Written by Aruna Nathan, M.D.
February 7, 2015
Overcome Seasonal Affective Disorder (SAD)
As we are in the peak days of winter and have less and less natural light, it’s important to talk about SAD or Seasonal Affective Disorder. There are two types of SAD, namely fall onset SAD and spring onset SAD. The fall version usually affects an individual in late fall or early winter and the spring version affects in early spring although it is less common. Note that SAD affects more than half a million Americans annually.
Fall onset SAD may be characterized by an increased need to sleep, increased appetite with carb cravings, weight gain, irritability, interpersonal difficulties and feeling of heaviness in the arms and legs. These changes affect many aspects of our life, and therefore should be recognized and addressed. The diagnosis is made if these symptoms occur at least two years in a row in the winter months. With SAD, your symptoms are more of atypical depression as mentioned earlier (craving carbs, increased sleep, weight gain). It is also useful to record your symptoms on a calendar. You should discuss your symptoms with a health care provider to help make the diagnosis of possible SAD.
The incidence of fall onset SAD is significantly greater in higher latitudes compared to that in the lower latitudes. Decreased daylight time is therefore a strong predisposing factor. In the U.S., the prevalence of SAD ranges from 9.7% in New Hampshire to 1.4% in Florida.
No studies have proven the exact cause of this condition, but there is evidence to suggest the role of sunlight. The amount of sunlight affects the quantity of impulses generated in the brain. This in turn probably affects the amount of neurotransmitters that can affect your mood, like serotonin and some hormones like melatonin.
SAD affects both women and men. The average age of people who develop SAD for the first time is 23 years old but people of all ages can develop it. Fall onset SAD starts in late fall or early winter and most symptoms do tend to improve during the spring and summer months. The symptoms are worse during the coldest months.
Light therapy
Bright light tends to improve symptoms of SAD. Getting this light exposure as early in the mornings as possible seems to work best.
This can be achieved with sitting in front of a special light box for a session each day, while eating breakfast, reading the newspaper, checking your morning emails or any desk work. These special light boxes are sold in general stores. They come in various shapes and sizes. You usually sit 3-4 feet from the light box; you face it but you do not directly look into it. About 20 minutes exposure on average is needed.
Some people use dawn simulators instead, or along with, a light box. Dawn simulators are devices that slowly increase the amount of ambient light in the room, taking anywhere from 60-90 minutes to simulate sunrise prior to or when you would wake up. This can be achieved with simple, small devices to very sophisticated machines like a computer-controlled heliostat that reflects sunlight into the windows of a home.
Some people with SAD may have an immediate response to light therapy though typically it may take 2-4 days to see a positive response. If symptoms improve, then the use of light therapy should continue until mid-Spring. It may take longer to see the effects for some people, and yet others may need additional modalities including therapy, melatonin and anti-depressants. Light therapy does not work in every case but many will have positive results. If symptoms do not improve in 4-6 weeks, other modalities of treatment should be considered.
There is always a theoretical risk for eye or retinal damage with any light exposure but the light emitted by the light boxes do not contain UV light, which is the main part of sunlight that is damaging to the skin and the retina. Always look for possible side effects like headaches, irritability, or lack of sleep, especially if light therapy is used in the evening hours.
You should always discuss light therapy with your doctor before starting, but especially if you have retinal disease, macular degeneration or you are on medications that increase your sensitivity to light (some common antibiotics, anti-hypertensive medications or cancer medication).
It is also helpful to exercise regularly to release the feel-good endorphins and eat a diet rich in a variety of fruits and vegetables.
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Tags: depression, SAD, seasonal affective disorder