Yes. Depression is a disease.
Disease, a harmful deviation from the normal structural or functional
state of an organism.
Your statements and questions...
When a person is depressed, is it
because the brain is malfunctioning,
or is it just a natural reaction for
There is a big difference between feeling depressed (or sad) for a few days and having a depressive disorder. See below.
Today you say to a doctor that you are
sad, and he prescribes you an
antidepressant without asking further
Wildly unethical behavior by doctors has no effect on the status of depression as a disease.
By a natural condition I point out the
Basel study saying that people get
more analytic during a depression. It
is the way that the brain found to
protect the person from getting
There are many hypotheses on the exact cause of depression.
From your link....
The results of the study give weight
to one American theory on depression,
which sees the mood disorder as an
adaptation to solving complex
NOTE: The authors understanding of what constitutes a "theory" is incorrect.
This is, most likely, a reference to the idea of analytical rumination (one of the evolutionary approaches to depression).
The analytical rumination (AR)
hypothesis proposes that depression is
an adaptation that evolved as a
response to complex problems and whose
function is to minimize disruption of
rumination and sustain analysis of
...evidence suggests that much of what
is currently classified as depressive
disorder represents normal
psychological functioning (Horwitz &
Wakefield, 2007). One likely factor
contributing to overdiagnosis is that
clinically significant impairment is
not conclusive evidence of disorder
(Spitzer & Wakefield, 1999).
Impairment can be caused by biological
dysfunction, but it can also be caused
by properly functioning stress
The AR hypothesis suggests that
psychotherapies are productive when
they help depressed people identify
and solve important problems in their
lives. It also suggests that
depressive rumination is useful and
that antidepressants may interfere
with the ability to ruminate. For
these reasons, the AR hypothesis would
place greater emphasis on
psychotherapy and less on medications.
Depression as an adaptation for analyzing complex problems.
Terminology is inconsistent in this
area. Those who see depression as
intrinsically pathological tend to
reserve the word for severe states
that are mostly unrelated to ordinary
mood variation, while those who see it
as a defense use the same word to
cover a wide range of normal and
Is Depression an Adaptation ?
In other words: Semantics might cause confusion.
Taken from my answer to Do antidepressants work ? See also: Is there any scientific basis for Seasonal Affected Disorder (SAD)?.
When a person has a depressive
disorder, it interferes with daily
life, normal functioning, and
causes pain for both the person with the disorder and those who care
about him or her.
(Emphasis mine.) **
General forms of depressive disorder...
- Major depressive disorder, also called major depression, is
characterized by a combination of
symptoms that interfere with a
person's ability to work, sleep,
study, eat, and enjoy once–pleasurable
activities. Major depression is
disabling and prevents a person from
- Dysthymic disorder, also called dysthymia, is characterized by
long–term (two years or longer) but
less severe symptoms that may not
disable a person but can prevent one
from functioning normally or feeling
- Psychotic depression, which occurs when a severe depressive illness is
accompanied by some form of psychosis,
such as a break with reality,
hallucinations, and delusions.
Source: National Institute
of Mental Health
Brightblades answer also has some excellent information on depression.
The Bottom Line...
Some manifestations of disease arise
directly from a defect in the body’s
machinery while others are defenses or
dysregulations of defenses...defenses
such as pain or diarrhea are
adaptations shaped by natural
selection. Dysregulated or extreme
defenses cause many diseases, such as
chronic pain or dehydration from
Source: Is Depression an
If "depression" is an evolutionary adaptation...
The disease caused by its dysregulation, currently known as depression, will need a new name.