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.