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Regular use of Vitamin D supplement is associated with fewer melanoma cases

pubmed.ncbi.nlm.nih.gov

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Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#61

Post by mlinhares »

jmckib wrote: post #16
docflabby wrote: post #3

People who avoid the sun more likely to take vitamin D supplements?

I don’t have access to the full paper, but I would expect that they at least tried to control for sun exposure. In general, if you can think of an obvious confounding factor in about five seconds, then it’s a safe assumption that professional researchers thought of it too.

The study is based on a couple hundred people in a city in Finland, they could at least have tried to collect data on people closer to the tropics to hedge a bit. I doubt this has any validity ignoring such a basic confounding factor like living in a place that does have a lot of sun exposure.

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#63

Post by chrisco255 »

globular-toast wrote: post #26
cheald wrote: post #7

Earlier quoted context omitted.

A lot of people in the first world are heavily deficient in vitamin D, and deficiency is linked to a whole host of health issues and vulnerabilities. It's dirt cheap and essentially completely safe below toxicity levels (which are quite difficult to hit - I take 10,000 IU daily, and even with that my bloodwork shows me in the lower quartile of the normal range). Its metabolite is a steroidal hormone, so it's pretty o…

That seems like far too much, especially if you ever go outside. In the UK doctors recommend no more than 1,000 IU/day during the winter months. Any more than that is only if you are actually deficient. It seems really hard to get clear answers on it, though. People taking 10x the recommended dose of something seems strange. It makes me think it's being stored somewhere that isn't your blood. It's fat-soluble after a…

Vitamin D is a fat soluble vitamin, so of course it is being stored in fatty tissues in the body. Where else would it be stored? Your blood stream is not a storage mechanism but a transportation mechanism.

Daily Recommend Values for basic nutrients aren't the same as medicinal dosages. Nobody ever gets Daily Recommended Values for all the essential nutrients anyways, and many of them are regularly exceeded by a single multivitamin or dish. They're also somewhat arbitrarily defined. Like the food pyramid, you should take them with a grain of salt.

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#64

Post by thenerdhead »

hn_throwaway_99 wrote: post #59
thenerdhead wrote: post #56

Earlier quoted context omitted.

1. No, because the specifics change every week. One week you're deficient in fiber, the next Vitamin D. Look to the mainstream news or online articles for this ridiculousness. 2. Maybe consider looking at modern research. https://www.cancer.gov/research/key-initiatives/ras/ras-cent... > Nevermind that Pauling's vitamin C theories have been thoroughly disproven. Nothing in science is proven. Only re-evaluated.

The funny thing about the link that you give is that the hypothesis around intravenous Vitamin C is literally the exact opposite around Pauling's beliefs of oral vitamin C. That is, taken intravenously, Vitamin C generates free radicals like hydrogen peroxide that are particularly dangerous to cancer cells. This is the exact opposite of oral administration of Vitamin V where it acts as an antioxidant.

Maybe read his book so you can hear what he has to say about it rather than your interpretation of it.

Anyway, the article I linked summarizes it fine too:

> So why did the Pauling and Mayo Clinic trials have different results? There are at least two crucial differences. First, the Mayo Clinic trials abruptly stopped the ascorbate administration, switching to traditional chemotherapy, when the patient developed signs of tumor progression. Thus, the overall median time of vitamin C treatment under the Mayo Clinic trials was only 2.5 months, while the Pauling and Cameron trials treated patients for the duration of the entire study period or as long as 12 years. Secondly, the Mayo Clinic trials administered 10 g of daily ascorbate to patients only orally, while the Cameron and Pauling trials administered their vitamin C both orally and intravenously. This difference in the two dosage routes proved highly consequential.

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#65

Post by resoluteteeth »

mistrial9 wrote: post #6

I was told recently that US Doctors have lost their license over this topic; no idea if that is true.

I doubt it. Michael F. Holick is probably the biggest vitamin d proponent and he has gained notoriety for having received a lot of money from companies making vitamin d supplements, as well as having done some wild stuff, such as defending abusive parents in court on the theory that children's broken bones are a result of vitamin d deficiency:

> In one case of a child who had suffered broken bones in which Holick defended the accused parent, the child later went on to suffer severe brain injury, for which the parent has been indicted.

as well as this interesting theory:

> Holick has speculated that the dinosaurs may have died of rickets and osteomalacia caused by a lack of vitamin D in reduced sunlight

https://en.wikipedia.org/wiki/Michael_F._Holick

and the only repercussion he has faced was the place he works not allowing him to treat children anymore.

If he hasn't had his medical license revoked I doubt any doctor simply recommending vitamin d would have theirs revoked.

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#66

Post by KennyBlanken »

kixiQu wrote: post #54
jmckib wrote: post #16

Earlier quoted context omitted.

I don’t have access to the full paper, but I would expect that they at least tried to control for sun exposure. In general, if you can think of an obvious confounding factor in about five seconds, then it’s a safe assumption that professional researchers thought of it too.

Or, at least, a safer assumption: it's worth checking to see what they said about it before publicly speculating. And indeed, it seems they did survey for sun exposure and include it in their analysis, and they caveat a lot of their references to other work in their introduction noting where other studies didn't . https://www.naturalhealthresearch.org/wp-content/uploads/202...

> Or, at least, a safer assumption: it's worth checking to see what they said about it before publicly speculating.

This would immediately kill about half of the comments on any research article posted to HN.

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#67

Post by NavinF »

globular-toast wrote: post #26
cheald wrote: post #7

Earlier quoted context omitted.

A lot of people in the first world are heavily deficient in vitamin D, and deficiency is linked to a whole host of health issues and vulnerabilities. It's dirt cheap and essentially completely safe below toxicity levels (which are quite difficult to hit - I take 10,000 IU daily, and even with that my bloodwork shows me in the lower quartile of the normal range). Its metabolite is a steroidal hormone, so it's pretty o…

That seems like far too much, especially if you ever go outside. In the UK doctors recommend no more than 1,000 IU/day during the winter months. Any more than that is only if you are actually deficient. It seems really hard to get clear answers on it, though. People taking 10x the recommended dose of something seems strange. It makes me think it's being stored somewhere that isn't your blood. It's fat-soluble after a…

> People taking 10x the recommended dose of something seems strange

Not really. If your blood work shows shows you're low, you'll get a prescription for a very high dose. 100x is normal for some vitamins

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#68

Post by Iulioh »

Calavar wrote: post #43
jmckib wrote: post #16

Earlier quoted context omitted.

I don’t have access to the full paper, but I would expect that they at least tried to control for sun exposure. In general, if you can think of an obvious confounding factor in about five seconds, then it’s a safe assumption that professional researchers thought of it too.

> In general, if you can think of an obvious confounding factor in about five seconds, then it’s a safe assumption that professional researchers thought of it too. I work in academic medicine. I read a lot of papers. This is not at all a given in my experience, except maybe in the tippy top journals (Nature, NEJM). When in doubt, read the paper, see if they mention the confounder you thought of.

>it’s a safe assumption that professional researchers thought of it too.

It's a safe assumption that they though of it

BUT

Testing for it and getting useful data of something like a survey is a different story.

For example for a thing like that a survey could do more harm than good if the principles aren't really strict.

It wouldn't surprise me that some researchers could have just ignored not measurable data like that for the analysis. (staring if ofc)

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#69

Post by dwighttk »

kixiQu wrote: post #54
jmckib wrote: post #16

Earlier quoted context omitted.

I don’t have access to the full paper, but I would expect that they at least tried to control for sun exposure. In general, if you can think of an obvious confounding factor in about five seconds, then it’s a safe assumption that professional researchers thought of it too.

Or, at least, a safer assumption: it's worth checking to see what they said about it before publicly speculating. And indeed, it seems they did survey for sun exposure and include it in their analysis, and they caveat a lot of their references to other work in their introduction noting where other studies didn't . https://www.naturalhealthresearch.org/wp-content/uploads/202...

or publicly speculate and let a commenter who is more worried about checking check for you

Re: Regular use of Vitamin D supplement is associated with fewer melanoma cases

#70

Post by kstrauser »

lowmagnet wrote: post #31
kstrauser wrote: post #27

Earlier quoted context omitted.

Also, ask your doctor to get yours tested! A couple years ago, my D was on the low end (31.7ng/mL; 30-100 is normal). I've been taking 5000IU of D3 since then, and a lab last month had me at 59.1. That seems to be about the perfect dose for me, and it's dirt cheap.

I just take D3 50K a week, what a doctor once recommended when I was tested and found almost with something like 6 ng/dL of D in my system. BTW, did they tell you to back off or cut your dose? at 59 ng/mL you're in the danger zone.

They said keep going. 59 is where NIH says you want it to be. From https://ods.od.nih.gov/factsheets/VitaminD-Consumer/ :

* Levels of 50 nmol/L (20 ng/mL) or above are adequate for most people for bone and overall health.

* Levels below 30 nmol/L (12 ng/mL) are too low and might weaken your bones and affect your health.

* Levels above 125 nmol/L (50 ng/mL) are too high and might cause health problems.

Although there is a weird confusion of units. The results I'm looking at right now use ng/mL, but lists the numbers for nmol/L. The report includes a graph like:

30 ng/mL --- 59.1 ng/mL (in range) --- 100 ng/mL

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