My PhenoAge at 71: The Free Biological Age Score Hiding in Your Bloodwork
The short version: PhenoAge is a free biological age score you can calculate from nine markers on an ordinary blood test. I ran it on my own results. At 71, my PhenoAge is 55.6, and it dropped two years between my January and June blood tests.
When I started posting on Bryan Johnson’s Don’t Die app again, a 68-year-old member asked me a question within an hour that I couldn’t answer: “What’s your PhenoAge?”
I had never heard of it. If you haven’t either, you may already have everything you need to calculate yours.
What Is PhenoAge?
PhenoAge, short for “phenotypic age,” estimates how old your body is acting, not how many birthdays you’ve had. It was published in 2018 by Morgan Levine and her colleagues, then at Yale, in PLOS Medicine. They built it from U.S. national health survey data and then tested it on more than 11,000 adults, where it predicted death from all causes and from most major diseases better than calendar age alone.
What makes it special is that it doesn’t need a fancy test. It uses your age plus nine markers from a standard blood panel:
- Albumin
- Creatinine
- Fasting glucose
- C-reactive protein (CRP), a measure of inflammation
- Lymphocyte percentage
- Mean cell volume (MCV)
- Red cell distribution width (RDW)
- Alkaline phosphatase
- White blood cell count
The formula is published and free. Anyone can run it.
My PhenoAge at 71
I pulled the numbers from my two Function Health blood tests this year (that’s an affiliate link; I may earn a small commission at no extra cost to you) and ran them through the formula. Both draws were fasting.
| Blood test | My age | PhenoAge |
|---|---|---|
| January 2026 | 70.9 | 57.7 |
| June 2026 | 71.3 | 55.6 |
That’s roughly 16 years younger than my calendar age, and two years younger than it was in January.
How Does It Compare to My Function Health Biological Age?
Function Health gave me a biological age of 56 from the same June blood draw. Function uses its own formula across its much larger panel. PhenoAge uses just nine markers. Two different methods landed within half a year of each other, which gives me a lot more confidence that the number is real. It’s also why I didn’t take the Death Clock app’s guess very seriously.
What Moved My Score?
Between January and June, three markers improved the most:
- Inflammation dropped. My CRP went from 0.3 to below what the lab can measure (under 0.2 mg/L).
- Blood sugar fell. Fasting glucose went from 81 to 74 mg/dL.
- White blood cell count came down, from 7.5 to 6.0.
Inflammation and blood sugar carry a lot of weight in the formula, so seeing them improve together makes sense.
How Can You Find Your PhenoAge?
If you’ve had a standard blood panel that includes a complete blood count (CBC), a comprehensive metabolic panel and a high-sensitivity CRP, you probably already have all nine numbers. Search for a “PhenoAge calculator,” type them in, and you’ll have your score in a couple of minutes. Use a fasting glucose, or the result will be off.
What’s your PhenoAge? Tell me in the comments. I’m going to track mine every time I test.
You can see everything else I do in my protocols, follow my numbers on my tests and stats page, and check out my fitness routine.
Live long and prosper,
Gary
A note from Gary: I am not a doctor, and I am definitely not your doctor. I’m a 71-year-old running a public experiment on myself, and PhenoAge is an estimate from a published formula, not a diagnosis. Talk to your physician before changing anything based on your bloodwork.
These are products I use on my push to 200. I only put something on this list after I’ve tested it on myself. The links are affiliate links, which means I may earn a small commission at no cost to you.
See more products →
