Science Corner 69 | Expert Interview: William Wallace - The Supplement Myths Hiding in Plain Sight

In this Science Corner interview, Jordan sits down with Dr. William Wallace, co-founder of Mechanism of Action, to work through some of the supplement industry's most persistent myths. There's too much ground covered to fit it all here, so what follows are a few of the highlights. For everything else, watch the video above.

Most supplement confusion comes from the wrong information repeated often enough that it starts to feel like fact. Dr. Wallace (per his request, we will call him Will) has spent a decade building supplements from the inside, running trials, formulating products, and navigating regulatory compliance.

He walked me through the myths he encounters most.

"Natural" Doesn't Mean Safe

Most people treat "natural" as a synonym for harmless. Will pushes back on that pretty hard.

"Natural is really just a marketing classification," he told me. "It tells you very little about something's regulatory status. It tells you very little about something chemically."

In 1990, a Belgian clinic introduced a Chinese herbal weight loss supplement that contained a sourcing error. The intended ingredient was Stephania tetrandra. What was actually included was Aristolochia fangchi, a similarly named plant that had been used in traditional Chinese medicine for over 2,500 years. More than 100 patients developed rapidly progressive nephropathy. Of the 39 who reached end-stage renal disease and underwent prophylactic removal of the kidneys and ureters, 18 were diagnosed with urothelial carcinoma, a cancer of the urinary tract. The compound responsible, aristolochic acid, is classified by the International Agency for Research on Cancer as a Group 1 human carcinogen. Nobody knew until this “natural” compound showed up in a supplement.

On the other end of the spectrum, roughly 90+% of supplemental vitamin C is believed to be synthetic, produced through microbial fermentation of corn-derived glucose. Your body processes it identically to the vitamin C found in food. The "synthetic" label means nothing here in terms of safety or function.

"Natural" describes a marketing category, not a chemical property or a safety profile.

The question isn't always where a compound came from. The question is what it does inside a biological system.

Supplements Are Regulated. Just Not Pre-Approved.

The claim that supplements are unregulated gets repeated constantly. It's not accurate.

Supplements are governed by the Dietary Supplement Health and Education Act, signed in 1994. Under that law and the rules that followed, manufacturers are bound by Good Manufacturing Practices, which mandate:

• Test incoming raw materials. Every manufacturer is required to verify what goes in before it goes into a product.

• Test outgoing finished products. The final product has to be tested before it ships.

• Maintain food safety and sanitation programs. These are mandates, not suggestions.

• Keep records the FDA can audit. The FDA has jurisdiction to come in and review all of it, and can pull products it deems an unreasonable risk of harm.

Where it gets complicated is pre-approval. A drug company has to prove safety and efficacy before a product reaches market. A supplement company does not. The FDA has to prove harm after the fact. Since 1994, the supplement industry has grown roughly 20-fold, and the FDA's auditing capacity has not kept pace. The agency has used its authority before, removing ephedra and DMAA from the market. But it cannot review every facility or every label with the frequency it originally committed to.

The regulatory framework exists, but the enforcement has gaps. Saying supplements are unregulated misses the first part entirely.

Shelf Placement Is Not a Quality Signal

CVS ran a third-party testing program on the supplements it was selling and published a report in 2019. Roughly 7% of 1,400 products were not meeting label claims, about one in 14. CVS pulled those products. The program also tested only one lot per product, meaning every subsequent manufacturing run was unverified.

As Will put it, "Retail placement is a distribution achievement. It's not a quality certification." Getting a product onto a major retailer's shelf requires meeting certain commercial and logistical thresholds. It does not require ongoing analytical testing. The procurement team evaluating a supplier is doing a commercial evaluation, not a scientific one.

Trusting the shelf means trusting the retailer's procurement department to function as analytical chemists. That is not what they are hired to do.

More Milligrams Is Not Better

Biology does not scale linearly with dose, and supplement marketing mostly ignores this.

Many nutrients follow a dose response curve that rises steeply, then levels off. There's a steep initial effect as the compound does its work, and then the curve flattens as the system saturates. Protein synthesis is a well-studied example. A 2018 analysis concluded that 0.4 grams per kilogram of body weight per meal is a reasonable target for maximizing muscle protein synthesis. Beyond that, the body oxidizes a greater share of the additional amino acids for energy rather than using them to build tissue. The returns don't disappear entirely, but they flatten considerably.

In some cases the curve flips. Vitamin A is essential for fetal development at normal doses and becomes harmful above 10,000 IU per day. Iron deficiency causes serious problems, and so does iron overload, which can damage tissue.

There's also a formulation issue worth knowing. It can be cheaper to put a large milligram count of a generic commodity ingredient on a label than to put in a smaller, well-absorbed dose in the right delivery format. A stabilized form of B12 at a lower dose may outperform a high-milligram generic that absorbs poorly. The number on the label is not the whole story.

Many nutrients have a ceiling. More past that ceiling is not optimization. In some cases, it's risk.

Form Matters. But Not As Much as Marketing Suggests.

Will's position on nutrient forms is that the differences are real, but routinely overstated.

Magnesium is his go-to example. Organic forms like magnesium glycinate are shown to absorb better than inorganic forms like magnesium oxide. This is true. It's also true that magnesium oxide has multiple clinical trials showing it can support magnesium status in people. It works. It's cheaper. For someone who tolerates it, it may be entirely adequate.

Folic acid is more complicated and more interesting. It's a synthetic oxidized form of folate not found in nature, and methylfolate is the active form the body uses. The mechanistic argument for preferring methylfolate is reasonable. And yet: a 1991 trial run across 33 centers in seven countries found that folic acid reduced neural tube defects by 72%. Since mandatory fortification began in the United States in 1998, neural tube defect rates have fallen by more than 30%. Will called it the most successful public health intervention in the history of natural product research applied at a population scale. That track record exists regardless of where someone lands on the methylfolate debate.

One Study Is One Puzzle Piece

Will and his wife have apparently been deep into jigsaw puzzles for the past few months, which gave him an analogy he used for how to read supplement research. A single study is one puzzle piece. You can see a color or an edge. You cannot look at one piece and describe what the finished image looks like.

The NAD precursor space is a useful real-world case. There are studies showing NMN and NR producing measurable improvements in submaximal exercise tests like the six-minute walk or sit-to-stand. Few of those findings have been replicated in different populations, and effect sizes in supplement research tend to shrink as studies get larger and run longer.

His framing for what a single study actually tells you: this was shown once, in this population, at this dose, with this specific compound. That is the accurate scope of interpretation. Anything broader requires more pieces.

Will’s Stack

I always end these conversations the same way. One supplement you cannot live without, and one flying under the radar.

• Creatine, 5 grams daily. His non-negotiable. He was straightforward about the neurological claims building around creatine, noting they are early stage and that nobody has demonstrated creatine actually reaches brain tissue in a clinically meaningful way. For physical performance, though, the evidence base is about as solid as anything in this space.

• Lithium orotate. His under-the-radar pick. Lithium has some of the most consistent epidemiological findings of any nutrient in the literature, and the mechanisms, as Will put it, are "intoxicating," which he acknowledged is a pointed word choice given lithium's known therapeutic window in clinical psychiatry. The supplemental case and safety profile via lithium orotate is still being built out, but he believes the potential for benefit in day-to-day functioning is real and underappreciated.

For the full conversation, including Will's thoughts on why the same supplement can produce strong results in one person and nothing in another, watch the video above.

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Personal note from Jordan

When two scientists get on a call with no real agenda, the conversation goes places it wouldn't otherwise. Will has spent a decade inside supplement formulation and regulatory compliance, and that kind of experience produces a different quality of opinion than you get from someone who has only read the literature.

The puzzle analogy was the moment I felt most at home in the conversation. I am a big jigsaw puzzle person too, and when Will mentioned he and his wife had been on a binge, it clicked. It's also just a good way to think about reading supplement research. One study is one piece. You can see a color or an edge, and that's about it.

Lithium orotate caught me off guard. I didn't know much about it going in, and I left wanting to know more. That doesn't happen every interview. The epidemiological data Will referenced is interesting, and I've been slowly working through it since we talked, however it is worth noting that the safety profile is still being established. There will probably be a Science Corner on it at some point.