Optimal D-3 level?

[LF27]

Is there consensus on what an optimal vitamin D-level should be to inhibit metastasis?

[Tall_Allen]

There really is no consensus, and the level of evidence is poor. Vitamin D serum levels below 20-30 ng/ml have sometimes been found to be associated with incidence of prostate cancer, although several studies contest that finding. Even moderately high serum Vitamin D levels have been found to be associated with increased risk of aggressive prostate cancer in some studies. Other studies have found no consistent association.

I haven't seen anything that suggests that it could inhibit metastases in men already diagnosed with PCa. I've only seen a mouse study that suggests it may start by inhibiting the incidence of PCa, but with continued use, after PCa already exists, may actually increase the rate of metastases:

ncbi.nlm.nih.gov/pmc/articl...

It is a steroidal hormone that has been found to be associated with increased testosterone levels. Maybe not what you want if you're on ADT.

ncbi.nlm.nih.gov/pmc/articl...

[BigRich in reply to Tall_Allen]

That was an eye opener re.Vitamin D. Thank you for the sited articles, especially the second article.

Rich

[jdm3 in reply to Tall_Allen]

Thanks for the information, as always.

You kinda just burst my bubble since I felt sure that higher doses of Vitamin D were good, or at least could not be harmful. Now I don't know. The data seem inconclusive, and suggest D is okay in "hormone-intact" mice, but perhaps not otherwise -- "may increase metastases" is not something I want to read about a supplement I take. Anyway, any information is better than no information. Thank you.

[Tall_Allen in reply to jdm3]

I believe that there is an ongoing randomized clinical trial, which would be definitive, but it will be years before we have results. I've found that on sites like this, people are wont to only quote evidence that supports their already-formed conclusions. Since I know others will quote the "pro" studies, here are a few of the 'con" studies on Vitamin D:

ncbi.nlm.nih.gov/pmc/articl...

academic.oup.com/jnci/artic...

cebp.aacrjournals.org/conte...

ncbi.nlm.nih.gov/pubmed/248...

ncbi.nlm.nih.gov/pmc/articl...

Steroid biochemistry is very complex. There are receptors on almost all cells that are upregulated or downregulated based on the amount in the serum. There are binding proteins that regulate what gets into cells. There are also enzymes that regulate their interconversion. Vitamin D at very high levels can actually pull calcium out of bone to increase the calcium serum level - not a desirable effect if bone mineral density is low due to ADT. If levels are low, I think we should be taking the minimum needed to keep it in the normal range, at least until there is better safety data available.

[pjoshea13 in reply to Tall_Allen]

You say:

"we should be taking the minimum needed to keep it in the normal range"

Wikipedia [1] [2]:

"A 2014 review concluded that the most advantageous serum levels for 25(OH)D for all outcomes appeared to be close to 30 ng/ml (75 nmol/L)."

Vitamin D Council:

"The Vitamin D Council makes a recommendation of 50 ng/ml"

Typically, as I recall, deficiency is defined as <20 ng/mL & insufficiency as 20-32 ng/mL. So I tend to view 32 ng/mL as the bottom of the sufficiency range.

But let's go with 30 ng/ml (75 nmol/L) as the absolute minimum.

From the first paper you cited:

"circulating levels of 25(OH)D greater than 37.5 nmol/L were associated with increased risk of aggressive prostate cancer, consistent with our results"

"37.5 nmol/L" is 15 ng/mL.

May I ask if you take cholecalciferol & what your "normal" target is?

You say:

"Vitamin D at very high levels can actually pull calcium out of bone to increase the calcium serum level"

Are you referring to 1,25-D, rather than 25-D?

-Patrick

[1] en.wikipedia.org/wiki/Vitam...

[2] ncbi.nlm.nih.gov/pubmed/252...

[3] vitamindcouncil.org/for-hea...

[4] ncbi.nlm.nih.gov/pmc/articl...

[Tall_Allen in reply to pjoshea13]

So the data suggests there is a relationship between Vitamin D levels and increased risk of aggressive cancers, even at relatively low levels. All the more reason to avoid supplementation.

My last serum test was 23 ng/ml. My PCP recommended supplementing with 10,000 iu/day. I told him he was crazy (I found a new PCP who makes recommendations based on evidence). I did take 400 iu/day for about a year, but after reading the following editorial and article, I decided that there was really little probability that increasing it would be advantageous. They write: "Serum 25-OH-D levels of 12 to 20 ng per mL (30 to 50 nmol per L) correlate to the vitamin D exposure necessary to maintain bone health. Individuals with levels less than 12 ng per mL are usually deficient in vitamin D, and 97.5% of individuals with levels higher than 20 ng per mL have adequate vitamin D intake."

aafp.org/afp/2018/0215/p254...

"LeFevre and LeFevre's review of the evidence for vitamin D screening and supplementation in adults in this issue of American Family Physician determined that these commonplace practices [Vitamin D supplementation] have virtually no established health benefits. The American Society for Clinical Pathology recommends against screening for vitamin D deficiency in the general population. The U.S. Preventive Services Task Force found insufficient evidence that vitamin D supplementation prevents cardiovascular disease, cancer, or fractures in community-dwelling adults. An umbrella review of more than 100 systematic reviews and meta-analyses of observational studies and randomized controlled trials found only a handful of “probable” relationships between serum vitamin D concentrations and clinical outcomes, and concluded that vitamin D supplementation does not increase bone mineral density or reduce the risk of fractures or falls in older adults."

aafp.org/afp/2018/0215/p226...

[pjoshea13]

A 2016 Swedish study [1], on a population not known for vitamin D sufficiency, reported:"

"We observed a trend toward a lower prostate-specific mortality with 25OHD >85 nmol/L in the unadjusted analysis. This became statistically significantly in the third quartile of 25OHD (85-102 nmol/L) compared to the first (<68 nmol/L), HR 0.54 ... when adjusting for age, time of inclusion, and BMI. The association was further strengthened when adjusted for age at diagnosis, Gleason score, and TNM classification with a HR in Q3 0.36 ..."

85-102 nmol/L is 34-41 ng/mL

-Patrick

[1] ncbi.nlm.nih.gov/pubmed/270...

[pjoshea13 in reply to pjoshea13]

Here's another [2].

"We assessed prediagnostic 25-hydroxyvitamin D [25(OH)D] levels in plasma, variation in vitamin D–related genes, and risk of lethal prostate cancer using a prospective case–control study nested within the Health Professionals Follow-up Study. We included 1260 men who were diagnosed with prostate cancer after providing a blood sample in 1993–1995 and 1331 control subjects. Men with prostate cancer were followed through March 2011 for lethal outcomes (n = 114)."

"Men with the highest quartile of plasma 25(OH)D levels had less than half the risk of lethal prostate cancer compared with men who were in the lowest quartile of plasma 25(OH)D levels, regardless of time from blood collection to diagnosis."

-Patrick

[2] ncbi.nlm.nih.gov/pmc/articl...

[FCoffey]

Yes, when you give huge doses to mice that are genetically engineered to develop prostate cancer - they get sick! Imagine that.

But when actual humans are tested, the men who have higher D levels are least likely to die of prostate cancer.

Mercola cites other research, and recommends 70-100 ng/ml for cancer patients. He recommends 50-70 for cancer prevention, but those of us in this group are rather beyond that point.

articles.mercola.com/sites/...

This article points out that "if you were in the sun nearly every day with large amounts of your skin exposed and not taking any oral vitamin D, your level would be around 100 ng/ml. " Prostate cancer is more common on northern latitudes, where sun exposure is low and seasonal, and vitamin D levels low.

articles.mercola.com/sites/...

Extrapolating mouse models to human dosage recommendations is foolish, irresponsible, and dangerous. The human studies demonstrate benefits from quite high levels of Vitamin D.

[j-o-h-n]

I wonder if Mickey takes vitamin D?

Good Luck and Good Health.

j-o-h-n Monday 06/04/2018 6:13 PM EDT

[leswell in reply to j-o-h-n]

Great image!

[LF27]

Thanks for the spirited discussion, all!

[leswell]

Yes, always enjoy a spirited discussion. Still, it gives one pause if taking Vit. D (10,000 IU).

Vitamin D is the ONLY supplement recommended by our MO—I think half that much though. Mrs. S

P.S. I’ll just switch to dandelion leaves and roots. Then we can argue about the safety of that. Free metformin is my primary interest at the moment.

P.P.S. Terribly sad about Neal-Snyder’s death recently. Such a smart and kind person who contributed much to such discussions—one on metformin as I recall.

[Litlerny]

More confused than ever. I’m not a lab mouse, but sometimes I feel like one. As a supplement to ADT, I’ve been taking Theralogix Prosteon for Bone Health (Google it) b.i.d. Every day for the past 3 years. It contains calcium, D3, K1, Mg, Strontium, and Boron. It was recommended by the urologist who gave me my Stage 4 oligometastatic PCa Dx in June, 2015. Both my family doc, and maybe more importantly, my Mayo Clinic M.O. are on board with my using it. I’m still hormone sensitive with an undetectable PSA, testosterone 7, and all other labs (other than slightly elevated glucose for which I take Metformin) are WNL. As of last year, my lone metastatic tumor to my inferior pubic ramus no longer lights up the PET scan and bone density is normal. I go back next month for my next scheduled scan. I’ll let you all know the results of that. Until then, and unless my M.O. tells me to stop, I’ll stick with the program.

[Break60]

My RO Recs 5000IU daily

[rocket09]

It is a natural vitamin from the sun that many people do not get enough of. Sun that is. I feel better when I get enough sun so that says it for me. I make sure to get enough D. Go with what your gut tells you , sun or no sun.

[abmicro]

According to Dr Charles Myers (when I saw him years ago), as you get older, your skin does not absorb much D anymore from the sun and D must be supplemented.

40 is a good level. That 40 level was also OK'd by my City of Hope oncologist, by cardiologist, and my endocrinologist, and from many articles I read. If you reach a level of 50, it is still OK and wont harm you, but 40 is perfect.

My level was 20 for many years and it resulted in osteoporosis with fractures by the time my age got to 45. (That was years before I had prostate cancer.) Anybody that says 20 OK is is full of crap. The other vitamins, calcium, and nutrients that help build strong bones can come from foods.

If you have a problem with stomach acid, avoid chewable acid reflux meds like Gaviscon because it can nullify any D suppliments you are taking or getting from food. Better to drink green juice than take those acid reflux meds.