Supplement bottles on clean surface

The Worst Conversation
of My Life Happened in Amsterdam.

500kg of spermidine. A freezing office. And a choice: blame the shipping line, or own it.

Supplement shelf
Chapter 1

Before NMN, there was everything else.

I wasn't a brand owner back then. I was a buyer — sourcing raw ingredients from Chinese manufacturers for European clients. My obsession was antioxidants. I touched nearly every major category.

S
SpermidineAutophagy

Wheat germ extract. The molecule that taught me supply chains can break anywhere.

Benefits

Induces autophagy — the body's cellular cleanup process. Linked to cardiovascular health, cognitive function, and longevity in human clinical studies.

Dosage

Clinical trials: 1.2–3.3 mg/day for cognitive benefits. Safe up to 40 mg/day short-term. Food sources: wheat germ, aged cheese, soybeans.

E
ErgothioneineLongevity Vitamin

Mushroom-derived. First product I ever sent to an independent lab.

Benefits

Potent antioxidant with a unique cellular transporter (OCTN1). Protects mitochondria, supports cognitive health, and reduces oxidative stress and inflammation.

Dosage

Typical supplement dose: 5–25 mg/day. Food sources: shiitake, oyster, and king oyster mushrooms. Heat-stable — cooking does not destroy it.

S
SilymarinLiver Health

Milk thistle extract. Europe's best-selling botanical — and one of the most counterfeited.

Benefits

Liver protection and regeneration. Antioxidant and anti-inflammatory. The most clinically studied botanical for liver health worldwide.

Dosage

Clinical standard: 420 mg/day (split into 3 × 140 mg), standardized to 70–80% silymarin content.

B
BetaineMethyl Donor

Also called TMG. Cheap to make, easy to cut. I've seen it all.

Benefits

Methyl donor — supports homocysteine reduction, liver health, and cellular hydration. May enhance muscular endurance during high-volume training.

Dosage

General health: 1.5–3 g/day. Homocysteine management: 3–6 g/day. Naturally abundant in beets, spinach, and quinoa.

F
FisetinSenolytic

The newcomer. Strawberry-derived. Early data is fascinating — early adulteration, too.

Benefits

The most promising natural senolytic — selectively clears senescent cells. Under active investigation at Mayo Clinic for healthy aging applications.

Dosage

Typical supplement dose: 100–500 mg/day. No official RDA — human clinical trials are ongoing. Found naturally in strawberries and persimmons.

I learned how supply chains worked, where they bent, and where they broke. The pattern was always the same: a beautiful COA, a confident supplier, a happy client — and occasionally, a lab result that didn't match.

Amsterdam canal in winter
Chapter 2

Amsterdam. Winter.
The shipment failed. The client stayed.

K
Kai
?
Client, NL
S
SupplierChina

Late afternoon. The canals were grey and motionless. By 4 PM the sun was already gone. I was sitting in my client's office — a Dutch man in his sixties who had been in the supplement business longer than I'd been alive.

Between us, on the table: his coffee cup, empty. Mine, untouched. 500 kilograms of spermidine, two weeks late. Spoiled in transit. Improper storage. A shipment worth more than I care to remember.

I was the youngest person in that room. The only Chinese. The one with the most to prove. I was not just representing my company — I was carrying the weight of every stereotype about Chinese suppliers. Every mistake confirmed their assumptions. Every silence felt like an admission.

“So,” he said. Just that one word.

I had nothing. My English was fine for emails. But sitting across from a man I respected, with nothing good to say — the words wouldn't come. I could feel the heat crawling up my face. In Chinese we call it diu lian — losing face. I was losing it in a foreign country, in front of the one client I'd spent two years earning.

In this business, you get one chance. Sometimes none. Sitting in that chair, I knew: this was probably my last meeting with this man.

Then something happened that I didn't expect.

Our supplier — a Chinese factory we'd worked with for three years, who had never failed us — did not make excuses. They pulled stock from other clients' orders, re-routed within 48 hours, and got enough material moving to keep my client's production line alive.

I spent the next two weeks giving him daily updates. Not because I had good news. Because I wanted him to know I was still there. Still accountable. Not hiding.

After the shipment arrived, he asked me to stay for dinner.

“I've worked with many suppliers,” he told me, years later. “Most disappear when something goes wrong. You didn't.”

That man gave me a second chance. I was lucky — I know that. Most people don't get second chances. I got one because of two things: a supplier with real accountability, and a client willing to see the person behind the mistake. We're still friends today.

COA report
Chapter 3

After Amsterdam, I stopped trusting. I started testing.

I sent samples of everything — spermidine, ergothioneine, silymarin, betaine, fisetin — to independent labs. HPLC for purity. ICP-MS for heavy metals. Microbial panels for safety.

What came back was not one bad batch. It was a pattern — across categories, across suppliers, across countries.

What I found across 4 categories

×Ergothioneine: 52% purity. 48% maltodextrin.
×Silymarin: Label said 80% silymarin. Lab said 47%.
×Betaine: Cut with baking soda to inflate weight.
×Fisetin: 300mg on the label. 160mg in the capsule.

When I finally turned to NMN, I wasn't surprised. I was exhausted. 500mg on the label, 312mg in the capsule. The same game, different molecule.

That's when I stopped being a middleman. I built Mureen — not just for NMN, but for every category I'd watched fail. A brand where every batch gets tested, every result goes public, and nothing ships without passing the full panel.

Chapter 4

Three things I found — and couldn't unsee.

Half-empty supplement capsule
01

I bought a '99% pure' antioxidant. The lab said 52%.

Not NMN. This was ergothioneine — a European brand, beautiful packaging, €89 a bottle. HPLC showed the active compound was cut 48% with maltodextrin. The COA they sent? Tested the raw powder before blending. The finished capsule was a different story entirely.

Two identical-looking jars
02

A supplier charged me 3x for 'fermented.' It was chemically identical to synthetic.

This happened with spermidine. Premium story, premium price. I believed it for a year. Then I ran NMR spectroscopy. Same molecule. No biological difference. I had been passing a markup to my customers for nothing.

Supplier COAs on a desk
03

I asked 11 brands for their finished-product COA. Most couldn't produce one.

Not raw powder. Not a three-year-old certificate. A full-panel test on the capsule you'd actually receive. Silymarin, betaine, fisetin — same story across the board. Beautiful websites, confident claims, no finished-product testing. That was the moment I knew: if I wanted supplements I could trust, I'd have to build them myself.

Product lineup

The industry standard vs. Mureen.

Most brands

  • ×Test raw powder, not finished capsules
  • ×Fillers can be 30-40% of capsule weight
  • ×COAs are marketing, not accountability
  • ×Marketing budget > testing budget

Mureen

  • ✓Full panel on every finished batch
  • ✓Label matches what's in the capsule
  • ✓COAs published. No exceptions.
  • ✓We spend on labs, not Facebook ads.

Why we exist

Three things we do differently.

Testing

We test the finished product. Every batch. Every time.

Not the raw powder. Not a sample from three years ago. The capsule you receive — we ran a full panel on that batch before it left the facility.

Pricing

You pay for the molecule. Not the ad budget.

Some brands spend more on Facebook ads than on ingredients. We don't run ads. We spend on HPLC, ICP-MS, and microbial panels.

Transparency

If we can't prove it, we don't claim it.

No cherry-picked studies. No 'proprietary blend' hiding behind milligrams. Every COA is public. Every batch is traceable.

Product with COA

What our customers say.

I've taken supplements from many brands over the years. Mureen is the first one where I felt like they actually wanted me to verify their claims — not just trust them.

Verified Purchase

The transparency is what got me. Every COA is public. I showed it to my doctor. She was genuinely impressed.

Verified Purchase

Common questions.

How do I know your supplements are real?

We publish every Certificate of Analysis — full panel, no exceptions. HPLC purity, heavy metals, microbial.

Why are some supplements so cheap?

Fillers, untested ingredients, or low purity. Third-party testing costs money — and most brands skip it.

Which products do you carry?

We started with NMN. Spermidine and ergothioneine are in testing now. More categories coming — same standard, same transparency.

Are your supplements safe?

Every batch is tested for heavy metals, microbial contamination, and potency before it leaves the facility. We ship nothing that fails.

Supplements that do what they say.

Third-party tested. Full transparency. Fair pricing. Every category, every batch, every time.

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