Dietary supplements shown to increase cancer risk if taken in excess

Dietary supplements shown to increase cancer risk
Tim Byers, M.D., M.P.H. Credit: CU Cancer Center

While dietary supplements may be advertised to promote health, a forum at the American Association for Cancer Research (AACR) Annual Meeting 2015 by University of Colorado Cancer Center investigator Tim Byers, MD, MPH, describes research showing that over-the-counter supplements may actually increase cancer risk if taken in excess of the recommended daily amount.

"We are not sure why this is happening at the but evidence shows that people who take more dietary supplements than needed tend to have a higher risk of developing ," explains Byers, associate director for and control at the CU Cancer Center.

The line of research started 20 years ago with the observation that people who ate more fruits and vegetables tended to have less cancer. Researchers including Byers wanted to see if taking extra vitamins and minerals would reduce even further.

"When we first tested dietary supplements in animal models we found that the results were promising," says Byers. "Eventually we were able to move on to the human populations. We studied thousands of patients for ten years who were taking and placebos."

The results were not what they expected.

"We found that the supplements were actually not beneficial for their health. In fact, some people actually got more cancer while on the vitamins," explains Byers.

One trial exploring the effects of beta-keratin supplements showed that taking more than the recommended dosage increased the risk for developing both lung cancer and heart disease by 20 percent. Folic acid, which was thought to help reduce the number of polyps in a colon, actually increased the number in another trial.

"This is not to say that people need to be afraid of taking vitamins and minerals," says Byers. "If taken at the correct dosage, multivitamins can be good for you. But there is no substitute for good, nutritional food."

Byers says that people can get the daily recommended doses of vitamins and minerals in their diets by eating healthy meal and that many adults who take vitamin supplements may not need them.

"At the end of the day we have discovered that taking extra vitamins and minerals do more harm than good," says Byers.

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Dietary supplements increase cancer risk

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Apr 20, 2015
Multivitamins contain 100% RDA of several minerals which are toxic when present above 100% expectations in the blood:


If you have excess of these you get...drum roll...neuropathy!!!

That "take a multivitamin every day for men" thing is a LIE which is creating disease.

"one a day 50 plus"

Hey, diabetes? You take a multivitamin and you'll have neuropathy for more than one reason...

Good luck solving that with the medical community as it is.

Apr 20, 2015
Th is needs to be on television commercials, not just "health and fitness" shows. The doctors on those shows actually help promote some of the problems.

Apr 20, 2015
Re: "We are not sure why this is happening at the molecular level but evidence shows that people who take more dietary supplements than needed tend to have a higher risk of developing cancer"...

This is the clearest indication that I have ever seen. He admits that they know nothing about how nutrient-dependent RNA-directed DNA methylation and RNA-mediated amino acid substitutions link the biophysically constrained chemistry of protein folding to health and/or pathology via conserved molecular mechanisms in species from microbes to man.

See for comparison: Nutrient-dependent pheromone-controlled ecological adaptations: from atoms to ecosystems http://figshare.c...s/994281

Apr 20, 2015
Same dude 2 years ago, the same article: http://medicalxpr...cer.html

And so, Byers says. "My conclusion is that taking high doses of any particular nutrient is more likely to be a bad thing than a good thing."

The man is onto something.

Apr 20, 2015
Urrrr the reason IS KNOWN!!!! The mistake in the science was that experiments showed high levels of free radicals in cancer cells. This was incorrectly interpreted as free radicals cause cancer. NOW we know that the free radicals are actually PRODUCED by the cell and interpreted by other cells like a signalling system to indicate that the cell has malfunctioned and needs to be destroyed. So people that take high levels of anti-oxidants are actually muffling the free radical signalling system, and therefore allowing cancerous cells an opportunity to get a foot hold before being detected by the bodies immune system. This research was revealed just last year!!!
So it's a case of cause and effect was the wrong way around!!!!

You only need supplements if your doctor says you do!!!! Ohh and FFS don't overload on anti-oxidants, whatever you do!!!!!!

Apr 21, 2015
Bertrand Russell noticed how we were entering the age of linguistic precision.... imagine publishing an article saying that "drugs" cause cancer..... very unscientific, unprofessional.

What supplements were used? Turmeric? Broccoli extract? CLA? At what doses?

Likely this "research" was funded by the people who love a sick population: big pharma and the mainstream physicians...

Apr 21, 2015
Likely this "research" was funded by the people who love a sick population: big pharma and the mainstream physicians...

I'm not saying vitamins "caused" my illness, but that 100% of everything doesn't make sense now after the fact, when I realized how big a difference minerals make in the CBC. If you are outside the range on those minerals you get disease. You get kidney and liver failure, brain lesions, demyelinating diseases.

Right now the only thing I take for vitamins is D3 and Fish Oil extract, because I was told to take that by my doctor, and told to quit taking multi-vitamins, and DON'T drink tons water, but don't be afraid to drink water either.

Oh yeah, vitamin supplements actually cost more than prescription meds, because insurance doesn't cover them, or as much. Who do you think makes vitamin supplements? The same "big pharma" they have the same brand name sometimes.

If I had to pay out of pocket for my meds I'd be dead by now though.

Apr 21, 2015
They cause or enhance disease via promoting excess vitamin and mineral supplements on health shows like Dr. Oz and on television commercials, and then medicate the symptoms. It's a win-win situation.

"Tell your doctor you need blah, blah, blah..."


Your doctor is supposed to know how to diagnose your condition and tell you what you need, not the other way around. Though you should be informed.

If your doctor isn't as good as a veterinarian you should get a new one: new doctor.

"What seems to be the problem today?" - Doctor.

"Well, I'm sick, duh." Patient.


Do you know a veterinarian can test and diagnose a species/breed specific immunodeficiency disease in a single visit for a cat or dog who can't even describe their own symptoms?

A hospital needs a week to do the same test on a human being who can describe their symptoms...even if the doctor GUESSES correctly to run the right tests, because that's all many of them are doing.

Apr 21, 2015
It is to expected that an article on the dangers of dietary supplicants that JVK would link to his creationist bullshit.

Apr 22, 2015
Breast milk may alter behaviour of babies


Cell type differentiation is driven by viral microRNAs and the anti-entropic effects of nutrient-dependent microRNAs during all stages of development in all genera. The nutrient-dependent microRNAs are linked from nutrient uptake to RNA-mediated amino acid substitutions and cell type differentiation via the conserved molecular mechanisms of biophysically constrained protein folding.

Apr 26, 2015
JVK, you say that:
Cell type differentiation is driven by viral microRNAs ...

Your comment on viral microRNAs is not clear, JVK.
Do you claim viral microRNAs always beneficial, always harmful, or sometimes harmful and sometimes beneficial during 'all stages of development in all genera'?

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