Early-stage high-grade tumours found in people with no symptoms
Once a year
Not once every five
Who is David Karow
The annual physical is a hundred years behind
David Karow is a radiologist — University of Michigan for medical school, then diagnostic and interventional radiology at UCLA’s Ronald Reagan Medical Center. By his own account he spent those years in sick care: reading scans of end-stage cancer, end-stage cardiovascular disease, end-stage dementia.
His critique of routine medicine is the sharpest we heard on the quest, and it is specific rather than rhetorical. The physical exam every one of us has had — stethoscope, reflex hammer, tongue depressor — is built entirely on signs of end-stage disease. Yellowing in the eyes means the liver has already failed. An aneurysm you can feel through the abdomen is already far past the point of easy treatment. “The whole idea behind the annual physical exam is really a hundred years behind.”
He saw an alternative being built at Human Longevity in San Diego, joined as a consultant, and built the entire imaging programme there. The approach stacks whole-body MRI on top of whole genome sequencing, blood biomarkers and wearable data — around 150 gigabytes per person — and reads them together.
One of the first clients through the programme was a former Nobel laureate and a friend of Craig Venter, who turned out to have an early-stage mediastinal lymphoma — a cancer almost always caught late. He was treated, and was still alive eight years later. In roughly one in fifty clients they find an early-stage high-grade tumour nobody suspected.
The line that stayed with us is how he describes the shift in his own job: “Instead of treating disease, I’m going to treat risk.” And underneath it, an argument that cuts against most of the longevity industry — that biological age, not genetic predisposition, is the number one risk factor for nearly everything, and that it is modifiable without exotic drugs.
Early detectionWhole-body MRIHealth spanPrevention
San Diego · May 2024
San Diego, after the scan
Where we met
We had met David before, diving off boating platforms into the bay in San Diego. This time he was reading Marek’s results. The interview happens immediately after the imaging review — Marek visibly relieved, David explaining what the scan could and could not say. It is the only interview on the quest conducted minutes after the person asking the questions had been through the machine himself.
Michigan, then UCLA
Training
Medical school and radiology — years spent reading end-stage disease.
Human Longevity, San Diego
~2017 onward
Brought in as a consultant; built the whole imaging programme.
San Diego
May 2024
Marek’s whole-body MRI, and this conversation straight afterwards.
“Whatever we find, there’s not going to be that much that will change in the next year. Whereas if you wait another five years — a lot can happen in five years.”
— David Karow, San Diego
On the quest
At the clinic
San Diego, May 2024. The conversation took place straight after Marek’s imaging review — his first whole-body MRI in 48 years.
In his words
Bleeding edge, not lunatic edge
“Instead of treating disease, I’m going to treat risk.”
David Karow · San Diego, May 2024
The whole idea behind the annual physical exam is really a hundred years behind.
David Karow
You can never outrun or out-exercise poor nutrition.
David Karow
You might lie, I might lie, your physician might lie. The data doesn’t lie.
David Karow
It’s not a foregone conclusion that you should spend the last five or ten years of your life in a nursing home.
David Karow
In his own words
Straight from the interview
From the conversation in San Diego — the six levers he says are in your control, what his own scan found, and the warning he wanted to leave us with.
The six levers
Rather than a supplement list, he names six things he considers modifiable and worth measuring: mitochondrial efficiency, insulin sensitivity, inflammation, accumulated toxins, hormone levels and oxidative stress. His claim is that centenarians did not win a genetic lottery — their own siblings often died at seventy — they found ways to move those six.
“Those six things, those are the hallmarks of ageing.”
San Diego · from the interview
What his own data told him
He went through the same programme. It found gut inflammation and a severe dairy and casein allergy he had lived with all his life without knowing. An elimination diet fixed the nausea and the malabsorption. Then the body-composition data told him something he did not want to hear: running seven days a week had left him with mild osteopenia and sarcopenia.
“Honestly, when I did that elimination diet, I never felt better.”
San Diego · from the interview
His warning to us
Asked what he wished for the rest of the quest, he said keep an open mind — and then, pointedly, be sceptical. His worry is that a focus on unproven elixirs both misleads audiences and buries the evidence that biological age is genuinely modifiable right now.
LinkedIn still to be confirmed. ⚠ His affiliation is given here as it stood at the May 2024 interview — Human Longevity has seen departures since (Julie Chen has moved to Radence), so this needs checking before it is treated as current.
From the conversation
David Karow, in his words
Video interview
The video interview is coming. Recorded interviews go live after the launch of the film & series Live Beyond.
From the conversation in San Diego, May 2024, recorded immediately after Marek’s imaging review at Human Longevity. Lightly edited for readability.
On why once a year, not once every five
David Karow“Whatever we find, there’s not going to be that much that will change in the next year. So you come through a little anxious, but more or less got a clean bill of health. And in one year we’ll do whole-body MRI again, we’ll re-annotate your genome, we’ll look at your blood work. No matter what process starts between now and next year, it can’t be all that dramatic. Whereas if you wait another five years — a tumour might start the day after your testing, and in five years that becomes a late-stage tumour. A week from now, we’d catch it early, when it’s curable. It’s the same reason women get mammograms not every ten years, but once a year.”
On leaving sick care
David Karow“Most medical school training, even today, is focused on end-stage disease. The superficial physical exam you get at your primary care doctor — the stethoscope, the reflex hammer, the tongue depressor — that’s built on end-stage disease. If you have yellowing in the eyes, you already have end-stage liver failure. There’s nothing you can do about that. If you can palpate an aneurysm in your abdomen, it’s way far along for treatment. The whole idea behind the annual physical exam is really a hundred years behind.”
Marek Piotrowski“So actually you wanted to get from being a doctor to being a doctor with superpowers.”
David Karow“That’s a decent way of putting it. As doctors we’d probably speak in more humble terms. But it’s the idea that instead of treating disease, I’m going to treat risk.”
On age being the risk factor
David Karow“Even a terrible disease like Huntington’s or ALS — Lou Gehrig’s disease — the number one risk factor is not your genetic predisposition, it’s your age. Nobody gets Lou Gehrig’s at thirty. Almost nobody gets Huntington’s at thirty. You get it in your fifties or sixties. Your biologic age is your most important risk factor. And we know we can modify your biologic age.”
On what his own results changed
David Karow“I learned right away that I had a pretty severe allergy to dairy and casein, and I had no idea — all my life a big dairy consumer. As soon as I got rid of dairy and some other things, my gut health got better, my inflammation went down, I didn’t wake up with nausea. I did an elimination diet, which sounds horrible, and honestly, I never felt better. Then I slowly added things back, methodically, to find out what was actually a problem.”
David Karow“Once I looked at all the data — body composition, VO2 max — I’m like, geez, this running seven days a week, actually not very healthy. I had a little osteopenia, a little sarcopenia. So more strength training, more biking, more swimming, more yoga, more balance and flexibility.”
On the word “biohacker”
Marek Piotrowski“So you became a full-time biohacker for yourself.”
David Karow“A little bit, but I don’t like the word biohacker — it comes across as a little superficial. I think I became a full-time user of data. Our car has ten thousand sensors. All our financial decisions are data-driven. Why shouldn’t we be using data for our own health? You might lie, I might lie, your physician might lie. The data doesn’t lie.”
His message to Aleksander’s generation
David Karow“If I’m being fanciful I’ll say there’s an opportunity for someone like Alek to live forever — but I don’t quite see that right now. I think that’s missing the mark. What we’re really about is health span. No matter how long you’re on this planet — seventy years, ninety, a hundred and thirty — we want you living your fullest potential during those years. It’s not a foregone conclusion that you should spend the last five or ten years of your life, or even the last year, in a nursing home in bed. It doesn’t have to be that way.”
His wish for the quest
David Karow“Keep an open mind. We pride ourselves on being on the bleeding edge, but not the lunatic edge. Be sceptical of some of the wild claims, because it’s dangerous for two reasons. One, it gives your audience the idea that the only way to achieve longevity is through unproven elixirs, potions, drugs. And the other casualty is that it ignores the whole body of evidence that biologic age and inflammation and mitochondrial efficiency are modifiable and in your control. If you just focus on that, you can do way more for your health span than with any of these unproven things.”
More passages from the full interview will be published here.
Continue the quest
More minds on the quest
David Karow anchors The Bridge of Prevention, with a strong pull into Longevity Basics — his own turnaround was food and training, not pharmacology.
