The rise and inevitable fall of Vitamin D

[HuckleB]

https://www.sciencebasedmedicine.org/the-rise-and-inevitable-fall-of-vitamin-d/#more-42613

"It’s been difficult to avoid the buzz about vitamin D over the past few years. While it has a long history of use in the medical treatment of osteoporosis, a large number of observational studies have linked low vitamin D levels to a range of illnesses. The hypothesis that there is widespread deficiency in the population has led to interest in measuring vitamin D blood levels. Demand for testing has jumped as many physicians have incorporated testing into routine care. This is not just due to alternative medicine purveyors that promote vitamin D as a panacea. Much of this demand and interest has been driven by health professionals like physicians and pharmacists who have looked at what is often weak, preliminary and sometimes inconclusive data, and concluded that the benefits of vitamin D outweigh the risks. After all, it’s a vitamin, right? How much harm can vitamin D cause?

There’s no lack of research on vitamin D. Unfortunately, much of that research has been observational, which can find interesting correlations, but can’t demonstrate cause and effect. While there have been some high-quality, large prospective trials using vitamin D as a therapy, there are also a huge number of smaller, poor-quality trials, many of which have produced positive results that haven’t been replicated in larger studies. The net effect has been lots of positive press, but some persistent questions that may not be as widely understood. A new paper from Michael Allan and colleagues set out to summarize the evidence base for vitamin D across multiple uses. It was published in the Journal of General and Internal Medicine, and is entitled “Vitamin D: A Narrative Review Examining the Evidence for Ten Beliefs.” And scanning the list, most of the common claims and beliefs are there: osteoporosis, falls, colds and the flu, cancer, etc. As a narrative review, it is important to note that this type of paper has a high risk of bias. The authors do state that they preferentially sought out systematic reviews and meta-analyses (which, when well conducted, can produce very objective information) but when wrapped in a narrative commentary, the risk of bias increases. This doesn’t mean the findings are incorrect, but that the conclusions emerging from a narrative review (compared to a well-conducted systematic review) will be less robust and quantifiable. While the paper is behind a paywall, I will touch on each of the myths and the evidence they cite, because the paper neatly summarizes the overall evidence base for many of the claims made for vitamin D that I and other contributors have discussed in past posts.

...

#10: No role for routine vitamin D testing

There’s a lack of evidence to demonstrate that routine vitamin D testing is necessary. The Choosing Wisely campaign recommended against routine testing as the results of the test are not likely to change the medical advice you’ll receive, which includes basic lifestyle advice (stop smoking, control your weight, be active, and to focus on getting your vitamin D from food and the sun). Despite the recommendations against testing, it has become widespread: In 2011, US Medicare spent $224 million on vitamin D tests for seniors.

Conclusion: More hype than hope

Despite the correlation of low vitamin D levels with an array of medical conditions, the evidence for supplementation remains unconvincing for most uses. Given the modest benefit, low cost, and relative lack of side effects, vitamin D, when used with calcium, retains a role in the prevention of fractures, along with the possibility it may modestly reduce falls and mortality. As for testing, you might need one if you have osteoporosis, or have any medical condition that affects your ability to obtain or use vitamin D. In the broader population, there’s no clear need for testing at all. This area, like a lot of nutritional research, is plagued with lots of low-quality evidence that is more than likely to steer us in the wrong direction. Until better evidence emerges, taking a cautious approach to vitamin D seems sound. Supplementation at modest doses is safe. If you do decide to supplement, remember that more isn’t better, and keep your dose low enough to avoid potential harms."

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The author, a pharmacologist, assesses the state of the science for several claims regarding Vitamin D supplementation.

Good info!

[SheilaT]

1. Thanks for posting this.

There are people out there, some of whom post on other parts of DU, who will claim that vitamin D is a miracle vitamin, that most people are deficient in it, and so on.

Too bad none of them will read this.

[peace13]

2. Two winters ago my level tested at 13.

I was glad that my doctor ran the test. we all have different experiences and ideas.

[packman]

3. Been on D3 for years, good so far

with heart condition and all related crap (kidneys, liver, etc.) that goes with it while wife on same regimen (osteoporosis). From a purely anecdotal standpoint I believe I am less prone to infections and colds and for years been getting same results from check ups from various doctors seen that all is good and maintaining healthy levels.

[womanofthehills]

4. Actually, lots of new research coming out on benefits of Vit D - breast cancer, prostate cancer

ETSU scientists make discovery about possible Vitamin D benefits
JOHNSON CITY, Tenn. -

Scientists at ETSU’s Quillen College of Medicine have discovered vitamin D could be beneficial for more than strengthening bones. The vitamin could actually lessen calcification in soft tissue.

"Vitamin D could regulate calcification and it turned out when you put more Vitamin D on to conditions where you get more calcification, you can protect against the calcification,” Dr. Matt Keasey, a research associate in the Department of Biomedical Sciences.

Kease added that soft tissue calcification is most common in the elderly but no matter the age, your body needs it. Vitamin D is mostly absorbed through sunlight, but it can be found in supplements as well.

http://www.wcyb.com/news/etsu-discovers-vitamin-d-benefits/40298510

Vitamin D deficiency contributes to spread of breast cancer in mice, study finds

If you go over to Sciencedaily.com their are more studies of Vit D and pregnancy that are very interesting.

Date:
March 2, 2016
Source:
Stanford University Medical Center
Vitamin D deficiency contributes to spread of breast cancer in mice, study finds

Breast tumors in laboratory mice deficient in vitamin D grow faster and are more likely to metastasize than tumors in mice with adequate levels of vitamin D, according to a preliminary study by researchers at the Stanford University School of Medicine.
from Sciencedaily.com

Low vitamin D predicts aggressive prostate cancer
Low level of vitamin D at time of surgery is linked to potentially lethal cancer in men
https://www.sciencedaily.com/releases/2016/03/160301131117.htm

Date:
March 1, 2016
Source:
Northwestern University
A new study provides a major link between low levels of vitamin D and aggressive prostate cancer. Northwestern Medicine research showed deficient vitamin D blood levels in men can predict aggressive prostate cancer identified at the time of surgery.

The finding is important because it can offer guidance to men and their doctors who may be considering active surveillance, in which they monitor the cancer rather than remove the prostate.

"Vitamin D deficiency may predict aggressive prostate cancer as a biomarker," said lead investigator Dr. Adam Murphy, an assistant professor of urology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine urologist. "Men with dark skin, low vitamin D intake or low sun exposure should be tested for vitamin D deficiency when they are diagnosed with an elevated PSA or prostate cancer. Then a deficiency should be corrected with supplements."

[HuckleB]

5. None of those studies show much other than noise.

You would know that, if you read the OP.

[womanofthehills]

6. I trust nothing from the link "sciencebasedmedicine"

we all know that is run by the pharma shill David Gorski.