Vitamin D: What is an adequate vitamin D level and how much supplementation is necessary?

[Celebration]

Answer to the question we have all wanted to know--

http://www.ncbi.nlm.nih.gov/pubmed/19945690?itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum&ordinalpos=13

Strong evidence indicates that many or most adults in the United States and Europe would benefit from vitamin D supplements with respect to fracture and fall prevention, and possibly other public health targets, such as cardiovascular health, diabetes and cancer. This review discusses the amount of vitamin D supplementation needed and a desirable 25-hydroxyvitamin D level to be achieved for optimal musculoskeletal health. Vitamin D modulates fracture risk in two ways: by decreasing falls and increasing bone density. Two most recent meta-analyses of double-blind randomised controlled trials came to the conclusion that vitamin D reduces the risk of falls by 19%, the risk of hip fracture by 18% and the risk of any non-vertebral fracture by 20%; however, this benefit was dose dependent. Fall prevention was only observed in a trial of at least 700IU vitamin D per day, and fracture prevention required a received dose (treatment dose*adherence) of more than 400IU vitamin D per day. Anti-fall efficacy started with achieved 25-hydroxyvitamin D levels of at least 60nmoll(-1) (24 ngml(-1)) and anti-fracture efficacy started with achieved 25-hydroxyvitamin D levels of at least 75nmoll(-1) (30ng ml(-1)) and both endpoints improved further with higher achieved 25-hydroxyvitamin D levels. Founded on these evidence-based data derived from the general older population, vitamin D supplementation should be at least 700-1000IU per day and taken with good adherence to cover the needs for both fall and fracture prevention. Ideally, the target range for 25-hydroxyvitamin D should be at least 75nmoll(-1), which may need more than 700-1000IU vitamin D in individuals with severe vitamin D deficiency or those overweight.

[snagglepuss]

1. 16 of the world's leading Vitamin D researchers recommend 2000 IU daily

Grassroots Health's "D-action" panel - 16 of the world's leading researchers on vitamin D recommend 2,000 IU of vitamin D daily and vitamin D blood levels of 100-150 nmol as measured by a vitamin D blood test.

IMPORTANT TO KNOW THAT U.S. Labs normally don't use nmol as a measurement they use ng/L. So the ng/L equivalent of 100-150 nmol is 40-60 ng/L.


Dr. Reinhold Vieth, one of the world's leading Vitamin D researchers, points out that natural vitamin D levels of mammals who live outdoors in sunny climates is higher than that - up to 200 nmol.



http://www.grassrootshealth.net/

[TheMadMonk]

2. Ten minutes a day of sunlight, a bit more in winter or in more northerly climes.

Sun smart, becomes sun stupid when taken to such an extreme that a person requires a Vitamin-D supplement.

[snagglepuss]

3. You are profoundly uninformed. nt

[Mojorabbit]

5. Not true says this Florida girl

who gets plenty of sun and is on prescription strength Vit D as my test came up low even though I was already taking supplemental vit d. Lots of new research out there on the subject. I think the fda will be revising it's minimum dose soon.

[MorningGlow]

6. Sorry, not true

Some people (like me, my mom, and my son) have an absorption problem, even in summer. We all came up severely deficient, and my mother is ALWAYS outside gardening (and she doesn't wear sunscreen). I'm often outside, and one thing I like about my son's school is they boot them outside to play as long as it's not raining.

Sometimes people just need the supplements.

[HysteryDiagnosis]

13. Some people less stupid than others.

http://www.naturalnews.com/003069.html

# It is nearly impossible to get adequate amounts of vitamin D from your diet. Sunlight exposure is the only reliable way to generate vitamin D in your own body.

# A person would have to drink ten tall glasses of vitamin D fortified milk each day just to get minimum levels of vitamin D into their diet.

# The further you live from the equator, the longer exposure you need to the sun in order to generate vitamin D. Canada, the UK and most U.S. states are far from the equator.

# People with dark skin pigmentation may need 20 - 30 times as much exposure to sunlight as fair-skinned people to generate the same amount of vitamin D. That's why prostate cancer is epidemic among black men -- it's a simple, but widespread, sunlight deficiency.

# Sufficient levels of vitamin D are crucial for calcium absorption in your intestines. Without sufficient vitamin D, your body cannot absorb calcium, rendering calcium supplements useless.

# Chronic vitamin D deficiency cannot be reversed overnight: it takes months of vitamin D supplementation and sunlight exposure to rebuild the body's bones and nervous system.

# Even weak sunscreens (SPF=8) block your body's ability to generate vitamin D by 95%. This is how sunscreen products actually cause disease -- by creating a critical vitamin deficiency in the body.

[LeftishBrit]

14. That is an irresponsible article

If an article uncritically endorsed a Pharma product known to increase the risk of cancer, without warning about it, you would rightly say that they were being very irresponsible (e.g. if they recommended HRT without saying that it can increase the risk for breast cancer).

Yet, sunlight exposure is known to increase the risk for skin cancer, especially in white people and this article seems to be discouraging sunscreen use, without warning of the melanoma risk.

[ginnyinWI]

4. my doc said to take 2,000 IU daily.

This is especially important for those of us who live in the North.


p.s. since I've been taking vitamin D my mood has been better too--they say it helps prevent depression.

[MrsCorleone]

7. Just thinking out loud, but I wonder what role an of excess of soy & its derivatives

in our diet play in vitamin D (& calcium) depletion, given that some variant of soy is found in much of our processed foods? Unless one consumed only whole foods and stayed away from soy beans, tofu, etc., I'd guess that folks are taking in a lot more of this stuff than is healthy.

MorningGlow & Mojorabbit's mention of low vitamin D levels despite sun exposure, although anecdotal, is interesting.

Thoughts?

[laughingliberal]

12. Would not likely account for my deficiencies. I gave up soy years ago when I read it depresses the

thyroid.

[tiptoe]

8. In English: Safety, "How much should I take?", MD gen dosage recs, optimal levels (scientific refs)

from: Safety & two MD general recommendations: "How Much Vitamin D Should I Take?"

...
How Much Vitamin D Should I Take?
Again, we don't know. This is a difficult question because it relies on so many personal factors. Everyone's situation is either a lot, or at least a little, different. How much vitamin D you need varies with:

• age
  
• body weight
  
• percent of body fat
  
• latitude
  
• skin coloration
  
• season of the year
  
• use of sunblock
  
• individual variation in sun exposure, and—probably—
  
• how ill you are

As a general rule, old people need more than young people, big people need more than little people, heavier people need more than skinny people, northern people need more than southern people, dark-skinned people need more than fair-skinned people, winter people need more than summer people, sunblock lovers need more than sunblock haters, sun-phobes need more than sun worshipers, and ill people may need more than well people.

Quite a few factors are involved, as you can see. However, don't feel bad, no one understands it. Vitamin D is used by the body—metabolically cleared—both to maintain wellness* and to treat disease.

• If you get an infection, how much vitamin D does your body use up fighting the infection?
• If you have cancer, how much vitamin D does your body use up fighting the cancer?
• If you have heart disease, how much vitamin D does your body use up fighting the heart disease?
• If you are a child with autism, how much vitamin D does your brain need to turn on the genes that autism has turned off?
• If you are an athlete, how much vitamin D does your body use to make you stronger and quicker?

Nobody knows the answer to these questions.
...

– John Cannell, MD  2008/10/01  Am I Vitamin D Deficient?

*(ed: link added — latest recommended optimal serum vitamin D levels, per six experts)

Two MD General Dosage Recommendations

...

Safety

...
Cholecalciferol, Not Ergocalciferol, Is Safe
Although there are documented cases of pharmacological overdoses from ergocalciferol, the only documented case of pharmacological—not industrial—toxicity from cholecalciferol we could find in the literature was intoxication from an over-the-counter supplement called Prolongevity. On closer inspection, it seemed more like an industrial accident, but it was interesting because it gave us some idea of the safety of cholecalciferol. The capsules consumed contained up to 430 times the amount of cholecalciferol contained on the label (2,000 IU). The man had been taking between 156,000–2,604,000 IU of cholecalciferol a day (equivalent to between 390–6,500 of the 400 unit capsules) for two years. He recovered uneventfully after proper diagnosis, treatment with steroids, and sunscreen.

It is true that a few people may have problems with high calcium due to undiagnosed vitamin D hypersensitivity syndromes such as primary hyperparathyroidism, granulomatous disease, or occult cancers, but a blood calcium level, PTH, 25(OH)D, and calcitriol level should help clarify the cause of the hypersensitivity. Although D can be toxic in excess, the same can be said for water.

Therapeutic Index
As a physician, I know that psychotic patients should drink about 8 glasses of water a day. However, many would hurt themselves by regularly drinking 40 glasses a day (called compulsive water intoxication). So you could say that water has a therapeutic index of 5 (40/8).

Heaney's recent research indicates that healthy humans utilize about 4,000 units of vitamin D a day (from all sources). However, 40,000 units a day, over several years, will hurt them. Therefore, vitamin D has a therapeutic index of 10 (40,000/4,000)—twice as safe as water. We are not saying vitamin D is as safe as water, we are saying vitamin D is safe when used in the doses nature uses.

Sun Supplies 10,000 Units Of Vitamin D
The single most important fact anyone needs to know about Vitamin D is how much nature supplies, if we behave naturally, e.g., go into the sun. Humans make at least 10,000 units of vitamin D<3> within 30 minutes of full body exposure to the sun, what is called a minimal erythemal dose. Vitamin D production in the skin occurs within minutes and is already maximized before your skin turns pink.
...

– John Cannell, MD  2009/06/20 The Truth About Vitamin D Toxicity

• The good news is that in the current literatureNO TOXICITY reported BELOW 500nMol/L == 200 ng/mL*That's not to say there might not be a paper tomorrow that comes out at 190 ng/mL or something like that...but the available literature says that you have to be above 200 ng/mL (500nMol/L), before you have to worry about toxicity.
  
• Similarly, there's NO TOXICITY below 30,000 IU/day—for long periods of time, not just single doses.
  
• The paper concluded that the Tolerable Upper Intake Level should be set at 10,000 IU/day. Now, once again, nobody's recommending 10,000, but that's a factor of 3 safety, and — even there — I can't think of many clinical situations which that might be useful, if any.

– Robert P. Heaney, MD  :31:15 What Is A Vitamin D Deficiency?

* six experts' combined ranges of latest recommended optimal serum 25(OH)D levels: 40 to 100 ng/mL

Any benefit of vitamin D needs to be balanced against the risk of toxicity, which is characterized by hypercalcemia. Daily brief, suberythemal exposure of a substantial area of the skin to ultraviolet light, climate allowing, provides adults with a safe, physiologic amount of vitamin D, equivalent to an oral intake of about 10,000 IU vitamin D(3) per day, with the plasma 25-hydroxyvitamin D (25(OH)D) concentration potentially reaching 220 nmol/L (88 ng/mL). The incremental consumption of 40 IU/d of vitamin D(3) raises plasma 25(OH)D by about 1 nmol/L (0.4 ng/mL). High doses of vitamin D may cause hypercalcemia once the 25(OH)D concentration is well above the top of the physiologic range. The physiological buffer for vitamin D safety is the capacity of plasma vitamin D-binding protein to bind the total of circulating 25(OH)D, vitamin D, and 1,25-dihydroxyvitamin D <1,25(OH)2D>. Hypercalcemia occurs when the free concentration is inappropriately high because vitamin D and its other metabolites have displaced 1,25(OH)2D from vitamin D-binding protein. Evidence from clinical trials shows, with a wide margin of confidence, that a prolonged intake of 10,000 IU/d of vitamin D(3) poses no risk of adverse effects for adults, even if this is added to a rather high physiologic background level of vitamin D.

Reinhold Vieth, PhD  Ann Epidemiol 2009;19(7):441-5 Vitamin D & cancer mini-symposium: the risk of additional vitamin D

...
Physicians think vitamin D itself causes calcium aborption. That's why we've had to overcome this idea that Vitamin D can be toxic in the types of doses we're typically using: It doesn't cause an increase in calcium absorption; it doesn't cause hypercalcemia; and it doesn't cause hypercalciuria — in the kinds of doses we're talking about.

– Robert P. Heaney, MD  :17:53 What Is A Vitamin D Deficiency?

...
Our study highlights that 100 000 IU cholecalciferol is a safe, efficient, and cost-effective means to increase calcidiol concentrations in the elderly. From this study we can safely recommend 100 000 IU cholecalciferol dosed every 2 mo in persons with moderate baseline calcidiol concentrations. However, in those persons with baseline calcidiol concentrations < 20 ng/mL, even this large dose will not adequately raise their calcidiol concentrations.

– RP Heaney, MD  Amer J Clin Nutr. 2008 Mar;87(3):688-691. Pharmacokinetics of a single, large dose of cholecalciferol

[tiptoe]

11. "Serum 25(OH)D levels < 80 nmol/L (32ng/ml) are not adequate for any body system. Calcium absorptive

...regulation is suboptimal below 80 nMol/L ( 32 ng/ml)"   @ :36:54 What's A Vitamin D Deficiency?* – Dr. Robert Heaney

@ :16:54 best-estimate of primitive level = 60 ng/mL is "very reasonable"

@ :17:52 A Vitamin D Threshold
32 ng/mL for serum 25(OH)D is a threshold level for optimal calcium absorption
"For calcium absorption you'd say that the minimal daily requirement would be one that produces 80 nMol/L (32 ng/mL) or higher in serum 25(OH)D"

@ :18:40
"I want to stress it is not the Vitamin D or the 25(OH)D which is causing this absorption; it is simply enabling the body's regulation of calcium absorption.
— A crucial distinction: Vitamin D's function is an enabling function, rather than a causative function."

— @19:14 "At this point the body is able to UP-regulate absorption to 50% (or even higher in some people) or DOWN-regulate to 10% or 15%, simply by changing the production of 1,25 D"   (i.e.,  1,25(OH)₂D₃ — active Vitamin D, calcitriol, a secosteroid hormone)

— @ :19:28 "Physiological regulation is no longer limited by Vitamin D availability (at 80 nMoles/Liter)
Range of regulation at various 25(OH)D levels
— "On the other hand, if you're working on the ascending limb of that curve, you still got the ability to regulate, but you can't regulate it as high...so, you don't have the ability to adapt to low calcium intake. And you can down-regulate it as well. So, the body is still in charge, but it's just limited in how high it can go under the circumstances. So, that's the way to think about how Vitamin D is acting with respect to calcium absorption."

— @ :19:59
"Now Physicians think Vitamin D itself causes calcium aborption. That's why we've had to overcome this idea that Vitamin D can be toxic in the types of doses we're typically using: It doesn't cause an increase in calcium absorption; it doesn't cause hypercalcemia, and it doesn't cause hypercalciuria — in the kinds of doses we're talking about."

— @ :20:25
"The evidence to be presented in all the papers that follow points to a requirement for serum 25(OH)D that is above 80nMol/L -- the level required for the maintenance of optimal regulation of calcium absorption -- and perhaps as much as 100-125 nMol/L ( 32ng/mL to 40-50ng/mL )"
...

*Vitamin D Deficiency - Treatment and Diagnosis – UCSD School of Medicine and GrassrootsHealth Seminar Series Programs

 

[tiptoe]

9. Serum 25(OH)D units conversion: 32 ngrams/mL * 2.496 == 80 nMoles/L

...for clarification of the units of measure mentioned in the OP.

[wuvuj]

10. I'll be back.....

http://list.netatlantic.com/t/49795212/75028026/104386/0/


The Great Disappearing Act

We are currently witnessing one of the great mysteries of the natural world. The H1N1 outbreak is rapidly disappearing, despite a wealth of potential victims without antibodies to the virus, and yes, in spite of plummeting Vitamin D levels. In several weeks, the CDC will announce that perhaps one-third of Americans were infected in the last nine months and now have Swine flu antibodies, leaving the majority of the population still susceptible.

But this H1N1 virus is rapidly refusing the invitation to infect the two-third of Americans who are mostly immunological virgins and will soon recede until the next widespread outbreak, which may come this spring or next fall and winter. When H1N1 returns again, I predict it will cause more illness and death than it did this fall despite the fact it will attack a population with more H1N1 specific antibodies. Measles, another virus thought to transmit via respiratory secretions, would never forego the opportunity to infect so many virgins.

Influenzologists have no idea why this Disappearing Act happens. Dr. Edgar Hope-Simpson believed the reason lay in the mode of transmission; the current outbreak is ending despite a wealth of potential victims because the people transmitting the flu are suddenly no longer contagious. I recommend Hope-Simpson’s book:

The Transmission of Epidemic Influenza (The Language of Science).

I also believe that only a small population was transmitting, not all those infected. If these good transmitters – and not all the sick – usually spread the virus, and their transmission period is limited, the epidemic would end shortly after the good transmitters lose their infectivity. Why they lose their infectivity is yet another mystery, but a mystery that fits the epidemiology of influenza.

Cannell JJ, Zasloff M, Garland CF, Scragg R, Giovannucci E. On the epidemiology of influenza. Virol J. 2008 Feb 25;5:29. Review.

Another incredible Disappearing Act, one that usually follows the introduction of a pandemic virus, is the rapid and usually complete replacement of seasonal flu with the pandemic one. It is as if the pandemic virus murders the seasonal flu. We will have to wait to see if that happens worldwide with this pandemic, but in the USA it has already happened. Last week the CDC reported that more than 99% of all influenza viruses identified in the USA were Swine flu. Only 1 of 1,874 influenza A viruses identified last week was seasonal flu. Where did the seasonal flu virus go?

[Mojorabbit]

15. I read an article yesterday I think

from Australia where they were preparing for a third wave. It will be interesting to see what happens next.