Podcasts > Huberman Lab > Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo

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

By Scicomm Media

In this episode of the Huberman Lab, Dr. Melissa Ilardo discusses her research on genetic adaptations in human populations, focusing on the Bajo people of Indonesia and their extraordinary diving abilities. She explains how certain populations develop genetic variations that help them thrive in specific environments, from enhanced breath-holding capacity to larger spleens that store oxygen-rich blood cells.

The conversation explores how genes, behavior, and environmental factors interact to influence human traits and performance. Huberman and Ilardo examine the role of epigenetics in modifying gene expression across generations, the impact of genetic beliefs on physical performance, and the ethical considerations surrounding gene-editing technologies like CRISPR. They address questions about therapeutic interventions versus genetic enhancements, using real-world examples to illustrate these complex topics.

Listen to the original

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

This is a preview of the Shortform summary of the May 26, 2025 episode of the Huberman Lab

Sign up for Shortform to access the whole episode summary along with additional materials like counterarguments and context.

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

1-Page Summary

Genetic Variations and Adaptations in Specific Human Populations

Melissa Ilardo studies the Bajo people of Indonesia, traditional sea nomads with remarkable diving abilities who can hold their breath for extended periods and dive to depths of 200 feet. Her research reveals that the Bajo have developed genetic adaptations, including larger spleens that act like biological scuba tanks, storing more oxygen-rich red blood cells. This adaptation, linked to a gene variant affecting thyroid hormone levels, appears in both diving and non-diving Bajo individuals.

Ilardo explains that such adaptations emerge when existing genetic variations become advantageous in specific environments, leading to accelerated evolutionary changes. Andrew Huberman adds that genetic variations can influence cognitive and behavioral traits, citing examples like the correlation between autism and exceptional abilities in focused tasks.

Mechanisms Behind Exceptional Human Diving Abilities

The mammalian dive reflex plays a crucial role in human diving abilities, as Ilardo explains. This reflex optimizes oxygen availability and prioritizes blood flow to critical organs during breath-holding. She notes that sea nomads can hold their breath for up to 13 minutes while actively diving and spearfishing, and their physiological adaptations include slowed heart rates and constricted blood vessels in extremities.

Particularly interesting are the Hanyo women divers of Jeju Island, who dive in cold waters even during pregnancy. Ilardo's research suggests they possess genetic variations that protect them from adverse effects of breath-holding during pregnancy, including protection against hypertensive disorders.

Genes, Epigenetics, and Behavior in Human Traits and Evolution

Environmental factors can modify gene expression through epigenetics, with changes sometimes spanning generations. Huberman discusses mate choice, noting that humans prefer partners with different immune systems, potentially providing offspring with more diverse immune protection. Ilardo adds that beliefs about genetic predisposition can influence performance, as demonstrated by studies where participants performed better when told they had beneficial genetic traits.

Ethical Issues in Human Genetics and Gene Editing

The emergence of gene-editing technologies like CRISPR raises complex ethical questions. While these tools could prevent genetic diseases, Huberman and Ilardo discuss concerns about unintended consequences and potential misuse, citing the controversial case of a Chinese scientist who modified babies' genomes. They explore the challenging distinction between therapeutic interventions and enhancements, with Ilardo presenting thought-provoking scenarios about what constitutes a genetic "defect" versus normal human variation.

1-Page Summary

Additional Materials

Actionables

  • You can explore your genetic heritage to better understand potential health predispositions by using direct-to-consumer genetic testing kits. These kits can provide insights into traits that may be advantageous or require attention in your environment, similar to how the Bajo people's larger spleens are beneficial for diving. For example, if you discover a genetic predisposition for a strong immune system, you might focus on careers or hobbies that align with this trait, such as working in environments where exposure to pathogens is higher.
  • Enhance your cognitive and behavioral traits by engaging in activities that may be linked to your genetic variations, much like the correlation between autism and focused task abilities. If you find you have a knack for intense concentration, consider taking up hobbies like puzzle-solving, programming, or music, which can harness this ability and potentially lead to personal or professional development.
  • Educate yourself on the basics of epigenetics and start incorporating lifestyle changes that could positively influence your gene expression. This might include adopting a healthier diet, regular exercise, stress management techniques, and avoiding environmental toxins, drawing parallels to how environmental factors can modify gene expression in populations like the sea nomads. By making these changes, you could potentially impact not only your own health but also that of future generations.

Get access to the context and additional materials

So you can understand the full picture and form your own opinion.
Get access for free
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo

Genetic Variations and Adaptations in Specific Human Populations

Populations With Exceptional Underwater Diving Abilities

Bajo of Indonesia and Hanyo of Jeju Island Have Evolved Physiological Adaptations Like Larger Spleens to Thrive As Sea Nomads and Divers

Melissa Ilardo studies the Bajo people of Indonesia, traditional sea nomads known for their exceptional diving abilities. The Bajo can hold their breath for extended periods and dive to depths of around 200 feet, with skills reflected in their craftsmanship of jewelry using materials like black coral found at significant depths. These diving skills have a strong cultural value and potentially impact reproductive success within the Bajo population.

Ilardo has found that the Bajo have physiological adaptations, such as larger spleens, which function akin to biological scuba tanks by storing more oxygen-rich red blood cells. This genetic adaptation enables them to dive longer and safer. The presence of larger spleens in both divers and non-divers among the Bajo, compared to individuals from a nearby farming village, suggests a genetic basis for this trait. A gene variant in the Bajo population is associated with higher thyroid hormone levels, resulting in a larger spleen. The phosphodiesterase enzymes, which have evolved in the Bajo, have multiple functions and may impact several systems beyond diving. Ilardo suggests that with proper training, the Bajo could potentially excel in competitive freediving due to their biological advantages.

Rapid Spread of Genetic Variations in Isolated Populations due to Strong Selective Pressures

Ilardo explains that adaptations like those seen in the Bajo arise when "standing variation" (pre-existing genetic diversity) becomes advantageous in specific environments, leading to accelerated evolutionary changes. Dietary needs and pursuit of resources, such as protein and fats, have driven human evolution, sometimes in unexpected ways. She discusses how the adaptation for high-altitude survival in Tibetans likely originated from Denisovans, becoming advantageous as their ancestors moved to high altitudes. This beneficial genetic adaptation spread through the population over time.

Genetic Variations May Influence Cognitive, Behavioral, and Physical Traits

Andrew Huberman discusses the potential of genetic variations influencing cognitive and behavioral traits. For example, there appears to be a correlation between autism and exceptional ability in focused tasks, w ...

Here’s what you’ll find in our full summary

Registered users get access to the Full Podcast Summary and Additional Materials. It’s easy and free!
Start your free trial today

Genetic Variations and Adaptations in Specific Human Populations

Additional Materials

Actionables

  • Explore your genetic heritage to better understand potential predispositions by using direct-to-consumer genetic testing services. These tests can provide insights into traits that may influence your physical capabilities, dietary tolerances, or risk factors for certain conditions. For example, if you discover a genetic variant common in populations adapted to high altitudes, you might find that you have a natural advantage in endurance sports at elevation.
  • Incorporate a variety of focused tasks into your daily routine to potentially uncover hidden abilities. Given the correlation between conditions like autism and exceptional focus, you can experiment with activities that require intense concentration, such as puzzle-solving, programming, or learning a musical instrument, to see if you excel in areas that demand such skills.
  • Engage in a personalized diet and fitness plan that consid ...

Get access to the context and additional materials

So you can understand the full picture and form your own opinion.
Get access for free
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo

Mechanisms Behind Exceptional Human Diving Abilities

The ability of certain human populations to dive exceptionally well is largely attributed to physiological adaptations akin to the mammalian dive reflex, as well as potential genetic variations that protect divers from the impacts of this behavior.

Mammalian Dive Reflex Enables Prolonged Underwater Breath-Holding

Bajo and Hanyo: Larger Spleens and Dive Reflexes for Deeper, Longer Dives

Dr. Melissa Ilardo elaborates on the mammalian dive reflex, illustrating how the physiology of the spleen adjusts to cold water breath-holding, optimizing oxygen availability and red blood cell count. She links this ability to traditional sea nomads, like the Bajo, who have larger spleens believed to enhance this reflex for prolonged and deeper dives. These adaptations allow their body to prioritize oxygen to the critical organs like the brain and heart.

Ilardo also discusses how breath-holding can lead to a dangerous lack of oxygen since humans do not have a sensor for low oxygen levels, but rather an urge to breathe triggered by carbon dioxide buildup. She highlights this risk by mentioning free divers like Andrew Huberman, who explains that exceeding one's breath-hold limitation can result in a sudden and fatal blackout underwater.

Further, Ilardo notes that sea nomads claiming to hold their breath underwater for 13 minutes are able to do this while actively diving and spearfishing, unlike static breath-hold record breakers. She comments on the dive reflex aspects such as a slowed heart rate, constricted blood vessels in extremities, and contracting spleens enhancing oxygen-rich red blood cell circulation.

Physiological Adaptations Protect Against Diving Behavior Impacts

Genetic Variations May Shield Hanyo Women From Harmful Pregnancy Breath-Holding Effects

Ilardo points out the possibility of physiological and genetic adaptations in diving populations like the Bajo and Hanyo women divers of Jeju Island, who dive in cold waters without wetsuits, sometimes during pregnancy.

She suggests that the longstanding diving practice of the Bajo and Hanyo, along with large spleens, could imply a correlation with robust general health. This practice even extends into pregnancy for Hanyo women, who dive up until and shortly after giving birth, hinting at genetic variations that may shield the ...

Here’s what you’ll find in our full summary

Registered users get access to the Full Podcast Summary and Additional Materials. It’s easy and free!
Start your free trial today

Mechanisms Behind Exceptional Human Diving Abilities

Additional Materials

Actionables

  • You can practice controlled breath-holding in a safe environment, like a shallow pool with a buddy, to explore your body's natural dive reflex. Start with short intervals of holding your breath while floating, gradually increasing the duration as you become more comfortable and aware of your body's signals. This can help you understand your limits and the sensations associated with the dive reflex without risking oxygen deprivation.
  • Incorporate cold showers or baths into your routine to acclimate your body to cold water exposure, similar to the Hanyo women divers. Begin with lukewarm water and gradually decrease the temperature over time, focusing on controlled breathing and relaxation techniques. This could potentially improve your tolerance to cold and enhance your body's response to st ...

Get access to the context and additional materials

So you can understand the full picture and form your own opinion.
Get access for free
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo

Genes, Epigenetics, and Behavior in Human Traits and Evolution

Epigenetics: Behavior and Environment Modify Gene Expression and Heritability

Dr. Melissa Alardo and Andrew Huberman discuss the dynamic interaction between genes and environment, highlighting the role of epigenetics in human evolution and traits.

Trauma, Starvation, and Environmental Extremes Induce Inheritable Epigenetic Modifications

Melissa Ilardo notes that genes respond dynamically to environmental stimuli, sometimes with changes that span generations. She mentions how epigenetic changes, which involve modifications caused by molecules attaching to the genome, can be inherited. Instances such as refugee populations inheriting epigenetic changes related to trauma and historical famine-induced epigenetic modifications illustrate this phenomenon, despite no specific mentions in the provided transcript.

Mate Choice Impacts Genetic Makeup Over Time

Humans Prefer Mates With Different Immune Systems for Diverse Offspring

Andrew Huberman brings up the concept of hybrid vigor and the preference of both mice and humans for mates with a dissimilar major histocompatibility complex (MHC). This preference likely offers a genetic advantage by producing offspring with diverse immune systems. Melissa Ilardo references a study where individuals were more attracted to the scent of those with very different immune systems than their own. She and Huberman discuss how the globalization of human populations leads to unique genetic combinations that can impart both resilience and susceptibility to new diseases.

Genetic Variations Don't Strictly Dictate Traits; Environment and Mindset Notably Affect Abilities

Genetic Predisposition Beliefs Can Alter Performance

Huberman and Ilardo address the concept of genetic determinism, emphasiz ...

Here’s what you’ll find in our full summary

Registered users get access to the Full Podcast Summary and Additional Materials. It’s easy and free!
Start your free trial today

Genes, Epigenetics, and Behavior in Human Traits and Evolution

Additional Materials

Clarifications

  • Epigenetics involves changes in gene expression caused by external factors, not changes in the DNA sequence itself. These changes can be inherited and influence traits without altering the underlying genetic code. In human evolution, epigenetic modifications can be influenced by environmental factors like trauma or starvation, impacting how genes are expressed across generations. Understanding epigenetics helps explain how behaviors and environmental factors can shape genetic expression and contribute to the diversity of human traits.
  • Inheritable epigenetic modifications are changes in gene activity that can be passed down to offspring without altering the underlying DNA sequence. Trauma, starvation, and extreme environments can trigger these modifications, influencing how genes are expressed in response to specific environmental cues. This phenomenon highlights the dynamic interplay between an individual's experiences and their genetic inheritance, showcasing how environmental factors can leave lasting imprints on gene regulation across generations. Such modifications can potentially impact various aspects of an individual's traits and behaviors, demonstrating the complex relationship between genetics, environment, and evolution.
  • Hybrid vigor, also known as heterosis, is the phenomenon where offspring of genetically diverse parents exhibit enhanced traits compared to both parents. In the context of mate choice, preferring partners with different immune systems can lead to offspring with a more diverse set of immune genes, potentially resulting in stronger immune systems and better overall health. This preference for genetic diversity in immune systems is believed to offer an evolutionary advantage by increasing the chances of producing resilient and healthy offspring.
  • The major histocompatibility complex (MHC) is a set of genes responsible for immune system regulation. In mate choice, individuals are often attracted to partners with different MHC profiles, possibly due to an evolutionary advantage of producing offspring with diverse immune defenses. This preference may help offspring combat a wider range of pathogens, promoting genetic diversity and potentially healthier offspring. The MHC plays a role in odor perception, influencing attraction and mate selection based on immune system compatibility.
  • Globalization has led to increased human migration and intermingling of populations, resulting in diverse genetic combinations. These unique genetic mixes can confer both resilience and susceptibility to different diseases due to the varied immune responses they produce. The exposure to new pathogens and environmental factors in globalized societies can influence the evolution of human genetic diversity and impact disease outcomes. Understanding how genetic diversity shapes disease susceptibility is crucial for public health efforts in a globalized world.
  • Genetic determinism is the belief that an individual's trai ...

Counterarguments

  • While epigenetic modifications can be inheritable, the extent and permanence of these changes across generations are still under investigation, and not all epigenetic changes are necessarily passed down.
  • The relationship between trauma, starvation, and epigenetic changes is complex, and it is not fully understood how these changes might manifest in subsequent generations or how they might be reversed.
  • Mate choice for genetic diversity, while beneficial in some contexts, may not always result in positive outcomes due to potential cultural, social, or biological complications.
  • The concept of hybrid vigor, while observed in some cases, may not apply universally across all traits and populations, and there can be advantages to genetic similarity in certain contexts.
  • Globalization and the resulting genetic combinations can introduce complexities beyond just disease resilience, including the potential for increased prevalence of certain genetic disorders.
  • The influence of mindset and environment on abilities is significant, but it is also important to recognize that genetic factors do play a substantial role in many traits and should not be completely discounted.
  • The belief in genetic predispositions altering performance could be subject to placebo or nocebo effects, and such studies need to be interpreted with caution to avoid overestimating t ...

Get access to the context and additional materials

So you can understand the full picture and form your own opinion.
Get access for free
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo

Ethical Issues in Human Genetics and Gene Editing

As the potential of gene editing unfolds, Huberman and Dr. Alardo dive into the ethical questions raised by technologies such as CRISPR, which allows for human genome modification.

Gene Editing Tech Like Crispr Raises Ethical Questions About Human Genome Modification

The conversation addresses the promise and peril of gene editing in humans, where the ability to prevent certain genetic diseases comes packaged with substantial caution regarding unintended consequences, misuse, or societal discrimination.

Gene Editing May Prevent Genetic Diseases, but Concerns Include Unintended Consequences, Misuse, or Discrimination

Huberman and Dr. Alardo consider the possibilities offered by gene editing technologies like CRISPR. While these technologies have potential to eradicate genetic disease, there is trepidation surrounding their misuse and the unforeseen outcomes of altering the human genome. An incident is cited where a scientist in China was imprisoned after using CRISPR to genetically modify the genomes of babies, purportedly to make them resistant to HIV but also potentially affecting human memory. Such actions have incited worldwide condemnation from a community of genetic ethicists and scientists. Huberman suggests that parents with harmful mutations could desire to use CRISPR to prevent transmitting conditions like Huntington's disease to their offspring, underscoring the ethical complexities likely to feature prominently in future discussions.

Therapeutic vs. Enhancement Genetic Modifications Debate

The debate differentiates between "therapeutic" interventions aimed at treating recognized diseases and "enhancement" modifications that could lead to socioeconomical disparities or philosophical concerns.

Genetic Variations: Defects or Normal? a Philosophical and Ethical Debate

Ilardo highlights the challenging discussion of setting boundaries in gene editing between corrective measures and ...

Here’s what you’ll find in our full summary

Registered users get access to the Full Podcast Summary and Additional Materials. It’s easy and free!
Start your free trial today

Ethical Issues in Human Genetics and Gene Editing

Additional Materials

Counterarguments

  • The potential benefits of gene editing, such as eradicating genetic diseases, may outweigh the risks if proper regulations and oversight are established.
  • The concept of "normal human variation" is dynamic and may evolve with societal norms and scientific understanding, potentially redefining what is considered a "defect."
  • The distinction between therapeutic and enhancement interventions could be seen as arbitrary, as enhancements could also lead to improved quality of life and reduced healthcare costs in the long term.
  • The risk of misuse and unintended consequences exists in many areas of science and technology, and should not necessarily preclude the development and application of gene editing.
  • The concern about social discrimination due to cost barriers might be mitigated through policy measures, such as subsidies or public healthcare coverage for genetic testing and editing.
  • The argument that gene editing could lead to socioeconomic disparities assumes that access to the technology will remain unequal, which could change with advancements in affordability and accessibility.
  • The condemnation of the scientist in China may not reflect a consensus on the ethical use of gene editing but rather a reaction to the lack of transparency and regulatory compliance in that particular case.
  • The subjective nature of defining ...

Actionables

  • You can start a personal ethics journal to explore your views on genetic modification by writing down your thoughts on each ethical question raised by gene editing, such as the distinction between therapeutic and enhancement modifications. This reflective practice helps you clarify your own stance on complex issues and can guide your decisions if you ever face related choices in healthcare or family planning.
  • Engage in conversations with friends or family about the ethical implications of gene editing to develop a well-rounded perspective. Discuss scenarios like the potential to prevent genetic diseases versus the risk of social discrimination, and consider how you would feel if faced with these choices. This dialogue can help you understand the diverse opinions and emotional responses people have towards genetic technologies.
  • Create a hypothetical budget for a family con ...

Get access to the context and additional materials

So you can understand the full picture and form your own opinion.
Get access for free

Create Summaries for anything on the web

Download the Shortform Chrome extension for your browser

Shortform Extension CTA