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Understanding Seasonal Depression

How to Prevent Seasonal Depression
Regular exercise and spending time being social both help stave off bouts of seasonal depression.
Regular exercise and spending time being social both help stave off bouts of seasonal depression.

Unlike many other forms of depression seasonal depression has an identifiable trigger, the change of seasons. And if you understand what's causing your seasonal depression, you may be able to get ahead of the symptoms before their seasonal onset or before they worsen.

There are several factors that have a role in the onset of depression, and for the seasonal type of the disorder, where you live, your hormones and your genes are considered three big influencers.

First let's look at your environment. Seasonal affective disorder becomes more common the farther away from the equator you live. For example it's a rare illness among people who live in the tropics (within 30 degrees north or south of the Equator) but travel 38 degrees north of the Equator to Washington, D.C., and you'll find roughly 4 percent of people suffer from symptoms of SAD. Keep heading north to Alaska, more than 60 degrees north of the Equator, and the number of sufferers jumps to almost 10 percent of the population [sources: Mental Health America, The Cleveland Clinic]. What's so special about living in the tropics? Daylight, a lot of it, and all year long.

There are two key components playing a role in the cause of SAD: changes in the amount of exposure to daylight and hormone imbalances. But how do these factors cause depression? No one is sure yet. There are many possibilities that boil down to two theories:

One is that a lack of sunlight may be bad for yourbiological clock. Your biological clock does more than give you jet lag and remind you you'll soon be too old to have biological children; it's your body's clock. The internal systems of your body all set their watches against the body's biological clock, so if the clock is broken, your body begins to less effectively regulate your mood, your sleep patterns and your hormones (including serotonin, a neurotransmitter associated with mood, and melatonin, which is associated with sleep). This theory suggests that by boosting your exposure to light you can reset your clock.

The second approach suggests that people suffering from SAD may have a chemical imbalance (again, serotonin and melatonin) not caused by a lack of exposure to light but rather best treated with exposure to light.

Working with what research has shown us so far, we have no way of preventing or curing depression, but often the symptoms of the illness can be managed. And those suffering from recurrent seasonal-onset depression may benefit from taking small preventative measures before any symptoms begin, either in the early autumn for winter onset or early spring for summer-onset SAD.

A few low-impact daily changes such as spending time being social to boost your mood and eating a well-balanced diet to help keep those carb cravings at bay may be helpful for some people, and if you're not already getting at least 30 minutes of exercise at least three times a week consider talking to your doctor about the benefits of starting a new workout. Exercise not only helps combat winter weight gain but is also a great way to boost your mood. Make extra effort to spend time outside every day, and be alert for symptoms so there's no delay in getting treatment if needed.