
Dietary Supplement Use During Chemotherapy and Survival Outcomes of Patients - DanBC
https://ascopubs.org/doi/abs/10.1200/JCO.19.01203?journalCode=jco
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Tharkun
Don't have access to the full paper, but it seems like this study was based on
asking patients whether they were taking supplements, as opposed to
administering placebo/supplements and measuring the outcome. I would imagine
that the worse your cancer is, the more likely you are to try things like
supplements and whatnot. Did they manage to control for this?

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chiefalchemist
> "...were queried on their use of supplements at registration and during
> treatment..."

My concern as well. Self-reported is a red flag. Not necessarily fatal but it
obviously has an unpredictable affect on the data collected.

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fencepost
I suspect that if you're the type to take a bunch of individual vitamin
supplements then you know exactly what you're taking and how much, much more
so than if you're taking a multivitamin every morning washed down with your
coffee. There's also no reason to be lying about that to your doctor.

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saurik
The issue isn't that the patient is lying or doesn't know; the issue is that
the patient is taking supplements or not for a reason that is itself
correlated with the other side of our analysis: someone who is taking vitamins
might be more desperate, or might have more money (and so be living in very
different conditions or have less stress), or might be more likely to be doing
other random "maybe this will help?" things that are also random effects you
aren't asking about, or might be better at doing anything at all on a routine
(including other medical steps), or might be more able to get up and
walk/drive to take/buy vitamins, or might be experiencing a different level of
digestive effects from their chemotherapy. The reason why we use controlled
randomized trials is because they just fully solve this correlation analysis
issue.

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n8henrie
My impression is that lumped as a (extremely broad and diverse) whole that OTC
supplements, when studied rigorously in humans in vivo, have generally not
been found to be terribly effective for most maladies. Many have been often
found to have poor quality control, often adulterated with other substances,
provided in poorly bioavailable forms, or sometimes not actually containing
the substance they claim to contain.

As a whole they generally get a bad rap in medical school and among
physicians.

So I wonder if this study reflects a tendency of some patients to disregard or
be less adherent to the treatment plan recommended by their oncologists, who
seem unlikely to recommend dietary supplements that lack large supporting
RTCs.

Or perhaps, as mentioned, if they didn't properly control for severity of
disease, it is not uncommon for a provider to give a "sure, why not" when a
patient with severe / terminal disease is interested in an unconventional but
low cost and likely low harm intervention.

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dooglius
Well, antioxidants prevent damage to cells, so while that's normally helpful,
it directly works against things like Chemotherapy which are actively trying
to kill cells.

If I understand correctly, it looks like this is just evidence corroborating
the existing stance?

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nabla9
The problem with antioxidant supplements is that they don't necessarily work
well with metabolism.

After the antioxidant hype and supplement boom yielded no health benefits,
there have been multiple large studies showing no effect or negative effects.
They can remove benefits from physical exercise and increase cancer risk.
Vitamin C can remove benefits from exercise.

Overall the risks and benefits are small, but basically they are all useless.
If studies show benefits, it can be because some of the subjects suffered from
deficiency. You should take them only to treat vitamin deficiency or increased
need. Taking more and more of the good stuff is not automatically better.

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RandomInteger4
While all that may or may not be true, that is irrelevant to this study.

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kylek
Bad title (lumping together all supplements) when they are specifically
talking about antioxidant supplements.

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seveneightn9ne
They also looked at vitamin B, iron, and multivitamins.

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whb07
Peter Attia talks about this indirectly, where he’s been to some chemo floors
and observed patients taking “healthy” drinks and supplements that are mixed
as a milkshake of sugar and carbs.

Problem is a number of the cancer cells can only live on glucose. The other
pathways for energy are broken/nonexistent, and so consumption of sugary
drinks directly feeds fuel to these type of cells.

Strange how the field hasn’t connected the dots yet.

1\. Prove the cancer cells of X type can only feed on glucose

2\. If so, don’t ingest glucose.

Radical science here folks

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rubyfan
Do you have evidence beyond indirect second hand anecdotes that might support
your hypothesis?

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aiphex
This is not new information. And it's been shown to be efficacious. The
problem is patient adherence. Chemo is something that so long as the patient
shows up you can administer it and they can go back home. A glucose free diet
could only be adhered to on an in-patient basis. Which most patient /
healthcare systems cannot afford.

There have also been studies showing efficacy of a compound which down
regulates Glut1 in order to cut off glycolysis in cancer cells which rely
solely on it for energy production.

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whatshisface
> _A glucose free diet could only be adhered to on an in-patient basis._

That's not true, the Keto diet is a big fad and it only works if your diet is
basically glucose free.

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firethief
I have doubts about a couple of the assumptions implicit in this statement.

\- The "Keto" diet particularly works. Last time I checked, the research
suggested it worked about as well as any other elimination diet, or vanilla
CR.

\- The reason it works. Given that it works about as well as any other
elimination diet, it's probably important for practitioners to adhere
strictly, rather than continuing to consume the foods that made them fat; but
successfully avoiding carbohydrate intake enough to trigger some particular
level of ketosis is probably not a part of how it "works".

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whatshisface
Neither of those assumptions were implicit in the statement. The keto diet is
simply evidence that glucose elimination is possible for some people without
an inpatient treatment. The context of this discussion is glucose elimination
for cancer, not weight loss.

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firethief
(There is a fad that people attempt to do X) + (the observable result is
orthogonal to whether they successfully did X) => not very strong evidence
that doing X is achievable

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romaaeterna
A lot of statistical and methodological crimes being committed here.

"Patients... were queried on their use of supplements at registration and
during treatment".

Hazard ratios.

The blender approach of looking at all the reported vitamins at once, and
picking anything that looks significant.

People with the money to buy supplements take supplements...so this runs right
into the health/wealth correlation.

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buildbuildbuild
There are such varied supplements out there that this title feels vague. The
study focused on antioxidants.

Browse the top results of a search for “cancer supplements” and look at their
ingredients. You’ll find the majority were not included in this study.

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everfree
Seems just as likely that sicker patients tend to take more supplements.

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brooklyndude
I come from decades in the healthcare field (and published). Honestly? I would
take with a grain of salt pretty much anything i see published these days.

A. Friend 1, follows the MDs orders to the T. Is dead in 6 months.

B. Friend B. MDs you have 6 months to live. Get your affairs in order. It's
hopeless. Friend B? Fuck that, I feel great.

Friend B? Alive and running off to a yoga class. 14 years later. Healthy as
can B. As he says, Chinese medicine. Just do your homework.

Food for thought ... :-)

