In Defense of Sunlight by Rowan Jacobsen: Rethinking Sun Exposure, Circadian Health, and Modern Wellness

For decades, sunlight has largely been framed through a single lens: something to limit, block, or avoid.

However, a growing body of research, and a new wave of science-driven storytelling, is asking us to reconsider that simplicity.

That conversation is brought into focus in In Defense of Sunlight: The Surprising Science of Sun Exposure by Rowan Jacobsen, a journalist known for translating complex environmental and biological systems into accessible narratives that challenge conventional wellness thinking.

Rather than treating sunlight as purely harmful or purely beneficial, Jacobsen explores something more nuanced:

What if our modern lifestyle has disrupted our relationship with light itself?

 

One of the central philosophies reflected in Jacobsen’s work is a systems-based approach to health.

Instead of isolating sunlight as a single variable (good vs. bad), he examines how it interacts with interconnected biological systems, including:

This creates a new ideology in wellness writing: moving away from reductionist thinking and toward understanding the body as an adaptive system shaped by environment.

In that context, sunlight goes beyond being UV exposure, it is information for the body.

A major thread in modern sunlight research—and one that Jacobsen highlights—is the role of light in regulating circadian rhythm.

Morning light exposure signals the brain to reduce melatonin, increase cortisol at appropriate levels, and activate alertness pathways that help regulate energy throughout the day.

This aligns with broader circadian biology research showing that:

In this framing, sunlight is not just something humans randomly encounter; it is something the body reads and responds to continuously.

Importantly, Jacobsen’s exploration does not reject established dermatological science.

The book exists within a long-standing scientific tension:

• Dermatology emphasizes the well-documented risks of UV exposure, including skin cancer and photoaging
• Emerging circadian and environmental health research emphasizes the risks of insufficient natural light exposure in modern indoor life

Both are true, and the most responsible reading of this science is not either/or, but both/and.

This is where nuance matters most in modern sun care conversations.

A key philosophical thread running through Jacobsen’s work is cultural, not just biological. Modern life has dramatically reduced our direct exposure to natural light.

Between indoor work, artificial lighting, screens, and climate-controlled environments, many people now experience sunlight in fragmented, limited ways which raises an important question:

Have we optimized for protection at the expense of connection?

Not to replace protection but to reconsider balance.

At Sun Love, this evolving conversation aligns with a simple belief:

Sun care is not avoidance, it is awareness, it is integration, it is self-care. 

It includes:

• Intentional morning light exposure
• Nutrient-rich, hydration-supporting foods
• Mineral SPF during prolonged UV exposure
• Physical protection (hats, shade, clothing)
• Skin hydration and barrier support before and after sun exposure

Because what needs to be understood across the board is that modern sun care has nothing to do with extremes, it’s about living in rhythm with the sun instead of reacting to it.

What makes In Defense of Sunlight feel culturally timely is not that it challenges everything we know, but that it mirrors a shift already happening in how we approach wellness.

We’re moving away from fear-based thinking and toward something more layered, where health is understood through systems, rhythms, and context.

Sunlight isn’t something to label as good or bad. It’s part of how we function; quietly shaping energy, mood, and daily rhythm. So the question becomes less about avoidance, and more about relationship.

How do we spend time in it? How do we care for ourselves within it?

That’s where ritual comes in. That’s where SUN LOVE lives. In the small, intentional practices that make time outside feel supported, balanced, and a little more beautiful so you don't have to sacrifice living your best life in the sunshine! 

Jacobsen didn't write a quiet little science book, he wrote one that's sparking actual arguments and discussions, between actual people who grew up afraid of their own backyard. 

At SUN LOVE, we love learning about peoples experiences and relationships with sunlight as wellness. Here's where the conversation is continuing:

1. The Joe Rogan Experience (#2516) The conversation goes deep into the biology of why sunlight feels good. Rogan and Jacobsen get into the paradox of how something that boosts vitamin D and mood got labeled inherently dangerous. The standout moment: Jacobsen explaining that sunlight literally triggers opiate release in the brain, which reframes "I just feel better outside" as actual neurochemistry, not vibes. → Listen on Spotify | Watch on YouTube

2. Slate (book excerpt) This is Jacobsen telling his own origin story; years of noticing how brutal Vermont winters affected him, which sent him down a seven-year research rabbit hole into sunlight. The science nugget worth lifting: a 2014 Harvard study found that sun-exposed skin cells produce cortisol, which sharpens focus and burns more energy; basically real evidence behind "sunny day = productive day." → Read the excerpt

3. EconTalk (Russ Roberts) The most historically minded conversation of the bunch. It traces the early-1900s "heliotherapy" movement that treated rickets and tuberculosis with sunlight, and questions whether older sunscreen formulations may have done more harm than good. Great source if you want a more skeptical, slow-burn angle for the blog rather than a hype clip. → Listen at EconTalk

4. Nature (book review) The most scientifically credentialed take. The reviewer calls Jacobsen a "light evangelist," and highlights a study of lifeguards whose skin, by the end of a sun-heavy summer, had developed beneficial microbes that help defend against UV damage. That lifeguard detail is a great visual hook if you want a "your skin builds its own sunscreen" angle. → Read the review

5. Matt and Shane's Secret Podcast (Ep 620) The comedy-podcast crossover, less science-dense, more "regular guy reacts to finding out everything he was told about sunscreen might be wrong." Good for reach into an audience that wouldn't otherwise pick up a science book. → Watch on YouTube