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Reduced cancer mortality with daily Vitamin D intake

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Re: Reduced cancer mortality with daily Vitamin D intake

#221

Post by anonymouskimmer »

throwaway646465 wrote: post #147
anonymouskimmer wrote: post #77

Earlier quoted context omitted.

The two signs bracketing the summer months (I presume this was in the northern hemisphere?). That's a potentially interesting finding. > inappropriate subgroup analysis No subgroup is inappropriate unless you know all of the values of all of the parameters. But sure, the intent they tried to demonstrate (take all sub-group analyses with a grain of salt) is a good thing to remember. Edit: To whoever downvoted me, time…

I think you got downvotes because you misunderstood what people were taking umbrage with in the first example. It’s not that birth time can never have real effects. It’s that if you keep rolling a die long enough, eventually you’ll hit a “statically unlikely” event like rolling 4 fives in a row or hitting 1 2 3 4 in order. Extraneous sub group analysis are like rolling the die again. Say you’re searching for a p-valu…

This is what follow up studies are for. To separate the wheat from the chaff. Don't separate before. See my rant below as to why I think pre-hoc decisions on analysis is a bad idea: https://news.ycombinator.com/item?id=35883276

At the very least, I'd like to see people say in advance which parameters they are interested in. That sort of thing is fine and important to avoid un-backed p-hacking. But for researchers who come after, for their sake, if you are not publishing the entire data so that they can reanalyze it de novo, please do as much analysis as possible (and record as many parameters as possible), if only in the supplementary data.

Science can only build on previous science if the authors of that previous science allow it to happen.

Re: Reduced cancer mortality with daily Vitamin D intake

#222

Post by anonymouskimmer »

9935c101ab17a66 wrote: post #204
anonymouskimmer wrote: post #77

Earlier quoted context omitted.

The two signs bracketing the summer months (I presume this was in the northern hemisphere?). That's a potentially interesting finding. > inappropriate subgroup analysis No subgroup is inappropriate unless you know all of the values of all of the parameters. But sure, the intent they tried to demonstrate (take all sub-group analyses with a grain of salt) is a good thing to remember. Edit: To whoever downvoted me, time…

I’m not a stats expert, but it seems blatantly obvious that subgroup selection could be inherently problematic because how do you choose the groups in an effective and responsible way? I mean, just the statement > no subgroup is inappropriate unless you know all the values of all the parameters seems implausible and unlikely. In the one stats class I took, we talked a lot about how selection bias was a huge concern.…

I just ranted to the top two commenters so I'll keep this response brief.

Say in advance which parameters and subgroups you, as a researcher, care about in terms of significance. And keep your conclusions and discussions focused on the results for those groups. Report all of the other stuff, whether p-significant, or not, as supplementary data.

Hopefully, yours is not the only study that will use your data. Don't limit future researchers to your hypotheses.

Re: Reduced cancer mortality with daily Vitamin D intake

#223

Post by anonymouskimmer »

bsder wrote: post #156
anonymouskimmer wrote: post #77

Earlier quoted context omitted.

The two signs bracketing the summer months (I presume this was in the northern hemisphere?). That's a potentially interesting finding. > inappropriate subgroup analysis No subgroup is inappropriate unless you know all of the values of all of the parameters. But sure, the intent they tried to demonstrate (take all sub-group analyses with a grain of salt) is a good thing to remember. Edit: To whoever downvoted me, time…

Your understanding of significance is flawed, and there is an XKCD for that: https://xkcd.com/882/

No, read my responses to the other commenters above you, who at least made arguments and didn't post a strawman, if you want to know why I believe you are wrong.

Re: Reduced cancer mortality with daily Vitamin D intake

#224

Post by agumonkey »

9935c101ab17a66 wrote: post #203
agumonkey wrote: post #162

Earlier quoted context omitted.

This is the issue raised by comments like the one above. We understand that evidence based medicine handles statistical averages very well. But if you fall out of that, all you're left with is snake oil salesmen. There's a need for an intermediate layer of evidence yet "taylored" (and not kidney-costing if possible).

Ya, but I think most good doctors operate with a balance of probabilities framework. Yah, there may not be conclusive evidence showing it’s widely effective, but based on this case, it’s obvious the person isn’t getting enough sunlight, and they communicated that to the doctor, and so why not do a trial of something like vitamin d? It’s widely studied, has very few serious downsides, and is cheap.

Doctors themselves exist in distributions, from very interested to not that much, from "motivated at that time" to "i have more pressing problems". Very often you get bounced for tiny reasons.

Re: Reduced cancer mortality with daily Vitamin D intake

#225

Post by dcow »

chii wrote: post #219
dcow wrote: post #202

Earlier quoted context omitted.

I'm not saying they key to good health is a big secret. I'm saying we're bad as a society or as human beings at objectively tracking this stuff and correcting negative trends often before it's too late. I've experimented with my body and nutrition a lot, with noticeable outcomes. You can't eat and know the next day that what you ate had too much refined sugar, or that it was organic and lacked toxins, just be how you…

> So, again, why would more open access to baseline metabolic metrics be a bad thing? not a bad thing if you considered it in isolation for a single individual. But for an entire society? The cost of doing so might be quite high, even if there's an economy of scale efficiency improvement for such large amount of testing/diagnostics. The recommended regime of diet, exercise and such, are a solution for most people tha…

So it’s “normal” for essentially half of all people to do regular bloodwork for significant phases of their lives. And old people and sex workers and there are more examples than I think you realize where people have blood drawn on the regular. I’m not sure you really have the scale dialed in. Either way, my example is most certainly a non-sequitur, we agree, because it’s an example, not a conclusion (8

To be clear, I’m advocating for a solution that’s more like doing a full metabolic panel every year, so you can catch people with Vitamin D deficiency. And/or an improved approach/UX surrounding managing patient case flows. I mean tracking tasks through workflow states is a very solved problem. To my knowledge hospitals don’t employ any such methodology.

Re: Reduced cancer mortality with daily Vitamin D intake

#226

Post by barelycompetent »

hombre_fatal wrote: post #191
dcow wrote: post #103

Earlier quoted context omitted.

This (among other things) makes me wonder why we don't have better metrics and monitoring solutions for the human body. Your option is anecdotal self-diagnosis, or a full blood panel after seeing a doctor and convincing them that you need to be tested. It seems there's room for a product that monitors your health and sends you notifications when you need to address any metrics that are falling out of normal tolerance…

You don’t have any wellness centers or clinics around you that offer blood tests? A full panel costs $80–100 but its not expensive for something you can do every few months to make sure you’re in good health. No need to convince a doctor.

In certain states the law forbids the unwashed masses from having their own blood tested (a doctor must order the blood test). Land of the free!

See (7) and (8) of https://malegislature.gov/Laws/GeneralLaws/PartI/TitleXVI/Ch...

Re: Reduced cancer mortality with daily Vitamin D intake

#227

Post by hattmall »

scottlamb wrote: post #144
hattmall wrote: post #82

Earlier quoted context omitted.

Sardines are good, I love them, but they definitely smell strongly and so will you if you eat them frequently. I wonder if there anything similar without the smell? Honestly for the reasons you listed though sardines are kind of a super food imo.

> Sardines are good, I love them, but they definitely smell strongly and so will you if you eat them frequently. Not sure I agree. It might help that I buy the smaller sardines (as mentioned above) and combine them with acid. I just did a search and both of those things were recommended as ways to reduce odor. I also generally eat them at room temp rather than cooking them, which I'm sure makes a big difference in th…

I never actually seen the tiny two layered kind. I just buy the cheap ones at walmart for like 80c a can, and it seems like it's the midsection of a fish about 4 per can. I definitely don't cook them, assumed they were cooked. Do you have a link to the small ones?

I like canned salmon as well, much less smell for sure but I figured it wasn't as healthy because of pollutants. Never tried mackerel. Found a chart and looks like, mackerel, salmon, herring, and sardines are all about the same. I've had the herring and it was good and similar price to sardines.

Re: Reduced cancer mortality with daily Vitamin D intake

#228

Post by mrtweetyhack »

francisofascii wrote: post #83
alejohausner wrote: post #54

The global distribution of many types of cancer is strongly related to latitude. The farther you are from the equator, the higher the rate of disease. The more sun you get, the less cancer. It's hard not to infer that sun exposure and thus synthesis of vitamin D helps prevent many cancers. We've been urged to avoid sun exposure because it can cause skin cancer. But those cancers are squamous and basal cell carcinomas…

Also sunlight during the day helps with melatonin synthesis at night, leading to better sleep, leading to less cancer.

[dead]

Re: Reduced cancer mortality with daily Vitamin D intake

#229

Post by scottlamb »

hattmall wrote: post #227
scottlamb wrote: post #144

Earlier quoted context omitted.

> Sardines are good, I love them, but they definitely smell strongly and so will you if you eat them frequently. Not sure I agree. It might help that I buy the smaller sardines (as mentioned above) and combine them with acid. I just did a search and both of those things were recommended as ways to reduce odor. I also generally eat them at room temp rather than cooking them, which I'm sure makes a big difference in th…

I never actually seen the tiny two layered kind. I just buy the cheap ones at walmart for like 80c a can, and it seems like it's the midsection of a fish about 4 per can. I definitely don't cook them, assumed they were cooked. Do you have a link to the small ones? I like canned salmon as well, much less smell for sure but I figured it wasn't as healthy because of pollutants. Never tried mackerel. Found a chart and lo…

I buy these: https://www.kingoscar.com/product/brisling-sardines-in-extra... They're not the cheapest sardine option; definitely not $0.80/can. But I have the money and really like them. I think the Tiny Tots-branded ones are identical (just different packaging). https://www.kingoscar.com/product/tiny-tots-brisling-sardine...

There are also some fish meal combo tins (salad toppers, really) I like, such as these: https://freshemeals.com/ My favorite is the Moroccan Tagine salmon. They're on clearance at my local grocery store for 50% off so I bought a few dozen...

iirc a physician advised my then-pregnant wife to have salmon at least twice a week, vs. the common recommendation to have tuna at most once a week.

Re: Reduced cancer mortality with daily Vitamin D intake

#230

Post by BeetleB »

kadoban wrote: post #217
BeetleB wrote: post #211

Earlier quoted context omitted.

> but based on this case, it’s obvious the person isn’t getting enough sunlight, and they communicated that to the doctor, and so why not do a trial of something like vitamin d? Can we get to the specifics? How would you propose the doctor do it? Let's say the doctor prescribes a certain dosage per day. How will the doctor know it is helping this particular patient? How long should the trial continue before he sees r…

> Let's say the doctor prescribes a certain dosage per day. How will the doctor know it is helping this particular patient? Check on them in X weeks and see if they're improved, and maybe measure blood levels just to get some objective measurement going. Doesn't seem too terribly hard. I think I'm missing the issue.

The issue is that for most issues where people claim Vitamin D helps, X is very large (several years). If your goal is cancer prevention, this approach is virtually useless unless done in large groups.

Other than bone issues, I don't think Vitamin D works for anyone in the short term. For a few people, they see improvements in mood within a few weeks or months. Most of these few people regress afterwords even with Vitamin D intake (i.e. the improvement was just the usual noise variation).

I have my own set of chronic issues, and there is no shortage of ideas on how to help: Diet, exercise, vitamins, etc. The way I've maintained my sanity is to ask the following question:

"OK, if I go with this treatment regimen, how will I know it is not working?"

Most advocates simply don't have an answer. If it's vitamins, they'll simply shift to a different dosage, a different vitamin, or pull out the new paper of the week saying how vitamin X is only useful in combination with mineral Y (you can see plenty of that in this submission). By the time you give that a try, another idea will come up.

There will be no way they will believe the solution is not vitamins.

If it's exercise, it will always be "You're probably doing it wrong" coupled with "You need to ensure you have the proper diet". When you get to specifics, they'll pull out 20 variables that could impact your exercise regimen. You can't reasonably try 2^20 combinations, let alone 20.

There will be no way they will believe the solution is not exercise.

Same goes with diet. Must be the sugar. Or too many carbs. Not enough protein. Too much protein. Or the lack of Omega-3.

There will be no way they will believe the solution is not diet.

I'm all for trying, and I do try different things. The reason I go to the doctor is to get an expert and informed opinion. If his opinion is "the data on Vitamin D is poor", I want him to state that.

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