Age Later: Rethinking the Science of Longevity

Welcome back to the podcast. Today we are tackling a question that might fundamentally change how you think about getting older.

That's right, we are asking what would happen if modern medicine stopped playing an endless game of whack-a-mole with the big four diseases of aging, heart disease, cancer, diabetes, and Alzheimer's, and instead targeted their shared root cause. It sounds like science fiction, but that is exactly what Dr. Nir Barzilai proposes in his book, Age Later.

It really does sound wild, Marcus, but Barzilai is a pioneer in geroscience and the founding Director of the Institute for Aging Research at the Albert Einstein College of Medicine. His ultimate goal isn't just extending our lifespan to 120 so we can linger as frail patients. He wants to maximize our healthspan, coining the phrase, die young at a very old age.

I love that phrase. He calls this the longevity dividend, a state where super-agers live 20 to 30 more healthy years than average people, and usually only experience sickness for a brief window at the very end. But how they get there is the fascinating part, especially when you look at the Blue Zone myth.

Exactly, because popular culture loves the Blue Zone idea, telling us that if we just eat enough plants, have a strong community, and walk everywhere, we will easily hit 100. But Barzilai studied roughly 750 Ashkenazi Jewish centenarians over multiple decades, and he found they routinely broke every rule of healthy living.

It is honestly hilarious to read about. Nearly sixty percent of the men and thirty percent of the women in his study were long-term smokers. Many were significantly overweight and rarely exercised, which leads to this amazing anecdote in the book about a 108-year-old woman named Helen.

Oh, the Helen story is the best part. She had been smoking heavily for 95 years. When Dr. Barzilai asked her if anyone had ever told her to stop smoking, she just laughed and said the doctors who told her to stop smoking are all dead now.

That is incredible. It really highlights his core finding, which is that exceptional longevity, like living past 100, is predominantly driven by protective genetic mutations, or super genes. Lifestyle matters tremendously for getting you to 80 or 90, but to hit 105, you basically need the genetic lottery ticket.

And if you have that ticket, the results are absolutely staggering. Take Lilly Port, another centenarian in his study who lived to 107. Well into her 90s, she climbed Machu Picchu. In her 100s, she was still traveling to the Galapagos, Singapore, and the Alps, and scaling the stairs of her New York home 65 times a day.

That makes me feel incredibly lazy. But Barzilai's interest in this actually started way earlier, right? The book mentions he had a realization at age 13 while walking with his grandfather, who was only 67 at the time but bald, obese, and moving incredibly slowly.

Yes, that was his lightbulb moment. He realized that chronological age and biological age are two completely different things. That sparked his lifelong quest to figure out the specific cellular mechanisms found in these super-agers, and some of those mechanisms completely contradict modern bio-hacking trends.

You mean the growth hormone paradox? A lot of people today inject Human Growth Hormone to try and feel young. But Barzilai's centenarians actually have incredibly low levels of growth hormone, and that lowered IGF-1 pathway is highly protective against aging.

Spot on. They also have specific mutations, like the CETP gene, which gives them unusually high levels of protective HDL cholesterol. Plus they have elevated levels of Mitochondrial-Derived Peptides, which protect against cellular breakdown. But since we don't all have those genes, what does Age Later suggest the rest of us do?

That is where things transition from genetics to gerotherapeutics, which are basically anti-aging drugs. Barzilai wants to mimic these genetic effects using a 60-year-old generic diabetes medication called Metformin. It literally costs pennies a pill.

It is wild that the star of the show is so cheap and common. Massive epidemiological studies, like the UKPDS, showed that diabetics taking Metformin actually lived longer and had fewer cardiovascular events than non-diabetics who weren't taking it. It addresses multiple hallmarks of aging all at once.

That data led Barzilai to spearhead the TAME Trial, or Targeting Aging with Metformin. That is an unprecedented clinical trial spanning 14 US institutions and involving three thousand adults aged 65 to 79.

The science is cool, but the political goal of the TAME trial is what really fascinated me. Currently, the FDA does not recognize aging as a disease. Because of that, pharmaceutical companies cannot develop or market drugs specifically targeted for aging.

So TAME is designed to prove that a single drug can delay a whole cluster of age-related diseases, like cancer, heart disease, and dementia, simultaneously. If they succeed, it provides a proof-of-concept that forces the FDA to give aging a treatable indication, opening the floodgates for anti-aging biotech.

It is a brilliant strategy, but the book isn't without its critics. Medical reviewers note that while the book reads like having a glass of wine with an enthusiastic scientist, it can gloss over the intense, frustrating complexity of aging biology, making it sound like radical lifespan extension is just around the corner.

Yeah, and Barzilai himself admits to a fascinating data problem called the time bias dilemma. If a drug like Metformin successfully pushes back mortality, it might temporarily look like it causes Alzheimer's in the data.

Simply because it keeps people alive long enough to eventually get Alzheimer's at age 90, instead of dying of a heart attack at 75. It is a grim reality, but it shows just how incredibly complex this field of research really is.

He also has commercial conflicts, devoting text to private ventures he is involved in, like CohBar. But he argues academic research moves too slowly, so scientists rely on private biotech funding to get therapies to the public before they die of old age themselves. It really begs the question of whether older adults should be taking Metformin off-label right now, or waiting for those TAME trial results.

It is the ultimate question, and one we will be watching closely as the science evolves. Age Later is a highly optimistic, eye-opening read for anyone interested in why we age and how we might soon control it. Thanks for tuning in to our deep dive, and we'll catch you next time.