Target tissues for Vitamin D--Curr Opin Clin Nutr Metab Care 10:12-19, 2007
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"Since the Human Genome Project, we now know that Vitamin D is responsible for regulating over 10% of our genes. It's not just responsible for skeletal health--but cells throughout the entire body are dependent on Vitamin D in order to work properly.
I'm talking about brain function, nerve function, immune function, skeletal function--all dependent on adequate supplies of Vitamin D--including its important role in preventing 14 types of cancer, heart disease, autoimmune disease, diabetes, inflammation/inflammatory diseases, infection, and osteoporosis."
It's February! By this time of the year if you live in the Northern half of the U.S. most of the vitamin D you've stored from the sunshine is long gone and you're at your lowest level of the year. You haven't made a drop since October. The average American's blood level in the winter is 15-18 ng/mL.
If you read the February 1, 2010 New York Times article, "The Miracle of Vitamin D: Sound Science, or Hype" you might be tempted to dismiss the recent research on Vitamin D. I wouldn't advise it. If you want to wait to get your "sunlight fix" or down your Vitamin D supplements until the gold standard randomized control Vital Study is complete--go for it.
I wouldn't count on its results being conclusive. The study group is too old-women over 65 & men over 60. The dose is the same for everyone which makes no sense when it comes to vitamin D--because everyone has a different base level of vitamin D--and vitamin D doses are weight dependent. Plus, much of the benefit of taking vitamin D occurs years before disease may surface.
In December 2009 I reported on Dr. Bruce Hollis' research on the effects of Vitamin D in pregnancy and breast-feeding. This post is the continuation of my summary of his interview with Joe and Terry Graedon on the People's Pharmacy, November 19, 2009.
For my previous posts on vitamin D, click here:
- Dr. Bruce Hollis' NIH Vitamin D in Pregnancy Study is Now Complete. High Dose Vitamin D (4000 IUs) Significantly Improved Health & Outcomes for Moms and Babies. And Harvard Researchers' Theory of a Vitamin D - Autism Connection
- Everything You Ever Wanted to Know About Vitamin D from the Expert, Dr. Michael Holick. How Much Do We Need? Why Is It So Hard to Get Enough? What About Breast-Fed Babies? Why Is It So Important for Good Health?
- Why is Vitamin D my favorite? Let me count the reasons.
- Caroline Adams Miller's Ten Non-Negotiable Pearls to a Life Well-Lived - Successful Balanced Happy. And the Possible Dementia Vitamin D Connection
He's one of the leading authorities on vitamin D, as well as Professor of Pediatrics, Biochemistry and Molecular Biology, and the Director of Pediatric Nutritional Sciences at the Medical University of South Carolina in Charleston, SC.
If this vitamin is so important, why are so many of us deficient?This potent hormone is made through the skin--we were designed to get it from the sun, not through food or supplements. Most of us spend much of our time indoors, and when we are outside we're covered in clothing and sunscreen. If you live above the 37th parallel (Richmond, VA-St. Louis, MO-Sacramento, CA) you can't make enough vitamin D from the sun for almost 6 months out of the year!
Why are the RDIs (recommended daily intakes) for Vitamin D so low - at 200 or 400 IUs? Why is the normal blood level for Vitamin D set so low, at 31?
According to Hollis, the federal guidelines for vitamin D--set at 200-400 IUs/day are 100% absolutely incorrect! They don't even begin to touch what we need. The 400 IU recommendation was based on the amount needed to prevent rickets--based on no real data--and Hollis believes that for those recommendations to continue today, is medical malpractice. Hollis' own recent safety & outcomes pregnancy study recommends 4000 IUs during pregnancy.
We've known for over 30 years that if you get 15 minutes of sun exposure in a bathing suit between 10 and 2 o'clock, in the middle of the summer, your body will produce 20,000 IUs of vitamin D within 24 hours. The body can make and release huge amounts of vitamin D--and yet national guidelines are still recommending only 400 IUs a day.
According to Hollis, most adults need 2000 IUs or more/day, and he takes 4000 IUs. He monitors his blood levels with the 25-hydroxy vitamin D test, and tries to keep his levels at 50-60 ng/mL.
4000 IUs would replete (maintain at the optimal level) almost all adults unless they were obese or had a high BMI. In obese patients, Hollis has even found that 10,000 IUs was not be enough to adequately raise their blood levels. There really is no rule of thumb for "the right dose" of vitamin D for obese individuals--you just have to monitor the blood levels and make adjustments through trial and error.
Why are doctors now testing for vitamin D levels? If 31 ng/mL is normal, why would I want to go over that level?
The history of the 25-hydroxy-Vitamin D test. Dr. John Haddad of Washington University School of Medicine developed the first test for measuring vitamin D in the blood back in the 1960s. To figure out what a "normal" level of Vitamin D was--a level that prevents rickets--he measured a huge number of people, like office workers, physicians, and people of color. Their average blood level was 27 ng/mL--and to prevent rickets you only needed to be above 10 ng/mL.
Back in the 1970s, it looked like most everyone was "normal" if they were over 10 ng/mL. Today, we know so much more--and rickets is the least of vitamin D deficiency diseases. Fortunately, Haddad also tested lifeguards--and their levels were at 50-100 ng/mL. Dr. Hollis believes that those are the optimum levels for good health--the physiological level one would reach if he were fully sun-exposed.
Studies continue to show that the higher the vitamin D level, the lower the risk of diabetes, heart disease, multiple sclerosis, osteoporosis, infections, breast, prostate, and colon cancers, and rheumatoid arthritis. 31 ng/mL has now become the lowest normal level.
Classification of 25 OH Vitamin D status:
Insufficiency/Moderate Deficiency: < or = 30 ng/mL
Sufficiency/Optimal Levels: 31 to 80 ng/mL
Toxicity: > 100 ng/mL
What have we learned from new research on Vitamin D?
The Human Genome Project has opened our eyes. 10% of our genes are influenced by Vitamin D--and very few of these have to do with the skeleton or bone health. Important processes like cell maintenance, cancer immune function, autoimmune function, infection and inflammation control--to name a few--are all affected by our levels of vitamin D.
Around 2000 research began to surface about the optimal health effects of higher blood levels of vitamin D. In Dr. Hollis' recent pregnancy study he found immune function improved significantly--and infection rates dropped--when vitamin D was supplemented in pregnant women to 4000 IUs. He saw absolutely no adverse effects at this level.
How about some examples of how vitamin D supplementation has helped people in everyday medical practices?
An elderly home-bound population. Dr. S of Getzville, NY is a geriatrician treating home-bound elderly with multiple chronic conditions. "The medical community doesn't understand the physical limitations caused by vitamin D insufficiency. The muscle and bone pain from low vitamin D can be considerable."
Here's just one example of how increasing a patient's level of vitamin D to an "robust level" benefited one of Dr. S's patients. He resolved a patient's debilitating limb pain--which was poorly responsive to narcotics--just by increasing the patients' vitamin D to optimum levels. He has even helped patients who have stopped walking--when they were identified as having very low Vitamin D levels.
To determine the best way to increase his patients' vitamin D levels, he takes into account their current level and their weight, and uses a table (see below) that can be found in Dr. James Dowd's book, The Vitamin D Cure. The table is based on the research of Dr. Michael Holick and Dr. Robert Heaney.
For those at moderate/average vitamin D deficiency Dr. Dowd recommends supplementing at 20 IUs/per pound and for those at highest risk (African Americans or a BMI over 30) he recommends a vitamin D dose of 25 IUs/pound. In real life: a 185 lb. man might supplement at 3700 IUs. A 300 lb. man might supplement at 7500 IUs. A 125 pound woman might supplement at 2500 IUs.
According to Dr. S, this has revolutionized his practice. By increasing his elderly patients' levels to the "best practice robust levels" of experts like Dr. Michael Holick and Dr. Bruce Hollis, he has seen "clinically satisfying success in a practice where there isn't a lot of success"--the chronically ill geriatric home-bound population. He sees the quality of life improve for both patients and their families, with improvements in functional mobility, walking, transfers, and mood--all without having to go to other prescription medicines. He has also seen improvements in chronic arthritis pain. Source: #749 Vitamin D Update Nov. 19, 2009 People's Pharmacy podcast
Source: James E. Dowd, M.D. The Vitamin D Cure. 2008
What's Dr. Hollis' reaction to Dr. S's Vitamin D experience with his elderly patients?
Hollis says he get emails and comments every week with similar positive effects of vitamin D. Resolved muscle pain, and reports of people who couldn't walk, or had to use a walker, and once they were put on adequate vitamin D they were able to walk. (my comment: this sounds almost like a faith-healing story--but who knows?) For Hollis, results such as Dr. S's are not uncommon.
As for a vitamin D/mood connection--Hollis says there's some evidence to suggest it's possible. There are vitamin D receptors in the brain and enzymes that metabolize vitamin D in the brain. Vitamin D definitely has neuro-functions, and Australian researchers studying its effect on rodents know that offspring born from vitamin D deficient mothers have dramatic brain deficits that are both physical and biochemical--and these deficits are never resolved. To Hollis this is a very scary prospect--thinking about humans raised in a vitamin-D deficient environment. He wonders about the potential for profound brain development deficits?
What about vitamin D toxicity?
Normal blood levels are 31ng/mL (lowest acceptable level) to 100 ng/mL. The optimum level would be 50-70 or 80 ng/mL, or whatever your physiological maximum level would be if you were fully sun-exposed--as are field workers or life guards. Hollis says he doesn't even know what vitamin D toxicity is--he's never seen it, and never saw any adverse effects in his pregnancy study where women took 4000 IUs/day. According to Hollis, there's little evidence of adverse effect under 10,000 IUs a day.
Since vitamin D is an immune regulator, and has a profound influence on autoimmune processes, it may be possible to see improvements in rheumatoid arthritis and a slowing of disease progression. However, vitamin D deficiency is more likely a trigger in developing autoimmune diseases like RA--not a cure for the disease.
The Iowa Women's Health Study found women taking vitamin D supplements were less likely to develop RA. And in a recent article a surprisingly high incidence of vitamin D deficiency was found in inflammatory joint patients even in a sunny Mediterranean country. Animal studies have shown reduced joint inflammation with vitamin D supplementation.
There are just a few clinical studies on vitamin D for treatment of RA--but in 3 of 5 studies researchers saw improvements in symptoms.
Vitamin D and osteoarthritisFrom Dr. James E. Dowd of The Vitamin D Cure: "The Framingham Study found a 2-3 fold faster rate of osteoarthritis progression in people who were in the lowest 20% of vitamin D levels compared to those in the highest." Boston researchers found that when vitamin D levels rise, people with osteoarthritis function better, and the severity of symptoms and disability are reduced.
Non-specific aches & pains in bones and muscles can be confused with osteoarthritis or fibromyalgia--but if it's caused by osteomalacia it will improve dramatically (may take 3-6 months) with adequate vitamin D.
Can adequate levels of Vitamin D really prevent colds & the flu?
The higher the vitamin D level the lower the risk of upper respiratory tract infections. According to Hollis there are ongoing studies on using vitamin D as an immune booster, and there is incredible evidence to show just how this works.
Vitamin D activates the "Rapid Response" component of our immune system, called the innate immune system which controls the production of natural "antibiotics" that attract bacteria & viruses. These processes aren't activated if someone is vitamin D deficient. And Hollis' pregnancy study offered conclusive proof that increasing levels of vitamin D absolutely controlled infection. "The vitamin D immune boost is a very real thing!"
What about the cancer connection? It seems so far-fetched.Dr. Hollis has collaborated with Dr. Walter Willett and the Harvard School of Public Health for over 15 years, studying epidemiologic data on the effects of vitamin D on cancer. These studies have routinely shown that an adequate vitamin D status protects against 13 or 14 different cancers, including breast, prostate, and colon cancer.
Hollis is skeptical that vitamin D could treat cancer once you get it--its benefit is in preventing it in the first place--and having adequate levels will lower your risk. Researchers in Nutrition Reviews project that a vitamin D blood level over 52 ng/mL would reduce breast cancer by 50%, and levels over 34 ng/mL would prevent 50% of the colon cancers.
Here's how it works: Vitamin D helps control cell growth and that's why we think that it will reduce the risk of many deadly cancers like prostate, breast, and colon by as much as 50 percent. In its role as a hormone, vitamin D travels all over our body delivering messages to activate genes and control cell growth.
If a cell turns cancerous, vitamin D delivers the instructions for that cell to self-destruct. Not enough vitamin D and that cancer cell might keep reproducing. According to Hollis, "vitamin D acts as a brake" when it comes to cancer. It prevents cells from growing wildly out-of-control--and this mechanism has been studied for years.
Explain the difference between D2 and D3. Is D3 superior?
D2 was commonly used in the U.S. because it was approved as a pharmaceutical in 1911. But Hollis doesn't like to use it. It's unnatural. It comes from yeast. It's functional, but D3 is preferable, and it's very easy to get these days. If you have the option--Hollis says, "Use D3".
How do you get enough vitamin D if you have a severe malabsorption syndrome, colitis or celiac disease?
If you can't absorb vitamin D supplements adequately, you clearly need to get your vitamin D from the sun. There are no vitamin D injections. When it comes to winter-time, dermatologists won't approve, but one option is short twice weekly visits to a sun tanning bed--10-15 minutes with face & neck covered with sunscreen. It is effective. Or play it safe and find out about getting controlled UV treatments in a medical setting.
What are normal vitamin D blood levels for children?
Hollis says normal levels for children are the same as for adults. "Do you think a rapidly growing child needs less vitamin D than a staid (no-longer-growing) adult?" A colleague of Hollis' in S. Africa recently measured blood levels of active-outdoor-playing children, both Black and Caucasian. Both had similar levels--around 50 ng/mL.
Please explain how vitamin D affects cardiovascular health.
There is a 142% increased risk of heart attack in vitamin D levels under 15ng/mL. According to Hollis, important recent research has shown that vitamin D acts as a natural statin, by decreasing inflammation. It doesn't lower cholesterol. It also prevents the infection-inflammatory processes and lowers blood pressure--both of which can contribute to damaged blood vessels, atherosclerotic plaque build-up, and clot formation.
Once you start taking vitamin D supplements how long will it take to increase your blood levels?
Hollis said most physicians should assume that their patients are vitamin D deficient, especially every person of color, and order a base-line blood level test--the 25-hydroxy-vitamin D test. For most people, supplementing with 2000-4000 IUs of vitamin D should be adequate. 1000 IUs will do very little except for a small child.
You'll need to wait 3 months before getting retested. If someone is very low, and depending upon their size, it could take months to get their levels up to optimal--50 ng/mL-70mg/mL.
What research on the horizon looks the most exciting?
Hollis is most excited about the current research on the effect of vitamin D on infections, as well as the multiple sclerosis/vitamin D research of Dr. George Ebers of Oxford University. Ebers recently discovered that vitamin D deficiency is an environmental trigger for multiple sclerosis.
"The Oxford University-led research, published in PLoS Genetics, suggests that vitamin D deficiency during pregnancy and the early years may increase the risk of offspring developing MS later in life." Click here to read more.
How about some "practice-based evidence" from primary care or internal medicine physicians?
Two comments from physicians in response to the Feb. 1, 2010 New York Times Vitamin D article were of particular interest to me.
Dr. Robert Baker
"The major problem with the proposed study is that it will give 2000 units of vitamin D a day without testing levels to determine an end point. 400 Units daily has been shown to raise levels only 5 ng., and 2000 Units daily has been shown in some studies to raise levels less than 20 ng.
I have tested 1800 people in primary care practice since 2005. 2/3rds are below 32 ng. but 1/3rd are below 20 ng., and 10% have levels in single digits. These figures are duplicated with published studies. So for many people raising the level even 20 ng. will not be enough.
The human body from sun alone will not make a level over 150 ng. A feedback mechanism breaks down vitamin D in the skin once this level is reached.
Lifeguards in August have been shown to have levels approaching this level. Humans evolving near the equator wearing scant clothing would also have had this level.
Sufficient vitamin D does not come from diet - amounts are small and several glasses of milk only have the small amount of 400 units of vitamin D because manufacturers add it.
So the wisdom of nature is already telling us the maximum level." Click here for the NYT link
Robert Baker MD
Primary Care Internal Medicine
Cherry Hill, NJ
[email protected]
Dr. Greg Plotnikoff
Vitamin D and PainMost clinicians who have read the literature and who prescribe vitamin D for patients based on their blood tests will affirm that replenishing vitamin D to a serum level of greater than 40 ng/ml can make a huge difference in chronic pain, muscular weakness and a wide range of non-specifc complaints.
The most impressive reports come from woman with muscle or bone pain on an aromatase inhibitor or persons with undiagnosed, chronic, non-specific musculoskeletal pain or unexplained significant muscular weakness.
No one with symptoms has fibromylagia or somatoform disorder until vitamin D deficiency has been ruled out or replenished.
Testing and replenishment is incredibly cost-effective.
The clinical effectiveness of D replenishment can be so profound, so unforgettable, that for practicing physicians there is no need for randomized controlled trials to assess the value of normalizing low vitamin D in persons who suffer.
Simply, test, replenish, monitor.
Why wait five years for a publication when one can have results of a blood test in a few days and results of replenishment in 2-6 months?
Asking this crucial question frustrates well-meaning researchers: Failing to ask this question frustrates patients.
— Greg Plotnikoff, MD
Thank you for your lucid and compelling coverage of vitamin D.
Do you have an idea where mainstream medicine is on the topic? Every doctor must be at least aware of vit D's new prominence, but what is common practice these days?
Positive Massage Therapy
Posted by: Steven | February 07, 2010 at 06:33 PM