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Newsletter - New Secrets About Health and Wellness - Heart Attack, Stroke and Cholesterol December 17, 2013 |
Yours in Health and WellnessDon’t Believe the NewsIt is a sad reality that there is very little in-depth news reporting of news, especially of health news. So we get a one or two day headline like “Experts Say Don't Waste Your Money on Multivitamins”. Before you believe any of that you have to ask yourself three key questions: • What experts? • What studies? • What multivitamins? .
I am not going to review all the studies that show the efficacy of vitamin and mineral supplements. I have a whole book about them. You can find a very brief summary
here (in a new window).
WebMD summarized one study in the news as follows: “For the first study (Guall and O’Brien Annals of Internal Medicine), researchers randomly assigned almost 6,000 male doctors over the age of 65 to take either a daily Centrum Silver multivitamin or a look-alike placebo pill. Every few years, the researchers gave the men a battery of tests over the telephone to check their memories.” A placebo is a pill or tablet that looks the same as the one being tested, but it has no active ingredients. The study can be found at Ann Intern Med. 2013;159(12):806-814. Unfortunately Centrum Silver is a mediocre product. An independent third party rated over 1600 multi-vitamin products on a scale of 1 to 5 stars. (MacWilliam, Comparative Guide to Nutritional Supplements 2007: Fourth Edition) The Centrum Silver used in this study rated 0.5 star. That’s right ½ star. So that is really like testing a placebo against a placebo. There are products that have been shown in double-blind placebo-controlled studies to protect the brain against cognitive decline. Multi-vitamins sometimes contain some ingredients, especially certain antioxidants that help protect against endothelial (arterial wall lining) dysfunction, one of the first serious signs of cardio-vascular disease. That helps somewhat by maintaining more efficient flow of blood providing nutrients to and exiting wastes from the brain. The other way multi-vitamins can help is if they have enough folic acid, B6 and B12 to keep homocysteine at a safe level as covered in detail in
the previous Newsletter on homocysteine (new window)
The second study by Lamas, Boineau et al found at Ann Intern Med. 2013;159(12):797-805 set out to assess whether oral multivitamins reduce cardiovascular events after a preceding heart attack. The results are at best inconclusive and seriously limited by “considerable nonadherence and withdrawal, limiting the ability to draw firm conclusions”. The third study, a literature review, by Fortmann, Burda et al sought to “to systematically review evidence for the benefit and harms of vitamin and mineral supplements in community-dwelling, nutrient-sufficient adults for the primary prevention of cardiovascular disease (CVD) and cancer”. A major limiting factor in this study is that the researchers only included studies in which “supplement doses [were] lower than the upper tolerable limit set by the U.S. Food and Nutrition Board”. That is the dose level had to be lower than the Dietary Reference Intake, which is way below the level for optimal health. The studies were also limited to “adults without known nutritional deficiencies… and studies were conducted in older individuals and included various supplements and doses.” Thus there is no recognition that the number of ingredients, the necessity for certain ingredients, their ratios, quality, purity, and bioavailability are all factors determining the efficacy of supplements. So we already have a number of confounding variables. To their credit the authors did note there were limitations to their report. Given all these considerable limitations how could this issue of the Annals of Internal Medicine preface these studies with an editorial irresponsibly titled “Enough is Enough: Stop Wasting Money on Vitamin and Mineral Supplements” and to go on to say “The message is simple: most supplements do not prevent chronic disease or death, their use is not justified, and they should be avoided.” The conclusion is not supported by the evidence. I am saddened to see that this journal has allowed its standards to lapse to this extent. What do you think? Would you like to see a more detailed analysis of these three studies?
The Take-AwayAlways treat glaring (or blaring) headlines with a grain of salt.Yours in health and wellness, Roger
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