Sunlight helps regulate your
internal biological clock.
When there are changes
in the amount of light you
get, that clock gets out of
balance.
5
DOES YOUR MOOD
seem to mirror the seasons—maybe grow
darker as the fall and winter days get shorter and lift as the brighter days
of summer approach?
You could have a condition known as seasonal affective disorder (SAD)—a
type of depression that’s related to seasonal changes in light. SAD can make
you feel tired, crave carbohydrates, gain weight, avoid things you normally
enjoy or withdraw socially during the fall and winter months.
Sunlight helps regulate your internal biological clock. When there are
SEASONAL AFFECTIVE DISORDER
Shed some
light on winter
mood changes
changes in the amount of light you get, that
clock gets out of balance and levels of mela-
tonin, a sleep-related hormone, can increase.
This hormone has been linked to depression.
Both children and adults can get SAD.
However, it usually develops between the
ages of 18 and 30. Women are affected at
about three times the rate of men. Some
evidence suggests that the farther you live
from the equator, the more likely you are to
develop SAD.
Although SAD is generally considered a
fall and winter disorder, in a small number
of cases symptoms may occur in the sum-
mer. Some people also experience symp-
toms during periods of overcast weather,
regardless of the season.
Shining a light
A diagnosis of SAD is based on your symp-
toms and history. Symptoms of SAD must
return every winter for three consecutive
years and then completely disappear in the
spring and summer.
If you have SAD, getting more sunlight
may make you feel better. It might be help-
ful to take walks outdoors or to place your-
self near a window during the day when at
home or work.
If your symptoms are particularly bother-
some, light therapy may be recommended.
This involves using special lighting while
indoors. Therapeutic lighting is much more
intense than standard lighting and has been
shown to decrease levels of melatonin in
the brain.
Your doctor can help you decide how
long to spend in this lighting and the best
time of day to do so. For many people
with SAD, light therapy is very effective.
However, if it doesn’t work for you, your
doctor may have other suggestions, includ-
ing taking medicine for depression.
Sources: American Psychiatric Association; Mental Health America
