The protein, according to the study published in the Archives of General Psychiatry, clears serotonin from the brain. Serotonin is a chemical messenger that regulates mood, energy levels and appetite.
Jeffrey Meyer, leader of the research team, wrote, "This offers an explanation for why some healthy people experience low mood and energy in the winter and why there is a regular reoccurrence of depressive episodes in the fall and winter."
Serotinin have long been suspected as responsible for the mood swings, but scientists could not pinpoint the biological mechanism that causes the change in levels of the chemical messengers. The research identified it as the serotonin transporter, which removes the chemical from synapses or communication links between nerve cells.
Some patients suffering from seasonal affective disorder are being treated by exposing their eyes to rays of light for certain periods during the winter months, but it does not work for all SAD sufferers. With the findings, researchers may consider changing the light intensity or length of the treatment to produce better results.
Meantime, as Canada officially starts spring this week, Environment Canada issued its forecast for the forthcoming winter. Toronto would enjoy warmer weather than normal, but Ottawa, British Columbia and Quebec will have a colder than normal winter.
The reliability of the predictions will become more accurate as the winter days approach. Senior climatologist David Phillips admitted to the Toronto Star, "The users of those forecast will take a peek at it but I don't think many users make million-dollar decisions based on that - at least they shouldn't."
