Tuesday, August 28, 2012

Nine of the Most Popular Dietary Supplements: An Update

A pal who knows my interest in dietary supplements sent me a list he'd found of the top supplements recommended for men. I checked them out and will share the results below. (Most of them also would be on any list of the top supplements used by women.) But first....

Best Sources for Checking Out Dietary Supplements
Here are the first places I go when I have questions about dietary supplements. For an old guy, I'm pretty comfortable with online research, but I prefer reading from the page than from the computer screen. So I start with:
  • The Wellness Reports Dietary Supplements, 2012, published by the University of California, Berkeley, School of Public Health
  • The Mayo Clinic Book of Alternative Medicine
  • The Truth About Vitamins and Minerals, a Harvard Medical School Special Health Report
For online research, these are the sites I visit first:
If I want to dig deeper, I put the supplement name into Google's search box and add "-.com" (which usually excludes most of the commercial sites selling the supplement, which often dominate search results). Sometimes I hit "advanced search" and check results from the past year.

Whatever I type, I certainly find more than I really need to know... just one more example of my life-long practice of Mae West's advice -- "anything worth doing is worth overdoing."

Update on 9 Popular Supplements
So, here's what I found about that list of recommended supplements for men. Fish oil was also on the list, but we covered that in yesterday's posting. The print reports listed above provided much of what follows; I simply identify them as "Berkeley," "Mayo," or "Harvard."

Boron
I hadn't heard of this supplement before, and none of my usual sources covered it. So I did a Google search and found this summary from a 2009 study:

Boron is an element found in foods such as peanut butter, wine, grapes and other fruits, like peaches. While some reports have associated lower prostate cancer risk with higher boron intake, a large study involving over 35,000 men could not validate that finding. So, there is no official recommendation to take boron supplements to reduce prostate cancer risk.

Calcium
Some small studies over the years have suggested that calcium promotes weight control. But in a large, well-designed two-year clinical trial by NIH in 2009, findings showed that 1,500mg of calcium each day did not help control weight. In a German study of about 24,000 adults, researchers found that those who regularly took calcium supplements had an 86% higher risk of heart attack than those who didn't take the supplement.  Most authorities agree that it's better to get calcium from food than from pills. The recommendation is 1000mg of calcium a day, with an upper limit of 2000mg. Reminder: only 500mg can be absorbed at a time.

Chromium
Clinical trials in the U.S. involving diabetics have so far produced no clear evidence of benefit from chromium supplements. A Dutch study found no benefit from chromium in protecting against diabetes. (A Chinese study of chromium supplements did show results, but we downplay the finding here because the Chinese aren't fat like us (yet!), and chromium levels weren't evaluated at the start of the study.)

CoQ10
There are many conflicting studies. Some early small studies had lots of us with Parkinson's taking very high doses at very high  prices, but a later large study found no benefit. While Mayo, Berkeley and others suggest "don't bother," I still take 200mg a day, since some studies report heart health and blood pressure benefits, and no dangerous side effects have been reported.

Creatine
Berkeley: "There's no reason for most people to  take creatine. It may give some competitive athletes a small edge, but this is meaningless for recreational athletes and exercisers." Those with kidney problems should avoid it.

Folic acid
A British study showed a possible reduced dementia risk from taking large doses of B-12, B-6 and folic acid.  But another study found that the risk of prostate cancer doubled for men taking folic acid supplements of  1000mg a day.

Glucosamine
Mayo: Many older studies showed promising results in relieving arthritis pain. But the results of a large NIH-sponsored trial were mostly negative. Only those with very severe arthritis appeared to benefit. But it has few side effects, and it might help. Berkeley: Forget about it "unless you are willing to pay $20 or more a month for what is probably a placebo."

Selenium                      
Berkeley: "Eat foods rich in selenium, such as whole grains and nuts, but skip the supplements because of the inconsistent research results." If your diet provides the recommended daily allowance (RDA), additional selenium could be risky. If you do take a selenium supplement, take no more than 200mg a day. Mayo: Same. Selenium deficiency is rare, and mostly occurs with severe gastrointestinal problems. "Despite some earlier studies, recent research indicates that selenium does not significantly lower cancer or heart disease risk."

Vitamin E
Berkeley:  "There is little or no clinical research showing that vitamin E supplements are beneficial.... In fact, the evidence is growing stronger that vitamin E supplements might actually be harmful." Mayo and Harvard agree.

Bottom Line: Get Nutrition from Diet, Not Supplements
Most sources agree: we should obtain our vitamins and minerals from food, not supplements. But NIH cautions that we might need supplements in these situations:

·        Over age 50: Tougher as we age to get enough B-12, calcium and vitamin D
·        Post-menopausal women: May need calcium and vitamin D supplements
·        Dark-skinned, or getting less than 15 minutes of sun exposure daily: May need extra vitamin D
·        So frail and elderly that they can't eat sufficient amounts of food
·        Those with nutritional deficiencies from restricted diets: Vegans, people undergoing weight-loss surgery
·        Suffering from a medical condition: Some illnesses like cancer, anemia, and celiac disease cause nutritional deficiencies that may require supplements
·        Undergoing medical treatment:  Some medicines, such as cancer drugs and proton pump inhibitors, can interfere with nutrient absorption

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