More than half of all U.S. adults are believed to use dietary supplements, but the government's chief drug regulator is fighting an uphill battle to ensure the supplements are safe.
The Food and Drug Administration (FDA) has not captured all reports on dangerous reactions to bad supplements, leaving consumers potentially vulnerable to health dangers.
"FDA may not have received information on all adverse events that are associated with dietary supplements because consumers and others may not be voluntarily reporting them," said a report by the Government Accountability Office, Congress' watchdog arm.
In fact, despite receiving 6,307 reports over four years on ba reactions to the supplements, GAO investigators noted that poision control centers received an additional 1,000 reports that did not make it to regulators.
The American Association of Poison Control Centers is a private organization that represents and assists the United State's 57 poison control centers.
FDA officials said they are working with the organization to try to get a complete picture of all bad reactions from dietary supplements. Currently, however, since the AAPCC is a private organization, the government would need to purchase the records of all reports, something GAO officials noted could be costly.
Even with the reports in hand, it is sometimes difficult to determine if the dietary supplement caused a bad reaction, FDA said.
"The core limitation of this system...is the challenge in determining whether reports in the system reflect cause-and-effect relationships between specific products and specific harms," said an FDA report. Due to this difficulty, the FDA does not rely solely on the reports to investigate unsafe products.
The term "dietary supplement" covers a wide range of substances from vitamins and minerals to animal by-products and botanical additives.
The reported number of adverse reactions has been steadily growing, a combination of more adults taking the supplements and the FDA strengthening regulations requiring companies to report problems surrounding their products.
But while companies are required to submit adverse reaction reports, the FDA has not created a system to allow filing the forms via the internet, instead relying on physical mail. GAO investigators said a digital submission process should be implemented - something FDA has planned since at least 2009 but has yet to implement.
Getting reports about the reactions is important in allowing FDA to act, because the agency cannot take action before the supplements are sold to consumers.
"FDA does not have the authority to require dietary supplements to be approved for safety and effectiveness before they enter the market, as it does for prescription drugs," investigators said.
The concern is not an abstract one. A supplement called botanical ephedrine alkaloids was linked to several deaths and banned in 2004. And last year the agency put out several safety alerts to warn consumers about Reumofan Plus that was being linked to fatalities and strokes.
Last year, the Washington Guardian reported that the federal investigators criticized the FDA for failing to properly regulate dietary supplement labels, allowing the products to make misleading and errant claims.
The use of the products has increased drastically in the past twenty years, GAO officials said, citing data from the Health and Human Services Department.
"The number of supplements on the market has grown exponentially, from an estimated 4,000 products in 1994 to an estimated 55,000 products in 2009," the GAO said.