Sunlight plays an effective role in regulating almost all our bodily processes. Sunlight has been shown to increase our sense of well-being and to improve sleep. Ultraviolet light coming into our eyes stimulate the pineal gland, which helps to regulate our Circadian Rhythm (day and night activity cycles). It has been said, "Dark nights and bright days will help keep the hormones in the body functioning properly.
Resting heart blood pressure and respiration rates are all decreased after exposure to sun. This result is especially true if any of them were high to begin with. Blood sugar levels also can be stabilized.
It stimulates the production of more red blood cells, increasing the oxygen and thus increasing muscular endurance and helps the body in maintaining its defense against diseases. Sunlight has even been found helpful in the treatment of stomach ulcers.