My wife is the healthiest person I know – healthier than me in many ways. I don’t think her mom ever gave her sugar as a kid, she has the gut biome of a superhero. (How do I know? - I persuaded her to do every test I could find - 160 biomarkers, GI test, DNA sequencing and more)

So when she had some blood tests done not long after she had our daughter Ava – she got back results with flying colors. But she didn’t really feel superhero status. Her energy was off, her sleep was off. So around that time, I found out about Function Health. I’m a junkie for trying the latest fad and gadget or biohack to see if it holds any merit. Function Health lets you pay for a blood draw, and you get access to all 160+ biomarkers in your dashboard. It’s phenomenal. I’ve done it now 4 times. Annette got on the bus a little bit after me.

When she got her results back, her iron was normal (like always) but her ferritin — the number that tells you how much iron you actually have in storage — was low. She’d been trusting the headline number; the real story was in the number underneath it. So she researched what she could do, started taking a ferritin supplement for a few months to see if it would move the needle, and when she retested, it had moved back into normal range — and her energy levels were back to her superhero self.

I keep thinking about this, because Annette isn’t the only person whose “normal” test was hiding something.

You may know the name Bryan Johnson. He’s the tech founder who spends millions measuring every inch of his own biology, chasing a goal he sums up in two words: don’t die. The internet loves to pile on him, and some of it lands — he’s made himself a target by living so publicly. I like the guy, I think he’s funny and I admire anyone trying to better their health and sharing their journey with the rest of us.

For eleven years, Bryan’s ferritin was low. Eleven years. And for eleven years, standard care shrugged it off, because his hemoglobin — the headline iron number — looked fine. It wasn’t until he pushed, tested deeper, and biopsied his own stomach that he got the real answer: autoimmune gastritis, a condition where the immune system quietly attacks the stomach lining and blocks iron from getting in. In his own words, it was “never one problem. It was three, linked to one another.”

Whatever you think of the man, that’s the lesson. The data sat there for over a decade. Nobody went looking, because the surface looked fine.

When most of us get “iron” checked, we’re getting a snapshot — how much iron is floating in the blood at that moment. That number bounces around all day. Ferritin is different. Ferritin is the protein that stores iron. Think of it as the fuel actually in the tank, versus the gas gauge flickering at one red light. You can look fine in the moment and still be running on fumes.

Mayo Clinic even has a name for this: latent iron deficiency — when your ferritin is low but your hemoglobin hasn’t dropped yet. By the official line, you’re not “anemic.” But your stores are empty, and your body knows it, even when the lab summary doesn’t say so.

And it shows up as exactly the stuff we blame on everything else. Fatigue. Brain fog. Getting winded on the stairs. Lousy sleep. We call it stress, or age, or “just a busy season.” Sometimes it’s an empty iron tank.

The research points the same way. In a study of non-anemic women with unexplained fatigue, the ones with low iron stores who corrected them felt noticeably less tired than the ones who didn’t. Not because iron is magic — because it was the actual missing piece.

Now, the other direction matters too. Iron isn’t a “more is better” story. Too much stored iron carries its own risks. Which is the whole point: You want your numbers.

I used to believe in one-size-fits-all health. Eat this, avoid that, and everybody wins. I don’t anymore. The longer I live in my own body — and watch Annette live in hers — the more I’m convinced health is personal. Deeply personal. What impacts me might not touch you. The fix that gave her her energy back might do nothing for mine.

That’s not a reason to throw up your hands. It’s a reason to get curious. To gather your own data, and then learn what to do with it.

Ask for the number underneath. Next time you get bloodwork, don’t settle for “your iron’s normal.” Ask specifically for ferritin. It’s cheap and common — usually you just have to request it. Though Annette said some comments back to her were from women saying their doctor wasn’t willing to check that – thus why Function Health is so great.

Know your own baseline. One reading is a dot. Two readings are a line. Track it over time so you can see your trend, not just a single moment.

Don’t diagnose yourself from a slogan. Low ferritin, high ferritin, and “totally fine” can look the same from the outside. This is where you want a doctor who’ll actually dig — not one who stops at the headline. (Again: more iron isn’t automatically better.)

Still agree on the boring stuff. Even in a world where health is personal, a few things are close to universal. Eat real food, mostly unprocessed. Keep steady sleep and wake times. Get outside, into actual nature. Move your body in a world built for sitting. Stay away from the things that quietly poison you. Start there — then personalize.

Annette got her energy back not because she found a magic supplement, but because she stopped trusting the headline and went looking for the real story. Bryan Johnson —found his answer the same way, (despite spending $2 million+ year on his health) after eleven years nobody bothered to look.

You are not a reference range. You’re a person. Your data is worth chasing. And when you find it, the next move isn’t panic — it’s learning what to do about it, one honest number at a time.

What’s the number under your number? Maybe it’s time to ask.

-Jared

P.S. - My wife Baddie Crocker has a beautiful newsletter where she shares her perspectives on tending the land, recipes, women’s health and more.

P.S. - This newsletter does not provide medical advice. The content, such as graphics, images, text, and all other materials, are provided for reference and educational purposes only. The content is not meant to be complete or exhaustive or to be applicable to any specific individual's medical condition.

Here are links to things that have helped me improve my health:

Whoop - Track your HRV and REM Sleep

Function Health - Optimize Your Health via 160+ BioMarkers

Here are a few topics I think you’ll love if you haven’t checked them out before:

How to Breathe for Better Health

How to Supercharge Your Sleep

The Power of the Sauna