How Sunlight Can Fight Autoimmune Disease

When you think about sunlight, you probably picture warm summer days — not a cutting-edge medical treatment. But as recent research reveals, specific wavelengths of UV light can help calm runaway inflammation, a key driver behind autoimmune diseases.

In this conversation, John MacMahon, co-founder of Cytokind and veteran medical device entrepreneur, shares how a dermatology treatment for psoriasis led to groundbreaking results for MS, COVID, and other inflammatory conditions. We dive into the science behind phototherapy, how it’s used in clinical trials, and why your immune system might be craving more sun than you realize.

You’ll hear:

• Why a narrow band of UV light can “teach” your immune system to make better decisions
• How clinical trials in COVID and MS have shown dramatic reductions in mortality and relapses
• Why inflammation — not just symptoms — should be the focus of autoimmune care
• What you can do today to naturally boost your regulatory T cells (hint: it’s free)

If you or someone you love is living with an autoimmune condition, this episode could open the door to a whole new way of thinking about treatment and prevention.

Links & Resources

• Learn more on Cytokind’s website: cytokind.net
• Can Sunlight Cure Disease? – Scientific American (May 20, 2025) — Explores UV light therapy for autoimmune conditions like MS, including patient Kathy Reagan Young’s “UV-fueled rebirth” and underlying photoimmunology research.

NB-UVB lights are FDA-cleared for dermatology from pediatrics to geriatrics.
Their use beyond dermatology is experimental in the US.

Timestamps

0:00 - Intro
2:15 - Why sunlight matters for healthspan and immunity
4:10 - John’s journey into medical devices and phototherapy
6:55 - How UVB light “teaches” your immune system to regulate inflammation
9:22 - COVID-19 clinical trial results and survival rate impact
13:48 - The MS connection and Dr. Prue Hart’s groundbreaking study
18:36 - How the device works and what patients can expect
21:50 - Potential benefits for stress, sleep, and aging well
26:05 - Insurance coverage, FDA path, and future trials
31:42 - Simple steps you can take today to support immune health
34:40 - Closing thoughts and where to learn more

What’s Next?

Do you or someone you love live with an autoimmune condition? Are you curious about simple, safe ways to reduce inflammation and improve your healthspan?

If you have questions about this episode or ideas for future topics, reach out to us at [e-mail]

We’d love to hear from you.