A groundbreaking new study published July 8, 2025 reveals that near‑infrared (NIR) light, specifically 850  nm, can penetrate the human torso (even through clothing) and significantly improve vision 24 hours after just a single 15‑minute LED exposure, even when the eyes are shielded from direct light.

In this follow-up conversation, Dr. Wunsch explores how early human exposure to forest-filtered light, our loss of visible body hair, and the development of erythema as a biological alarm system all influence how we interact with solar radiation today. The discussion extends from evolutionary adaptations to modern-day strategies for UV defense, including insights on the solar callus, the limits of artificial shade, and  how technologies like BlueSync represent a new frontier in light modulation. 

A new report from the MAHA initiative, chaired by Robert F. Kennedy, Jr., now serving as Secretary of Health and Human Services, highlights something simple but powerful: the light around us shapes the way we sleep, feel, and function. And for many of us, especially our kids, that light isn’t working in our favor.

Last week’s International Sunglasses Day serves as a timely reminder to consider the medical relevance of sunglasses. Used correctly, they provide important protection for the eyes—but if overused, they may impair chronobiological light perception and hormonal regulation.

Light is one of the most important, yet misunderstood, drivers of your health.

To explore these intricacies, we sat down with Dr. Alexander Wunsch, MD, PhD—a leading authority in photobiology and light medicine. A German physician, researcher, and author, Dr. Wunsch has spent decades investigating how light interacts with human biology and serves as the Chief Science Officer at Ra Optics. Our conversation took place in honor of the International Day of Light, diving into the complexities of photobiomodulation, skin phototypes, vitamin D levels, and the often misunderstood relationship between sun exposure and health.

Starting today, eligible U.S. customers can now purchase Ra Optics using their Health Savings Account (HSA) or Flexible Spending Account (FSA)—making our scientifically engineered eyewear even more accessible.

This means you can now protect your eyes, sleep, hormones, and energy with pre-tax dollars—a savings of 30–40%, depending on your tax bracket.

BlueSync is the result of a multi-year collaboration with Dr. Alexander Wunsch, one of the world’s foremost authorities in photobiology. During extensive discussions about the future of light-based technologies, Dr. Wunsch proposed a concept he had been quietly cultivating: a lens that does not merely block blue light indiscriminately, but rather selectively filters the spectrum in a manner that supports the human circadian system. This idea matured into what is now BlueSync, a revolutionary lens that represents a new category of eyewear: circadian-strengthening eyewear.

Sunlight: Between Cure and Caution by Dr. Alexander Wunsch, M.D., Ph.D.

Many biohackers treat sunlight as a cure-all. But like any medicine, it’s the dose, timing, and context that make the difference.

Introducing BlueSync, a novel protective eyewear technology designed to filter harmful short-wave radiation (UV and HEVL) from the sun, while preserving the beneficial elements. 

Developed in collaboration with the world’s leading expert in photobiology, BlueSync is the first lens scientifically designed to strengthen the circadian rhythm during the day.

Today is a special day in the Northern Hemisphere: The Winter Solstice. This annual milestone brings with it a unique blend of astronomical wonder and cultural significance. The Winter Solstice also brings significant changes to biological life on Earth. For example:

• Animals adapt by migrating, hibernating, or altering their behavior and physiology. Think of a bear hibernating in a cave.
• Plants enter a period of dormancy, responding to the light and temperature changes. Many plants lose their leaves and their energy descends into the roots, rather than the branches.

Now, how does the Solstice impact cultural life on Earth?

Welcome to Ra Optics, where science meets style in the world of eyewear.

The result?

A fusion of function and fashion.

In a recent study (the largest ever) on the impact of artificial light exposure on mental health, scientists found the most comprehensive evidence to date on the damaging effects of artificial (especially blue) at various times of the day.

Clearly…Ra Optics’ mission has never been more relevant.

Here is what you need to know about the latest Science of Light: