Vitamin D Milk

Serious Concerns About Multiple Vitamin D Studies

The term of art for this is an expression of concern. It sounds very restrained, but it is quite serious. Four papers about the effects of Vitamin D in the Journal of Nutrition recently earned this dubious distinction. Add that to a paper in PLOS ONE that is getting the same sort of scrutiny. In addition, the American Journal of Clinical Nutrition has issued another such concern on a Vitamin D paper. So, too, has Frontiers in Pharmacology. This is an impressive cascade of concerns about Vitamin D studies in just a few weeks.

Data Sleuths Finding Issues

Six of these seven papers come from a research group at the Kashan University of Medical Sciences in Iran. Retraction Watch reports that this group has been attracting attention for several years now. Last year, data sleuths notified journals about suspicious findings in 172 research papers from that group.

Thus journals have now flagged more than three dozen papers from those researchers as having issues.

What Gives With Vitamin D?

It’s hard to miss the fact that vitamin D evokes strong reactions. Every time the subject comes up on ConscienHealth (e.g. here), the interest from readers is intense. Of course part of the interest is because of observational studies about vitamin D and COVID-19.

But as Dean David Allison of the IU Bloomington School of Public Health pointed out to us, the emotions attached to the word vitamin may also play a role. Research tells us that this word evokes significant positive emotions. Call it cholecalciferol or an acute toxin and the emotional response is very different.

As vitamin D, it has a warm and fuzzy image – something inexpensive that’s good for you.

Burned by Vitamin D Before

Writing on Medscape, Perry Wilson warns us to be cautious:

“Low vitamin D levels have been linked to so many things. Vitamin C deficiency causes scurvy — fine. But low vitamin D has been linked to everything from Alzheimer’s to whooping cough. It’s either the most important vitamin in the world or it’s a stand-in for some other important thing.

“When we’ve tested all of these intriguing links via randomized trials, giving some people vitamin D and some placebo, they almost always showed no effect.”

So you can call us cautious. The best bet if you suspect you might have a problem with vitamin D is to ask your doctor to check your levels. Vitamin D presents a Goldilocks problem. Too little is not good, nor is too much. We need to get this just right – based on good evidence. Not feelings.

Click here for further perspective from Perry and here for more from Retraction Watch on the issues at Kashan University of Medical Sciences. For the Vitamin D papers with problems, click here, here, here, and here.

Vitamin D Milk, photograph © Roxanne Ready / flickr

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November 16, 2020

20 Responses to “Serious Concerns About Multiple Vitamin D Studies”

  1. November 16, 2020 at 7:09 am, Al Lewis said:

    Weren’t some earlier papers on Vitamin D authored by someone who it turned out had a connection to one of the manufacturers?

    • November 16, 2020 at 12:22 pm, Ted said:

      Al, one of the concerns on the PLOS ONE study was undisclosed competing interests. But the concern was not as specific as you are suggesting.

  2. November 16, 2020 at 10:09 am, David Brown said:

    It’s called the flu season because viral infections are more common during the cold months in higher latitudes. In climates where vitamin D can be activated year-round, the COVID-19 mortality curve rises and flattens as the virus works its way through the population. Eventually, it declines and flattens. In colder climates the curve rises steeply, falls steeply, flattens out, and stays that way if herd immunity has been achieved. If herd immunity has not been achieved, a second rise and decline happens during the cold months. Initially, Michigan[1] and Sweden[2], with similar populations, had similar mortality curves. However, Sweden has proportionately fewer dark-skinned people who are at a disadvantage vitamin D-wise in higher latitudes. So as the flu season advances, COVID-19 mortality is lower in Sweden than in Michigan. Note that in Brazil[3], the Daily Deaths curve is gradually declining as that country slowly approaches herd immunity.

    Web page references

  3. November 16, 2020 at 1:53 pm, Chela said:

    Todo parece muy bien escrito pero para quienes escriben todo lo q le hace falta saber a las gentes es. Q diferencia hay entre las vitamina D3 u d2 q cantidad se toma u cuáles porq cuando vas a las farmacia ni sabes cuál llevar y porq no se vende la d2 y si esa ya suple la necesidad de no tener q tomar otra cuando el dr te da esa recetada una por semana. Ojalá entiendan lo q pregunto porq lo q ustedes escriben no es para las gentes normales eso no nos interesa solo q necesitamos tomar y no tanta variedad.

  4. November 16, 2020 at 4:16 pm, LInda Pahl said:

    I am female and 63 years old. When I was about 51 years old and it was spring time, all of a sudden my bones, joints started to ache. I became tired throughout the day for about a week. The second week my whole body ached fiercely and I was extremely exhausted. My primary doctor ordered a vitamin D 25-Hydroxy blood test and other blood tests. My vitamin D level was below normal limits. Doctor recommended vitamin D3 oral liquid cap twice a day. After taking vit D3 for one week I had complete relief for body aches. My energy level was back to normal. I to this day continue to take vitamin D3. And have a yearly Vitamin D3 blood test. I also try to get 20 minutes of sun 3 times per week even during the winter months. I live in Wisconsin. Go visit your doctor and ask for a Vitamin D 25-Hydroxy blood test first before you start taking Vitamin D3. He can advise you on how much to take.

  5. November 16, 2020 at 7:22 pm, Don n said:

    My Endocrinologist in NH was very upset when my levels measured @ 16. He told me that my goal is 80 … That was back in 2011 … I’m now @ 55 in 2020 & some Docs have said 55 is almost too high. Not that I don’t trust them, but i trust my Endocrinologist & will continue to attempt to increase it to 80 levels…

  6. November 16, 2020 at 9:52 pm, Cindy said:

    I visited my doctor last year very sick. Bloodwork showed a D deficiency. I took vitamine D once a week for 3 weeks and was back to normal. Recently, I forgot to take it for 2 weeks and started to feel sickly. I took it today. I’ll bet I’m much better in the am.

  7. November 17, 2020 at 8:39 am, Lena Elkins said:

    I have been on vit d3 for 10 yrs my levels were 13 discovered when had hip relacmet. My levels are 50 now I. Take 4000 be without it. I am 82

  8. November 17, 2020 at 11:11 am, Marie Davenport said:

    I am 83 with little or no pain and my husband is 74 with no daily pain a little arthritis. We have been talking D3 for 5 years daily.

    I do believe in vitamins. we take vitamin c daily too. Even if you take a multi vitamin, keep taking D3.

    • November 17, 2020 at 12:00 pm, Ted said:

      I’m glad you’re doing well. The wisdom of taking vitamin D is an individual thing, depending on how much you take and what your vitamin D levels are.

  9. November 17, 2020 at 11:46 am, Ann Livingstobe said:

    10 years ago, I went to Houston emergency room thinking I broke my foot. Ex ray said no. It was softening of bones, was on crutches, couldnt stand on foot. Wanted to do surgery. Started D3, immediately pain ceased, got rid of crutches. Onlyvwhen i go without D3, si i have issues. I was 52 when it started. Am 63 now. Cannot be in sun due to fairness. Milk , am allergic to. Vit D3 saved the day! Any doctor, GYN, family doc ect. tells me to keep it up. ..

    • November 17, 2020 at 11:56 am, Ted said:

      That sounds wise, especially if you are keeping track of your levels.

  10. November 17, 2020 at 2:07 pm, Mary said:

    Vitamin D3 is very important to the body. I am 56, my annual bloodwork showed my level to be under the lowest acceptable range for normal. I was achy all over and my bones hurt, I was exhausted all the time, had major sleep issues, terrible hot flashes. I started taking K2 + D3, it’s been one month now and have no aches, I sleep well, my hot flashes have largely decreased in how often and in severity. I will continue without media scare. My doctor’s advice is what I go by. My husband is 61, had major surgery to remove an ulcerated melanoma from the heel of his foot (with reconstruction and skin graft) When he went back to work, his foot swelled enormously. (Truck driver) He started taking the K2 + D3 and he feels better physically. In addition, the inflammation in his foot has nearly gone. I’ll say it again, we follow our doctors advice and ignore media fear mongering. It’s shameful to see so many living afraid of Covid-19, and now it’s starting on everything and anything found to help reduce symptoms of the blown-out-of-proportion effects of the new covid virus.

    • November 17, 2020 at 4:16 pm, Ted said:

      Mary, you’re very smart to follow your doctor’s advice.

  11. November 17, 2020 at 10:10 pm, Dr Templeman said:

    Vitamin D is a hormone and there are receptors for it on every cell virtually in the body. Too many academics have knee jerk reactions about any supplement. Not surprising that they wish to downplay its value for health. It’s benefits are like an iceberg and the science on it is only the tip. Watch out for continual good news for the next 2 decades as the science catches up.

    Show me a case of overdose and I will start to take the scepters seriously. Until then keep supplementing daily with far more than recommended. Better yet get a Nano sized supplement for better absorption and effect.

  12. November 17, 2020 at 11:37 pm, Barbara Albert said:

    How much is too much ?? I really need to know ! Will someone please answer me ?

    • November 18, 2020 at 10:53 am, Ted said:

      Barbara, I cannot recommend strongly enough that you consult with a healthcare professional who can offer advice tailored to your specific health needs. The internet makes a lousy substitute for a doctor or an RDN.

  13. November 18, 2020 at 2:16 am, Scott Henrie said:

    Because magnesium is needed to activate vitamin D.

    “role of magnesium in vitamin D activation and function”

    • November 18, 2020 at 10:50 am, Ted said:

      True enough, Scott, but determining the status of magnesium sufficiency is no simple matter. Nutritional deficiencies are best diagnosed by professionals who know what they’re doing.