What if the biggest risk factor for cancer, heart disease, and dementia isn't your genes, diet, or blood pressure but aging itself? Listen in as biogerontologist Dr. Matt Kaeberlein reveals how understanding the biology of aging could add not just years to our lives, but healthy decades, and why your dog might hold some of the most important clues.

In this episode, Therese Markow and Dr. Matt Kaeberlein discuss aging research. He explains that aging is characterized by damage accumulation and loss of resilience, leading to functional decline. Matt highlights the hallmarks of aging, such as deregulation of nutrient sensing and DNA damage, and the potential of interventions like rapamycin to slow aging. He notes that biological age is a significant risk factor for major diseases, and that understanding and addressing aging biology could significantly extend human lifespan. They also discuss the Dog Aging Project, with 55,000 participating dogs, which aims to uncover genetic and environmental factors influencing health and longevity in pets.

Key Takeaways:

• Our bodies are constantly being exposed to stress, and stress can move us out of the optimal zone of function. When we're young, we're very resilient and able to come back to optimal function. As we get older, we lose that resilience.

• When we slow aging in laboratory animals, we prevent the onset and progression of all of the major age-related functional declines and diseases simultaneously, because we've slowed biological aging. Based on what's possible in mice, it is estimated that we could potentially gain 2-3 additional decades of life if we can achieve this in humans.

• There is a genetic component to longevity; however, how big that genetic component is to longevity is hotly debated. The environment is also a large contributor.

"Biological age is the single greatest risk factor for nine of the top 10 killers in the United States, and it's not a small effect. The magnitude of effect from biological aging dwarfs all of the other risk factors combined…it's useful to appreciate how important biological age is to the risk of developing many of the chronic diseases and functional declines that limit quality and quantity of life for most people." — Dr. Matt Kaeberlein

Episode References:

• Dog Aging Project: https://dogagingproject.org/

• Dog Aging Institute: https://dogaginginstitute.org/

• Longevity for Dogs: https://www.youtube.com/@LongevityForDogs

Connect with Dr. Matt Kaeberlein:

Professional Bio: https://halo.dlmp.uw.edu/people/matt-kaeberlein/

Publications: https://pubmed.ncbi.nlm.nih.gov/?term=%22kaeberlein+m%22[author]

YouTube: https://www.youtube.com/@mkaeberlein

LinkedIn: https://www.linkedin.com/in/mkaeberlein/

Connect with Therese:

Website: www.criticallyspeaking.net

Bluesky: @CriticallySpeaking.bsky.social

Instagram: @criticallyspeakingpodcast

Email: theresemarkow@criticallyspeaking.net

Audio production by Turnkey Podcast Productions. You're the expert. Your podcast will prove it.

Peptides are being sold online as miracle fixes for energy, healing, and longevity—but what if the science behind them is shaky, or even dangerous?

In this episode, Therese Markow and Dr. Leigh Baxt pull back the curtain on the peptide craze, revealing what we really know (and don't know) about these heavily marketed "biohacks." They discuss the complexities and risks of unapproved peptides, which are often marketed for health enhancement. Dr. Baxt explains what peptides are and speaks to those drugs that are FDA-approved, like GLP-1 agonists and insulin, but also highlights the safety concerns of unapproved peptides, such as BPC-157 and TB-500, which lack appropriate clinical trial data and are often synthesized in unregulated labs. Dr. Baxt emphasizes the importance of proper clinical trial processes and regulatory oversight to ensure drug safety and efficacy.

Key Takeaways:

• A peptide is just a short chain of amino acids. They can be created synthetically, they can be isolated, and they are natural. The body doesn't care whether a peptide is "natural" or synthetic; what matters is its exact molecular structure.

• FDA-approved peptide drugs go through years of rigorous testing in animals and humans to prove both safety and effectiveness before reaching the market.

• Calling something "scientifically proven" can be misleading when the underlying evidence is weak, preliminary, or based only on rat studies. Especially as much of the "science" cited on peptide marketing sites comes from small, limited animal, or cell studies, not large, controlled human trials.

• Just because a product is available online or from a compounding pharmacy does not mean it is FDA-approved, well-studied, or safe; consumers must look beyond hype and ask what evidence truly exists.

• A naturally occurring peptide is generally not going to be suitable for use therapeutically.

"You can say that something is scientifically demonstrated because it showed something interesting in a rat. The key is that the people may not ask that, because a lot of times people hear 'scientific terminology' and it makes something sound really legitimate, but it doesn't mean that there's solid data." — Dr. Leigh Baxt

Evaluation of Research Grade Peptides Marketed Directly to Consumers Reveals Extensive Variability in Purity and Measured Abundance: https://www.preprints.org/manuscript/202604.1748

Connect with Dr. Leigh Baxt:

Professional Bio: https://www.mskcc.org/profile/leigh-baxt

LinkedIn: https://www.linkedin.com/in/leigh-baxt-314b877

Connect with Therese:

Website: www.criticallyspeaking.net

Bluesky: @CriticallySpeaking.bsky.social

Instagram: @criticallyspeakingpodcast

Email: theresemarkow@criticallyspeaking.net

Audio production by Turnkey Podcast Productions. You're the expert. Your podcast will prove it.