A friend asked me about AG1 this week. Turns out, that wasn't really the question.

He’s still climbing, hiking, active with his kids, logging ten hours of exercise a week. But fatigue was arriving earlier in the week than it used to. His DEXA scan was showing muscle mass declining year over year, slowly but consistently. His dietician had started recommending supplements. He'd never taken any and didn't know where to start, and he didn't trust most of what he was reading because half the people recommending products have financial ties to the companies making them.

What he was really asking was how to get ahead of something he could feel starting to slip, and whether any of the noise out there was worth listening to.

I'd been in the same place a few years back. Doing well by most measures, while being aware of something I could feel that was a bit off, but I couldn't quite diagnose.

The reason this is hard to name is that the changes are gradual enough to normalize. Testosterone declines by roughly 1% per year after age 30, often more rapidly under sustained stress. Muscle protein synthesis slows. Recovery takes a little longer. Fatigue arrives a little earlier. None of it feels like decline. It just feels like a slightly worse version of how you used to feel, which you eventually stop comparing to anything because the old baseline fades.

The muscle mass you have at fifty is largely a reflection of what you did in your thirties and forties. And what you have at sixty-five reflects what you do now. It seems there's no catching up, just compounding from wherever you're starting.

The instinct is to reach for supplements. It's a reasonable instinct. But it's a general solution applied to an unknown problem. Without knowing what's actually shifting in your body, you're guessing. And the supplement industry has been built almost entirely on selling guesswork, knowing people will never really know if the brand promise is delivered.

What changed it for me was starting a quarterly blood panel. Full hormones, inflammation markers, metabolic indicators. I went in wanting data. One quarter tells you where you are. Several quarters tell you what's actually moving, how fast, and whether what you're doing is working.

Stress has been high this past year: a new baby, a cross-country move, and building a business without a safety net. The body doesn't evaluate whether your stressors are justified. It just registers stress load. And sustained load shows up in the numbers, whether you feel it yet or not. Cortisol stays elevated. Elevated cortisol suppresses testosterone production, disrupts thyroid signaling, drives inflammation, and erodes sleep quality that would otherwise allow the system to recover.

You can be disciplined about all the right things and still have the underlying numbers moving in the wrong direction.

Seeing it in your own bloodwork is different from reading it in an article.

What I told my friend: the instinct to get ahead of it is right, but the sequence matters. Test first. Understand what's actually shifting and why. Then decide what intervention makes sense for your specific picture, not for a generic forty-year-old described in an Instagram ad. He's signing up for a full panel. I hope it works for him.

My next panel is a few weeks out. This conversation was also a reminder to show up to it, having actually moved the numbers. It forces accountability.

The supplement question isn't wrong. For me, it's just the second question.

The first one is simpler, and most of us have never actually answered it: Do you know what's happening in there?

If you have gone down this rabbit hole, hit reply. I'm curious what you've found works best for you.

Three things I'm doing between now and my next blood panel.

None of this is abstract for me right now. I have a five-week-old at home. The reason I care about what my bloodwork looks like at forty is partly about how I feel today, and partly about something further out: being able to keep up with my kids in ten or twenty years, being healthy enough to actually show up for their lives, meeting my grandkids if I'm lucky enough.

Four workouts, thirty minutes each. Regular moderate exercise lowers baseline cortisol over time, supports testosterone production, and directly counters the muscle mass decline that shows up on a DEXA scan. Four sessions this week.

Nothing caffeinated after 1 pm. Caffeine has a five to six-hour half-life. An afternoon coffee is still active at midnight, working against the sleep architecture that regulates cortisol and testosterone. The morning cup stays, everything after 1 pm is decaf.

Taxes done by Friday. The brain processes an unresolved future obligation the same way it processes a present threat, the same cortisol pathway, running quietly in the background, whether you're thinking about it or not. This has been sitting there since January. Getting it done is a stress intervention that happens to look like an admin task.

A note on sleep: the research points to it as the highest-leverage intervention, the thing that lets everything else actually work. I'm prioritizing it as much as I can. But with a five-week-old, a hard bedtime is the one commitment I can't honestly put on this list right now.

Small things stack. That's the whole idea.

See you next Sunday,

Eric

P.S. If my friend sounds like someone you know, feel free to forward this.