality and residual confounding -- particularly relevant limitations for vitamin D as a biomarker of health (table). Therefore, any conclusions about causality extrapolated from observational data are premature.10

Table. Potential limitations in making causal inferences from observational epidemiology for vitamin D
Why important for vitamin D?
Confounding and residual confounding
Many risk factors are related to both low
25OHD and poor health outcomes;
statistical models might be incomplete if
such factors are not measured, or
measured imprecisely

Little physical activity (outdoor activity
often related to sunlight exposure);
low socioeconomic status; obesity;
smoking; season
Reverse causality
Sunlight exposure is a major determinant
of circulating-25OHD concentrations; pain
or illness can limit sunlight exposure
through inactivity, and thus disease could
cause inadequacy rather than the reverse

Clinical diagnosis of many disorders (eg,
multiple sclerosis) can be preceded by a
period of preclinical disease when little
time is spent outdoors; acute
infl ammation can drive down circulating
25OHD concentrations so that in acute
illnesses or many hospitalised patients, low
measurements are secondary to an
acute-phase response
Publication and citation bias

Null or negative fi ndings are less likely to be
published, especially when overwhelming
perception is of a positive association; thus,
investigators are less likely to pursue
publication or persist after manuscript
rejection than if results were positive; null
fi ndings that are published are not
frequently cited and result in little media
interest, and therefore perception of the
weight of evidence can be heavily skewed

Marniemi and colleagues’ 2005 report8 of
no association of 25OHD with 130 cases of
myocardial infarction in elderly people has
been cited 33* times in Web of Science; by
contrast, Wang and co-workers’
2008 article9 reporting 25OHD inadequacy
associated with 120 cases of cardiovascular
disease in Framingham off spring has been
cited 409* times
25OHD=serum 25-hydroxyvitamin D. *As of Nov 28, 2011.

The only reliable tests of causality are randomised trials. The effectiveness of vitamin D supplementation in rickets and osteomalacia has been proven. Vitamin D supplementation in appropriate doses with concomitant calcium supplements might reduce the risk of fractures in elderly people at risk of osteoporosis.11 However, the need to measure circulating vitamin D in people with osteoporosis (diagnosed on the basis of dual energy x-ray imaging scans) is questionable because treatment is likely to include vitamin D supplements irrespective of the result. Meanwhile, convincing evidence that vitamin D supplements reduce the risk of cardiovascular disease or diabetes, or lower glucose concentrations in patients with diabetes, does not exist.12 Proponents argue that longer trials with higher doses of vitamin D than have been tested heretofore are needed, and we agree. However, until the investigators of such trials report their results, we must remain cautious about the recommendation of widespread supplementation for chronic disease prevention. The reports13 of increased rates of infantile hypercalcaemia in the UK in the 1950s after overenthusiastic food fortification with vitamin D show the importance of caution -- a point re-emphasised in 2011.14

In short, widespread testing of asymptomatic people's vitamin D status is unhelpful. Economic constrictions are a concern for health-care providers worldwide. Until the results of large randomised trials are reported, we urge all clinicians to stop and think critically before measuring 25OHD, particularly in conditions not linked to bone disease. Such practice will avoid many unnecessary tests, reduce laboratory backlog, and save a lot of health-service time and money without affecting patients' health.

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Re: Vitamin D Consenus

Postby energy_dad » Tue Mar 20, 2012 8:46 am

Hi Jeff,

I was curious what your thoughts on this were:

"It should be noted that the American Academy of Dermatology urges people not to get vitamin D via sunshine because of the increased risk of cancer (38)"
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Re: Vitamin D Consenus

Postby Julia » Fri Mar 23, 2012 1:34 pm

HI Jeff,

I am into confusion again. I looked into a bit of Dr. Joel Fuhrman's advice and thought a lot of what he said is plausible. How does one ever know how to judge all the info if we are not experts. Dr Fuhrman recommends supplementing with 15mg Zinc, 150 micrograms iodine and 1000 - 2000 IU of D every day.

I know I live in an iodine deficient area. I do buy all my produce organically and some is grown near the ocean. How do I know if it is enough.

I know that Dr Mcdougall and others recommend nothing but B12.I feel rather lost in the contradictory information.

How do two doctors following the same ideas of healthy nutrition, backing everything they say up with research come to such different conclusions on "to supplement or not to supplement?.

Best Julia
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Re: Vitamin D Consenus

Postby JeffN » Fri Mar 23, 2012 1:51 pm

energy_dad wrote:Hi Jeff,

I was curious what your thoughts on this were:

"It should be noted that the American Academy of Dermatology urges people not to get vitamin D via sunshine because of the increased risk of cancer (38)"

Sunshine is a requirement of health.

Inadequate exposure can pose health problems as can excessive exposure.

For many people, sunshine can be more than adequate and if not, still make a significant contribution (as outlined in the consensus statements above).

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Re: Vitamin D Consenus

Postby JeffN » Fri Mar 23, 2012 4:09 pm

Julia wrote: Zinc

on zinc


Julia wrote: iodine

on iodine


viewtopic.php?f=22&t=23557 ... htm#bm18.4

Julia wrote: D

In regard to Vitamin D, please re-read my comments in this thread from the beginning.

Julia wrote:I know I live in an iodine deficient area.

Unless everything you eat is grown 100% locally, you consume food that has been grown around the country and from many parts of the world.

Julia wrote:"to supplement or not to supplement?.

My position on supplements


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Re: Vitamin D Consenus

Postby Julia » Tue Mar 27, 2012 11:18 am

thanks for your response Jeff.

Just a question. How can we know if we absorb enough zinc on a complete vegan diet when the phytates in a lot of the food inhibit the zinc absorption. Would you not consider this a problem to worry about?

Thanks again,

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Re: Vitamin D Consenus

Postby JeffN » Tue Mar 27, 2012 11:25 am

Julia wrote: How can we know if we absorb enough zinc on a complete vegan diet when the phytates in a lot of the food inhibit the zinc absorption. Would you not consider this a problem to worry about?

Depends on your overall diet and lifestyle :)

Zinc recommendations are actually based somewhat on the level of phytates in the diet and as such, there are three levels of recommendations for zinc to account for this issue.

If you read the full zinc discussion and the link to the report on zinc, you can see this is all covered and the varying levels.

If you use the CRON O Meter, you can easily see how well you are doing and if you find the need, you can make any minor adjustments in your diet, with the above chart of zinc density

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