SUNLIGHT REDUCES FATIGUE ...
SUNLIGHT also CURES SAD (* seasonal affective disorder) AND REDUCES STRESS...
SUNLIGHT AFFECTS HORMONES' LEVELS...
According to the Markandeya Puran, the Sun is the embodiment of Brahma, the world originates from the Sun and is established in it.
The passage of Krama-Mukti, the gradual liberation of the soul attained by Saguna-Upasanas, or qualitative meditations, is always traversed through the sun. The sun is regarded as a very important place, a halting point of the soul in the gradual ascent to the Absolute. Of all the deities who are supposed to direct the soul onwards in its passage upwards, the sun is considered the most important. It is a very prominent location where the soul is not only purified in an intensive manner but is landed in the realm of light as it finds itself in the region of the sun.
[24:35] GOD is the light of the heavens and the earth. The allegory of His light is that of a concave mirror behind a lamp that is placed inside a glass container. The glass container is like a bright, pearl-like star. The fuel thereof is supplied from a blessed oil-producing tree, that is neither eastern, nor western. Its oil is almost self-radiating; needs no fire to ignite it. Light upon light. GOD guides to His light whoever wills (to be guided). GOD thus cites the parables for the people. GOD is fully aware of all things.
[6:74] Recall that Abraham said to his father Azar, "How could you worship statues as gods? I see that you and your people have gone far astray."
[6:75] We showed Abraham the marvels of the heavens and the earth, and blessed him with certainty:
[6:76] When the night fell, he saw a shining planet. "Maybe this is my Lord," he said. When it disappeared, he said, "I do not like (gods) that disappear."
[6:77] When he saw the moon rising, he said, "Maybe this is my Lord!" When it disappeared, he said, "Unless my Lord guides me, I will be with the strayers."
[6:78] When he saw the sun rising, he said, "This must be my Lord. This is the biggest." But when it set, he said, "O my people, I denounce your idolatry.
[6:79] "I have devoted myself absolutely to the One who initiated the heavens and the earth; I will never be an idol worshiper."
Peace be upon you