Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passions, they cannot alter the state of the facts and evidence. – JOHN ADAMS
Directly from the CDC (Center for Disease Control) website are the following most common causes of death in America for 2007(1). This is the most current set of statistics available.
1. Heart disease: 616,067
2. Cancer: 562,875
3. Stroke (cerebrovascular diseases): 135,952
4. Chronic lower respiratory diseases: 127,924
5. Accidents (unintentional injuries): 123,701
6. Alzheimer’s disease: 74,632
7. Diabetes: 71,382
8. Influenza and Pneumonia: 52,717
9. Nephritis, nephrotic syndrome, and nephrosis: 46,448
10. Septicemia: 34,828
As you glance through this list, hopefully the most glaring absence is the category for multiple vitamins. Even though publications like Shape magazine used the headline, Your Multiple Vitamin May Be Killing You and the USA Today published the following story entitled, Study: Vitamins May Increase Death Risk in Older Women.
Let’s examine the Study
The multivitamin study was simply an observational study also called “prospective” or “cohort” studies and sometimes “epidemiological” studies. This means that it relied upon questionnaires from study participants and at its very best was going to be able to show correlation between action and event but not causation.
Researchers involved in this Iowa Women’s Health Study did adjust their results to take into account some of the more common variables. These included: BMI (body mass index), use of hormone replacement therapy, smoking status, alcohol intake, exercise and saturated fatty acid intake (2). Methods were vague as to how fatty acid intake was measured or recorded and remember that the study was conducted by questionnaire and not actual laboratory measurement.
One question, posed by many authors and researchers, is over compliance. In a follow-up of self-reported multivitamin use from 1986-2004, the respondents were to check mark a box saying that they indeed took multivitamins during this time period. However we don’t know which of them actually took them on a consistent basis and which dosages were used.
A deep examination of the statistics shows that researchers provided no information at all about actual nutrient levels garnered from these multivitamins. No blood tests were conducted and no customization was done for each individual. The two elements that were found to be most “dangerous” included copper and iron. Many patients will not need to raise their levels of copper and iron provided they have optimal levels at the onset. In clinical practice, the recommendations for multiple vitamins can be curtailed to match each person’s needs based on their own individual blood test results.
An important note in the study was that the mean age of participants was 61.6 years at baseline in 1986 (3). These people were followed with questionnaires from then to 2004. If you added 18 years to 61.6 that would make the average age of the person at the study’s conclusion 79.6. This exceeds the average life expectancy for a United States citizen by roughly 3-5 years depending on source used. How then are we sure that it was their multiple vitamin that shortened their lifespan? From 61-79 years of age, wouldn’t many of these people have succumbed to cancer, diabetes and heart disease?
What’s to say that the recent boom in elderly care vaccines (flu/swine flu, pneumonia, shingles, etc) didn’t play at least a role in these age related declines?
Observational studies are the kind most often reported in the media because there are so many of them. Shape magazine was irresponsible in running their headline Your Multi-Vitamin May Be Killing You. One would think their “health” columnists aren’t so naïve. More importantly, our media must act responsibly in explaining the whole story. Omitting the fact that this research was not based upon the gold standard of “double blind placebo controlled” criteria is in itself untruthful.
Even worse, one would expect articles published in the Archives of internal Medicine to be more critically reviewed and unbiased. However, this journal is notorious for only publishing negative studies about supplementation. Take a look at the American Journal of Clinical Nutrition and the Journal of Nutrition. You will see hundreds of well designed studies documenting the safety and effectiveness of supplementation. You can also refer back to our December 2010 Newsletter Understanding Supplement Labels and May 2008 Choosing a Multiple Vitamin.
As John Adams says, “Facts are stubborn little things.” Get the facts…the only way to know exactly what your diet should be like, areas you may need to supplement and what dosages should be attained is to seek out a trained health professional who can test you using objective testing methods.
References:
1. CDC.gov (http://www.cdc.gov/nchs/fastats/lcod.htm)
2. Daniells, Stephen. NutraIngredients October 2011. Multivitamins and mortality: “Seeing-what-you-want” Science.
3. Archives of Internal Medicine 2011; 171(18):1625-33
