What Is Human Centric Lighting? A Quick Guide to HCL

Posted March 3, 2026 by Natalie

A couple walking through a woods, with the suns rays breaking through the trees

We spend around 90% of our time indoors yet our bodies are still wired for natural daylight. A lack of sunlight and its visual – as well as non-visual – benefits can be a nightmare for our health. So what can we do? Step forward Human Centric Lighting (HCL). We’re receiving growing interest in this emerging concept, so here's a simple overview to explain how HCL works, where it's used and why it matters.

Human Centric Lighting: A Definition

Electric lighting was originally designed for indoor spaces, not for the people who use them. By contrast, Human Centric Lighting:

Is human-focused
Blends dynamic electric light with natural daylight
Supports mood, sleep, energy & productivity

Contemporary kitchen light colour & intensity matched to the time of day.

HCL (also known as circadian, wellness or biodynamic lighting) is not a product – it’s a combination of insightful design and smart technology. Although it can’t replace daylight, increasing research shows that it can replicate some of its positive effects. Hooray!

How Does Human Centric Lighting Work?

Daylight is the most important factor in regulating our circadian rhythm. This internal 24-hour biological clock influences physiological processes such as the healthy production of melatonin (sleep hormone) and cortisol (alertness hormone).

The artificial light we use indoors is static; it doesn’t change in the same way that natural light changes due to:

The day-night cycle
Seasonal variation
Weather patterns
Global latitude

Artificial light disrupts our natural sleep-wake cycle whereas HCL works in closer harmony with our biological rhythms. Humans need dynamic light that mimics the light we see in nature – from dappled sunlight, to full midday sun, to glowing evening campfire – in order to optimally regulate our hormones and promote our general wellbeing.

The Benefits of Human Centric Lighting

Scientific studies are showing that HCL:

1. Improves natural sleep cycles which:

Promotes patient recovery in hospitals
Improves traveller jet lag in hotels

2. Encourages better mood regulation in those affected by:

Mental health issues
Seasonal Affective Disorder (SAD)
Dementia

3. Promotes health and wellbeing by providing:

Better visual comfort
Less eye strain & headaches
Reduced cases of myopia (short-sightedness) in children

4. Increases productivity and focus by:

Enhancing alertness in offices & schools
Supporting shift workers during irregular working hours

HCL promotes better sleep, mood regulation, visual comfort & productivity.

How to Create a Human Centric Lighting System

Implement clever design, including:

All the fundamentals of great lighting design e.g. visual comfort, glare control & layers of light
Considering each individual environment, who uses it & how it is used
Daylight integration with artificial light
Lighting vertical surfaces, as well as horizontal
Measuring how much light reaches the eye (not just the desk surface)

Utilise smart products, such as:

This smart technology allows for a dynamic lighting system by adjusting:

Light colour, e.g.:

Cool white light (5000–7000K) boosts alertness
Warm white light (2700–3500K) supports relaxation & sleep

Light intensity:

Both light intensity and duration of exposure affect biological response
E.g., research recommends our eyes are exposed to 250 melanopic lux for 30 mins in the morning to regulate our sleep cycles effectively

Animation of a dynamic Human Centric lighting system in a contemporary kitchen throughout the day.

Research, technology and best practices are still evolving, so it’s essential for HCL systems to be flexible in order to adapt to any changes necessary.

HCL – The Future of Lighting Looks Healthy

Human Centric Lighting represents a move towards healthier, human-focused architectural design (it’s now included in the WELL Building Standard criteria). The mainstream demand for blue light glasses and infrared light therapy demonstrates our growing awareness of the whole spectrum of benefits that light has to offer - beyond the visible. And when lighting supports your biology, life feels just that little bit brighter.