Does Winter Make You S.A.D.?
It is estimated that 10 million people in the United States alone experience the
effects of Seasonal Affective Disorder (SAD), while another 25 million suffer
from a milder version sometimes referred to as winter depression.
Dr. Norman E. Rosenthal , of the National Institute Of Mental Health in
Bethesda, Maryland, spearheaded research in the disorder in 1980 when he
noticed patients became severely depressed in the winter but snapped out of it
in the spring. He also noticed that some patients from the North brightened
when they visited a southern climate, but experienced a relapse when they
returned home. Since then, dozens of research psychiatrists and doctors have
analyzed SAD, finding that light can influence moods, possibly because it
produces an increase in a hormone called melatonin which can cause depression
when present in large amounts. It is believed that production of this hormone
decreases when the body is exposed to sunlight.
Dr. Rosenthal describes the symptoms of SAD in his book, Winter Blues.
Typically, the symptoms last from early November, when the days become
noticeably shorter, until March, when days begin to lengthen. January and
February are the worst months for depression. Women are about four times more
susceptible to SAD than men. This may be related to hormonal differences.
Symptoms Of SAD (In addition to suffering from depression that can last for
• Crave carbohydrates (starchy foods) and sweets and feel better after eating
• Gain Weight
• Sleep longer hours but wake up feeling tired
• Lose interest in sex.
• Feel overwhelmed by insignificant things
• Avoid family and friends
• Have difficulty thinking and concentrating
• Feel achy and suffer from frequent infections
Studies have shown that during fall and winter about 20% of the population is
affected by fatigue, irritability, anxiety, weight gain, social withdrawal, and
a lack of alertness. Most affected are those living in northern latitudes and
in frequently overcast areas, especially during the shortened fall and winter
days. About 75% of those affected are women.
Bright Light Therapy Treats SAD
According to Dr. Robert deVito, chairman of the Department of Psychiatry at
Loyola University Medical Center in Maywood, Illinois, 60% of the adult
population experiences some change in mood and behavior linked to the seasons.
But in most cases the problem is easily solved. DeVito reports an 80% recovery
rate in his patients when full-spectrum light therapy is used. Light therapy
evens out the mood swings, decreases the need for sleep, and lessens the
cravings for carbohydrates. "The full-spectrum lights give the body the
equivalent of a longer day and lift the mood considerably," deVito explains. "
Ordinary interior lights won't do," he adds. "You need light 10 times as
bright, light that imitates sunlight, without the intensity of the sun's rays."
One of the most effective methods of treatment is a device known as a
"lightbox." Designed to simulate the brightness of the sun as it is in the
midmorning hours of springtime, the light boxes trick the body into believing
it is no longer winter. The light from a lightbox may range between 2500 to
10,000 lux, (a lux is a standard unit of measurement for light brightness).
This compares with the usual 500 to 700 lux in an ordinary well-lighted room
and up to 100,000 lux outdoors on a bright day.
The lightbox provides a measured amount of balanced spectrum light equivalent to
standing outdoors on a clear spring day. This has been shown to help regulate
the body clock. Photobiologists point out that the light is registered by the
eyes through the retina, which then transfers impulses to the hypothalamus in
the brain to normalize the body clock function. The light from the box will
help synchronize sleep/wake patterns with ones work and lifestyle. Exposure
time is determined by the intensity of the light source. Although there are
individual differences, a 1/2 hour treatment at 10,000 lux per day (usually
during the morning hours) is the average.
Portsmouth, N.H. psychotherapist Stephen Little treated more than 250 of his
patients with light boxes. "As opposed to antidepressants, which can take as
long as a month to know if they are working," according to Little," light
therapy can take from one to five days and with no side effects." He said if
SAD sufferers sit in front of a lightbox for 30 minutes each morning, the light
almost instantly makes them feel better.
As reported in Sciencenews.org (Mood Brighteners: Light Therapy Gets Nod As
Depression Buster by Bruce Bower 4/05), A research review commissioned by the
American Psychiatric Association in Washington, D.C., concluded that in trials,
daily exposure to bright light is about as effective as antidepressant drugs in
quelling seasonal affective disorder (SAD), or winter depression, and other
forms of depression.
"I now tell my patients that light therapy is a reasonable depression treatment,
even if the data base for this approach is relatively small," says psychiatrist
Robert N. Golden of the University of North Carolina at Chapel Hill. Golden
directed the new statistical review, which appeared in the April American
Journal of Psychiatry.
Like many mainstream psychiatrists, Golden had been skeptical of studies
reporting that depression diminishes in response to daily bright-light
exposure, usually administered early in the morning for 30 minutes to 1 hour.
Can Light Therapy Treat Bi-Polar Disorder?
Bipolar disorder is also known as manic depression because of extreme swings in
mood, thought and behavior. Bipolar is different than major depression in that
it is marked by episodes of euphoria or mania. These episodes commonly last
from hours to days, but can also last for months. Bipolar Disorder afflicts 2
million adults, and possibly another 1 million plus children. It usually starts
in adolescence, with males first experiencing a manic episode and females
experiencing a depressive one.
There are two types of bipolar illnesses, bipolar 1 and bipolar 2. Bipolar 1 is
more severe than bipolar 2, and is marked by one or more manic swings followed
by one or more major depressive episodes. Bipolar 2 generally starts with one
or more depressive episodes, followed by a milder (hypomanic) episode.
Symptoms Of BiPolar Disorder
The depressive symptoms are similar to major depression. Mania symptoms may
include some of the following:
• Heightened mood
• Excited behavior, increased energy or activity
• Aggressive behavior and/or irritability
• Lack of desire for sleep
• Impulsiveness or poor judgment, reckless behavior
• Racing speech, thoughts, etc.
• Overly optimistic, egoistic, delusions of grandeur
• Hallucinations (extreme mania)
The medical journal The Lancet reports that the lack of bright light like
sunlight may be a cause of depression. Bright light produces serotonin in our
brains, and scientists believe that low levels of serotonin contribute to
depression. As light produces serotonin, our natural balance returns, and we're
productive again. Clinical studies at Yale, UCSD and others, have shown
dramatic results using bright environmental light (10,000 lux intensity).
Light vs. Anti-Depressants
The discovery that light produces serotonin is significant, because it may be
the only way to increase serotonin levels in the brain. Pharmaceutical
companies have never been able to replicate this process. Anti-depressant
medications are designed to keep serotonin in the system, but they cannot
produce it. For those who already have low levels of serotonin, SSRI's are not
as effective as they otherwise might be. This is why light may be a beneficial
supplement. Recent studies suggest depression may be more effectively treated
with light and medication rather than medication alone.
Light Therapy Treatment for Bipolar Disorder
Specialized bright light is known as an effective antidepressant. Because most
bipolar patients suffer from depressive episodes during the winter and in
overcast conditions, researchers feel that light therapy should be an obvious
choice for manic depression. Several studies have demonstrated the success of
light therapy in averting depressive episodes in manic depression. In January
2004, the Cochrane Medical Review recommended light therapy for treating
Light appears to be successful for two reasons: First, bipolar patients suffer
from low serotonin levels during depressive lows, and second, they are also
supersensitive to melatonin fluctuations. Since light effectively regulates
melatonin and serotonin, bipolar patients respond almost immediately.
Light Therapy & Bipolar Children
Because light therapy poses no long-term negative side effects, it is also
recommended for children. One of the more accurate works on childhood bipolar
disorder, The Bipolar Child, recommends light therapy as a first line
Precautions With Light Therapy and Bipolar Disorder
Researchers have noted that manic depression sufferers (bipolar 1) should be on
an effective mood stabilizer before using light therapy. Because light produces
serotonin, it may precipitate a manic reaction. Light has been found to be safe
when used for less than an hour at a time, but physician supervision is always