Visible light is contained within the electromagnetic spectrum, between infra red and ultra violet energy. This part of the spectrum is visible to the human eye because our eyes contain nerve endings called rods and cones that are sensitive to particular wavelengths of visible light. The rods are responsible for night vision and the cones for distinguishing the colours of light. These wavelengths are measured in nanometres.

Red light is produced by the heaviest, slowest vibration of atoms and Violet by the lightest and fastest.

We absorb different components of sunlight through our eyes and our skin. Thanks to our highly developed and sophisticated eyes, a simple lens can direct light onto photosensitive cells allowing us to see many colours. The optic nerves carry information from the eyes in the form of electrical nerve signals that travel to a region of the brain known as the visual cortex. The hypothalamus is situated in the brain. It works with the pituitary gland to control most of the endocrine glands in the body. It plays a part in controlling body temperature, metabolism, and water regulation plus sexual and reproductive functions.

The pineal gland is frequently described as the light meter of the body. The gland’s secretions are determined by the number of sympathetic nerve impulses reaching it. The pineal gland produces an important hormone called melatonin. Melatonin plays a crucial role in sleep, immunity and sexual maturation. The production of melatonin is directly affected by the amount and the timing of exposure to light. The greatest amount is produced when we are asleep. Serotonin is another chemical which functions as a chemical nerve messenger transmitting messages through specific circuits and centres within the brain. Low levels of serotonin have been linked to a variety of psychological disorders including Seasonal Affective Disorder (S.A.D.), eating disorders and depression. Lack of exposure to natural light can lead to ‘light starvation’ which includes general stress symptoms, fatigue, depression and hyperactivity in children, difficulty in concentrating. Inadequate exposure to sunlight results in weak bones because of reduced levels of vitamin D production.

The bright colours of natural fruit and vegetables are often directly linked to their nutritional value.

The aromas of essential oils, flower essences and herbs also have an important link with colour and our wellbeing.

The use of colour and light is not new to medicine and well-being. It has been used for thousands of years by the Egyptians, Chinese, Indian and Greek cultures.

Our own hospitals know the power of shining violet light on jaundiced babies and of laser light treatments in performing operations. . Colour gives us clues, aids discrimination and memory and keeps us safe. It affects our mood, state of mind and how we relate to others around us. The colour we decorate our homes, work places, schools, bedrooms all have a bearing on our mood and our behaviour. The importance of good lighting systems in schools and work places is only just being recognised.

Sound also vibrates at certain frequencies which like the vibrations of light have an effect on our mental, emotional, metabolic and physical well-being.

It is simply not possible to be indifferent to colour whilst we live and breathe on this planet.