Wednesday, August 8, 2012

Surprising Dangers of Vitamins and Supplements

That's the banner headline across the cover of the September, 2012 issue of Consumer Reports. The subtitle is "How To Protect Your Family."

Here's the link if you want to see the full report. The parts that resonated with me are summarized below.

Supplements are not risk-free
More than 6,300 reports of serious adverse events associated with dietary supplements were reported to the FDA between 2007 and mid-April 2012. The reports described more than 10,300 serious outcomes, including 115 deaths and 2,100 hospitalizations.

The FDA receives many more reports of adverse effects from prescribed medications. But there's one big difference, notes Peter Cohen, M.D., internist at Cambridge Health Alliance in Massachusetts. When it comes to prescribed meds, "these powerful medications with powerful side effects are actually saving lives when used appropriately." But with supplements, "there's rarely a powerful lifesaving effect."

Current laws make it difficult for FDA to act against problem supplements. The FDA has banned only one ingredient, ephedrine alkaloids, used in weight-loss products, and that effort dragged on for a decade during which ephedra products were implicated in thousands of adverse events, including deaths.

How to protect yourself:  CR recommends you type the name of any supplement you're thinking about using into the search box at www.fda.gov to see if it has been subject to warnings, alerts or voluntary recalls. Tell your doctor if you think you're having a bad reaction to a supplement. You can report any problem with a supplement to the FDA at 800-332-1088 or www.fda.gov/medwatch.

Some supplements are really prescription drugs
Dietary supplements spiked with prescription drugs are "the largest single threat" to consumer safety, according to Daniel Fabricant, director of FDA's Division of Dietary Supplement Programs. Most of these  threats come from products marketed for bodybuilding, weight loss, and sexual enhancement.

The FDA has received reports of strokes, acute liver injury, kidney failure, pulmonary embolism (blood clots in the lungs) and death associated with drug-tainted supplements.

How to protect yourself.   Avoid using supplements for body building, weight loss, or sexual help. If you suspect you've purchased a product tainted with undeclared prescription drugs or steroids, send an email to the FDA at taintedproducts@fda.hhs, gov.

You can overdose on vitamins and minerals
Unless your health care provider tells you that you need more than 100 percent of the recommended daily intake of a particular nutrient, you probably don't, CR indicates. It quotes Marion Nestle, professor of nutrition and public health at New York University, who says:
It doesn't make sense to me to take huge doses of vitamins and minerals unless there's a diagnosed problem, because there is so little evidence they do good and sometimes a problem they may do harm.
It's surprisingly easy to overdo it. Most of us don't pay attention to the amounts of extra vitamins and minerals we get from fortified cereals, and we're unaware of what we get from the food in our regular diets.

How to protect yourself.  The Consumer Reports article includes a table showing the recommended daily intake and safe upper limits for the most common vitamins and minerals. It recommends that we take the information from the labels of the supplements we use, add in our intake from other sources, and then check it against the table. I suspect very few of us will take the trouble to do this.

It also says that if your doctor says you need more of a specific nutrient than you can get from food (or from sun exposure in the case of Vitamin D), a single pill may be sufficient.

A personal note:  As a result of the blood tests taken at my annual physical in April, my internist recommended that I take a daily supplement of 1000mg of vitamin D (a common recommendation for the elderly). I'm doing that. But I'm also, without his advice, taking daily supplements of 5-HTP, curcumin, and CoQ-10. I'm doing this because my extensive  internet research on health issues shows that very promising studies have been done on curcumin and CoQ-10 in areas of particular concern to me. While the standard advice is to wait for results from larger trials, I'm running out of time to wait for those results. I'm taking a gamble, but I monitor my health pretty carefully and it seems to be worth the risk for me. In the case of 5-HTP, I've had years of mostly favorable experience with this supplement in aiding my sleep and mood. I did have a problem with spikes in my blood pressure seemingly caused by upping my dose of 5-HTP, so I closely monitor my blood pressure and my daily use of 5-HTP. (If you want more information on my experience with any of these supplements, just enter the name in the search box in the right-hand column of the blog.)

You can't rely on warning labels for supplements
The FDA doesn't require warnings on supplements. Supplement makers can provide warning labels if they want to. CR looked at 233 popular supplement products, all purchased online or in stores in the NYC metropolitan area this spring. It reports that "the only thing consistent about the labels is their lack of consistency."

For example, it's known that St. John's vort can reduce the effectiveness of certain prescribed meds, such as birth control pills and blood thinner. Yet only two of the 17 samples it purchased contained that warning.

How to protect yourself:  CR says you should make sure your doctor or pharmacist knows what supplements and prescription drugs you are taking. It also suggests you learn about interactions in its free "Guide: 100+ Commonly Used Supplements" in the Natural Health section at ConsumerReports.org.

Personal note:  I find  it easy and useful to check out supplements at Mayo Clinic's online site for "Drugs and Supplements: -- http://www.mayoclinic.com/health/drug-information/DrugHerbIndex.

Ignore claims that a supplement can cure a major disease
If you're surfing the internet and come across such a claim, "surf right off to another site," CR says. Such claims "are a direct threat to public health," an FDA spokesman says. The FDA has sent dozens of letters to companies warning them to stop making such claims. And the Federal Trade Commission has brought more than 100 legal challenges to claims about the effectiveness of supplements.

How to protect yourself:  CR recommends researching any supplement on the FDA's website (www.fda.gov), the National Institutes of Health's Office of Dietary Supplements site (ods.od.nih.gov), or via the National Center for Complementary and Alternative Medicine (nccam.nih.gov).

Personal note:  Again, I find the Mayo Clinic site easy and useful.  For those interested in more in-depth research, the best starting place is the National Institutes of Health's PubMed site: http://www.ncbi.nlm.nih.gov/pubmed/

Questionable claims for fish oil, antioxidants, and calcium supplements
Here's what CR says about the claims for these popular supplements :
  • German and Swiss researchers who followed 24,000 adults for an average of 11 years found that regular users of calcium supplements had an 86 percent greater risk of heart attacks than those who didn't use the supplements AND that there was a 30 percent reduction of heart attack risk among adults with a moderately high intake of calcium from food itself. The reason for the disparity, researchers reasoned, is that the supplements may cause risky quick spikes in calcium levels, while the calcium in foods is absorbed more slowly.
  • A study of 12,500 people with diabetes or prediabetes and a high risk of heart attack or stroke found no difference in the stroke/heart-attack death rate or other outcomes between those give a fish oil pill every day and those given a placebo. The results may be clouded, CR acknowledges, by the fact that the participants were taking other heart medications. Most of us can get enough omega 3s by eating fatty fish twice a week. (I have a tin of sardines or a helping of pickled herring for lunch at least twice a week.) Those with coronary artery disease, nevertheless, might want to talk with their doctors about taking a fish oil pill, CR advises.
  • Recent studies have shown no evidence to support the health claims made for the anti-oxidant vitamins A, C or E, or for beta carotene or selenium. Instead, researchers noted, "Some clinical trials show that some of these antioxidant nutrients may increase cancer risk."
You may not need supplements at all
Most of us get all the nutrients we need by eating a variety of fruits, vegetables, cereals, dairy and proteins. There's little nutritional benefit to be gained from taking nutritional supplements and some could be harmful. Here's CR's take on the top selling vitamins and on mutii-vitamins:
Vitamin A:  Few people in the U.S. are deficient in Vitamin A. Too much retinol, the form of Vitamin A that comes from animal sources such as eggs. liver, and whole milk, can cause birth defects and liver abnormalities and might also harm the bones.
B vitamins:  Most of us get plenty through our diet. Vegetarians, however, might need extra B12, which might also be true for the 10-30 percent of people over 50 who don't have enough stomach acid to extract B12 from food. Also women who are pregnant or trying to get pregnant should take 400mg a day of extra folic acid to prevent birth defects.
Vitamin C:  There's some evidence that 200mg of vitamin C a day might improve cold symptoms in smokers and seniors, though it won't prevent colds.
Vitamin D:  You probably don't need a supplement if you get some midday sun exposure during the warmer months and regularly consume vitamin D-rich foods like fatty fish, eggs, and fortified dairy products. (But you'd be crazy to expose yourself to midday sun during the summer we're having in D.C.) But people who are middle-aged or older -- or overweight or dark-skinned -- might need supplements. If you're unsure, ask your doctor for a blood test.
Vitamin E:  Two studies have linked as little as 400 IU a day of vitamin E to a small but statistically significant increase in mortality. Moreover, vitamin E may inhibit blood clotting, so it shouldn't be taken with blood thinners.
Multivitamins:  Large clinical trials have repeatedly found that multivitamins don't improve the health of the average person. Groups that might need a multivitamin include women who are pregnant, breast feeding, or trying to conceive; dieters consuming fewer that 1200 calories a day or avoiding a whole food group such as carbohydrates; and people with medical conditions that affect digestion or food absorption..                                                                                                                                                                                    

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