Let's take a look with a spot light on the real story of multi-vitamins and should you continue to take yours.
Dan
http://easyhealthoptions.com/alternative-medicine/the-best-dietary-supplements/
EXCERPT:
The Best Dietary Supplements
Dr. Michael Cutler | Feb 10, 2014
It used to be that vitamins were scoffed at by regular mainstream physicians. But in 2002, a report inJAMA (the Journal of the American Medical Association) began to signal conventional support of their use.
Nevertheless, today, much confusion on the topic remains.
In my next few articles, I aim to uncover the controversy and facts about:
The value of nutrient supplementation.
The reasons why some vitamins have not been shown to reduce certain diseases.
The value of nutrient supplements from whole food sources.
Ways to decide which supplements are for you.
The supplements just about everyone should be taking.
The supplements good for specific illnesses.Why Controversy About Supplements Persists
It used to be that doctors mocked vitamin supplements and told patients they only led to expensive urine. Having been a mainstream medical doctor for many years, I understand where this thinking originated.
First, as students in medical school, we received only about one 60-minute lecture concerning nutrition in four years of medical education. In residency training we got even less. None of our physician-educators knew anything about the role of nutrition in health, and they had no grasp of the value of nutrient supplementation for the prevention or reversal of chronic illness. Furthermore, private-practice doctors receive expensive catered lunches from pharmaceutical salespeople to teach them about pharmaceutical drugs but are never wined and dined by people knowledgeable about nutrient supplements.
It wasn’t until July 2002 that the American Medical Association (AMA) finally endorsed the limited use of supplements (multivitamins with minerals) [1]. That report looked at vitamins A, B, C, D and E and concluded: “Inadequate intake of several vitamins has been linked to chronic diseases, including coronary heart disease, cancer, and osteoporosis.”
Important Topic
Yet the topic of vitamins and nutrient supplements is a really important one. It seems to be a dividing line between conventional medical thinking and natural or “alternative” health, but it shouldn’t be that way. The scientific literature helps us understand which type of nutrients work and which ones don’t.
We know there have been some large studies of supplements beginning in 1994. Some demonstrated benefits, while other found no benefits for taking certain single vitamins, such as vitamin A, beta-carotene and vitamin E.
At the same time, there have been an even larger number of studies showing overwhelming proven effectiveness for a whole lot of other nutrient supplements. Therefore, rather than attack all natural supplements, wouldn’t it be wiser and more valuable for us all to take an honest look at the nutrients and their studies so we know which ones work, which ones don’t and why?
Unfortunately, I often read one-sided opinion articles designed to sway readers away from nutrient supplements altogether (see below). There are even flawed studies that get published although they are seriously misleading. Because doctors are generally too busy to look at all the data researchers accumulate, they typically believe the study results that make headlines. Consequently, anyone who wants to know the truth about supplements can’t rely on a doctor but personally has to sift through the conflicting points of view.
It reminds me of how the tobacco industry fooled the public for many years even after it was reported in 1950 by the British Medical Journal [2] that smoking was strongly linked to lung cancer. Even after the 1964 U.S. Surgeon General’s “Report on Smoking and Health” proved the dangers of smoking, the tobacco companies wouldn’t admit the health risks.
It wasn’t until 1998 when the Tobacco Master Settlement Agreement [3] — a $207 billion cost to the tobacco industry — headlined the news that we all finally became clear that tobacco caused cancer. There have been an estimated 8 million Americans (157 million American life-years) saved from tobacco deaths over the past 50 years because of the tobacco laws that we implemented [4].
Flawed Studies
Through the years that I’ve searched the scientific literature on various topics, I have often found studies with results that support — and those that refute — the use of a certain natural interventions. Below are a few recent scientific reports that have fueled the confusion about the value of certain supplements. But by carefully looking at their study design and methodologies, we can learn more that is behind the headlines and authors’ conclusions.
The first article [5] was published in a 2013 Annals of Internal Medicine and concluded that “high-dose” multivitamins and minerals offer no benefit after heart attack. Subjects who had a previous heart attack were given either a multivitamin supplement or placebo and then followed for an average of 4.5 years for any heart event. Flaws of the study design include:
- An unacceptably high 46 percent of subjects in both groups discontinued the study after beginning it.
- The researchers concluded that that multivitamins don’t protect against cardiovascular risk at all even though the group taking multivitamins had an 11 percent reduction in time to death by any cause compared with the control group. Even before the study began, they had set their efficacy standard to be a 25 percent reduction in cardiovascular risk and anything less than this was to be considered “no benefit.”
- There were more subjects in the multivitamin group with diabetes (a well-known risk for heart disease) at baseline compared to the placebo group.
- The multivitamins used in this study contained a mere 100 IU of vitamin D (effective doses are 3,000 to 5,000 IU daily) and a mere 100 mcg of vitamin B12 (effective doses are 600 to 1,000 mcg in order to lowers levels of homocysteine, a known cardiovascular risk). For vitamin E, they used alpha tocopherol but did not use gamma tocopherol. (Clinical trials of alpha tocopherol alone have failed to show cardio-protective effects, whereas gamma tocopherol has consistently been associated with significantly lower cardiovascular disease [6].
Another recent study [7] also published in the Annals of Internal Medicine looked at the effects of low-potency multivitamin supplementation on cognition in aging males. The authors concluded that long-term multivitamin use had no value to improve cognition or memory in 5,947 male physicians with a mean age of 65 years who were followed for 13 years.
Consider that in 2007 the same journal published a study [8] of 4,052 male physician subjects followed for 18 years in which researchers found a significant cognition and verbal memory improvement in men taking beta carotene compared to placebo. Therefore, it’s interesting to consider design flaws that likely discredit their conclusion in this 2013 study:
- Adherence criteria were very low. If subjects took their multivitamin regimen just two-thirds of the time, it was considered adequate.
- The data relied on recollection by study participants as to how consistently they took their pills (inherently weak) in a questionnaire answered once a year. (another very inaccurate method), rather than counting returned unused pills (quality method).
- The daily vitamins used in this study were too low: only 60 mg of vitamin C (effective dose is 500 to 3,000 mg), 25 mcg of vitamin B12 (effective dose is 600 to 1,000 mcg), and 20 mcg of selenium (effective dose is 200 mcg). The authors even admitted: “[The] doses of vitamins may be too low…”
- Benefits were seen in the multivitamin group compared to placebo after 2.5 years, but this was not considered in their final conclusions.
Opinion Articles
Opinion articles about supplements are so often so one-sided that they are actually dishonest. An opinion article written by a rather well-known anti-supplement doctor, published in the June 8, 2013 issue of The New York Times Sunday Review [9] is entitled “Don’t Take Your Vitamins.”
This doctor points to what I call the “big five” published studies that failed to find benefits for supplements. One study demonstrated that when male smokers took supplements containing vitamins A, C, E, beta carotene and selenium, the nutrients didn’t improve their health, didn’t reduce the number of lung cancer deaths and might even have harmed their health [10] [11]. Another study found no benefits for those nutrients in improving gastrointestinal cancer rates [12]. An experiment with vitamin E and beta carotene did not find an improvement for overall mortality rates [13], and research on vitamin E did not show it to be worthwhile in postponing heart failure and prostate cancer deaths [14].
From these five studies, this doctor incorrectly concludes that all supplements are, therefore, a waste of time. In his summary statement he warns: “[C]onsumers don’t know that taking megavitamins could increase their risk of cancer and heart disease and shorten their lives…”
In a succeeding article [15] in the same newspaper, that doctor points to the nearly 50,000 annual adverse effects (and does not mention any deaths) reported by supplement users. At the same time, however, he neglects to mention the known 2.2 million annual adverse reactions reported in hospitalized patients [16] and the 106,000 deaths [17] directly attributed to prescription drugs each year in the U.S. He warns us all to “simply stay clear” of nutrient supplements.
In my next article I’ll provide an honest discussion of the nutrient supplements proven to be efficacious for disease prevention and treatment.
Keep feeling good,
Michael Cutler, M.D.
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