Multivitamins and Cancer Risk: Reading Between the Lines
October 21, 2012 by Robert Wascher
Filed under A Cancer Prevention Guide for the Human Race, Big Pharma, Cancer, Cancer Incidence, Cancer Prevention, Colorectal Cancer, Colorectal Cancer Risk, Drug Company Advertising, Minerals, Multivitamins, Nutrition, Prostate Cancer Risk, Risk of Death, Supplements, Vitamin D, Vitamins, Weekly Health Update, cancer risk, colon cancer, death, health, lifestyle, mortality, prostate cancer, rectal cancer, risk
A new study in the Journal of the American Medical Association claims that a daily multivitamin supplement reduces cancer risk….
MULTIVITAMINS AND CANCER RISK: READING BETWEEN THE LINES
As I discuss in my book, A Cancer Prevention Guide for the Human Race, recent high-level studies of common vitamins, including antioxidant vitamins, has dimmed the prior enthusiasm that these micronutrients can reduce the risk of cancer, or cardiovascular disease, in otherwise healthy individuals who eat a balanced diet. Moreover, recent prospective, randomized, placebo-controlled clinical studies have actually suggested that taking supplements of Vitamin E and Vitamin A (including beta-carotene) may actually be harmful to our health, while recent similar studies of Vitamin C supplements have shown neither apparent benefit nor harm.
Despite the almost uniformly discouraging recent research findings regarding most nutritional supplements and their alleged ability to decrease our risk of cancer and other serious illnesses, many people (as well as nutritional supplement manufacturers…) continue to hold out hope that popping a daily vitamin pill, or other nutritional supplement, will protect them from cancer and other dreaded diseases. (Meanwhile, most people still tend to ignore the evidence-based cancer prevention lifestyle and diet practices that I describe in A Cancer Prevention Guide for the Human Race, and which have been linked, by hundreds of reputable clinical research studies, with a 40 to 60 percent reduction in cancer risk.) So, it is not surprising to see the extensive and favorable media coverage that is being given to a newly published clinical study looking at the potential impact of daily multivitamin supplements and cancer risk, and which appears in the current issue of the Journal of the American Medical Association.
The Physicians’ Health Study II is a large, ongoing, prospective, randomized, placebo-controlled study of 14,641 male physicians in the United States. All of these men were at least 50 years of age when they entered into this public health study (the average age of all study participants when they entered into this study was 64 years of age). This study has observed health outcomes in this very large group of male physicians for an average of 11 years now, and the study’s authors have now reported on the impact of taking a daily commercial multivitamin supplement upon cancer risk and cancer-associated death rates.
To summarize the findings of this very large public health study, the male physicians in this study were secretly randomized to receive either Centrum Silver (a commercial multivitamin and mineral supplement) or a placebo (sugar) pill. At the time of their entry into this study, 1,312 of these male volunteers were noted to have a prior personal history of cancer. Following more than 11 years of observation, 2,669 of these physician volunteers were subsequently confirmed to have developed cancer, including 1,373 cases of prostate cancer and 210 cases of colorectal cancer. When compared with the men who were randomly (and secretly) assigned to the placebo group, the men who were assigned to the multivitamin supplement group experienced an observed, and modest (8 percent), but still significant, reduction in the risk of being diagnosed with cancer.
While this 8 percent reduction in overall cancer risk has been widely trumpeted by other media sites, it is important to note several significant caveats before you run out to the drugstore and buy a case of Centrum Silver. When one looks at the statistical analysis of the data that resulted in the claimed 8 percent reduction in cancer risk, one immediately notices that the so-called “confidence interval” for this claim extends to 0.998, which is right up against the limit of 1.0 that would render these findings statistically insignificant. Therefore, the single, sole positive finding in this study of a modest decrease in overall cancer incidence is, itself, at the very borderline of what most statisticians would consider to be a statistically significant finding.
In addition to the single modest (and only barely statistically significant) positive finding of this study, as I have noted above, there was no significant correlation between multivitamin use and the risk of developing prostate cancer, colorectal cancer, or, indeed, any other individual type of cancer. The absence of any identifiable decrease in the risk of any individual type of cancer in this study, likewise, further calls into question the validity of this study’s single, and statistically borderline, positive finding of an 8 percent reduction in overall cancer incidence among the group of men who were randomized to receive a daily multivitamin tablet. Moreover, this study also failed to reveal any detectable reduction in the cancer-associated death rate among the men who received a daily multivitamin tablet.
The rather breathlessly favorable media reaction to this study’s conclusions vividly illustrates how the superficial reporting of seemingly favorable clinical research findings can mislead the public into accepting overblown or invalid conclusions, such as those made by the authors of this particular research study. As I discuss in A Cancer Prevention Guide for the Human Race, most of the published research in the area of cancer prevention research is of relatively low quality in terms of the methods used to conduct such research. Moreover, as this particular prospective, randomized, placebo-controlled study shows, even clinical studies that actually utilize higher level methodologies still require both a careful and critical analysis of their findings and claims, and the conclusions of such studies should not be simply accepted at face value. While this multivitamin study makes the very simple and straightforward claim that taking a commercial multivitamin and mineral supplement “significantly” reduces the incidence of cancer (at least among middle-aged and elderly male physicians), even a cursory evaluation of this study’s data and conclusions confirms that there is likely to be little or no overall health benefit, in terms of cancer risk and cancer-related death reduction, associated with taking a daily multivitamin and mineral supplement in otherwise healthy and well-nourished adults. As the old saying goes, if something seems too good to true, it probably isn’t…..
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At this time, more than 8 percent of Americans are unemployed. According to the Bureau of Labor Statistics, however, the unemployment rate for veterans who served on active duty between September 2001 and December 2011 is now more than 12 percent. A new website, Veterans in Healthcare, seeks to connect veterans with potential employers. If you are a veteran who works in the healthcare field, or if you are an employer who is looking for physicians, advanced practice professionals, nurses, corpsmen/medics, or other healthcare professionals, then please take a look at Veterans in Healthcare. As a retired veteran of the U.S. Army, I would also like to personally urge you to hire a veteran whenever possible.
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New Government (USPSTF) Warning on Hormone Replacement Therapy Risks
June 3, 2012 by Robert Wascher
Filed under A Cancer Prevention Guide for the Human Race, Big Pharma, Blood Clots, Breast Cancer, Cancer, Cancer Prevention, HRT, Hormone Replacement Therapy, Hot Flashes, Incontinence, Menopausal Symptoms, Menopause, Progesterone, USPSTF, Weekly Health Update, breast cancer prevention, breast cancer risk, cancer risk, cancer screening, cardiovascular disease, coronary artery disease, dementia, estrogen, heart disease, memory, risk, stroke, women's health initiative study
A new report by a U.S. Government task force (USPSTF) recommends against the use of hormone replacement therapy due to serious health risks.
NEW GOVERNMENT (USPSTF) WARNING ON HORMONE REPLACEMENT THERAPY RISKS
As I discuss in my bestselling book, A Cancer Prevention Guide for the Human Race, there is now solid evidence that the most commonly used form of hormone replacement therapy (HRT) is associated with a significant increase in the risk of developing breast cancer, and that risk continues to rise with the duration of HRT use.
Like many cancer experts, I have taken issue with some of the U.S. Preventive Services Task Force’s (USPSTF) recent revisions of longstanding cancer screening recommendations, including, particularly, their 2009 recommendation that annual screening mammograms be started later in life than most experts have recommended (and continue to recommend), and performed less frequently among middle-aged women than most experts have also recommended. More recently, in 2011, the USPSTF’s blanket recommendation that routine PSA screening for prostate cancer be largely abandoned has not been warmly embraced by me, nor by many other cancer prevention experts, given that we still cannot determine, in advance, which men with prostate cancer will be helped by treatment for this disease and which men will not benefit (and, hence, may actually even be harmed) by being treated because they have an indolent form of prostate cancer that poses no threat to their lives (Does PSA Testing for Prostate Cancer Save Lives?).
Now, the USPSTF is weighing in on another controversial cancer-related issue: hormone replacement therapy. Prior to 2002, more than half of all American women took some form of HRT to treat the common symptoms of menopause, including hot flashes, night sweats, vaginal dryness, and irritability. As I discuss in my forthcoming book on the tragic history of HRT, The Manufactured Myths of Menopause and Hormone Replacement Therapy: A Legacy of Suffering and Death, the intentionally deceptive multi-decade marketing of HRT drugs as a panacea for the both the real and imagined consequences of menopause, and the skillful (if duplicitous) portrayal of menopause as a pathological disease that renders its “victims” something less than feminine, was only recently revealed to be a collection of gross distortions (to put it mildly) on the part of the dominant manufacturer of HRT medications. Thanks to the landmark findings of the enormous Women’s Health Initiative study, which was published in the Journal of the American Medical Association in 2002, we now know that long-term HRT use is clearly associated with an increased risk of multiple and serious health problems, including an increased risk of breast cancer.
The USPSTF is now about to weigh-in on the issue of HRT, in a paper that is to be released in the June 4th issue of the Annals of Internal Medicine. Unlike their other recent controversial pronouncements, however, I actually find the USPSTF’s new recommendations against the routine use of HRT to be very close to my own recommendations, and so I am including their review of the existing clinical research data on HRT in this column.
After comprehensively reviewing the data from 9 different prospective, randomized, placebo-controlled, blinded clinical studies (including the massive Women’s Health Initiative study), the USPSTF study group determined that both estrogen-progesterone (combination) HRT and estrogen-only HRT significantly increased the risk of stroke, potentially fatal blood clots (venous thromboembolic disease), gallstones, and urinary incontinence. Estrogen-progesterone (combination) HRT was also, once again, shown to be associated with a significantly increased risk of breast cancer, as well as a probable increase in the risk of dementia. (On the other hand, estrogen-only HRT, which can only be taken by women who have previously undergone hysterectomy, appears to actually decrease the risk of developing breast cancer, while both types of HRT also appear to reduce the risk of osteoporosis-associated bone fractures.)
Based upon the increasingly large amount of available clinical research data, HRT, of any type, cannot currently be recommended for routine long-term use, given the multiple and significant health risks associated with both estrogen-only and estrogen-progesterone forms of HRT. After decades of intentionally misleading advertising by the manufacturer of the two most frequently prescribed forms of HRT, and the manufacturer’s intentional co-opting of numerous women’s physicians over the years, the true risks associated with the long-term use of HRT have now become abundantly clear. I will have much more to say about this cautionary tale when The Manufactured Myths of Menopause and Hormone Replacement Therapy: A Legacy of Suffering and Death is published in early 2013….
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