A person needs four essential forms of nutrition in the right balance:

Light,
Air,
Heat and
Food.

Too much or too little of all or any one of these can be fatal. With today's technology it is possible to generate and take responsibility for making the right amounts of each available for one's needs.

As Doreen has pointed out there is a lot of information on SAD in our own SAD Forum as well as on the wider www.

Keep Smiling, Go for that walk in the park or out in the daylight even when it is raining, and dream of that holiday in the sun!
Take care.