Megadoses of Vitamin D have no effect... - Advanced Prostate...

Advanced Prostate Cancer
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Megadoses of Vitamin D have no effect on prostate (or any other) cancer

Tall_Allen
Tall_Allen

A new randomized clinical trial finally puts to bed the question of whether taking large doses of Vitamin D has any benefit in the incidence or progression of prostate cancer. At least with over 3 years of follow up, it did not.

pcnrv.blogspot.com/2018/07/...

They previously proved it has no effect on cardiovascular risk. Other studies have failed to show a benefit in bone mineral density among people at risk for osteoporosis (Men on ADT and post-menopausal women).

50 Replies
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"Vitamin D3 was initially given as one 100,000 iu pill, followed by 200,000 iu monthly pills"

That seems like some pretty unnatural dosing.

Not in the same league as moderate dialy dosing off someone with low levels of vitamin D.

But it is still cautionary about taking things to extremes without good evidence. There are probably lots of instances where a lot of a good thing is not helpful or is even counterproductive.

Thanks Tall for the data. What hit me the most in the study was this: "It should be remembered that Vitamin D is a steroidal hormone (like testosterone, estrogen, progesterone, and cortisol) and there are receptors for it on virtually all cells, healthy and cancerous."

Thanks again.

my oncologist (finally) has made a dietary/supplement recommendation other than "nothing"....and that was to take a Calcium with D3 supplement. **I just checked and my calcium on latest tests is in very good normal range. I'm assuming the lower dose that I am taking could perhaps be beneficial? They did note a new spot on my pelvic bone area...and are putting me on Xgeva also....?

~~John

Calcium supplements have been implicated in aggressive prostate cancer.

Thanks...and I am one of those lucky ones😔

gregg57
gregg57
in reply to Tall_Allen

Can you please provide a link to additonal information on that? I'm interested in learning more. Thanks.

mcp1941
mcp1941
in reply to Tall_Allen

My MO just added calcium supplements for osteopenia. Can you cite the source for aggressive PC?

Did not see the links. Please excuse me.

Mormon1
Mormon1
in reply to Tall_Allen

implicated? details please.

Tall_Allen
Tall_Allen
in reply to Mormon1

Read the links.

My GP recommends 50% of daily requirements come from a calcium citrate supplement for my osteopenia. So, what source is there to support my bone deficiency? I have met to the bone. Thank you.

I think canned salmon, herring, anchovies, etc. is the best source of dietary calcium because it has little bones that are made of the same mineral (apatite) that our bones are made of. Did you discuss using a bisphosphonate or using an estrogen patch (with tamoxifen)?

Thank you. I'll check with oncologist. I regularly eat sardines w/bones and canned salmon.

I eat a can of sardines and avocado on toast every morning just because I love them... good to know they are good for you too

Thx Tall_Allen

Thanks so much Tall Allen....finally can put this subject to an end!!

Woud you recommend any level of Vit D for someone with pCa? We are always looking to eliminate pills.

When we lived in MN (little sun) hubby tested low Vit D and was put on 10k for awhile. He has used 2k now for years but no calcium.

We learned the hard way when too much calcium almost killed my Mother.

Thx TA

Why would you take ANY drug (whether available OTC or by Rx) that has neither been proven to be safe or effective? He should have his plasma levels of Vitamin D checked. If below 20 ng/ml, he can supplement, otherwise he is fine without it.

Only taking because it tested low and was prescribed. If I recall, Vit D was all the rage at the time but we will request a blood test next visit. Meanwhile, I pulled it.

A bit off subject but he also takes daily (all prescribed) baby aspirin, B12 1500, carotene complex which is Vit A 3000 mcg with 6 mg food carotenoids blend.

Any opinions on those? Appreciate it.

It's hard to argue against baby aspirin. As for the others - what is he taking them for? If he has a deficiency, it might make sense.

The CARET trial found that increased intake of beta-carotene and Vitamin A among people at high risk for lung cancer actually INCREASED the risk of lung cancer by 28%, increased the risk of death by 17%, and had a higher risk of cardiovascular disease mortality.

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

As with the SELECT trial on Vitamin E and Selenium, we learned that observational studies cannot be relied upon, and that cancer biochemistry is much more complex than we thought.

mjbach
mjbach
in reply to Tall_Allen

I think hubby’s internist added the carotene when my husband complained of memory problems.

Now he has been put on donepezil by his neurologist. His pCa MO suggested stopping/withholding Xtandi to see if there are cognitive improvements.

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rococo
rococo
in reply to Hidden

Same with me except for the calcium. Be careful, they add calcium to so many foods orange juice cerial almond and soy milk to name a few. Rocco

You are aware that the study you cited was in post-menopausal women and had nothing to do with prostate cancer? Here's what the authors say about that study:

"Participants received vitamin D alone rather than with

calcium. It is possible that both medications, acting separately

or synergistically, had a greater influence than vitamin

D alone, although a reduction in cancer incidence was not seen

in theWomen’s Health Initiative which also gave both supplements.

"The cancer profile in the ViDA study had a much

larger proportion of cases with melanoma (33%) (Table 2)

compared with the Nebraska study (6%), although analyses

restricted to nonskin cancer produced a similar null result.

Although I didn't have PC symptoms I did have chronic D deficiency noticed for two years prior to diagnosis. After the DX started taking 5,000 IU daily for three months and it brought level back to the norm. After that reduced it to 2,000 IU by the mineral metabolism specialist recommendation to support calcium absorption. I've never thought anyone would take it in hundred thousands IUs though...

Tall_Allen
Tall_Allen
in reply to henukit

100,000 IU per month is equivalent to a daily average of 3,333 IU per day. Vitamin D is stored in fat and the liver. The researchers wanted to give enough to have a significant impact on blood levels, and it did.

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Tall_Allen
Tall_Allen
in reply to Hidden

There is no evidence that Vitamin D is more greatly absorbed with a high fat meal. In fact, absorption is better with a low fat meal. But absorption rates do not affect the plasma vitamin D levels:

onlinelibrary.wiley.com/doi...

It is STORED in fat and the liver so a big dose stays in the body for use as needed. That's why it doesn't matter if you take a bigger dose less frequently or a smaller dose more frequently. They felt that they would get better compliance with 1 pill per month, and they did. They randomly did blood tests on men in the study and found that serum Vitamin D blood levels consistently increased by at least 20 ng/ml.

I find this article of questionable value. First the high/infrequent doses, second there seems to be no baseline data on participants' Vit d (and calcium) levels, and third, it's in New Zealand which is at best a temperate climate (I would be more apt to call it almost sub-tropical) where Vit d deficiency is not expected.

Tall_Allen
Tall_Allen
in reply to herb1

I discussed their rationale for high/infrequent doses above - it really should not matter for Vitamin D, but if you believe it does, you are free to ignore the evidence. The baseline mean serum Vitamin D was 25.5 ng/ml in the treatment group and 25.2 ng/ml in the control group. The baseline mean serum calcium was 9.2 mg/dl in both groups. So it was very similar to US levels for this age group.

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Tall_Allen
Tall_Allen
in reply to Hidden

If you have a glass full of sunshine, is it full or empty? ;-)

j-o-h-n
j-o-h-n
in reply to Hidden

Depends if there's a full or half moon.

Good Luck and Good Health.

j-o-h-n Monday 07/23/2018 4:33 PM EDT

HI WHAT DO YOU SUGGEST TO TAKE IF I AM N MIDDLE OF RADIATION WITH ADT THANKS

Why are you taking Vitamin D?

YES MY DOCTOR TOLD ME TO TAKE CALCIUM AND D . PLEASE TELL ME ANYTHING THAT WOULD HELP ME WITH WHAT I AM GOING THRU AND WHAT I SHOULD DO THANKS A LOT

Mormon1
Mormon1
in reply to ricefarmer

Please look into taking vitamin K2 with D3 otherwise the calcium will go to the arteries and not the bones where you need it. My naturapath suggested it. I asked my pharmacist or never heard of K2. She called me the next day and said after googling there have been reputable studies verifying the goodness in adding K2 to my D3. I also take calcium. My prostate c spread to rib bone I take lupron and xgeva. since April. Psa of 11,000 now .4

Did your doctor say why he was telling you to take calcium and D? Perhaps your blood levels are low. (Please turn off your caps lock)

Dino24
Dino24
in reply to Tall_Allen

I was given similar instructions from my urologist. He said the calcium was for bone metastasis. My vitamin D level was a bit low and wanted to raise it.

no he just told me to take the two of them please help thans

You should ask him this question - I have no idea why he told you to take them.

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Tall_Allen
Tall_Allen
in reply to Hidden

In fact, several OBSERVATIONAL studies showed an association (see the first paragraph of my blog). Countering that, several observational studies showed a negative effect on survival, for example:

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

And several observational showed no effect, for example:

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

That's why we do RANDOMIZED clinical trials (RCT) - to find out once and for all exactly what the relationship is. This RCT proved there is no relationship.

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Tall_Allen
Tall_Allen
in reply to Hidden

You would have to understand "levels of evidence," which all doctors, professional orgs, and medical journals subscribe to. I encourage you to learn about it. A well-done RCT like this one settles the question and trumps all previous observational studies.

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Tall_Allen
Tall_Allen
in reply to Hidden

If you understood levels of evidence, you could not make such a statement. It directly contradicts it. The "scientific community" has now proven no benefit beyond a doubt. You are free to follow your hunches, but the evidence does not support you.

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