A simple 15 minute walk outside during lunch does wonders, as well as vitamin D gel caps, every day to balance the mood.

The walk midday gets one into the daylight, as well as creating positive endorphin's, and the vitamin D evens out the mood.

Whist many go to work in the dark, stay within their own work space, not seeing the light during the daylight hours, and going home in the dark, a simple walk during their lunch hour does wonders for the soul, even moreso than the meal that said hour, or half hour it may represent.

Mine own advantage is as a medical courier, I am out and about all day, and therefore do not suffer unto the lack of daylight at all, as I am out within it all day long, and do feel most fervently unto those that are stuck inside for the most part of the day, which is why I recommend the lunchtime walk, at least, unto those that work the daytime shift indoors.

There is daylight, and sunlight, even within the winter, should one wish to experience it as they can.