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Newsletter: Vitamin D questions and answers

Posted on: April 15, 2008   by  John Cannell, MD


Professor Marshall’s recent “discovery”

Dr. Cannell: I understand Dr. Marshall conducted a study and found vitamin D is bad for you. What kind of study did he do? Mary Minneapolis, MN

I have been inundated with letters asking about Professor Marshall’s recent “discovery.” Some have written that to say they have stopped their vitamin D and are going to avoid the sun in order to begin the “Marshall protocol.” The immediate cause of this angst is two publications, a press article in Science Daily about Professor Marshall’s “study” (which is no study but simply an opinion) in BioEssays. Dr. Trevor Marshall has two degrees, both in electrical engineering. Before I begin, I want to again remind you that I am a psychiatrist who works at a state mental hospital. In my duty to full disclosure, I must say that I have known a lot of psychiatrists in my life and a few electrical engineers. If I knew nothing else of a disagreement between two people but their professions, I would believe the electrical engineer, not the psychiatrist.

In reading his two articles, Dr. Marshall’s main hypotheses are simple:

  1. Vitamin D from sunlight is different than vitamin D from supplements.
  2. Vitamin D is immunosuppressive and the low blood levels of vitamin D found in many chronic diseases are the result of the disease and not the cause.
  3. Taking vitamin D will harm you, that is, vitamin D will make many diseases worse, not better. If you read his blog, you discover that the essence of the Marshall protocol is: “An angiotensin II receptor blocker medication, Benicar, is taken, and sunlight, bright lights and foods and supplements with vitamin D are diligently avoided. This enables the body’s immune system, with the help of small doses of antibiotics, to destroy the intracellular bacteria. It can take approximately one to three years to destroy all the bacteria.” That is, Dr. Marshall has his “patients” become very vitamin D deficient.

Again, Dr. Marshall conducted no experiment and published no study. He wrote an essay. He presented no evidence for his first hypothesis (sunlight’s vitamin D is different than supplements). From all that we know, cholecalciferol is cholecalciferol, regardless if it is made in the skin or put in the mouth. His second hypothesis is certainly possible and that is why all scientists who do association studies warn readers that they don’t know what is causing what. Certainly, when low levels of vitamin D are found in certain disease states, it is possible that the low levels are the result, and not the cause, of the disease. Take patients with severe dementia bedridden in a nursing home. At least some of their low 25(OH)D levels are likely the result of confinement and lack of outdoor activity. However, did dementia cause the low vitamin D levels or did low 25 (OH)D contribute to the dementia? One way to look at that question is to look at early dementia, before the patient is placed in a nursing home. On the first day an older patient walks into a neurology clinic, before being confined to a nursing home, what is the relationship between vitamin D levels and dementia? The answer is clear, the lower your 25(OH)D levels the worse your cognition.1, 2

These studies suggest that the low 25(OH)D levels are contributing to the dementia but do not prove it. Only a randomized controlled trial will definitively answer the question, a trial that has not been done. So you will have to decide if vitamin D is good for your brain or not. Dr. Marshall seems to be saying demented patients should lower their 25(OH)D levels. Keep in mind, an entire chapter in Feldman’s textbook is devoted to the ill effects low vitamin D levels have on brain function.

It is true that in some diseases, high doses of vitamin D may be harmful. For example, in the early part of last century, the AMA specifically excluded pulmonary TB from the list of TB infections that ultraviolet light helps. They did so because many of the early pioneers of solariums reported that acutely high doses of sunlight caused some patients with severe pulmonary TB to bleed to death. Thus, these pioneers developed very conservative sun exposure regimes for pulmonary TB patients in which small areas of the skin were progressively exposed to longer and longer periods of sunlight. Using this method, sunlight helped pulmonary TB, often to the point of a cure. Furthermore, it is well known that sunlight can cause high blood calcium in patients with sarcoidosis. In fact, sarcoidosis is one of several granulomatous diseases with vitamin D hypersensitivity where the body loses its ability to regulate activated vitamin D production, causing hypercalcemia.3

Furthermore, although medical science is not yet convinced, some common autoimmune diseases may have an infectious etiology. I recently spoke at length with a rheumatologist who suffers from swollen and painful joints whenever he sunbathes or takes high doses of vitamin D. As long as he limits his vitamin D input his joints are better. To the extent vitamin D upregulates naturally occurring antibiotics of innate immunity, sunlight or vitamin D supplements may cause the battlefield (the joints) to become hot spots. I know of no evidence this is the case but it is certainly possible.

However, if Dr. Marshall’s principal hypothesis is correct, that low vitamin D levels are the result of disease, then he is saying that cancer causes low vitamin D levels, not the other way around. The problem is that Professor Joanne Lappe directly disproved that theory in a randomized controlled trial when she found that baseline vitamin D levels were strong and independent predictors of who would get cancer in the future. The lower your levels, the higher the risk. Furthermore, increasing baseline levels from 31 to 38 ng/ml (77.5 to 95 nmol/L) reduced incident cancers by more than 60% over a four year period. Therefore, advising patients to become vitamin D deficient, as the Marshall protocol clearly does, will cause some patients to die from cancer.4

I will not write again about Dr. Marshall’s theories. No one in the vitamin D field takes him seriously. Personally, I admire anyone willing to swim against the tide and raise alternative theories. I have done the same with influenza and autism. However, I agree with the New York Times and Jane Brody’s conclusion: “In the end, you will have to decide for yourself how much of this vital nutrient to consume each and every day and how to obtain it.”

Degenerative Arthritis

Dr. Cannell: I am a 54 year old obese African American woman who started my vitamin D journey by taking 2,000 IU/day. Being obese, over 350 pounds, that amount of supplementation didn’t do much for me. I eventually increased my supplementation to 300,000 IU/day for 8 months. I have severe SAD; vitamin D has helped my SAD and gave me more strength and flexibility. When I saw my doctor my 25[OH]D was 242 ng/ml, with normal calcium. My doctor advised me to stop supplementing with vitamin D or to cut my dose in half.

Over the years I developed degenerative arthritis in my knees. Finally my knees deteriorated to the point of bone rubbing on bone. Shortly thereafter, my specialist advised knee replacements. That is when I started injecting vitamin D directly into the area around my knees. The pain went away almost immediately but it took much longer for my mobility to come back. Now I can walk more easily for long distances and without pain.

I did cut my dose down but was still taking about 100,000–150,000 IU of vitamin D3/week and injecting my knees monthly with 300,000 IU. My last 25[OH]D was 462 ng/ml, again with normal calcium levels. That’s when I decided to stop taking the vitamin D3 unless I start to feel under the weather. At the end of March last year I weighed 347 pounds; in October I weighed 292 pounds. As long as my calcium is normal, is it ok to keep taking these amounts of vitamin D? Will injecting into my knees hurt me? Fay Washington, DC

No, it is not ok to take that amount of vitamin D—and injecting it into your knees is a first for me! The first sign of vitamin D toxicity is hypercalcuria (excess calcium in the urine), not hypercalcemia (excess calcium in the blood). As vitamin D must be transported in the blood to be hydroxylated by the liver, you should get the same effect for your knees by injecting it in your elbows and I don’t recommend either. The amount of vitamin D you are taking and your 25(OH)D levels indicate you will calcify your internal organs, starting with your kidneys.

I advise lowering your 25(OH)D down to less than 100 ng/ml by immediately stopping all vitamin D and staying out of the sun. I’m glad you have lost so much weight and there is reason to think vitamin D will induce weight loss. However, one does not need the doses you are using to induce weight loss. Fay, what you are doing is experimenting with vitamin D as a pharmaceutical agent, not a supplement. It may be that future studies will show pharmaceutical doses of vitamin D (50,000 IU per day) do have a treatment effect on certain diseases. To date, no studies support what you are doing and other studies indicate you are taking toxic doses of vitamin D. Again, stop your vitamin D and stay out of the sun.

Sunshine and Pericarditis

Dr. Cannell: I have pericarditis and retired about 3 months ago. Once I started getting out and sunbathing in my bathing suit my symptoms disappeared! Thank you very much. When I went to my doctor, he was amazed at my improvement but refused to believe sunshine had anything to do with it. He said he had never heard of sunshine curing pericarditis! Jeanne San Diego, CA

No, like your doctor I have never heard of it either, but unlike your doctor I believe it is possible the sunlight cured your pericarditis. The majority of cases of pericarditis are infectious with viruses the most common agent. Sunlight will trigger formation of antimicrobial peptides, which are potent and broad spectrum antibiotics. Anyone who takes more than 2,000 IU per day knows that lower respiratory infections are less common and by sunbathing in your bathing suit your were getting about 10,000 IU per day.

Vitamin D – Helpful for Heartbeat?

Dr. Cannell: For as long as I can remember I have been subject to missed heart systolic beats. I went to a heart specialist about it. He did ECG, etc. and told me that he thought anxiety might be involved as he had the same thing once. In any case my missed systole happened anytime, anxiety or no anxiety. When I got the message from you that vitamin D was involved in heart action I started taking 2000 IU a day. The missed systole stopped after about two months and it is no longer with me. Was it the vitamin D? Dan Seattle, WA

I don’t know. If your vitamin D level was low enough to affect you blood calcium the vitamin D would help that. Without 25(OH)D levels, there is no way of knowing what your level was or if your level is in the ideal range now. I personally know of a patient with severe heart disease who refused to go to the hospital. He was on standard medical therapy plus 5,000 IU per day. However, both his severe congestive heart failure and his arrhythmia improved after he started taking 10,000 IU per day.

A case report found sick sinus syndrome disappeared after vitamin D. Other than the case report, I’m not aware of any literature on the subject, one way or the other.5

Blood Test Only Way To Know

Dr. Cannell: Personally, I am at 6000 IU per day. After taking 4000 IU per day for 2 months I was still deficient at 15. So based on my weight (285 pounds) I bumped it up. And I haven’t had a cold or flu in over 2 years. No bronchitis either and my bronchitis usually bothers me all winter. Thank you. What can I do to help spread the word? Bill Boston, MA

Your case highlights the need to get repeat blood tests. I’ve been surprised at just how ineffective supplementation can be, especially in obese patients. One has to supplement, get 25(OH)D blood test, adjust supplementation, get another level, etc. Many obese people will need 10,000 IU per day to obtain a level of 50 ng/ml (125 nmol/L), but getting a 25(OH)D is the only way to know how much you need to take. And, levels will go higher in the summer due to incidental sun exposure.

It is becoming widely known that adequate doses of vitamin D helps prevent colds and flu. I’m proud of the fact that the first time such a finding was ever published in the world’s literature, it was published by the Vitamin D Council in our November 2005 newsletter.

As far as helping is concerned, the Vitamin D Council would like to run a national advertising
campaign. We did run three ads in parts of California to the tune of $4,800. You can see the three ads on our Vitamin D Council YouTube Channel. We would like to run them all around the country but that would cost more than $200,000.00. We need contributions before we can run anymore.

Vitamin D Overdose

Dr. Cannell: I seem to be reacting to Vitamin D pills even at the 400 IU level with dry eye and mouth. Please address overdose symptoms for Vitamin D as any good advice column should do. Can you also address what a person like me should do to absorb Vitamin D supplements? Can a person get Vitamin D from the tanning machines? I hope you take my recommendations to heart. Your web site is valuable and could be more helpful to all. Roberta Fairfield, CT

The symptoms of vitamin D toxicity are weakness, nausea, vomiting, pain in the joints, loss of appetite, and weight loss. The patient may experience constipation alternating with diarrhea, or have tingling sensations in the mouth.

The toxic dose of vitamin D depends on its frequency. In infants, a single dose of 15 mg (600,000 IU) or greater may be toxic, and has to exceed 0.5 mg (20,000 IU) per day over a prolonged period to be toxic in infants. In adults, a daily dose of 1.0–2.0 mg (40,000–80,000 IU) of vitamin D may be toxic when consumed for a prolonged period. A single dose of about 50 mg (2,000,000 IU) or greater is probably toxic for adults. The immediate effect of an overdose of vitamin D is abdominal cramps, nausea, and vomiting, not dry mouth and eyes. Toxic doses of vitamin D taken over a prolonged period of time result in deposits of calcium crystals in the soft tissues of the body that may damage the heart, lungs, and kidneys.

For people who have trouble with supplements, I recommend sunbathing during the warmer months and sun tanning parlors in the colder months. Yes, sun tanning parlors make vitamin D, the most is made by the older type beds. Another possibility is a Sperti vitamin D lamp.

Dr. Cannell: I am a pain management physician in Grand Rapids MI. and I prescribe a lot of vitamin D. Typically I write for 50,000 IU as a weekly tablet and dispense this to a lot of my elderly patients with osteoporosis. Occasionally one of them takes it daily because they cannot or do not read their label on the bottle.

My most recent patient to do this is a 75 year-old female weighing about 250 pounds. She has had nonhealing venous stasis ulcers in bilateral lower extremities for over 5 years despite the best efforts of the local wound care clinic. When she received her prescription for vitamin D she proceeded to take it daily until all 13 tabs were gone. When I saw her at her next visit we caught her mistake, wrote her for a new RX and made sure she knew how to take it. However, since her accidental overdose, the wounds have started healing! The one on her left leg is completely healed and the right one is closing rapidly. Do you think the vitamin D could have had something to do with this? Dr. Mark Grand Rapids, MI

I don’t know but this is another example of the use of pharmaceutical doses of vitamin D (this one by mistake). Vitamin D upregulates antimicrobial peptides in the skin, which promote healing. After World War One, solariums were common treatment for non-healing war wounds. I think you should measure 25(OH)D levels on all your patients. If you do, I think you’ll find that 50,000 IU per week is giving your patients levels between 50–80 ng/ml (125–200 nmol/L), which is fine.

Professional Athletes Need Vitamin D Too!

Dr. Cannell: After reading your previous newsletter, I looked for and found a definite correlation between the average UV radiation in a state and the number of quality athletes the state produces per million population. Hawaii is way in front and the southern states way ahead of northern states. I’ve also found a correlation of multiple super bowl appearances/wins with team geographic UV radiation. I’ve also found a correlation between the per capita number of PGA golfers (with most annual wins) and UV radiation (not published yet). Thought you might find my website of interest: Sunshine and Peak Performance. Tonis Greensboro, NC

Good work. And once again, the first reference in the world’s literature that vitamin D will help athletes was published by the Vitamin D Council in our March 2007 newsletter. Can you imagine what will happen in professional sports when athletes realize that vitamin D improves their speed, strength, timing, and quickness?

Sunlight Needed For mal-absorption

Dr. Cannell: I am not able to raise my 25(OH)D levels past 38 nM/L and I am on 8,000 IU D3 a day now! (trying for 2 years) I have gut issues. So, I am thinking that maybe Calderol or Dedrogyl might be appropriate. Can you lead me to links on that aspect? I have fibromyalgia and osteoporosis. I would like to talk about this with my doctor. Mary Quebec, Canada

You didn’t give your weight so I don’t know if you’re not absorbing it or it is depositing itself in fat tissues. I suspect you are not absorbing it. The two prescription items you mentioned, Calderol and Dedrogyl, are both 25(OH)D. Although they are effective, there is no reason to use them unless your liver is not hydroxylating vitamin D. I suspect that your level would be fine if you started using a sun tan parlor twice a week. Or, you could go to 10,000–15,000 IU per day. However, at that dose, you should get your 25(OH)D level checked every four months. For malabsorption syndromes, a sun tanning parlor once or twice a week is ideal or a home vitamin D lamp.

Vitamin D and COPD

Dr. Cannell: Thank you! I have been reading quite a bit on Vitamin D deficiency on your website. Very, very interesting! Thank you too, for the great work you’re doing in getting the word out! I’ll be spending a lot more time on the shores of Lake Mich. again this summer! I’m also supplementing with D this winter. About 5 years ago I was diagnosed with COPD, I had a respiratory incident last fall and was hospitalized and after that I started taking 5000 IU per day. I want you to know that I ran up the steps from the mail box this morning and yesterday morning. I haven’t done that in years. I am a 55 year old female who smoked for almost 30 years. Very anecdotal but it’s happening. I can breathe deeper too. I don’t know how I can thank you. Debbie South Bend, IN

COPD appears to respond to vitamin D in two ways. It improves pulmonary function through an unknown mechanism and it prevents lower respiratory infections that usually exacerbate underlying lung disease. As far as helping, we need donations in order to run a national TV advertising campaign.

Arthritis and Prostate Cancer

Dr. Cannell: I have been taking 10,000 IU vitamin D per day for over three years and my arthritis and prostate cancer are gone (at least my PSA returned to normal) and I am paddling my canoe and starting to run again and feel much stronger now. I had my 80 birthday this July. Thank you for your website and newsletter. I think I’d literally be dead without it. Frank Waterbury, CT

You’re welcome. While there are no interventional trials using vitamin D in arthritis, cross sectional and longitudinal epidemiological studies suggest it would have a treatment effect. Professor Reinhold Vieth, in an open trial, discovered that 2,000 IU of vitamin D per day slowed the rate of growth of PSA. Other men with prostate cancer have written to me that their PSA returned to normal with higher doses of vitamin D although it takes up to a year.

Increased Body Fat? More ‘D’ Needed

Dr. Cannell: I’m a physician and many of my patients have difficulty getting a normal 25(OH)D, even with 4,000 Units per day over 4 months. Did you read anything about resistance to vitamins D supplementation? Thank you for all your work. A bit of good news: in France the labs have put up the normal level of blood vitamins D from 20 ng/ml to 30 ng/ml. Doctor Philippe Paris, France

The resistance is probably due to the relatively low dose and patient’s body fat. Many larger adults need 5,000–10,000 IU per day to get adequate levels. I’m glad they have increased the lower limit in France. However, it should be 40 and not 30. Remember Bruce Hollis, in a crucial paper, showed that the kinetics of vitamin D’s metabolism is not normalized until levels are above 40 and often 50. His discovery is compelling evidence that levels of 40–50 represent the lower limit of the ideal human range.6


Dr. Cannell: I am a family physician in Edmonton, Alberta Canada I was fascinated by the information regarding plausible causation of autism and vitamin D and would love to have more information on this. Over the past two years testing and then repleting patients with vitamin D has revolutionized my practice with so many conditions improving. I have been absolutely astonished at how many different diseases respond. Dr. Gerry Edmonton, Canada

You are not alone. One of the Kaiser hospitals in California is now drawing 25(OH)D levels on all of their subscribers. I know of at least 10 clinics doing the same and treating with adequate doses of vitamin D. They all report that a wide variety of diseases respond. The one exception is advanced cancers and that is to be expected as poorly differentiated cancers lose the ability to activate vitamin D and lose the vitamin D receptor. However, if I had an advanced cancer, I’d still take 20,000 IU per day.

As far as autism goes, I have been unable to interest any autism researchers, even those drawing routine blood of the children, and even at my alma mater, UNC School of Medicine. I continue to believe that gestational and/or early childhood vitamin D deficiency is a major cause of autism. My paper is being distributed this month although I doubt any researchers will act on it.7

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