In this episode, our guest is Christina Friis Blach, co-founder of Lys Technologies, about how light shapes our health, performance, and daily lives.

They explore how sunlight exposure and circadian rhythms influence sleep, hormones, and energy—and why modern indoor environments often disrupt this balance.

Christina shares how her company is helping bridge the gap between science and real life through wearable light technology and sunlight analysis tools.

☀️ About Lys Technologies

Lys Technologies develops wearable sensors that measure the light you’re actually exposed to throughout the day—close to the eye, where it matters biologically.

Unlike traditional light meters used in architecture, their technology focuses on human-centric lighting, tracking how light impacts:

• Circadian rhythms and sleep
• Hormone regulation (melatonin, cortisol)
• Daily energy and performance

Their tools are used globally across research, healthcare, workplace design, and even elite sports—helping drive better sunlight analysis, building design, and behavior change.

☀️ Key Takeaways

• Light is a biological signal, not just for vision
• Modern lighting can disrupt circadian rhythms
• Wearable sensors enable real-world solar exposure tracking
• Natural light is critical in real estate and building design
• Shadow mapping and sunlight analysis are shaping healthier spaces

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.

In this thought-provoking episode, we sit down with Jonathan Jarecki, a 20-year-old pre-med student exploring the frontier of light biology, mitochondrial function, and the hidden impact of our modern indoor lifestyle.

What begins as a conversation about holistic health quickly evolves into a powerful exploration of how sunlight exposure, artificial lighting, and our disconnection from nature may be influencing everything from energy levels and brain function to chronic disease and mental health.

Jonathan shares his personal journey, from being raised in a household focused on lifestyle-based healing to diving into the scientific literature to understand why these approaches work. Along the way, he uncovers a missing piece in modern health conversations:

👉 Light is not just important—it may be foundational.

🌞 Sunlight vs Modern Living

We live in a world where:

• Most of our time is spent indoors
• Artificial LED lighting dominates our environment
• Morning sunlight exposure is rare
• Screen time is constant

Yet human biology evolved under full-spectrum natural sunlight.

This episode explores how that mismatch may be contributing to:

• Rising chronic disease
• Hormonal disruption
• Poor sleep and circadian misalignment

⚡ The Mitochondria Connection: Are We Light-Powered?

One of the most fascinating parts of the conversation dives into the science of mitochondria—the energy engines of our cells.

Jonathan breaks down complex biology into simple ideas, explaining how:

• Mitochondria convert food into usable energy (ATP)
• Light—especially red and infrared wavelengths—interacts directly with these systems

This raises a profound idea:

👉 Humans may not just run on food—we may also be deeply influenced by light as an energy source.

🧠 Light, Brain Function & Attention

The conversation also explores how light shapes:

• Brain chemistry
• Cognitive performance
• Mood and perception

From morning sunlight exposure to outdoor environments, we discuss how something as simple as getting outside early in the day can:

• Improve focus and clarity
• Regulate dopamine
• Reduce dependence on screens
• Support long-term mental health

In contrast, modern habits, like waking up and immediately scrolling, may be working against our biology.

🔬 Questioning Modern Science & Medicine

This episode doesn’t just explore light—it challenges how we think about health itself.

Jonathan highlights:

• The limitations of reductionist science
• The ongoing replication crisis in research
• The need for open-minded, systems-based thinking

Rather than viewing the body as separate parts (brain, gut, heart), we explore a more integrated model:

👉 The body as an interconnected energy system, influenced by light, environment, and lifestyle.

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.

In this special in-person episode of Sunlight Matters, recorded on a sun-drenched rooftop terrace in Alicante, Dave and Georg are joined by daylight expert Paul Rogers to explore the profound relationship between sunlight, architecture, and human wellbeing.

From the emotional impact of dark living spaces to the life-changing benefits of solar exposure, the conversation blends personal stories with expert insight. The trio reflects on how sunlight shapes our mood, energy, and health—often subconsciously—and why access to natural light should be a fundamental priority in housing design.

They also dive into the science and strategy behind sunlight analysis, shadow mapping, and solar exposure, highlighting how tools and awareness can transform the way we design homes, cities, and living environments. The discussion reveals a powerful truth: whether it's a terrace in Spain or a skylight at home, access to sunlight is not a luxury—it’s essential.

🔑 Key Topics Covered

• ☀️ Why humans instinctively seek sunlight
  From winter escapes to beach culture, we explore the biological and psychological drivers behind our attraction to the sun.
• 🧠 Sunlight and mental health
  Personal stories of living in dark basements and poorly lit homes reveal the deep connection between light deprivation and well-being.
• 🏡 The importance of daylight in architecture
  How window placement, skylights, and room proportions influence mood, productivity, and comfort.
• 🌇 Sunlight vs. shade: designing for different climates
  Why northern regions crave sunlight, while southern climates require intelligent shading strategies.
• 🧰 Shadow mapping & sunlight analysis
  How digital tools are revolutionizing real estate decisions, urban planning, and building design.
• 🌍 Light inequality and housing challenges
  A discussion on access to daylight as a social issue—and why better standards are needed.
• 🌞 The terrace effect
  Why even a small outdoor space with good solar exposure can dramatically improve quality of life.

💡 Key Takeaways

• Access to natural light is a core human need, not a luxury.
• Poor daylight design can negatively impact mental health and wellbeing.
• Sunlight analysis and shadow mapping are powerful tools for better homes and cities.
• Outdoor spaces with good solar exposure—like terraces—can transform daily life.
• Awareness is the first step: once people understand light, they begin to demand better environments.

🎧 Closing Thought

We don’t just enjoy sunlight—we depend on it. And whether through thoughtful design, better tools, or simply paying attention, reconnecting with the sun may be one of the most powerful ways to improve how we live.

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.

From Fight Camp to Sunlight:

In this episode of Sunlight Matters, guest host George Alexander speaks with professional kickboxer and osteopath Nathan, currently ranked #1 heavyweight in the UK for Muay Thai and #2 for K-1 kickboxing.

Nathan shares how working with previous podcast guest, health practitioner Teresa Bug, completely reshaped his approach to performance — moving beyond traditional calories-in/calories-out fitness culture into a deeper understanding of sunlight exposure, circadian rhythms, natural nutrition, and recovery.

The conversation explores how simple changes like morning sunlight exposure, red light therapy, better sleep timing, and natural food sources dramatically improved his energy, recovery, and training performance.

One of the biggest shifts Nathan made was understanding the importance of sunlight exposure and circadian health.

Key sunlight habits he implemented:

• Morning sunrise exposure whenever possible
• Using a near-infrared red light therapy panel during winter
• Planning his home orientation using a shadow mapping app to ensure morning sun

This is a practical example of sunlight analysis in real life, where sunlight exposure influences decisions such as choosing a flat with a balcony facing the sunrise.

• Sunlight exposure plays a major role in energy, sleep, and recovery.
• Red light therapy can help when natural sunlight isn’t available.
• Circadian health influences performance as much as training does.
• Natural food sources can replace many synthetic supplements.
• Small lifestyle changes can produce measurable performance improvements.

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.

Was the global ban on incandescent light bulbs really a climate breakthrough — or did we rush into a lighting revolution without fully understanding the biological and environmental consequences?

In this episode, Dave speaks with journalist and author Anna about her book Incandescent and her unexpected journey into the politics and science of modern lighting. What began as a personal health reaction to new “energy-efficient” bulbs became a much deeper investigation into how we regulate light, how we measure it, and how profoundly it shapes human life.

🌞 In This Episode:

• How Anna’s personal experience with CFL lighting sparked a global investigation
• Why incandescent bulbs were labeled “inefficient” — and what that metric ignored
• The limits of measuring light purely in lumens per watt
• How lighting regulations treated bulbs like simple appliances rather than biological influences
• The rise of LED lighting and the explosion of artificial light at night
• The impact of light on circadian rhythms, mood, immunity, and overall health
• The politics and ideology behind the global incandescent phase-out
• Why light pollution is an environmental issue hiding in plain sight
• Whether behavior change (dimming, switching off, reducing overlighting) matters more than bulb type

They explore how lighting policy focused almost entirely on efficiency while overlooking spectrum quality, flicker, environmental impact, and the complex ways light interacts with human biology.

From circadian rhythms and sleep health to the loss of dark skies and its effects on wildlife, this conversation asks a bigger question:

If every living system on Earth evolved under natural cycles of sunlight and darkness, what happens when we radically alter that balance?

Lightspiracy isn’t about nostalgia — it’s about rethinking our relationship with light, energy, and the rhythms that shaped us ☀️

📚 Further Reading

If this episode sparked your curiosity, explore Anna Levin’s powerful books on light, darkness, and our evolving relationship with illumination:

🌞 Incandescent: We Need to Talk About Light
A deeply personal and investigative journey into the global phase-out of incandescent lighting — and what it means for health, environment, and policy.
👉 https://saraband.net/sb-title/incandescent/

🌌 Dark Skies: A Journey into the Night
An exploration of light pollution, the loss of the night sky, and why darkness is essential for both human and ecological wellbeing.
👉 https://saraband.net/sb-title/dark-skies/

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.

What if the human body isn’t powered by calories alone?

In this thought-provoking episode, we sit down with Austrian filmmaker P.A. Straubinger, creator of the groundbreaking documentary In the Beginning There Was Light, to explore one of the most controversial and fascinating questions in modern science:

👉 What is life energy?

We dive into breatharianism, fasting, biophotons, mitochondria, the fourth phase of water, and the growing tension between scientific materialism and emerging research on light and consciousness.

Is the body just a biochemical machine — or is there more going on?

P.A. shares insights from over 10 years of research, interviews with scientists and spiritual practitioners, and the personal experiences that shifted his worldview beyond conventional biology.

We discuss:

• The limits of the caloric theory of metabolism
• Why up to 23% of human energy may be unexplained
• Fasting, autophagy, and Nobel Prize-winning science
• Light as an information carrier in food
• Gerald Pollack’s research on structured water
• Why questioning scientific dogma isn’t anti-science
• The importance of sunlight in modern living

This episode isn’t about proving breatharianism — it’s about opening a conversation around consciousness, light, metabolism, and our relationship to the sun.

If you're interested in bioenergetics, fasting, natural light, mitochondrial health, or the future of science, this conversation will challenge your assumptions in the best possible way.

🎬 Watch P.A.’s documentary: In the Beginning There Was Light

https://www.lightdocumentary.com/

Direct links to watch the movie on demand:

https://vimeo.com/ondemand/lightdocumentary (English subtitles)

https://vimeo.com/ondemand/lightus (English Voice Over)

And with a subscription on GAIA https://www.gaia.com/video/beginning-there-was-light

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.

Glass, Sunlight & Human Health

In the first episode of Series 2, we’re joined by daylighting expert and chemical engineer Joe Menchefski to explore a critical but often overlooked topic in modern building design: glass.

While low-E glass and LED lighting have dramatically improved energy efficiency, emerging research suggests they may also filter out parts of the light spectrum essential for human health.

Are our buildings optimized for energy — but not for biology?

🌞 What We Cover

• Why humans now spend 90–95% of their time indoors
• How low-E glass works — and what it blocks
• The possible link between filtered light and rising childhood myopia
• Why full-spectrum sunlight matters for eye development
• The impact of LED lighting on circadian rhythms
• Blue light, red light, and mitochondrial health
• The balance between energy efficiency and human wellbeing
• Vacuum-insulated glass (VIG) as a potential breakthrough
• Passive design, orientation, and smarter daylight strategies
• Why architects are beginning to rethink glass design

🔬 Key Themes

• Full-spectrum natural light is not just visual — it’s biological
• Buildings without proper daylight may impact sleep, metabolism, and productivity
• Energy efficiency alone is not a complete design strategy
• Health-optimized building design is an emerging frontier

🏗 Why It Matters

From rising myopia rates in children to circadian disruption in adults, the way we design windows, façades, and lighting systems may be shaping long-term public health outcomes.

This episode kicks off Series 2 by asking an essential question:

Are we designing buildings for performance metrics — or for people?

Read the accompanying blog here: https://shadowmap.org/learn/are-our-windows-making-us-sick

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.

In this insightful podcast discussion, friend of the podcast, Professor Glen Jeffery, sheds light on his recent study published in Nature (https://www.nature.com/articles/s41598-026-35389-6)

Introduction
In a world dominated by LED lighting, we often overlook its potential health consequences. Professor Glen Jeffery's groundbreaking study highlights the significant effects of artificial lighting on our vision and overall metabolic health.

The Research Background
Professor Jeffery begins by addressing growing concerns about how artificial lighting affects our health, particularly in environments with scarce natural light. The study was conducted in a building at University College London. The hypothesis was that the lack of natural light and the prevalence of LED lighting could be detrimental to overall health, particularly in terms of colour perception and metabolic functions.

The Experiment
The unique aspect of this study was its real-world setting. Instead of a controlled laboratory, the researchers chose an office environment where participants would typically work. Participants were given old incandescent light bulbs, which emit a broader spectrum of light, including infrared, crucial for metabolic health.

Surprising Results
The results were striking: participants showed a highly significant improvement in their vision after only a short exposure to incandescent lighting. This improvement persisted for months after the bulbs were removed, suggesting that exposure to a broader spectrum of light is vital for visual and metabolic health. Professor Jeffery emphasised that this study is a wake-up call about the damaging effects of LED lights, which may suppress our physiological functions, including colour vision.

The Importance of a Balanced Light Spectrum
Professor Jeffery highlighted that while LED lighting is often considered energy-efficient, it poses risks to human health by limiting the spectrum of light we are exposed to. He discussed the need for architects and lighting engineers to rethink building design, emphasising the importance of incorporating a wider spectrum of light for optimal health. The study also raised concerns about the glass materials used in buildings, which block essential infrared light.

Moving Forward: Practical Solutions
To address these challenges, Professor Jeffery suggests we don’t need to eliminate LEDs entirely. Instead, he advocates a balanced approach to lighting by integrating incandescent bulbs into our environments. Simple measures, such as using incandescent bulbs with dimmer switches, can mitigate the negative effects of LED lighting. He also urges policymakers to rethink regulations surrounding incandescent bulbs to ensure a healthier future.

Key Takeaways

1. LED lighting may impair our vision and metabolic health.
2. Exposure to incandescent bulbs can significantly improve colour perception and overall well-being.
3. A balanced approach to lighting, incorporating a variety of light sources, is essential for our health.
4. Policymakers must prioritise health implications when designing lighting regulations.

The paper is available for download here: https://www.nature.com/articles/s41598-026-35389-6

Sunlight Matters is a podcast exploring the role of the Sun in human health, architecture, cities, and everyday life.

Through conversations with scientists, architects, and technologists, the series examines how natural light shapes our bodies, our buildings, and the way we live indoors.

Hosted by Dave Wallace, Sunlight Matters asks a simple but overlooked question: what happens when we disconnect from the Sun?

Because sunlight isn’t optional. It matters.

Please do not forget to Like and Subscribe.