Does the rain really affect your mood?

Have you ever noticed how a gray, rainy day makes you feel gloomy and tired, but a sunny day can leave you feeling cheerful and energized? Well, there's a scientific reason for this. Insufficient exposure to sunlight has been associated with low levels of melatonin and serotonin, carbohydrate craving, weight gain, and sleep disturbance.

Some of you may have also noticed that you find a seasonal fluctuation in your moods, feeling depressed only in the winter months. Take a look at your calendar and you'll soon see why. Each year on June 21 we experience the summer solstice, the longest day of the year. With our longest hours of sunlight in the middle of summer it's no wonder we're happier this time of year. After this date, however, the days progressively get shorter until the winter solstice on December 21, the shortest day. Is it any accident then that so many of us run for the hills when the holidays roll around? With our serotonin in such short supply, the added stresses of living up to our images of the picture-perfect holiday are just too much. The medical term for the season-long malaise that we fall into is seasonal affective disorder, or SAD.

SAD is believed to be caused by a disturbance in the normal circadian rhythm of the body. Light entering through the eyes influences this rhythm. When it is dark, the pineal gland produces a substance called melatonin which is responsible for the drowsiness we feel each day after dusk. Light entering the eyes at dawn shuts off the production of melatonin. During the shorter days of winter, when people may rise before dawn or not leave their offices until after sunset, these normal rhythms may become disrupted, producing the symptoms of SAD.

There is also evidence linking SAD to a reduced amount of the neurotransmitter serotonin. Serotonin is the feel-good substance that is increased by antidepressants called selective serotonin reuptake inhibitors (SSRIs). This decrease in serotonin production may be responsible for many of the symptoms of SAD, such as depression and carbohydrate cravings.

That is why Sunshine is always good for us all. Get out and enjoy the Sun. Life is too precious to be depressed.