Podcast Summary: The Dr. Josh Axe Show
Episode: The SHOCKING Science of Daily Red Light and Sauna Use
Host: Dr. Josh Axe
Guest: Connie Zak, Co-founder of Sunlighten
Date: December 4, 2025
Main Theme & Purpose
This episode explores the science and practical applications of red light therapy and sauna use, focusing on their impact on mitochondrial health, aging, disease prevention, and personal wellness. Dr. Axe and guest Connie Zak delve into the cellular and physiological mechanisms behind infrared light and heat, discuss the latest biohacking technologies, and offer actionable advice for listeners seeking natural ways to enhance their health, energy, and longevity.
Key Discussion Points & Insights
1. Origins & Personal Motivations
[04:04–05:29]
- Connie entered the sauna space due to her brother’s battle with chronic illness, later identified as mercury toxicity. Infrared technology profoundly improved his health.
- Both Connie and her husband/business partner left corporate pharma jobs to bring infrared sauna technology to a wider audience, motivated by transformative personal experiences.
Quote:
"We left our corporate jobs at Procter and Gamble...There was no plan B...and we had to make it work."
— Connie Zak [05:01]
2. Infrared vs. Traditional Finnish Saunas
[06:30–09:39]
- Infrared saunas: Heat the body directly via specific wavelengths, leading to cellular and mitochondrial benefits.
- Traditional Finnish saunas: Heat the air to higher temperatures, leading mostly to surface-level heating.
- Infrared is described as “energy medicine,” while Finnish saunas are “heat medicine.” Patients with health issues (hypothyroidism, Lyme, chronic fatigue, mitochondrial dysfunction) tend to benefit more from infrared.
Quote:
"Infrared is more like energy medicine versus heat medicine because it's a wavelength of light...There’s four different parts that impact the body in completely different ways."
— Connie Zak [08:39]
3. Five Hallmarks of Aging and Infrared’s Impact
[11:13–15:10]
- Hallmarks affected by infrared:
- Mitochondrial dysfunction
- Cellular senescence ("zombie cells")
- Inflammation (primary aging cause)
- Gut dysbiosis
- Stem cell vitality
- Infrared therapies cleanse, repair cells and support stem cell function.
- The body’s biological age can differ dramatically from chronological age; infrared can help reverse organ aging.
Quote:
"Infrared helps to connect with the mitochondria and make it...more functional so that your body is healthier and can repair itself."
— Connie Zak [12:34]
4. Mitochondrial Health, Energy, and Cellular Cleaning
[15:10–18:43]
- Testing: Functionality of mitochondria can now be tested, validating energy improvements from infrared.
- Blood flow: Infrared increases circulation by up to threefold, enhancing oxygen and nutrient delivery for healing and mental clarity.
Quote:
"It is not a mild flow change. It is a significant flow change...up to three times more blood flowing in your body instantly."
— Connie Zak [00:30 & 18:44]
5. Brain Health, Exercise Mimicry, and Mental Clarity
[18:43–20:12]
- Enhanced blood flow via infrared is especially beneficial for the brain, improving cognition and reducing mind chatter.
- Described as an "exercise mimetic"—providing many benefits of exercise, increasing exercise tolerance.
- Mental health and brain resilience are key passions for Connie.
6. The Role of Sunlight, Deficiency, and Technology
[20:12–21:53]
- Infrared and red light fill a crucial gap created by modern indoor lifestyles lacking sunlight.
- Therapies like sauna act as “supplements of the sun” for vital energies historically gained through outdoor living.
Quote:
"We get just a fraction of the amount of sun we should be getting...I think that’s why people are responding so well to things like sauna, because there’s a major deficiency."
— Dr. Josh Axe [20:37]
7. Skincare, Collagen, and Infrared Red Light Masks
[21:53–29:16]
- Introduction of a new, unreleased red light/infrared mask for skin health, leveraging Sunlighten’s experience and research.
- The device uses both red and near-infrared wavelengths for maximal collagen, elastin, and cell turnover benefits (e.g., anti-aging, acne, skin glow).
- The mask is comfortable, cordless, easy to use; optimal session is 3–12 minutes.
Quote:
"Near infrared is...important to have the two together...near infrared penetrates deeper and it's important to have the two together."
— Connie Zak [24:03]
8. Cold Therapy: Personalized Approaches and Cautions
[31:10–37:46]
- Cold therapy’s benefits differ by sex and health conditions:
- Men often benefit more (HRV, sleep, heart rate).
- Women should moderate exposure, paying attention to cycle, temperature, and individual response. Extreme cold is not better.
- Overuse can be detrimental; optimal frequency is 1–3x/week for women, shorter durations (2–3 minutes), higher temperatures (59–60°F).
- For hypothyroid, immune-challenged, or cold-intolerant individuals, prioritize warming therapies (sauna/red light).
Quote:
"There is a huge difference between men and women when it comes to cold...Women need to pay attention to their cycle...Women should take it at higher temperatures."
— Connie Zak [35:30]
9. Contrast Therapy (Hot & Cold), Individualization
[37:46–38:38]
- Contrast therapy: Alternating between hot and cold can ‘pump’ nutrients for injury recovery (e.g., low back pain, sprains).
- Individual needs and body types determine the best therapies.
10. Stress, Cortisol & Parasympathetic Activation
[38:38–42:51]
- Infrared and red light therapies rapidly shift the body from "fight or flight" to a relaxed parasympathetic state.
- Notable biomarker improvements: increased HRV, reduced cortisol, improved sleep, and subjective energy boosts.
Quote:
"As soon as you get in [the sauna]...that energy immediately starts to relax your body...the cortisol comes down, the flow starts to happen."
— Connie Zak [39:08]
11. Health Metrics: Tracking Wellness
[41:12–42:51]
- HRV and sleep quality are valuable markers for tracking improvements.
- Early intervention when biometrics show decline is advised (e.g., addressing infection/illness at first sign).
12. Heart Health & Clinical Outcomes
[43:54–45:37]
- Infrared sauna therapy linked to significant reductions in blood pressure, improved quality of life, and detoxification in rigorous studies.
- Long-term benefits: For heart failure patients, five-year studies showed over 50% reduction in mortality and hospitalization.
Quote:
"Those who used infrared over five years had a 50% reduction in hospitalization and death."
— Connie Zak [45:37]
13. Practical Use & Habit Stacking
[45:37–49:47]
- Sauna guidelines: Start with 15–20 minutes, 3x/week, gradually increase as tolerated; consistency trumps duration.
- Habit stacking: Use sauna time for meditation, breathwork, intention setting for enhanced mental health benefits.
- Red light mask/panel designed for user-friendly, pre-programmed sessions; mask cycles through specific wavelengths/programs.
Notable Quotes & Memorable Moments
- "Infrared heats the body directly and is absorbed into the body...infrared is more like energy medicine versus heat medicine." — Connie Zak [08:39]
- "Infrared helps to connect with the mitochondria and make it...more functional so that your body is healthier and can repair itself." — Connie Zak [12:34]
- "It is not a mild flow change. It is a significant flow change...up to three times more blood flowing in your body instantly." — Connie Zak [18:44]
- "Infrared is a supplement that is to the sun...we’re getting just a fraction of sunlight that we should." — Dr. Josh Axe [20:37]
- "Women need to pay attention to their cycle...Women should take it at higher temperatures [for cold therapy]." — Connie Zak [35:30]
- "Consistency is key. Better to do 15 minutes more consistently than one session at 40. Consistency is key." — Connie Zak [47:11]
- "You can do habit stacking...meditate, breathwork, intention setting...combining those habits is so powerful for your brain." — Connie Zak [48:09]
Important Segment Timestamps
- Start of main discussion / Why infrared works: [00:30]
- Connie's entry into the space / Personal story: [04:04]
- Infrared vs. Finnish sauna: [08:23–10:51]
- The five hallmarks of aging: [11:13–15:10]
- Mitochondrial energy, blood flow: [16:40–18:44]
- Infrared as sunlight supplement: [20:12–21:53]
- Discussion of red light mask for skin health: [21:53–29:16]
- Cold therapy nuances: [31:10–37:46]
- Contrast therapy for injuries: [37:46–38:38]
- Reducing cortisol/stress via sauna: [38:38–42:51]
- Impact on heart health & studies: [43:54–45:37]
- Practical tips, usage protocol & habit stacking: [45:37–49:47]
In Summary
This episode offers an in-depth, practical, and inspiring look at how daily use of infrared saunas and red light therapy can dramatically improve health at the cellular level, enhance energy, slow (and even reverse) aging, and support the mind and body against modern stressors. The conversation highlights the importance of individualization with both heat and cold therapies, provides actionable strategies for integrating these tools into a routine, and underscores the power of consistency and habit-stacking in achieving lasting wellness. The episode is rich in both scientific explanation and motivational wisdom, making a persuasive case for the inclusion of red light and sauna therapies in a modern, natural health regimen.