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How to Enhance Your Immune System | Dr. Roger Seheult

Episode 217 Feb 24, 2025 3h 28m 19 insights
My guest is Dr. Roger Seheult, M.D., a board-certified physician in internal medicine, pulmonary diseases, critical care, and sleep medicine at Loma Linda University. We discuss the powerful benefits of light therapy, including infrared light, red light, and sunlight, for improving mitochondrial function in all the body’s organs. We also explore ways to reduce the risk of influenza, colds, and other illnesses that affect the lungs, sinuses, and gut. Topics include the flu shot, whether handwashing truly prevents illness transmission, and treatments for long COVID and mold toxicity. We review the efficacy of N-acetylcysteine (NAC), the power of hydrotherapy for combating infections, and strategies for improving sleep and overall health. Additionally, we discuss air quality. This episode provides actionable, science-based tools for preventing and treating infectious illnesses. Read the episode show notes at hubermanlab.com. Sponsors AG1: https://drinkag1.com/huberman Joovv: https://joovv.com/huberman Eight Sleep: https://eightsleep.com/huberman LMNT: https://drinklmnt.com/huberman Function: https://functionhealth.com/huberman Our Place: https://fromourplace.com/huberman Timestamps 00:00:00 Dr. Roger Seheult 00:02:16 Avoiding Sickness, Immune System, Tool: Pillars of Health, NEWSTART 00:08:03
Actionable Insights

1. Prioritize Daily Sunlight Exposure

Expose your skin to 15-20 minutes of natural sunlight daily, even on cloudy days, as infrared light penetrates deep into the body, stimulating mitochondria to produce melatonin and increase efficiency, which is crucial for overall health and combating age-related decline. If fair-skinned, wear a broad-rimmed hat and long-sleeved shirt to limit UV exposure while still benefiting from infrared light.

2. Ensure Dark Nights for Sleep

Maintain complete darkness in your sleeping environment, using blackout curtains or an eye mask, as even dim artificial light (e.g., 100 lux) at night can significantly suppress melatonin production and negatively impact morning blood glucose levels. If you need to navigate at night, use a flashlight pointed away from your eyes or a red light source.

3. Practice Mild-to-Moderate Exercise

Engage in mild to moderate exercise regularly, as this type of physical activity is shown to reduce inflammation in the body, contributing to a healthier immune system.

4. Adopt Natural, Unprocessed Nutrition

Focus on consuming foods that are as natural as possible and actively avoid processed foods to support overall health and immune function.

5. Prioritize 7-8 Hours of Sleep

Aim for 7-8 hours of quality sleep each night, as good sleep habits are directly linked to a much better immune system, improving antibody response and reducing the frequency of illness.

6. Cultivate Thankfulness & Forgiveness

Practice thankfulness and unconditional forgiveness, as these mental states are associated with less anxiety, fewer somatic complaints, and an overall greater sense of well-being, contributing to physical health.

7. Engage in Heat-Cold Contrast Therapy

Utilize hot baths, saunas, or hot fomentations (hot towels) to elevate your core body temperature to around 38-39°C (100.4-102.2°F), followed by a short cold exposure (e.g., a cold shower). Heat increases interferon secretion (a broad-spectrum antiviral), while cold causes vasoconstriction, liberating white blood cells into circulation and helping to ’lock in’ the heat.

8. Spend Time in Green Spaces

Seek out and spend time in natural green environments like forests or parks, as trees release phytoncides that stimulate the innate immune system and reduce stress, and green leaves reflect additional beneficial infrared light.

9. Maintain Adequate Hydration

Drink sufficient water to maintain proper sodium concentration in your body, as adequate hydration is essential for kidney function, toxin removal, and overall cellular health.

10. Avoid Toxins (Smoking, Vaping)

Refrain from inhaling anything other than clean air or prescribed medicines, specifically avoiding smoking and vaping, as these introduce irritants and toxins that are detrimental to lung health and overall well-being.

11. Consider NAC for Flu/Cold Symptoms

Take 600 milligrams of N-acetylcysteine (NAC) twice a day during winter or flu season for up to three months to replenish glutathione, act as a mucolytic, and significantly reduce the severity of influenza symptoms like runny nose and sore throat.

12. Consider Zinc Supplementation

Supplement with up to 40 milligrams of elemental zinc daily, as zinc acts as a cofactor for several immune system enzymes, potentially benefiting overall immune function. Monitor copper levels with long-term high-dose zinc use.

13. Use Eucalyptus Oil Externally for Congestion

If congested, use eucalyptus oil externally by rubbing a few drops on the skin or adding it to hot water for steam inhalation. Do not ingest eucalyptus oil internally, as it can be toxic.

14. Do Not Suppress Fever (Unless Advised)

Generally, avoid immediately suppressing a fever with medication, as fever is a natural immune response that helps the body fight infection by increasing the production of antiviral interferon.

15. Utilize Intermittent Fasting for Mitochondrial Health

For conditions like long COVID or general metabolic health, consider practicing intermittent fasting (e.g., avoiding food after 5:30 PM) to allow the body to generate new, healthy mitochondria by breaking down damaged cells and promoting regeneration.

16. Use Artificial Red/Near-Infrared Light

If natural sunlight exposure is consistently scarce (e.g., in winter in northern latitudes), consider supplementing with low-amplitude red/near-infrared lamps for 15-20 minutes a day to support mitochondrial function. Avoid excessive intensity, as more is not necessarily better.

17. Humidify Air in Cold/Dry Environments

If prone to respiratory issues in cold, dry environments, consider using a humidifier, especially at night, to prevent drying out of respiratory pathways.

18. Practice Smell Training

If experiencing a loss of smell or taste (e.g., post-COVID), engage in smell training using a variety of distinct odors (e.g., lemon, coffee, chocolate) to help reactivate and regenerate olfactory neurons.

19. Communicate Knowledgeably in Hospital

When a loved one is admitted to the hospital, ask intelligent, informed questions about their disease and treatment plan. This signals to the medical staff that you are engaged and knowledgeable, which can lead to more thorough and attentive care.