1. How much vitamin D should I take?
Answer:
Before I answer, I have a few questions for you. Where do you live
(latitude)? How much do you weigh? What skin type do you have?
How much do you go into the sun? How much do you get in your diet?
How much do you get in supplements? What is your 25-hydroxy-vitamin
D level? During what season-of-the-year was it obtained?
You see, the answer is different for everyone. The question also
assumes we know the ideal vitamin D blood level. We don't know for
sure; around 50ng/ml is the best current guess.
However, an easy answer is: 2,000 units a day. The government says
2,000 units of vitamin D a day is safe for all adults to take
without a doctor's supervision. Life Extension Foundation sells an
inexpensive pharmaceutical grade of vitamin D. Two-hundred and
fifty of the 1,000 unit capsules cost about ten bucks. Your local
health food store should also carry 1,000 unit capsules. Just be
sure they don't contain any vitamin A. Beta-carotene is OK but
preformed retinols (vitamin A) interfere with vitamin D's function.
I do not advise cod liver oil; if you just have to take it, don't
take more than a teaspoon per day. Get your omega-3s from
molecularly distilled fish body oils (Trader Joe's) or by eating
wild salmon or sardines; get your vitamin D by taking vitamin D or
by going into the sun, or by combining both.
J Nutr. 1999 Dec;129(12):2246-50.
J Bone Miner Res. 2001 Oct;16(10):1899-905.
J Nutr. 2005 Jul;135(7):1647-52.
Remember Professor Robert Heaney's recent warning: two thousand
units a day will only get about 80% of Americans to a vitamin D
level of 35 ng/ml or higher. The 20% still lower than that are
almost all African American or old or obese. 2,000 units a day will
not be enough for some people.
J Steroid Biochem Mol Biol. 2005 Oct;97(1-2):13-9.
For now, if you take more than 2,000 units a day, you should do so
either because you are under the care of a knowledgeable health care
practitioner (good luck finding one), or because you know what you
are doing. I personally take no vitamin D in the late spring,
summer, or early fall because I frequently go into the sun. I take
5,000 units a day in the winter but I know what my vitamin D level
is because I get it checked several times a year. If I had cancer
or heart disease or Alzheimer's disease or multiple sclerosis or a
hundred other common diseases, I might take more than 5,000 units a
day but I'd check my calcium and vitamin D levels even more often.
I'd also follow my doctors advice about standard medical treatment.
Keep in mind that if you use a sunlamp or a tanning parlor once a
week during the winter, you don't have to worry about blood tests
because your body will maintain adequate vitamin D blood levels.
Just don't get burned.
Also, remember to take calcium tablets if you don't get adequate
amounts of calcium in your diet and most people don't. Trader Joe's
sells a good Calcium/Magnesium/Zinc combination product for next to
nothing.
2. What blood test should I have?
Answer:
The only blood test that can determine vitamin D adequacy is a
25-hydroxy-vitamin D. Whenever I say vitamin D level, I'm talking
about a 25-hydroxy-vitamin D. Ask your doctor to order a
25-hydroxy-vitamin D blood test.
Unfortunately, many doctors order an activated vitamin D level,
thinking it better to measure the most active form of vitamin D. It
is not. Activated vitamin D, also known as 1, 25-di-hydroxy-vitamin
D or calcitriol, should never be obtained to determine vitamin D
sufficiency. Calcitriol is often elevated in vitamin D deficiency.
You cannot tell anything about your vitamin D nutrition by measuring
a calcitriol level. If your doctor insists on ordering a calcitriol
level to determine your vitamin D nutrition, find another doctor.
(However, serious problems exist with the technology used by some
laboratories to measure vitamin D levels. Different labs will
report different results when given the exact same specimen of
blood. Furthermore, the same lab often reports significantly
different numbers when sent the same specimen of blood at different
times. In general, low numbers are more reliable than high numbers
because interfering substances can easily give falsely elevated
results. Prominent scientists have issued urgent calls for
standardization. Dr. Graham Carter, one of my personal heroes, has
dedicated his life to obtaining standardized, and accurate, vitamin
D levels. His outfit in London is DEQAS or Vitamin D External
Quality Assessment Scheme. Call your reference lab, such as Quest
Diagnostics (800-222-0446), and insist they participate in DEQAS.
DEQAS's phone in England is +44 (0)20 8383 3645.)
J Clin Endocrinol Metab. 2004 Jul;89(7):3152-7.
J Clin Endocrinol Metab. 2004 Jul;89(7):3149-51.
If you take ergocalciferol, or vegetarian vitamin D, be warned.
Ergocalciferol is not vitamin D, but a vitamin D-like patent drug
whose patent has expired. It does not normally occur in the human
body and is probably a weak agonist at the receptor site, meaning it
may actually partially block vitamin D actions. Ergocalciferol is
the villain in most of the reported cases of toxicity in the world's
literature. All bets are off in terms of measuring blood levels if
you take ergocalciferol. Some of the labs can pick it up and some
can't. Don't take ergocalciferol; it is not vitamin D.
If your doctor prescribes 50,000 units of ergocalciferol (Drisdol)
once or twice a week, obtain a bottle of 50,000 unit capsules of
cholecalciferol from Bio-Tech Pharmacal Inc. of Fayetteville,
Arkansas, and take them instead. Take one or two per week until
your level is around 50 ng/ml. Then stop taking them and begin
maintenance therapy at a much lower dose. You could also take one
5,000 unit capsule every day (also available from Bio-Tech
Pharmacal) until your vitamin D level is around 50 ng/ml. Then take
enough by mouth during the cold months (and go into the sun during
the warm months) to keep your 25(OH)D level around 50 ng/ml. (Keep
in mind that labs inside the USA report usually results in ngs/ml;
labs outside the USA use nmols/L. One ng/ml is equal to 2.56
nmol/L. So 50 ng/ml is about 125 nmol/L.)
Take enough real vitamin D (cholecalciferol) to maintain your level
around 50 ng/ml, year around. A 25(OH)D level is the best, and
only, way you have of knowing if you are taking enough. However, do
not be satisfied with a 50 ng/ml level unless you know how you are
getting enough vitamin D to explain the level (i.e., you go into the
sun or take supplements). If your level is 50 ng/ml and you don't
take supplements, don't go into the sun, don't use a sun booth, or a
UVB lamp, then the level is probably bogus. Repeat the level.
In general, keep your vitamin D level in the upper one third of the
lab's reference range, about 50 ng/ml with the most commonly used
test. If you take higher doses, get your calcium checked when you
get your 25(OH)D level, just to be safe. If you want to be sure
that your hospital is sending their samples to an accurate reference
lab, ask the director of the hospital's lab to contact Professor
Bruce Hollis (843) 792-6854 or Professor Reinhold Vieth (416)
586-5920. Both are the world-class authorities in vitamin D
measurement technology.
(Although 1, 25-dihydroxy-vitamin D (calcitriol) should never be
used to diagnose vitamin D deficiency, calcitriol is important in
evaluating one cause of high blood calcium, called vitamin D
hypersensitivity. High blood calcium rarely occurs due to vitamin D
toxicity, but calcium is elevated in people who have vitamin D
hypersensitivity, although their vitamin D level will be normal or
even low. Primary hyperparathyroidism is a common cause of vitamin
D hypersensitivity, as is sarcoidosis and other granulomatous
diseases. It can occasional occur in cancer; about 20% of patients
with non-Hodgkin's lymphoma have vitamin D hypersensitivity. Any
competent endocrinologist can treat vitamin D hypersensitivity.)
3. Why don't you answer all your emails promptly?
Answer:
I do my best. As the circulation of the newsletter grows and the
popularity of the website increases, I am inundated with questions
like, I have prostate cancer, how much vitamin D should I take? My
husband just learned he has lung cancer; I heard some researchers at
Harvard said he should take vitamin D? My doctor just diagnosed me
with multiple sclerosis, what should I do? Would you please email
me a PDF of Professor Heaney's most recent paper? Would you explain
to me the difference between calcidiol and calcitriol? How much
vitamin D do I need to take if I have the flu? I use full-spectrum
light bulbs so I'm getting plenty of vitamin D, aren't I? Is it
true that children with low vitamin D levels are more likely to get
lung infections? Are vitamin D levels associated with stroke? What
is the Vitamin D Council? Why don't I get the newsletter; I
subscribed? How can I be sure you know what you're talking about?
What is your background? Is it true you are a conservative who used
to be a communist? The list goes on.
My answer is that I do my best. During the day I work full-time to
support my family. I write, and attempt to distribute the
newsletter, on the weekends and evenings. If you dont get the
newsletter, your server is either blocking the mailing or stripping
it of its content so you get a blank email. Be sure
[email hidden] is on your allowed list. If you
don't get the newsletters, you can always read them on the website.
I can't provide personal medical advice. I can't email you
copyrighted material. If you have prostate cancer, or lung cancer,
or any cancer, you should take enough vitamin D so you are no longer
vitamin D deficient (2,000 to 5,000 units a day, enough to get your
vitamin D level around 50 ng/ml and keep it there). If you have MS,
the same is true. If I ever got the flu, I'd take one 50,000
capsule of vitamin D as a single dose although you should know that
not one scientific study exists to support such a decision.
Full-spectrum lighting has virtually no UVB so it will not generate
any vitamin D in your skin.
I try to alert you to all the important studies but I miss a few.
For example, a recent study showed children with low vitamin D
levels are eleven times more likely to get lung infections! Another
recent study showed vitamin D deficiency is a major risk factor for
stroke. I spend lots of time learning about vitamin D and I hope I
know what I'm talking about. Readers can answer most of their own
questions by spending time on the Vitamin D Councils website and
reading old copies of the newsletters . You can read about the
Vitamin D Council's organization on the website underabout us. If
you have to, you can learn about my past lives by reading the
eight-page PDF at: Brief Biography.
4. Where does the Vitamin D Council get its funding and what do you
do with all the money?
Answer:
We don't have any funding. We try to save the little money we have.
Unfortunately, the Kettering Family Foundation just turned down our
$100,000 grant request. I hoped they would fund us as they
generously funded me in the late 1980's when I attempted
(unsuccessfully) to reform testing in America's public schools.
Currently we operate on private donations from readers ($563.00 so
far) and a $5,000.00 donation that my wife and I made to the Vitamin
D Council last year. The first thing we will do when we get funding
is to sponsor a yearly seminar on vitamin D geared towards both
health-care-practitioners and interested lay people. We will ask
vitamin D experts from around the country to speak in plain language
about practical aspects of vitamin D nutrition. If you know anyone
who knows anyone with grant money, send him or her along, our
address is at the end of this newsletter. I have no doubt that God
will provide, should we be doing something worthwhile.
5. If humans make 20,000 units of vitamin D after sunbathing for 20
minutes in the summer, why shouldn't I take 20,000 units every day?
Answer:
Because of what we don't know that we don't know. Someone once said
all knowledge comes in three categories: (1) what you know that you
know; (2) what you know that you don't know; and (3), the largest
category, what you don't know that you don't know. I know that I
know how to speak English; I know that I don't know how to speak
French; I don't know that I don't know how to speak a language that
I don't know exists.
We simply don't know the effects of taking 10,000 or 20,000 units a
day for year after year. Although light-skinned humans make about
50,000 of units of vitamin D after getting a sunburn (3 times the
minimal erythemal dose), we also know they make progressively less
and less vitamin D as their skin produces more and more melanin,
thereby tanning. My 16-year-old daughter has noticed that she tans
much faster when she has been taking oral vitamin D. That is, high
blood levels may tell the skin to make more sunblock (melanin).
Undoubtedly, other natural mechanisms exist to prevent toxicity, we
just don't know. We do know that when healthy young men took 50,000
units of vitamin D every day for six weeks, average serum blood
levels increased by 257 ngs/ml. One young man achieved an increase
of 400 ngs/ml after only six weeks. Although the authors found no
evidence of toxicity after this six-week experiment (serum calcium
remained normal), 50,000 units a day will eventually turn your
internal organs into limestone.
N Engl J Med. 1982 Mar 25;306(12):722-5.
Osteoporos Int. 1998;8(3):222-30.
6. Where do you predict all this vitamin D research is heading?
I predict the final Food and Nutrition Board's recommendation (in
about two decades) will be about 3,000 units a day. I predict that
science will eventually show vitamin D deficiency is a major cause
of many of the diseases of civilization. I predict that science
will eventually show that many of these same diseases of
civilization respond favorably to vitamin D treatment. I predict
science will eventually prove vitamin D helps prevent and treat some
infectious diseases, especially viral respiratory infections like
influenza, croup, and the common cold. These are only my attempts
to prophesize the future. Remember, only time can tell the
difference between and prophet and a madman.
7. What can I do to help?
Answer:
We need funding of course, so any donations are appreciated. We
also need someone who is fluent in German and can translate German
medical papers into English. Email me back if you are fluent in
medical German and are willing to help translating papers.
8. Is it true that vitamin D improves sexual performance, hair
growth, and athletic performance?
Answer:
Are you asking if one of the most potent steroid hormones in the
human body could affect sex, hair growth, or athletic performance?
I'll give you a clue. The literature indicates you are right about
one of the three. However, youll have to wait for a future
newsletter to find out which one.
I hope you have a happy and prosperous new year.
John Cannell, MD
The Vitamin D Council
9100 San Gregorio Road
Atascadero, CA 93422
This is a periodic newsletter from the Vitamin D Council, a
non-profit trying to end the epidemic of vitamin D deficiency. If
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"Newb" <[email hidden]> wrote in message
news:[email hidden]...
Quoted message said:I know the best way to get vitamin D is from the sun. But the fact
is
I am a habitual night owl and frequently miss the sunlight/days.