The Supplement Causing Cancer Story is BS…
Dr. Tim Byers conducted a meta-analysis of two decades worth of research and concluded that a number of supplements actually made a person much more likely to develop certain types of cancer. He presented his research this past Monday, April 20th, 2015 at the annual meeting of the American Association for Cancer Research in Philadelphia. My opinion is this study is not new at all—and complete bullshit! (Oops…I can’t believe I just said that.)
Details of Dr. Byers’ view
Here is the link to the sensational news reports:
University of Colorado Cancer Center
In an interview with CBS Dr. Byers was quoted:
“There’s enough evidence along these lines that we should really consider better regulation of these nutritional supplements,” Byers told CBS News. “I think it’s time to step back and say there’s probably a safety issue.”
Well, is it true? Is there really enough research to show that consuming dietary supplements increase the risk of cancer?
My Take on Dietary Supplements Increasing the Risk of Cancer
This “latest news” on dietary supplements causing cancer is old, old news. In other words, what Dr. Byers did is rehash studies that began up to 30 years old, most of which we have spoken about ad nauseum like the SELECT study. So, why is Dr. Byers bringing up such old stuff again?
I don’t know. A cynic (and I can be one at times, I admit) would think he is paid by big pharma to bring the supplement industry down to its knees. Or he is simply anti-supplements and anti-natural medicine spokesperson like a few other doctors.
But no. Dr. Byers is a faculty member of the University of Colorado with interest in the role of nutrition and diet in cancer. Why would anyone write a paper that is not only unoriginal but as old as the Clinton administration?
The answer is simple: money. The more papers you publish in journals, the more publicity you get and the more likely you are to be able to secure grants to continue your investigations. And saying something counter intuitive like “supplements cause cancer” will always get a lot of media attention since we are talking about a nearly $30 billion dietary supplement industry.
You see, researchers are under an astronomical amount of pressure to publish and gain attention for their work, which in turn leads to more research grants – which in turn leads to more security and more appointments. Research scientists are burned out by this pressure to publish as often as possible. It’s publish or perish, as they say in the academic world.
Joeri K. Tijdink, MD, PhD, fellow at Free University Medical Center in Amsterdam, the Netherlands, has been quoted saying:
“If you’re a professor who has a lot of papers that have been published, you feel less burned out and less pressure. This is logical, because you’re more used to how the system works.”
By the way, confusion about dietary supplements is a major discussion at the CaPLESS Retreat (prostate cancer health retreat) since some supplements can potentially promote cancer.
Back to Dr. Byers and his Recent Analysis
Through his research, Byers found that people who took high doses of beta-carotene supplements had an increased risk for lung cancer. Again, none of this information is new. The connection between beta-carotene and lung cancer in smokers was published in the mid-1990s. I assume you can find concentrated beta-carotenes in some bottle somewhere, but integrative and naturopathic doctors have been using mixed carotenoids, which might have protective benefits unlike the concentrated form beta-carotene.
Dr. Byers: Men who took vitamin E had an elevated risk for prostate cancer.
Me: OK, are we seriously talking about SELECT again? This goes back to 2008. And besides, if you’ve been reading my blogs for a while you I have highlighted the flaws of SELECT.
But in case you are new to this, allow me to provide an summary:
SELECT was a prospective, randomized, double-blind, placebo-controlled clinical trial of selenium and vitamin E in healthy men who were at elevated risk of prostate cancer by virtue of age or African ancestry. Participants were randomized to receive daily oral doses of either:
- 200 micrograms selenium (in the form of SelenoMethionine) plus placebo,
- 400 milligrams dl-alpha-tocopherol vitamin E plus placebo,
- 200 micrograms selenium plus 400 milligrams dl-alpha-tocopherol,
- or two placebos.
The study was supposed to last 12 years, but after about 6 years SELECT was stopped following an interim analysis showing that it was unlikely that either selenium or vitamin E had any benefit for prostate cancer.
Further SELECT research showed a 17% increased risk of prostate cancer in those taking 400 of dl-alpha-tocopherol vitamin E and a 91% increased risk of high-grade cancer among men taking SelenoMethionine (selenium). All these men had high selenium status at baseline (Klein et al., 2011).
My take on SELECT
SELECT was a high powered (35,000 subjects), multi-centered ( more heterogeneity) , long-term (12-year) clinical study well funded (between $150 TO $300 million) clinical study.
Unfortunately, SELECT researchers, non of which have a background in nutrition science, by the way, lost an opportunity to see if using the right form of vitamin E and Selenium would have any benefit in preventing prostate cancer. In other words, we wasted a whole lot of tax payer money on this one.
What do I mean? The vitamin E used in SELECT was a synthetic form – dl-alpha-tocopherol. And the form of selenium used was selenomethionine not High Selenized Yeast (SelenoExcell. )
Why is this important? The reason the study SELECT became of interest is because the Alpha Tocopherol Beta Carotene (ATBC) study showed that dl-alpha-tocopherol reduced the risk of prostate cancer.
Oh, yeah. They used 50 units of the unnatural, dl-alpha-tocopherol Vitamin E.
For an unknown reason, researchers used 400 units in SELECT. That’s right – eight times the amount used in the ATBC study – the study that initiated interest. Also, natural vitamin E with high amounts of gamma-tocopherol is protective against prostate cancer. (Jiang et al. 2004). In the year 2000, John’s Hopkins looked at over 10,000 men, showing higher blood levels of alpha-tocopherol and gamma-tocopherol were each associated with a lower risk of developing prostate cancer, but the association with gamma-tocopherol was stronger than that of alpha-tocopherol. (Helzlsouer et al. 2000)
How about Selenium? Interest in selenium’s protective effects against prostate cancer came from the NPC trial, which showed a reduction in prostate cancer along with other forms of cancer. The problem? The NPC used High Selenized Yeast, SelenoExcell, which is more food-like and less concentrated compared to SELECT, which used 100% Selenomethionine. Selenium Yeast not only consist of selenomethionine but also contains a wide variety of organically bound selenium compounds like selenocysteine and methylselenocysteine, which very likely could have greater anti-carcinogenic activity than selenomethionine alone.
Recently, High Selenized Yeast, SelenoExcell was randomized to placebo and SeMet (200 mcg/day) administered for 9 months in 69 healthy men. Dr. Richie and his team noticed a reduction in biomarkers of oxidative stress relevant to prostate cancer following supplementation with High Selenized Yeast but not selenomethionine in healthy men. This study suggests that selenium-containing compounds other than selenomethionine may account for the decrease in oxidative stress. (Richie et al. 2014)
If this is not the GIGO effect I don’t know what is.
Other studies Byers reviewed indicated that many other supplements had no apparent impact on cancer risk—neither increasing nor decreasing it.
No apparent impact on cancer risk; Really? How come some of the studies I have compiled have shown the opposite?
Take for example a study of a dietary supplement formula consisting of broccoli , turmeric, pomegranate and green tea.
Researchers looked at 199 men, average age 74 years, with localized prostate cancer, 60% managed with primary active surveillance (AS) or 40% with watchful waiting (WW) following previous interventions, were randomised the botanical blend for 6 months.
PSA reflected underlying disease status as the percentage change in PSA was 10-fold lower in the men with and a disease shrinkage was noticed on MRI compared with disease progression no man taking the food supplement had disease progression with a stable PSA. This study would have had more impact if the follow-up would have had a biopsy. But who wants excess biopsies? And who would pay for that? Cost often makes supplement studies prohibitive when a lot of expensive testing is involved. HERE is a link to the study.
In the VITamins and Lifestyle (VITAL) study, which looked at over 35,000 subjects, the use of grapeseed supplements was associated with a 41% reduced risk of total prostate cancer.
Another meta-analysis of observational studies supports an association between higher calcium consumption and reduced breast cancer risk.
One meta-analysis found that higher calcium intake was associated with reduced colorectal cancer risk.
The Physicians’ Health Study, evaluating the impact on men using a regular multivitamin supplement demonstrated a modest 8% reduction in total cancer incidence in men taking a multivitamin. In addition, men with a history of cancer derived the most benefit from MVM supplementation, with a 27% lower incidence of new cancer compared to placebo.
The French randomized clinical trial Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) evaluated a supplement containing Vitamin C 120 mg, vitamin E 30 mg, beta-carotene 6 mg, selenium 100 µg, and zinc 20 mg. This supplement was associated with a 31% reduction in overall cancer and a 37% reduction in overall mortality in men but not in women (about 7.5 years).
A meta-analysis of 13 prospective European and North American cohort studies reported a decrease in risk of colon cancer among MVM supplement users compared with nonusers . MVM supplement use for 15 years was associated with a 75% reduction in colon cancer risk in the prospective Nurses’ Health Study (NHS) based on questionnaires completed by 88,756 female nurses in the United States.
But the better question is – why are dietary supplements studied like drugs when they are not drugs?
The scientific method is the approach used by the scientific community to assess if a pharmaceutical drug or a medical procedure has any effect on a particular disease. To control an experiment, you want to eliminate as many confounding factors an isolate the treatment as much as possible.
What do I mean?
If I want to know if drug A, a pill, can cure cancer, then I would set up a study where I recruit, say, 1000 people with cancer (any cancer, to keep it simple), randomly assign 500 to the drug and the other 500 to an indolent pill that looks like pill A but only contains sugar.
I would then follow both groups for as long as possible. The more subjects to study and the longer the study, the more valuable the data and the more clinical relevance it may have. Of course, this gets expensive. That’s why studies like this are rare and should be executed with excellent methodology (the exact opposite of SELECT).
So, when scientists study nutrients in isolation, e.g., dl-alpha-tocopherol (not the natural form with other important components), selenomethinine (without other key forms of selenium), beta-carotene (excluding other carotenoids) – then of course the outcome is rarely good. These are high doses of a single chemical that usually comes in a complex package.
In other words, super concentrated nutrients without the synergism of other key components are similar to pharmaceutical drugs and carry the same risk. But physicians who are nutritionally oriented know that – and have known that for a long time.
And, only integrative, functional, and naturopathic doctors are the experts in the responsible use of nutritional supplements.
So, no, don’t tell your doctor about the supplements you are taking (there is not one nutrition course in Harvard medical school) because she will not know what to do with that information unless she is a nutritionally oriented physician.
Nutrition science and botanical medicine is a discipline in its own right.
So, what should you do…
- Don’t just take supplements, but eat whole foods (organic as often as possible) from local sources when possible.
- Exercise for a minimum of 30 minutes a day and then still stay moving afterwards as much as possible.
- Most good research suggests you can benefit from taking Vitamin D3, so do so. Anything above 2000 units a day should be monitored by an integrative, functional or naturopathic doctor.
Other supplements may very well be helpful but it is always a good idea to seek the help of an expert. I have seen patients who often take way more than what they need.
Whew! This was a long one. 🙂
Leave comments below as I know this is a hot topic.
Helzlsouer KJ, Huang HY, Alberg AJ, et al. Association between alpha-tocopherol, gamma-tocopherol, selenium, and subsequent prostate cancer. J Natl Cancer Inst. 2000;92(24):2018-2023
Jiang Q, Wong J, Fyrst H, Saba JD, Ames BN. gamma-Tocopherol or combinations of vitamin E forms induce cell death in human prostate cancer cells by interrupting sphingolipid synthesis. Proc Natl Acad Sci U S A. 2004;101(51):17825–30.
Richie JP Jr, et al.Comparative effects of two different forms of selenium on oxidative stress biomarkers in healthy men: a randomized clinical trial. Cancer Prev Res (Phila). 2014 Aug;7(8):796-804.
Thomas R1, Williams M2, Sharma H2, Chaudry A3, Bellamy P4. A double-blind, placebo-controlled randomised trial evaluating the effect of a polyphenol-rich whole food supplement on PSA progression in men with prostate cancer-the UK NCRN Pomi-T study. Prostate Cancer Prostatic Dis. 2014 Jun;17(2):180-6