There is More Regulation of Your Dog's Medicine than Your Dietary Supplements

Did you know that in the U.S. drugs for animals are regulated by the Food and Drug Administration (FDA), which means that they must be shown to be safe and effective, and are manufactured under tightly controlled conditions?

Did you know that dietary supplements for people generally receive little-to-no scrutiny by FDA?

Last week's Science had a nice story of one physician's David-and-Goliath fight against tainted supplements. It all began when Dr. Pieter Cohen noticed that patients taking the same weight loss supplement started getting sick. This started him on a quest of testing various supplements for extra substances (chemicals, hormones, etc) and his work is getting the FDA's attention.

To understand the regulatory issue, you need some background. The dietary supplement industry is practically a libertarian's dream:

THE MODERN SUPPLEMENT ERA began in 1994, when Congress passed the Dietary Supplement and Health Education Act, or DSHEA (pronounced duh-shay-uh). In the decades before, the supplements industry was overwhelmingly focused on vitamins and minerals. Much of the regulation centered on recommended daily allowances of products like vitamin C, iron, or calcium.

DSHEA established the first broad framework for regulating supplements. It also gave supplements a legal definition: as substances intended to “supplement the diet,” containing “dietary ingredients” such as herbs, botanicals, or vitamins.

At the same time, the law sharply curtailed FDA's power. Companies were not required to notify FDA provided the dietary ingredient had a history of use before the law was passed. For the first time, DSHEA allowed them to make claims on the label suggesting supplements affected the structure or function of the body—for example, by boosting the immune system or protecting prostate health. And DSHEA codified a loose arrangement: Under the law, as FDA notes on its website, “unlike drug products that must be proven safe and effective for their intended use before marketing, there are no provisions in the law for FDA to ‘approve’ dietary supplements … before they reach the consumer.” The agency can act only after a supplement is on the market and evidence shows it's unsafe.

The article is accompanied by a graphic that says that "prescription and illegal drugs are routinely found in supplements." It has two examples of supplements that are supposed to help with sexual enhancement. Any guesses what was found in them? Answer: Viagra. The article gave me a little more sympathy for athletes who claim that they didn't know their supplements contained a banned substance. They really may not have known!

FDA has a Q&A page about supplements. It's worth reading through the whole thing, but check out this gem:

Do manufacturers or distributors of dietary supplements have to tell FDA or consumers what evidence they have about their product's safety or what evidence they have to back up the claims they are making for them?

No, except for rules described above that govern "new dietary ingredients," there is no provision under any law or regulation that FDA enforces that requires a firm to disclose to FDA or consumers the information they have about the safety or purported benefits of their dietary supplement products. Likewise, there is no prohibition against them making this information available either to FDA or to their customers. It is up to each firm to set its own policy on disclosure of such information.

The next time you are in the pharmacy, have a look at all of the products with the disclaimer that their claims have not been evaluated by the FDA.

I'm going out on a limb here, but my sense is that straight-up vitamins and similar products are not the main problem (though they may indeed be a waste of money [1]). Rather, in my opinion products that are claimed to actually help some kind of performance (strength, sexual, weight loss, etc) are more likely to have some kind of drug or hormone to help produce the desired effect, or the illusion thereof. Most people who take a multivitamin or similar product are not going to notice any substantial difference in their health, nor will they care. But when it comes to, say, weight loss supplements, consumers will expect to see some progress. The balance of incentives and disincentives to play fast and loose with the truth and your safety are quite tilted toward the manufacturer.

The irony of course is that many consumers of dietary supplements are operating under the illusion that they are avoiding 'unnatural' substances, or that the law wouldn't let manufacturers put claims on the bottle that are not true. In reality, most consumers don't really know what they are consuming, and don't realize how little evidence manufacturers need behind their products.

You have been warned.


Notes:
1. Most people get all the nutrients they need from their diet. However, I fully accept that some dietary supplements may be helpful for some people.

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Book of Mormon DNA Apologetic Arguments Have a Shelf-life

There have been a couple of scientific advances on Native American origins this summer. First, DNA was finally isolated from the 9,000 year-old Kennewick man (KM) and it is clear that he is closely related to several current Native American tribes. Some had argued based on skull morphology that KM was more closely related to Australians and that his ancestry was outside of the East Asian/Siberian mainstream. However, the genetic evidence now puts him firmly within the Native American mainstream.

The second finding, reported by two separate groups a couple of weeks ago, is that some Amazonian tribes have a small DNA contribution from a common ancestor of indigenous Australians and Melanesians. This Boston Globe article is one of the better ones I have seen (and it has a nice accompanying graphic). It is very easy to get confused by the differing interpretations of the data. From what I have read, it boils down to this: Does the Australian DNA come from migrants who came into the New World around the same time as the East Asians/Siberians (>15,000 years ago), or later through the Aleutian Islands around 9,000 years ago? Some news articles use the terms ancient and recent without being clear about the associated dates, which can lead people to imagine evidence of trans-Pacific voyages. That is NOT what is proposed here.

At first glance this has nothing to do with the Book of Mormon. The Asian ancestry of Native Americans is nothing new, and the timing of the migrations inferred from the above studies occurred long before the Book of Mormon chronology. Defenders might even point out that the added complexity that has been discovered shows that we must remain open-minded about Native American genetics because surprises do happen. However, there may be subtle implications for the future of Book of Mormon apologetics, which rely heavily on the population genetics principles of founder effect, genetic bottlenecks, and genetic drift.

To make things easy, I'll break my point up into several bite-sized propositions:

1. Although the exact genetic signatures that the Jaredites/Lehites would have carried are unknown, each advance in characterizing the ancient origins of Native American genetics helps to establish the background from which Jaredite/Lehite markers would stand out. We may not know exactly what we are looking for, but we have an increasing ability to recognize markers that are unusual.

2. Mitochondrial DNA and Y chromosome types are particularly sensitive to genetic drift, etc.--a point made in the two papers describing the Australian connection. Originally most ancient genetic research focused on mtDNA and Y chromosomes because they were easier to deal with. However, the technological advances in recovering and sequencing autosomes (i.e. most of the genome) have greatly improved in the last decade.

3. Autosomal markers are more resistant to disappearing from populations. It's one thing for mtDNA or Y chromosomes (which are inherited by daughters and sons, respectively, as a block) to go missing; it's another for all traces of autosomes (which mix by recombination each generation) to disappear. As an example, scientists initially ruled out interbreeding between modern humans and Neanderthals based on mtDNA differences. However, once the Neanderthal genome was sequenced, it became clear that modern humans of ancient European decent got about 4% of their DNA from Neanderthals (which went extinct ~30-40,000 years ago).

4. The increased ability to recover and sequence DNA from ancient remains means it is probably only a matter of time before a variety of genomes dating from Book of Mormon times--and in the favored locations--are recovered. It is one thing to explain why modern Native Americans do not show any genetic relationship to the Middle East; it is another to explain why two thousand year-old Mesoamerican remains do not show any genetic relationship.

I am not suggesting that genetic studies are going to definitively disprove the Book of Mormon as an ancient American record. What I am suggesting is that, as the science around Native American origins progresses and the realm of plausibility contracts, the current arguments that Book of Mormon defenders advance with respect to Native American DNA will begin to wear thin. That is, unless a pre-Columbian Middle-Eastern genetic signal is discovered. But if that happens, we won't need the current arguments any more. So either way, we are marching toward their expiration date.

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