I’ve never been a fan of herbal supplements (or any supplements for that matter). There are cases where there is a specific medical condition that needs to be treated by a specific compound. For example, my wife has a mild anemia and her doctor prescribed an iron supplement during her pregnancy.
But in general, supplements are not useful. The vast majority of them, especially the herbal supplements are not regulated by the FDA.
Although dietary supplement manufacturers must register their facilities with FDA,* they are not required to get FDA approval before producing or selling dietary supplements. http://www.fda.gov/Food/DietarySupplements/
There is little or no evidence that they do anything at all. Even when they contain what they say they contain… which, apparently, they don’t.
Let’s look at the second part of that paragraph from the FDA site.
Manufacturers and distributors must make sure that all claims and information on the product label and in other labeling are truthful and not misleading.
Personally, I think that it is highly misleading to claim that a supplement does things like “help sleep” or “manage weight” when there is no scientific evidence to support such a claim.
But the supplement manufacturers and retailers apparently can’t even meet that level of scrutiny. The New York State Attorney General found that the majority of herbal supplements in four major stores (Walgreens, Walmart, Target, and GNC!) don’t even contain the herbs that they claim to contain.
…overall, just 21% of the test results from store brand herbal supplements verified DNA from the plants listed on the products’ labels — with 79% coming up empty for DNA related to the labeled content or verifying contamination with other plant material. The retailer with the poorest showing for DNA matching products listed on the label was Walmart. Only 4% of the Walmart products tested showed DNA from the plants listed on the products’ labels.
The AG’s office conducted DNA screenings, looking for specific pieces of DNA that would identify the herbal supplement in question. They didn’t find it very often.
Now, some people suggest that the herbal processing damages and/or removes the DNA and makes it unlikely to be seen in the supplements. There’s two problems with this ad hoc explanation (three if you count the evidence that is contrary to the claim). The first is that if the manufacturing process is so intense as to destroy DNA (which is a fairly robust molecule), then it is likely that proteins and other components of the herbs are destroyed as well. Meaning that there’s no point in taking the supplement.
The second issue is that, there was DNA discovered in the supplements. This DNA belongs to plants that were not on the label, which is a big problem.
While overall 21% of the product tests confirmed DNA barcodes from the plant species listed on the labels, 35% of the product tests identified DNA barcodes from plant species not listed on the labels, representing contaminants and fillers. A large number of the tests did not reveal any DNA from a botanical substance of any kind. Some of the contaminants identified include rice, beans, pine, citrus, asparagus, primrose, wheat, houseplant, wild carrot, and others. In many cases, unlisted contaminants were the only plant material found in the product samples.
The study seems to be a well conducted study (based on what the AG office published).
“The investigation looked at six different herbal supplements sold at the four major retail companies in thirteen regions across the state,”
The DNA tests were performed on three to four samples of each of the six herbal supplements purchased from the New York stores. Each sample was tested with five distinct sequence runs, meaning each sample was tested five times. Three hundred and ninety tests involving 78 samples were performed overall.
So, even if the supplements do what they claim, it doesn’t matter because it’s much more likely that the supplement doesn’t actually have that herb in it.
“The evidence for these herbs’ effectiveness is sketchy to begin with,” said David Schardt, Senior Nutritionist of the Center for Science in the Public Interest. “But when the advertised herbs aren’t even in many of the products, it’s a sign that this loosely regulated industry is urgently in need of reform.
Or we need to teach people about some real science and to quit spending $61 billion a year on ground up houseplants and grass.