http://vitanetonline.com/forums/1/Thread/289Have the gray skies of winter got you singing the blues? Do you feel tired, lost your creative spark, need extra sleep, can't get control of your appetite? If you nod in agreement to these queries, you may be one of the millions of people affected by SAD (seasonal affective disorder), also known as the "winter blues" or "cabin fever." Time to lighten up, throw off those lowdown winter blues and step up to more enjoyable feelings. Experts who study the winter blahs now acknowledge that you can blame much of winter's crankiness, moodiness and restlessness on short, cloudy days and a lack of sunlight. Low levels of sunlight trigger changes in hormones, increasing levels of melatonin (a hormone that normally helps you go to sleep) and decreasing serotonin (a hormone that improves mood). For many people, this hormonal tumult translates into a craving for sugary foods, a need for more sleep and a reduced sex drive.
Walking in natural light can banish these problems, and research finds that natural light frequently offers the best results (Journal of Affective Disorders 1996 Apr 12; 37(2-3):109-20). In this study, people either participated in a daily walk outdoors in natural light or were treated for half an hour in artificial light. At the end of the study, participants were tested for melatonin and cortisol (stress hormone) levels. Both were found to be lower after exposure to natural light than artificial light.
Roll up those sleeves when you're outdoors this winter: Curiously enough, studies show that light produces physiological effects by being absorbed through both the eyes and the skin.