A big problem is that dietary supplements are not required by the United States to be standardized.
Americans spend billions of dollars a year on supplements in hopes of making up for the lack of nutrients in our diets, staying healthy, looking young and extending our lifespan. But do they actually work? The National Institutes of Health doesn't specifically recommend any daily supplements because there is no research or studies that show unequivocally that a specific supplement works. However, there have been studies that prove certain supplements do not work, such as ginko (to help memory) and echinacea (to ward off a cold). There are a few dietary supplements that show some benefits: calcium supplements and vitamin D (to reduce the risk of osteoporosis), omega 3 supplements (to reduce the risk of heart disease) and folic acid supplements (to prevent major birth defects).
Why is it so hard to test these supplements to find out whether they really are working?
Dr. Sanjay Gupta, CNN chief medical correspondent: A big problem is that dietary supplements are not required by the United States to be standardized. This means that the manufacturers are not making sure each batch has the same consistency or chemical makeup. And obviously different consistencies in the makeup of the pills are not going to provide consistent results in the studies, or in our bodies for that matter. The government actually warns consumers that if you see a supplement bottle that boasts the claim "standardized," it doesn't mean it actually is. In other words, just because they company puts it on the label doesn't mean it indicates product quality.
What about the super cheap supplements that are sold at closeout or discount stores? Are they safe?
Consumer Reports actually did a great investigation into this. They tested the supplements sold at closeout stores and compared them with name-brand supplements. Their testing found that nearly half of the brands failed to contain the labeled amount of the nutrient. They also didn't dissolve as well as the name-brand types. So if you are going to invest in a supplement, based on this study, a name-brand kind might be the way to go. One thing people don't really need to be concerned about is taking too much or too high of a dose. Our expert at Tufts University tells us that most supplements have a margin of about five to 10 times the dose before a person actually gets into toxic territory. He says Vitamin A is really the only supplement that, in high doses, could have a negative impact on your liver.
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