Hi {{ first_name| strip | default: "there" }},

There are supplements on Amazon right now labeled "tejocote root" that contains yellow oleander. Yellow oleander has cardiac glycosides. Those stop your heart.

The FDA told the companies to recall. The companies said no. The products are still for sale.

I take supplements. I recommend them to most of my patients. Several of my longevity protocols depend on them. So this is not an anti-supplement piece. But I dug into every major study on supplement contamination, and today I want to highlight what every user of supplements needs to know.

In 1994, Congress passed DSHEA, which classified supplements as food, not drugs. This is what is behind the disclaimer, "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease".

One vote, one reclassification, and an entire industry could sell products with no pre-market approval, no pre-market testing, and no mandatory proof that anything on the label was actually in the bottle.

The FDA cannot review a supplement before it hits your shelf. They can only respond after someone gets hurt. And by "respond," I mean ask the company to recall. Companies can still refuse 🤔.

Since then, the industry went from about 4,000 products to over 80,000. The market is now worth over $60 billion domestically. The regulatory framework was designed for a fraction of that.

Supplements are less regulated than food coloring. The artificial dyes in candy undergo stricter oversight than the ashwagandha capsule you bought last week.

The NIH's Drug-Induced Liver Injury Network (DILIN) tested 272 herbal and dietary supplements that had been linked to liver injuries. They used ultra-high-performance liquid chromatography and DNA barcoding.

51% were mislabeled.

Not "slightly off." Contents just did not match the label.

The same DILIN data shows supplement-caused liver injury nearly tripled in a decade: 7% of all drug-induced liver cases in 2005, 20% by 2014. In parts of Asia, herbal and dietary supplements account for 27% to 62% of all drug-induced liver injury cases, far exceeding the US rate.

A landmark study in JAMA Network Open analyzed FDA data from 2007 to 2016. They found 776 adulterated supplements from 146 companies.

Weight loss supplements: 85% of flagged products contained sibutramine, pulled from the market in 2010 for causing heart attacks and strokes. Banned for 16 years. Still in supplements today.

Sexual enhancement: 47% OTC supplements contained hidden sildenafil or tadalafil (so that’s why they work…). If you're on nitrate medications for a heart condition and unknowingly take sildenafil, your blood pressure can crater. People have died from this interaction.

Muscle building: 89% supplements tested contained synthetic steroids or steroid-like compounds. Some of which had never been tested in humans.

And: 67.9% of products caught once and recalled were found to contain entirely new undeclared drugs when tested again later. The companies didn't stop adulterating. They just switched ingredients.

Based on a comprehensive review in Free Radical Research and additional studies:

And even when the label is accurate to what’s inside the bottle, some of the most recommended supplements in the wellness space have known risks of liver damage.

Green tea extract: More than 100 case reports of liver injury, including liver transplants and at least one death. The culprit is EGCG, and toxicity shows up at doses as low as 140mg per day. France and Spain already pulled it from their markets years ago.

Ashwagandha: The internet's favorite adaptogen now has liver injury cases from Japan, Iceland, India, and the US. Presents as cholestatic hepatitis. Can progress to liver failure in people with pre-existing liver disease. I'm watching this one closely given its extreme popularity.

Also in the DILIN database with documented hepatotoxicity: Garcinia cambogia, kratom, black cohosh, valerian, red yeast rice, and Fo-Ti.

If you're optimizing for healthspan, you're probably taking 5 to 15 supplements daily (I’m guilty of this!). Each one is a separate bet on quality. And because these products accumulate over months and years, the damage from low-grade contamination is the kind you don't feel until it's a problem.

Lead accumulates in bone. Heavy metals are stubborn. That protein shake you've been drinking for three years? It might be delivering a slow, steady dose of lead with the whey.

And if you see "Pharmaceutical grade" on a supplement bottle? That’s legally meaningless because there’s no regulated definition.

The NEJM estimated 23,000 ER visits per year from supplement adverse events. The FDA estimates 50,000 total annually. Both are probably significant underestimates.

Only about 2% of supplement adverse events actually get reported to the FDA. Most people who get sick from a supplement don't connect the dots, don't know MedWatch exists, or don't think to report it.

When a patient walks in with a bag of 20 supplement bottles (this happens more than you'd think), here's the framework I use. Same one I apply to my own stack.

Every supplement should be tied to a lab result, a specific clinical goal, or biomarkers you're tracking. "I heard it was good" doesn't count. Neither does "I saw it on TikTok." More bottles = more risk.

I get many supplement samples given my line of work, and in a recent purge I tossed about 20 brands’ worth. Once you know the basics of screening supplements, you’ll be able to audit your cabinet too.

Three organizations I trust:

Companies have been caught faking certification seals. Go to the certifier's website. Search for the specific product. If it's not there, the seal is decoration.

Anything marketed for weight loss, sexual enhancement, or muscle building gets maximum skepticism. If the promise sounds like a pharmaceutical drug ("rapid weight loss," "natural Viagra," "enhanced performance"), the product probably contains one.

Also: anything from random marketplace sellers on Amazon, Etsy, or eBay. The yellow oleander products were all marketplace sellers. No brand accountability means high consumer risk.

Before adding any supplement, you can check:

Five minutes of checking can avoid massive consequences.

Green tea extract. Ashwagandha. Kratom. Garcinia cambogia. All have documented liver injury in the medical literature. Popularity doesn't correlate with safety.

When a supplement trends on social media, supply chains don't suddenly produce more high-quality raw material. They produce more product. Think about where that extra material comes from.

Most patients don't volunteer their full supplement list. They mention the prescriptions, skip the 12 bottles on the nightstand. In my practice, I need to see the exact brands to check interactions and flag risks.

If something goes wrong, report to FDA MedWatch. Only 2% of events get reported. Your report might be the data point that triggers a recall.

Before buying any supplement:

Brands I personally use and trust

I haven't vetted every supplement brand out there, and there are certainly other great ones. But these are brands I personally use and trust enough to keep in my own rotation:

• Thorne. NSF Certified for Sport, publishes batch-specific Certificates of Analysis, and lets you look up test results by lot number.
• Pure Encapsulations. Hypoallergenic formulations, GMP certified, independently tested. Great option if you have food sensitivities or want minimal fillers.
• Nordic Naturals. My go-to for omega-3s. Third-party tested for purity, potency, and freshness. Friends of the Sea certified.
• Carlson's. Another strong fish oil option. FDA-regulated facility, IFOS certified, potency and purity tested.
• Sport Research. Non-GMO Project Verified, third-party tested. Good value for staples like vitamin D and omega-3s.
• NOW Foods. One of the largest GMP-certified manufacturers. Extensive in-house and third-party testing at accessible price points.
• Double Wood Supplements. Third-party tested, US-manufactured. Carries some of the harder-to-find compounds (like NMN and berberine) at reasonable prices.
• Life Extension. Extensive third-party testing with published COAs. They fund and cite their own clinical research, which I appreciate even when I don't always agree with their dosing.
• Momentous. NSF Certified for Sport across their full line. Transparent sourcing. Their omega-3 and creatine are solid.

These are starting points, not an exhaustive list. The vetting checklist above works for any brand. If your preferred brand passes those checks, it's probably fine. The goal isn't brand loyalty; it's evidence that what's on the label is actually in the bottle.

I started this expecting to write a quick "how to pick good supplements" guide. What I found was a system built in 1994 for 4,000 products now overseeing 80,000, with enforcement that depends on companies policing themselves and consumers reporting problems they often don't even recognize.

Supplements can be useful. I take them and recommend them frequently. GlyNAC, creatine, vitamin D, omega-3s; these are all part of protocols I believe in. But the infrastructure around them has not kept up with how we use them.

Until it does, the burden of quality assurance is on you. That shouldn't be how it works, but it is. So be the most annoyingly skeptical person in the supplement aisle. Your future self will thank you.

Keep learning,

Hillary Lin, MD

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I filmed this episode a few months ago and it’s even more important now that I’ve dug into supplement quality. We go deep on how heavy metals accumulate, what the actual testing options look like (spoiler: most standard panels miss them), and what detox protocols are supported by evidence vs. which ones are expensive nonsense.

👉 Watch on YouTube (40 min)

Keep learning,

Hillary Lin, MD

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