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Benefits of vitamin D supplements still debated

April 4, 2014

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photo of Howard E. LeWine, MD

Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing

Howard LeWine, M.D., is a practicing internist at Brigham and Women’s Hospital in Boston, Chief Medical Editor at Harvard Health Publishing, and editor in chief of Harvard Men’s Health Watch. See Full Bio
View all posts by Howard E. LeWine, MD


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Deborah Miller
May 30, 2014

You have omitted a very important population of patients. There is STRONG evidence that people diagnosed with Multiple Sclerosis blood levels should be tested and supplemented if low. There is even evidence that it can be preventative of disease onset. Please comment.

May 30, 2014

My Teacher Advised for me Vitamin D Supplement is Good for Health. Visit

May 30, 2014

Vitamin D is a Good Supplement for Health & Wellness. Vitamin D Best for Women’s & Childrens

S. G. Xavier
May 16, 2014

I was told last year that my Vitamin D level was extremely low — ~12 ng/ml. Doctor said to take 4000 IU per day for about 6 months to bring it to normal ~35 ng/ml.

The prescription for D3 is outrageous expensive, so I got a bottle of “VitaFusion” Vitamin D3 2000 IU Gummies, which are delicious btw. My skinny, smoking friend with low VitD is doing what I did now since she tested very low also.

After 5 months of 2 per day, about 2 hrs after taking the gummies I felt really tired and exhausted, so I stopped taking them. About a month or so later, I went in for blood work and my Vitamin D level was perfect. I had reached the level and body was telling me, ENOUGH!

May 11, 2014

i get a trouble for along time
now i can see
thanks for you helping post

May 6, 2014

vitamin D protecting us from cancer and bone weakness, it very usful information Thanks to providing this type of info Keep doing.
May 4, 2014

what i really liked in your article, Mr.Howard, is that you described and explained well the need, requirement and intake of vitamin by different people at different stages of life. your post was worth reading, no doubt. thanks for sharing 🙂

May 1, 2014

While it’s true that vitamins cannot be used to substitute fruits and vegetables in a diet, many of the vegetables and fruit have very little vitamins left by the time they reach us (depending on where you live and the time it takes food to reach you). I, for example, live in South Africa in the inland. This means that most of the oranges in our country are driven across the country from near the coast. This can take several days or weeks. This means the vitamin C is virtually non-existent by the time it reaches me. So unfortunately I cannot rely on eating oranges for a vitamin C boost in the winter – I’ve had to find a reliable vitamin C supplement that can provide that for me.

As far as vitamin D goes, the only “natural” source other than food is sunlight. But as Mr. LeWine pointed out, too much sunlight poses the problem of skin cancer in the longrun. Or perhaps you live in a country where sunlight in itself is a rare commodity.

The question then, is there such a thing as a reliable vitamin D supplement? Well, it is well documented that the efficacy of vitamins (multi or single) is not consistently supported by science. I myself have found that certain brands of vitamins available in my country seem to be more effective than others. There are some brands of vitamins that are supported by studies or experiments, hence these brands are recommended by some general practioners (at least in South Africa) as a supplement to a well-balanced diet (not a replacement).

So unless you milk your own cows (or catch your own fish), or you live in an area where the produce in your store is truly “fresh from the cow” so to speak – a well-balanced diet rich in vitamin D foods is not going to suffice. You will have to do some research on brands and speak to your physician about a reliable source of vitamin D to supplement your daily intake.

April 30, 2014

It seems like every few years we have some vitamin or nutrient being touted as a cure-all and it is then aggressively pushed by the health/fitness and even medical establishment. Supplement sales soar and everyone feels a little better because after all, they are doing something good for their body.

In a few years vitamin D will be replaced by another and another and another. The issue is that it is almost impossible to isolate the effect of any given nutrient and then make mass recommendations to every single person across the board without an appreciation for their unique needs.

Outside of treating specific pathologies and using vitamin D like a drug, we should learn from the past and stop trying to promote a wonder drug. Instead we should encourage a focus on eating a balanced and diverse diet filled with fruit, veggies, and other whole foods and making recommendation based on a persons health and nutrient status. A person should be evaluated as a whole, taking into consideration symptoms and or health status and then making recommendations that are followed by reassessment to determine if we achieve a desired effect.

The research is great, but often times in the hands of the average person it becomes meaningless.

But all this supplementation (sometimes completely blind) based on tentative claims from a few marginal studies seems so contrary to what we do know about nutrition and good health. Any number of nutrients are essential for good health and a deficiency or even an imbalance of most will lead to less than optimal health.

Laurent Bolongola
April 30, 2014

Thanks,some goods advice about vitamin D. I really appreciate.

George A Tattersfield
April 30, 2014

Why no mention of the VITAL study being carried out by Harvard? I have been part of this study that is attempting to determine the benefits of both Vitamin D and Omega three fatty acids for about three years now. I personally believe that Vitamin D supplements have been aiding in my control of SAD.

Robert Bramel
April 30, 2014

What is the “normal”, well-regulated level of serum Vitamin D in individuals who receive abundant levels of sunlight? This ought to be baseline for any studies of vitamin D. It is obvious that ancestral man (in the days before windows and artificial lighting) has always been exposed to much more sunlight than modern man. Several studies suggest the body will stabilize serum vitamin D in the range of 60+ ng/ml. There has to be a reason why this level is established and this level has to be assumed to be better than lower levels. Studies that don’t calibrate to this “normal” level are highly suspect. Vitamin D is not like an artificial drug — in which the conservative assumption of serum level has to be zero.

dövüş oyna
April 22, 2014

The study addressed in the piece relied on studies using low doses of vitamin d less than 800IU a day many as low as 100 IU a day , vitamin d2 instead of D3 or high bolus doses . The IOM recommendations on vitamin d have been reviewed and critiqued by many , previous studies have established that 800iu a day as a minimum cutoff for example “Fall prevention with supplemental and active forms of vitamin D: a meta-analysis of randomised controlled trials.

Elina Ponting
April 16, 2014

Informative post. Keep sharing.

April 10, 2014

Post ran an excerpt of Liao’s essay last week, it led Franca Posner to remind readers about “one missing piece of this puzzle”: the patient’s perspective.

April 9, 2014

The effect of sun avoidance across a wide range of out comes has never been tested. the relationship between sun exposure and melanoma is not clear cut. Read ”
I BEG TO DIFFER; A Dermatologist Who’s Not Afraid to Sit on the Beach
Published: July 20, 2004 NYT.
Or ” Doctors Balk at Cancer Ad, Citing Lack of Evidence” NYT Published: July 10, 2007 which notes in part ….”And the link between melanoma and sun exposure is not straightforward. Dr. Marianne Berwick, an epidemiologist at the University of New Mexico who studies skin cancer, led a study published in The Journal of the National Cancer Institute in 2005 finding that people who had a lot of sun exposure up to the time they got a diagnosis of melanoma actually had better survival rates than those who had little sun exposure. The researchers are conducting a large-scale follow-up aimed at clarifying the relationship between sun exposure and melanoma.

Until that is made clear, many doctors say, it is premature to suggest that people are endangering their lives by failing to use sunscreen. ”

A recent study looked at this issue. “Skin cancer as a marker of sun exposure associates with myocardial infarction, hip fracture and death from any cause” Int. J. Epidemiol. (2013) doi: 10.1093/ije/dyt168 and found..”Conclusions In this nationwide study, having a diagnosis of skin cancer was associated with less myocardial infarction, less hip fracture in those below age 90 years and less death from any cause. Causal conclusions cannot be made from our data. A beneficial effect of sun exposure per se needs to be examined in other studies.”

Brandy | Bronze Booty
April 9, 2014

This is one of my gripes with the tanning community in general. I hear it always justified as “I need to get my vitamin D.”

This is why I stick with spray tans and take vitamin d supplements. I think debate about supplements will continue for a long time to come, but I much prefer taking supplements that might not work over getting skin cancer. Thanks for reporting on this research and your recommendations.


April 21, 2014

But I much prefer taking supplements that might not work over getting skin cancer.This is why I stick with spray tans and take vitamin d supplements. I think debate about supplements will continue for a long time to come, Thanks for reporting on this research and your recommendations.

nisar Ebrahim rathod
April 8, 2014

I’ve been living with this deficient vitamin12; for years unaware of the fact ,.. this deficiency created the start up of such high intensity retardant factors that nearly crossed the line to live a normal life,… though the will power truly defended the normalcy to speakout with volume in louder tone,.. and to step it forward nearly faltered to extent that body felt the uneasiness to walk, and to stood up with eyes shut was mere faltering disbalancing on foot,..only relief was B12 doses of ampule injected every week, caused the reversal as normal man.

Edmund Bertrand
April 8, 2014

Very nice article. It provide Very helpful information. I think vitamin D also help in maintaining Healthy body weight and to Protects from radiation damage.

vitamins supplements
April 7, 2014

I completely agree with you. One can get the required vitamin D from different foodstuff which are excellent sources of vitamins; however, my kid simply do not gulp anything of milk. Apart from plain milk, I tried making shakes and other recipes to make him have milk, but everything in vain. So is it safe? I mean I don’t want any kind of side-effects as such.

dövüş oyna
April 6, 2014

Nice. Thank you very much admin

Vito Goldfarb
April 5, 2014

I personally could care less what this or any other MD has to say, I just don’t trust any of you. First of all this idiot would think nothing of writing a script for poison to his patients!!!All of your adult patients have vit d deficiecys and everyone of them should also be supplementing with vit k mk7 in conjunction w/vitd3 to put calcium where it should be in your bones not your arteries. But a jackass like you didnt know thatmedically our country is all messed up as far as I’m concerned stick to pushing plavix and lipator and leave the supplementing to real Drs Sinatra, Weir, Mercola and Wong

George A Tattersfield
April 30, 2014

Such a pleasant and thoughtful reply to a well presented article. I really feel sorry for you!

Vince Miraglia
April 5, 2014

Convincing evidence also dose not exist for the expanded use of statins. Please read “Don’t Give More Patients Statins
By JOHN D. ABRAMSON and RITA F. REDBERG” Nov.13, 2013 which notes in part ….. “We believe that the new guidelines are not adequately supported by objective data, and that statins should not be recommended for this vastly expanded class of healthy Americans. Instead of converting millions of people into statin customers, we should be focusing on the real factors that undeniably reduce the risk of heart disease: healthy diets, exercise and avoiding smoking. Patients should be skeptical about the guidelines, and have a meaningful dialogue with their doctors about statins, including what the evidence does and does not show, before deciding what is best for them.”

Seems evidence is less important when economics interferes’

The study addressed in the piece relied on studies using low doses of vitamin d less than 800IU a day many as low as 100 IU a day , vitamin d2 instead of D3 or high bolus doses . The IOM recommendations on vitamin d have been reviewed and critiqued by many , previous studies have established that 800iu a day as a minimum cutoff for example “Fall prevention with supplemental and active forms of vitamin D: a meta-analysis of randomised controlled trials.
concluded …’Supplemental vitamin D in a dose of 700-1000 IU a day reduced the risk of falling among older individuals by 19% and to a similar degree as active forms of vitamin D. Doses of supplemental vitamin D of less than 700 IU or serum 25-hydroxyvitamin D concentrations of less than 60 nmol/l may not reduce the risk of falling among older individuals.’

In passing the IOM also has found no evidence for salt reduction below I believe 3200 a day. Several recent studys found no evidence that cutting saturated fat improved heart health. Seems no one really cares about evidence… or would adequate vitamin d level which many experts fell would require about 2000 to 4000IU a day reduce health care cost….

April 5, 2014

My 6 year old child has been advised vitamin d (D Must drops)for 6 months how safe is it for such a prolonged time

regards for such wonderful information

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