Light has been revered since the dawn of time, or rather its main source: the Sun.
Considered the very essence of life, abundance, eternity and wisdom, the Sun was once deified by ancient civilizations such as Egypt, India, China, Rome and the Aztecs.
Beyond its high spiritual power, the Sun and its light were also used for medicinal purposes, a practice known as heliotherapy . It is plausible to believe that similar knowledge existed among ancient peoples.
The ancient Egyptians, as early as 2600 BC. BC, held profound medical knowledge related to light. A testimony attributed to Imhotep, the legendary architect and great sage, reveals medical formulas illustrating an advanced understanding of the effects of light. This ancestral document foreshadowed modern chronobiology by attaching particular importance to the appropriate time of day for each treatment, in harmony with the solar cycle. He also described the use of solar rays to sterilize food and potentiate pharmaceutical preparations through photochemistry .
The Greeks, also fervent followers of heliotherapy, established an indisputable link between light and health. Around 450 BC. BC, the great historian Herodotus already mentioned the existence of solariums, places of healing based on solar light. According to Hippocrates of Kos , considered the father of medicine (460-370 BC), light and its heat were of paramount importance in treating various ailments such as rickets, obesity and metabolic disorders.
The Romans, cultural heirs of the Greeks, perpetuated this special bond with light. Roman law included clauses guaranteeing a "right to light" in Roman houses, most of which had solariums.
Soranos of Ephesus, one of the great Roman physicians of the 2nd century, prescribed sun exposure for infants with jaundice. It is thus considered the ancestor of modern treatments against neonatal jaundice, which today use blue light for therapeutic purposes.
Source: A. Martel, The Power of Light