Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo

Overview

This episode explores the fascinating interplay between genetics, behavior, and human performance. Dr. Melissa Ilardo shares groundbreaking insights into how behaviors like breath-hold diving can influence gene expression and organ function, such as spleen size, to improve oxygen availability. The discussion also delves into mate selection, immune system compatibility, and the ethics of gene editing, offering a nuanced look at how nature and nurture shape human health, resilience, and evolution.

Notable Quotes

- Most mutations are deleterious. It takes forever to create an advantage, but very little time to devolve a trait. – Dr. Melissa Ilardo, on the challenges of beneficial genetic mutations.

- The mate you would select is the one whose immune system composition is most different from yours, and you know that based on their smell. – Andrew Huberman, on the science of mate attraction.

- The spleen is like a biological scuba tank, giving you a 10% oxygen boost during a dive. – Dr. Melissa Ilardo, on the mammalian dive reflex.

🧬 Nature vs. Nurture in Gene Expression

- Dr. Ilardo explains how behaviors and environmental factors can modify gene expression through epigenetics, challenging the idea that DNA is entirely fixed.

- Trauma and famine have been shown to leave epigenetic marks that can be passed down generations, sometimes enhancing resilience but also creating vulnerabilities in different contexts.

- Eye color serves as a fascinating example of genetic inheritance, with all blue-eyed individuals tracing back to a single ancestor.

🌊 The Mammalian Dive Reflex & Human Adaptation

- The Bajau people, known as sea nomads, have evolved larger spleens, which contract during dives to release oxygen-rich red blood cells, enhancing their ability to hold their breath underwater.

- This adaptation is both genetic and behavioral, with non-divers in the Bajau population also exhibiting larger spleens.

- The dive reflex, triggered by cold water on the face, slows heart rate and redirects oxygen to vital organs, offering a 10% oxygen boost.

👃 Mate Selection & Immune System Compatibility

- Humans, like mice, are drawn to mates with immune systems most different from their own, often determined subconsciously through smell.

- This hybrid vigor enhances offspring's immune diversity, increasing resilience to pathogens.

- Globalization and intermarriage are creating unprecedented genetic combinations, potentially leading to new adaptations and vulnerabilities.

🏊‍♀️ Female Free Divers & Cardiovascular Health

- The Haenyeo, a group of Korean female divers, dive into cold waters well into their 70s and 80s, showcasing remarkable cardiovascular and physical resilience.

- Their heart rates drop dramatically during dives, a training adaptation that conserves oxygen.

- Genetic adaptations in this population may protect against pregnancy-related complications like preeclampsia, offering insights into potential medical therapies.

🧪 Ethics of Gene Editing

- The episode discusses the controversial use of CRISPR for genetic modifications, such as preventing diseases like Huntington’s or enhancing traits.

- Ethical dilemmas arise around defining defects versus enhancements and the potential for unequal access to such technologies.

- Dr. Ilardo emphasizes the need for caution, as CRISPR technology is still imprecise and carries risks of unintended genetic changes.