When you buy a vitamin or some other type of nutritional supplement, you expect it to contain exactly what the label promises.

But about one out of every four supplements sold in the US does not meet this basic standard or has other quality problems, according to tests performed by ConsumerLab.com, an independent evaluator of supplements.

What’s Really In That Bottle?

The FDA requires supplement manufacturers to list exactly what's in their products on the labels, but there's little government oversight or enforcement to ensure that the products actually match the claims that are made on the labels.

As a result, supplements often contain less (or more) of the active ingredient that is listed on the label. In other cases, some supplements are contaminated with lead or other heavy metals...or they don't break down properly in the body, reducing a person's absorption of the supplement into the bloodstream.

Among the supplements that recently failed Consumerlab.com's independent testing…

Vitamin C

Vitamin C is one of the top-selling vitamins in the US.

Test results: Of 23 supplements tested this year, one-Dynamic Health Laboratories Liquid Vitamin C-contained only 43.5% of the amount of vitamin listed on the label. Liquid forms of vitamin C are more prone to chemical breakdown than nonliquid supplements.

Also, the label on one product had suggested a daily dose (up to 4,000 milligrams (mg] that exceeded vitamin C's tolerable upper intake level (UL) for adults age 19 and over.

*The products listed here have been evaluated by ConsumerLabs.com. Other evaluators of supplements include the US Pharmacopeia (USP) and NSF International. Talk to your doctor before taking any nutritional supplements

The UL, set by the National Academies of Science, is the maximum daily intake of a nutrient that is likely to pose no risk for adverse effects in healthy people. Excess vitamin C can cause stomach upset and/or diarrhea.

The Recommended Dietary Allowance (RDA) of vitamin C for adult men is 90 mg...and 75 mg for women. Some doctors recommend higher doses, but it's rare for anyone to need more than 500 mg to 1,000 mg daily.

Reliable products include..

  • Longs Wellness Vitamin C 500 mg.
  • Nature Made Timed Release Vitamin C 500 mg.
  • Schiff Immune Support Vitamin C 500 mg with Rose Hips a plant source of vitamin C).

Red Yeast Rice

Red yeast rice (made by fermenting rice with red yeast) contains cholesterol-lowering compounds, including lovastatin, which is similar to the active ingredient in some prescription statin drugs, and a related compound known as hydroxy acid. People who combine red yeast rice with lifestyle changes, such as exercise and weight loss, can experience drops in LDL "bad" cholesterol of 42%-an improvement comparable to that of a prescription statin drug.

Test results: Four of the 10 products tested had a total of only 0.1 mg to 1.3 mg of lovastatin and its hydroxy acid form per dose-levels that are far too low to have cholesterol-lowering effects. Four of the supplements were contaminated with citrinin, a potential toxin linked to kidney damage in animal studies.

Reliable products include…

  • Cholestene Red Yeast Rice (600 mg per capsule).
  • Chole-Sterin Red Yeast Rice (600 mg per capsule).
  • Healthy America Red Yeast Rice (600 mg per capsule).


Sales of turmeric supplements quadrupled from 2002 to 2006 following reports of significant health benefits, including relief from indigestion and ulcerative colitis (a potentially debilitating inflammatory bowel disorder that causes abdominal pain and diarrhea), rheumatoid arthritis and other inflammatory conditions. Some studies suggest that turmeric also may help prevent Alzheimer's disease.

Test results: Two of the 13 products tested -NSI Nutraceutical Sciences Institute Superior Turmeric Curcuma Longa and Solgar Standardized Full Potency Turmeric Root Extract showed high levels of lead.

In adults, excess lead can cause high blood pressure, decreased fertility and loss of sensation...in children and fetuses, it can severely affect mental and physical development.

Other results: Two turmeric products failed the tests because they provided only 11.5% and 49.5%, respectively, of the active ingredients (curcuminoids listed on each product's label.

Reliable products include…

  • Douglas Laboratories Ayur-Curcumin (300 mg per capsule).
  • Himalaya Pure Herbs Turmeric Antioxidant (400 mg per capsule).
  • New Chapter Turmeric Force (400 mg per softgel).


Beneficial probiotic bacteria in the intestine are essential for good health. They help balance the intestinal flora (hundreds of species of bacteria in the gastrointestinal tract) and also may stimulate the immune system.

Probiotic supplements are often used to replenish intestinal organisms that are killed by antibiotics-a common cause of diarrhea. Probiotics are also used to treat H. pylori infection (a common cause of ulcers).

Supplements should provide at least 1 billion viable (living organisms...daily doses of up to 10 billion are often recommended.

Test results: Four of the 13 products tested were found not to contain 1 billion organisms per daily serving. A fifth product (Flora Source) did contain 1 billion organisms daily, but not the 30 billion listed on the label.

Reliable products include…

  • Culturelle with Lactobacillus GG, All Natural (10 billion organisms).
  • Jarrow Formulas Enhanced Probiotic System, Jarro-Dophilus EPS (4.4 billion to 8.8 billion).
  • Nature's Way Primadophilus Optima, 14 Probiotic Strains Plus NutraFlora (35 billion).

Herbal Remedies Can Contain Toxic Metals

A study tested 193 Ayurvedic (traditional Indian) oral medicines made in the US or India -21% contained lead, mercury and/or arsenic in amounts exceeding regulatory standards. Most likely to contain toxic metals were products labeled rasa shastra a preparation combining herbs, metals, minerals and gems)...least likely were remedies from members of the American Herbal Products Association (www.abpa.org).

Do Expiration Dates on Nutritional Supplements Really Matter?

Expiration dates on nutritional supplements Cdo matter. However, the dates do not have to be treated as absolute deadlines, Supplements, just like medications and food, have a particular shelf life. Deteriorated products do not work as well—and could even be dangerous. Fish oil, for example, can become rancid and turn into a tissue-damaging pro-oxidant.

Most manufacturers label a product with a conservative expiration date that is well before the time the product is likely to deteriorate. I believe that nutritional supplements, if stored as recommended by manufacturers, generally can be used safely for up to three months beyond the stated expiration date.

Best: Buy supplements in quantities you expect to use before the expiration date.

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