What if improving your sleep, mood, energy and metabolic health began not with another supplement, but with changing the light around you?
In this episode of The Revital Health Podcast, Jodi Duval is joined by Daniel White and Jai Kapoor, co-founders of In Rhythm, to explore the emerging science of chronobiology and the profound relationship between light, our environment and human health.
Daniel is a Registered Nutritionist, Functional Medicine Certified Health Coach and Applied Quantum Biology Certified Health Practitioner, with extensive research and clinical experience in sleep science, circadian biology and human behaviour change.
Jai brings a very different but complementary perspective from his career as a senior executive within the artificial intelligence and technology sectors. He has helped build and scale several high-growth technology companies from their early stages, including Wayve AI and Revolut.
Daniel and Jai both arrived at this work through deeply personal health experiences.
Daniel describes experiencing significant circadian disruption during adolescence after years of late-night screen use, technology addiction, poor sleep, weight gain, anxiety and declining mental health. His search for answers led him into nutrition, psychology, functional medicine, circadian biology and photobiology.
Jai’s demanding career in artificial intelligence, finance and technology involved long working hours, chronic pressure and a highly stimulating lifestyle. After suddenly developing severe psoriasis, he explored a range of conventional and holistic approaches with limited success. It was only after changing his relationship with natural and artificial light that he began to experience significant improvements in his skin, sleep and wider health.
This experience became the catalyst for his work with Daniel and the creation of In Rhythm.
Together, Jodi, Daniel and Jai explore why light is one of the body’s most important environmental time signals and why modern life can create such a significant mismatch between our biology and our surroundings.
In this conversation, they discuss:
• Why circadian health involves much more than sleep
• How light helps regulate the body’s internal clocks
• Why bright, blue-enriched artificial light can keep the body in a perpetual “midday” state
• The potential effects of invisible light flicker on the brain and nervous system
• Why infrared light is an important component of natural light
• How indoor lighting may affect sleep, mood, energy and cellular repair
• Why children can be particularly sensitive to evening light
• The relationship between screen exposure, melatonin, sleep and behaviour
• Practical ways to improve a child’s evening light environment
• Morning light, UVA, UVB and gradually developing tolerance to sunlight
• Skin health, psoriasis and the timing of light exposure
• Why sunlight should be approached with respect rather than fear
• How eating earlier can support circadian and metabolic alignment
• Habit stacking light exposure, outdoor meals, movement and grounding
• In Rhythm’s LIGHTER framework for circadian health
• The Better Sleep Bulb and the limitations of conventional indoor LEDs
• The future of biologically coherent homes, schools, workplaces and healthcare environments
The LIGHTER framework includes:
L — Light first thing in the morning
Get outside as early as practical and allow natural morning light to reach the eyes and skin.
I — Include UVA
Gradually include appropriate natural light exposure as UVA becomes available during the day.
G — Gather UVB
When appropriate for your skin type, location and UV conditions, obtain measured UVB exposure without allowing the skin to burn.
H — Harness evening light
Use the natural light at the end of the day to help communicate to the body that daytime is finishing.
T — Turn off artificial light at night
Reduce bright overhead lighting, blue-enriched lighting and unfiltered screens during the evening.
E — Earth or ground
Spend time barefoot on natural surfaces or in natural water where safe and practical.
R — Regular early meal timings
Maintain consistent meal timing and aim to finish the final meal several hours before sleep.
This conversation offers a powerful reminder that health does not always need to be forced. When the appropriate environmental conditions are restored, the body may be better able to regulate, repair and return to rhythm.
This podcast is provided for educational purposes and does not replace individual medical advice. Sun and ultraviolet exposure should be approached carefully according to skin type, geographical location, UV index, medications, medical history and individual skin cancer risk. Avoid sunburn and seek personalised guidance where appropriate.
