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Winter Blues? It Could Be Seasonal Affective Disorder

Understanding, Diagnosing and Treating SAD

Do you find yourself thriving every summer, only to begin crashing as fall descends and heading toward full-scale depression around the holidays? If so, you're not alone. Seasonal affective disorder (SAD) is a seasonal mood disorder that yields symptoms similar to those associated with depression. Unlike basic depression, though, SAD occurs around the same time each year. If you find you're feeling miserable just as you're preparing to celebrate the holiday season, the right treatment can make a big difference in your life.

What is Seasonal Affective Disorder?

Seasonal affective disorder is more than just a case of winter sadness. Everyone experiences periodic struggles during the winter. For some, it manifests in the form of sadness over missing family members, while others find themselves experiencing extreme cabin fever. For people with SAD, though, a change in seasons makes it nearly impossible to function. If you have the following symptoms, and those symptoms occur cyclically around the same time each year, you may have SAD:

• Feelings of depression, sadness, guilt, hopelessness, or worthlessness

• Being unable to enjoy activities you once loved

Procrastination, distraction, and difficulty focusing

Anger. While anger is not a “traditional” depression symptom, some people respond to SAD with anger and irritability toward loved ones; this is especially common among men.

• Changes in sleep habits. You might have trouble falling asleep, or find that you spend much of your day sleeping or tired.

• Changes in weight or eating habits

• Withdrawing from social activities

• Craving foods high in carbohydrates

• Inability to tolerate stress

If you find that you have these symptoms year-round, depression might be a more appropriate diagnosis. If you experience these symptoms interspersed with symptoms of mania and high energy, it could be bipolar or cyclothymic disorder.

What Causes Seasonal Affective Disorder?

To understand seasonal affective disorder, it's important to understand both its immediate causes and risk factors. Researchers aren't fully certain what causes seasonal affective disorder yet, but evidence points strongly toward changes in daylight. During the winter months, you have less access to UV rays. While researchers aren't sure why, this change can trigger depression in some people, possibly because of sudden shifts in the body's circadian rhythms.

Some evidence also points to the role of melatonin, a hormone that plays a role in sleep. During the winter months, when there are more dark hours, the body increases its production of melatonin. In some people, this may trigger increased sleepiness and decreased energy, leading to feelings of depression.

Behavioral changes during the winter months may also trigger SAD, but usually only in people who are already vulnerable to the disorder. Some people, for example, experience a post-holiday depression because they're sad about returning to everyday life or regretful about debts they incurred buying holiday gifts.

As with most mental health conditions, there appears to be a genetic correlation to SAD, though researchers have not yet uncovered the precise mechanism. If you have depression or mental illness runs in your family, you are more vulnerable to SAD. Of course, this could also be due to learned behaviors that increase your likelihood of getting depression SAD, but in either case, a family history makes you more likely to get the disorder.

One recent study found that SAD was more prevalent in people with decreased serotonin. These people secrete higher levels of a serotonin transporter protein during the winter, according to the data. The protein, known as SERT, is correlated with lower levels of serotonin, a neurotransmitter that is also implicated in major depression. Consequently, restoring serotonin levels to normal may help some people combat SAD.

Risk factors for SAD, by contrast, don't cause the disorder by themselves, but they do increase your risk of developing it. Risk factors include:

• Experiencing a trauma or tragedy during the winter months. People who have lost a relative or suffered a life-altering event during the winter months may be triggered by memories of this event to become depressed each year.

• A history of stressful or chaotic family holiday events; some people have families that are so dysfunctional that simply spending time together – or contemplating spending time together – makes them more vulnerable to depression.

• Living far away from the equator, where there is less sunlight and therefore fewer UV rays.

Sex. Women are more likely to develop SAD, but men appear to have more serious symptoms when they get it.

• Age. SAD is more common among young people.

• Having a history of depression or bipolar disorder.

How Is Seasonal Affective Disorder Treated?

SAD can mimic the symptoms of health conditions such as mono and thyroid disease, so a trip to your doctor is of paramount importance if you think you have SAD. Only your doctor can rule out other causes and treat underlying health conditions that may contribute to your symptoms. It's also important to let your doctor know whether your symptoms are chronic or cyclical, since SAD is frequently misdiagnosed as depression or bipolar disorder.

If you have SAD, light therapy is one of the most effective and least costly solutions. With light therapy, you'll sit under an artificial light for a short period of time – usually 15 to 30 minutes – each day. In many people with SAD, this is sufficient to reduce symptoms.

More serious cases may necessitate medication. Drugs that boost serotonin, including many anti-depressants, can be highly effective. Combining medication with therapy, though, is the most effective option because in so doing, you'll learn key coping skills while getting help with a chemical imbalance. SAD can ruin the holiday season and make you dread winter, but you don't have to suffer with it forever. Treatment works.


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