How Shoddy Science Is Driving A Supplement Boom

FLORA LICHTMAN: This is Science Friday. I’m Flora Lichtman. Dietary supplements are big business. One recent estimate shows the industry is worth almost $64 billion just in the United States. And, in fact, chances are you take a dietary supplement. Most Americans do. It’s hard to escape the claims about some new vitamin or mineral that will give you more energy, or make you stronger, or make your brain work better.

SPEAKER 1: If you need caffeine to function, take vitamin B12. If you carry too much in your midsection, take ashwagandha.

SPEAKER 2: Here are some of my favorite weight loss supplements. Number 1 is black seed oil.

SPEAKER 3: So I recently started taking the supplement that has been a game changer for my PCOS. I’m talking about CoQ10, which is–

FLORA LICHTMAN: But how effective are supplements? How safe are they? How are they regulated? And why are these remedies so appealing to us? Here to help us size up of science and culture of supplements are Dr. Pieter Cohen, head of the supplement research program, an associate professor of medicine at Harvard Medical School, and an internist at the Cambridge Health Alliance based in Somerville, Massachusetts. And Dr. Colleen Derkatch, author of Why Wellness Sells: Natural Health in a Pharmaceutical Culture. She’s also a professor of rhetoric at Toronto Metropolitan University, based in Ontario, Canada. OK, welcome to you both to Science Friday.

PIETER COHEN: Thanks for having us.

COLLEEN DERKATCH: Yes, hi. Thanks.

FLORA LICHTMAN: Let’s start with some definitions. Pieter, what makes something a dietary supplement versus a medication?

PIETER COHEN: That’s a great question. A dietary supplement doesn’t really mean anything. It’s just a legal term that was invented over 25 years ago by Congress. And it’s part of the law to combine many different types of ingredients together into this category of dietary supplements. So they can include vitamins, minerals, amino acids, protein powders, botanical, porcine, thyroid extracts, live microorganisms like bacteria and fungus, so it’s a real mixed bag.

FLORA LICHTMAN: This is a big bucket, I’m hearing.

PIETER COHEN: Very big. Yeah.

FLORA LICHTMAN: Colleen, what about our perception. I mean, how does our perception of what a supplement is match with this bucket.

COLLEEN DERKATCH: It’s about as varied as the bucket itself, I would say. Yeah, people think of supplements as all kinds of things. They think of them as fundamentally distinct from pharmaceuticals. And that’s one of the reasons why they’re so powerful. People really believe that they are basically farm to capsule, that these are plants that are grown in very kind of bucolic fields with little down home families farming and somehow they magic their way into capsule form.

And the similarities to pharmaceuticals become a lot murkier. They are pills in bottles, they are synthesized in labs, there’s a lot of correspondence between the two things. They are products that people take to effect a change in the body. And for a lot of people, that’s really appealing because they may be concerned about what’s going into pharmaceuticals, they may be concerned about the pharmaceutical industry, they may be feeling like doctors don’t really care about their health or don’t get to root causes. And so supplements are able to behave like both things at the same time. And I think that that’s really powerful. People do find that quite appealing.

FLORA LICHTMAN: How does supplement culture intertwine with MAHA culture and this move towards you being in charge of your own health?

COLLEEN DERKATCH: I mean, from where I sit, it’s not surprising to me. So if you look at the history of wellness culture, it has always had a really strong libertarian streak to it. And I think we’re seeing some of that come to fruition right now. When people use supplements, they frequently serve primarily as symbols of other things. And I think that that’s what’s really important is that the actual intervention that people buy and swallow with water represents so much more than just what’s in the capsule or the pill.

And people are seeking to return to a state of purity. And whether that’s purity from chemicals that they think are in their body, or chemicals from pharmaceuticals, or even if they just want to do something for themselves to make them feel better, to make them feel like they’re taking care of themselves, to make them feel like they’re good people, and a lot of that connects back to decades now of public health messaging in both the US and in Canada, where I live, that we are, each of us, responsible for our own health. We each need to take steps to support and enhance our health and supplements really tap into that.

FLORA LICHTMAN: Pieter, how are dietary supplements regulated?

PIETER COHEN: So here in the United States, the concept is that all those ingredients we were talking about are presumed to be safe to consume and can be sold directly to consumers. The FDA is just in the position, who technically oversees supplements– the FDA is in the position of just keeping an eye out and in case there is something that they detect, that there’s danger coming from the supplements, they can take steps– small, baby steps, actually– to try to remove those products from the marketplace. So it’s very much reliant on the industry to self-police and ensure that their own products are safe.

FLORA LICHTMAN: I mean, “presumed safe” sounds unnerving to me, personally.

PIETER COHEN: Well, the concept came around because of the FDA’s efforts, back in the 1970s and to 1980s, to try to more tightly regulate vitamins and minerals. And the FDA made some moves to try to make it such that certain high doses of vitamins like, let’s say, a dose of 10 or 20 times what was necessary in a day– if that was going to be marketed, that should go through a more stringent regulatory review by the FDA. And it was in a backlash against that move by the FDA that led to the current laws that really tell the FDA hands-off here. We can sell what we want to and consumers can purchase what they want to.

FLORA LICHTMAN: We asked our listeners to weigh in on this topic and we got many, many calls. People had a lot of thoughts and feelings about this, which I’m sure will not surprise you two because you work in this field. Let’s go to Maggie in Montana.

SPEAKER 4: I wanted to tell you that I was a truck driver for a little more than seven years. And I was shopping one day and I had some vitamins on sale, so I picked them up. And it turned out that they really made a difference in my performance, my ability to stay with the job and have physical energy. And that was– CoQ10 was the unusual item in there. And I want to make sure that I’m not ill-advising my friends.

FLORA LICHTMAN: C-o-Q10 or CoQ10, I’ve heard it called. Pieter, what do we about this supplement?

PIETER COHEN: Well, like many supplements, there’s a very important role for this in modern medicine. In this case, it’s a very important enzyme that’s at the cornerstone of how we generate energy in the body and the mitochondria. And some people– it’s rare but have genetic disorders that don’t make enough coenzyme Q10. And in those situations, it’s a cornerstone of treatment. Now, it doesn’t always work, but it’s certainly what should be tried first.

It’s that utility that then leads to interest in using it in other situations. And, for one, it’s been studied extensively for people who have muscle aches after taking common cholesterol medications, statins. And, in that case, it’s found not to be particularly effective. And I’m not aware of other strong evidence to suggest that healthy people, who don’t have these rare genetic disorders, would have great benefit from coenzyme Q10, but that doesn’t stop the supplement industry from being able to promote it for a variety of reasons.

FLORA LICHTMAN: I want to dig in a little bit on this because, Pieter, you said you don’t a lot of good evidence to back up the idea that it will help healthy people. And that seems common for a lot of supplements. Is that because we haven’t done enough research into supplements or is it because scientists have done research into supplements and actually it just doesn’t support being helpful.

PIETER COHEN: It’s a combination of both. In some areas there’s extensive research. So a good example of that is a multivitamin. So we have very well-conducted, large, randomized controlled trials showing that multivitamins really don’t help much, unless people have vitamin deficiencies or need them–

FLORA LICHTMAN: Do not help much.

PIETER COHEN: Right. But they also don’t hurt. So they’re not going to be causing cancer or increasing risk of heart disease. They’re pretty neutral. Now, with a majority of other supplements, they haven’t been studied in large trials. And there’s no incentive to at this point because when the industry can market products directly to consumers, which, as I mentioned, I’m a fan of having access, that means that the manufacturers don’t have incentive to do the large studies to sort out what works and what doesn’t work, particularly because the manufacturers can also advertise their products with all sorts of claims, such that it will help with everything from brain health, to the immune system, to giving you more energy without having to prove that in human clinical trials.

COLLEEN DERKATCH: And they’re also limited to the types of claims they can make. So they can make structure claims. They can make claims about supporting health without making disease claims. And I think that’s a really important distinction because then you can kind of say anything. What I found is that people just translate them in their own minds and so they’ll see “support sleep” on a bottle of melatonin and they’ll translate that to treats insomnia.

FLORA LICHTMAN: Right. I want to bring in another listener who has his own experience with this subject. He wrote the nutrition curriculum at Yale Medical School.

SPEAKER 5: This is D. Barry Boyd. I am a physician oncologist. I would avoid the use of very high dose supplements. One classic one is B12. And people are completely unaware of this, including physicians, that B12 has been linked, at higher doses, to a higher risk of lung cancers. And why would that be? It activates cell growth, cell replication, and, as a result, you end up raising the risk of diseases like lung cancer and is very easy to give it because you think it’s great for fatigue or other reasons. Those are not appropriate approaches to using B12 in very high doses.

FLORA LICHTMAN: I would love to hear what you all think of this. I mean, I’ve had many doctors offering me a B12 shot.

PIETER COHEN: Right. Well, I think this is a great example of how vitamins and minerals are active in the human body. And a small amount, which might be helpful, could lead to some benefit, if someone is deficient in the vitamin or under the mineral. But at higher dosages, you’re pretty much, with all the vitamins and minerals, eventually going to run into trouble. And that’s a problem with how these products are marketed. Because they’re presumed safe, basically by Congress defining them as safe, it gives the impression to consumers that if a little bit of a vitamin is good, then a lot must be better. And that, unfortunately, is inaccurate.

FLORA LICHTMAN: I mean– but many of the supplements you see that are not multivitamins, but just one compound, one mineral will say this gives you 453% of your daily value. How do I interpret that number? Is that real? And is it a good thing?

PIETER COHEN: Right. So I think that gets to another issue that we haven’t talked about yet, which is manufacturing problems and manufacturing control, quality control in the supplement industry. This is a very serious problem. And, in fact, I really wouldn’t trust most of that information that I see on the label.

We did a study of melatonin gummies to see how did the actual quantity of melatonin in the gummies compare to the labeled amount of melatonin. And what we found was really surprising. I was expecting to find variability and I thought some manufacturers might have not included enough melatonin. But, in fact, it was the opposite, really. We found that there was much more melatonin in most of the gummies than expected or than listed on the label–

FLORA LICHTMAN: Wow.

PIETER COHEN: –and sometimes two or three times more. So this is the situation where consumers really can’t get a straight story about what’s in the supplement just by reading the labels. And that has to do with very profound problems in manufacturing a supplement.

FLORA LICHTMAN: Have you found ingredients that don’t even belong there.

PIETER COHEN: Yes. So we’ve done many studies looking deeply at what’s actually in the pills. And in the melatonin study we did, we found CBD. And CBD–

FLORA LICHTMAN: Really.

PIETER COHEN: –should not be sold as a dietary supplement. So that’s an example of finding other things. But we’ve also found in many other studies that we have, in the supplement supply in the United States, chemicals and pharmaceutical drugs that might be approved or not even approved in other countries are appearing in the United States in dietary supplements.

FLORA LICHTMAN: We’ve talked about the shortfalls of supplements and some of the risks. Is there promise in the supplement world to actually develop new, effective treatments?

PIETER COHEN: Well, I think that the problem is– unfortunately, the situation is designed such that since you can go and start selling products without having done the research, it doesn’t encourage innovation. So that’s going to be a challenge for– in the future– is can we create a situation where consumers have access to supplements, which I believe is important, but, at the same time, we incentivize good science and research to find out which ones can benefit human health.

COLLEEN DERKATCH: Yeah, I agree. And I think, for me, a lot of it comes to legislation. We can’t be sure about what is in supplements because supplement manufacturers are not required to investigate that. Years ago in Canada, our CBC, the national broadcaster, did a very hilarious and notorious investigation where they got approval to sell a homeopathic sleep aid from Health Canada by literally pouring tap water into a bottle, photocopying a couple of pages of a homeopathy textbook, and creating a marketing campaign. And they got a natural health product number to sell that product legally in Canada as a sleep aid for children. And, to me, that shows that the biggest hole, I think, is that legislation isn’t requiring manufacturers to guarantee the safety and efficacy of their products. And consumers don’t know that because they go to their local pharmacy, which they trust, and they see these bottles on the shelf next to products like Tylenol Cold and Flu and other products that are tested for safety. And so people believe that the bottles contain what they say they contain and will do what they say they do. But we know that’s not true.

FLORA LICHTMAN: Thank you both for this conversation.

COLLEEN DERKATCH: Thank you.

PIETER COHEN: Thanks for having us.

FLORA LICHTMAN: Dr. Pieter Cohen, head of the supplement research program, associate professor of Medicine at Harvard Medical School, and internist at the Cambridge Health Alliance based in Somerville, Massachusetts. And Dr. Colleen Derkatch, author of Why Wellness Sells: Natural Health in a Pharmaceutical Culture and professor of rhetoric at Toronto Metropolitan University.

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