Direct sunlight provides between 70,000-100,000 lux of brightness. Even in the shade there is still 2,000-10,000 lux.
We know that the right quantity and quality of light is essential to regulate our human organism, provide vision and enhance wellbeing.

Our living rooms and lounges are lit to considerably lower levels usually between 100-250 lux. We expose older people and particularly those suffering with dementia to half this amount of light, because of their maturing eyesight, therefore only 50-100 lux will be transmitted onto the retina.

To some degree the human organism is able to adapt to less ideal circumstances, but in most cases older people are subjected to lighting levels that are too low making them feel lethargic, depressed and eventually withdraw under such conditions. “Often only those patients visited by relatives enjoy the luxury of being outdoors in natural light”. (1)

However, it is up to lighting designers and architects to make a positive difference to the design and lighting of older peoples indoor environments and to their lives.

The German poet Johann Wolfgang von Goethe expressed his desire for light in saying: “More light! Give me more light!”


1. Sutherland, D. et al (2004) The Use of Light Therapy to lower Agitation in People with Dementia. Nursing Times; 100: 44, 32–34.

Find out more about the health effects of light deficiency >>

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