NKinney said...
justwondering said...
Any dosages considered toxic?
Yes, mega-doses of Vitamin D is associated with increased advanced prostate cancer. At the same time, low doses of Vitamin D are also associated with increased diagnosis of PC.
Low levels of Vitamin D has been associated with numerous different issues, so there's two things you might want to consider.
Go to your doctor and ask for a Vitamin D level test. If you are low, discuss a doctor-monitored short-term regimen of Vit D mega-dosing. Absolutely do not do this on your own, but many men here have followed this same route...doctor-monitored, doctor-controlled.
Or, my own doctor indicated to me that even without testing, a low dose of 2000 IU of Vitamin D won't hurt and will more likely help.
This is an excellent topic for YOU to raise with YOUR primary care physician.JW, can't really say regarding the tomato products, but if you doa search here at HWPC, you will find numerous threads where the subject of Vitamin D supplementation (and or getting more sun exposure which can easily generate 10,000 iu) is debated quite robustly. In fact you will find a very recent thread I started reporting yet another study- with the famous PC surgeon Dr. Catalona one of the studies authors- showing an association of lower blood vitamin D levels with PC, and particularly with the more aggressive forms of the disease( with severe deficiency being associated with about
FOUR times higher rate of the more aggressive PCs.)
As far as megadosing, I'd say it depends on what is meant by megadosing, considering less than an hour of sunshine can generate 10,000 units, which is a high dose indeed. I have seen studies that talk about
a "U" shaped curve, supposedly with high rates with low levels, lower rates with levels in the middle, and then PC rates increasing as you went up from that just right amount. But when I looked closely at those studies, I did not see that. I saw the lowest PC rates associated with the lowest levels of vit D, then increasing PC rates with the middle Vit D, then PC rates dropping again at the higher vit D rates. (but if memory serves, none of that applied to the more aggressive PC, which simply had lower rates of that associated with higher Vit D levels- but don't hold me to that until I check)
Then there were some follow up studies that indicated those odd findings might well have been due to selection bias. And when results were corrected for selection bias, they found nothing other than decreased PC with increasing vitamin D levels, but again, most especially less of the more aggressive. How could you get a selection bias? It is not unlikely that many men who already have undiagnosed PC, but are worried they might have it and/or are worried about
other health issues, supplement with Vitamin D. If a significant % of men do that, then guess what is going to show up in the blood of men diagnosed with PC? Yep, higher vitamin D levels, unless the researchers correct for that.
I am going by memory here, don't have time to try and look up all of these studies. But you can find all of them discussed at length here on HWPC.
In my non-professional ( i.e. not a PC doc )opinion, testing and then getting enough sunshine and or vitamin D supplement to keep your blood levels at 30 ng or a bit higher is probably pretty safe, and may well be helpful. But as NKinney said, that is a very good thing to discuss with your doctor. Unfortunately, we are waiting, and waiting for many years now for the gold standard, solid, large scale randomized control studies to either prove help, harm or indifference one way or another. But we just keep on waiting.
BTW, for what it is worth, there is a poll done here( by me ) of folks who had their vit D blood levels checked at or near the time of their diagnosis with PC. Almost all had levels well less than 30 and the ones with aggressive PC almost all had very low levels of Vitamin D. I realize this could just be coincidence, and it is based on small numbers because very few folks have had their vitamin D levels checked, and some who have(like me) were already supplementing with Vitamin D before testing. But since my level was only 30 ng even supplementing with 2000 IU/day, I have to presume that most of my life, while my aggressive PC was percolating inside me, I was running a deficient level of Vitamin D.