The
Hunter-Gatherer Cure for Depression
Human bodies have not evolved fast enough to adapt to the
demands of modern life. So believes psychologist Stephen Ilardi,
PhD, author of The Depression
Cureand associate professor of clinical psychology at
the University of Kansas. Although we’re living longer and
theoretically have better health care, the risk for serious
depression has been increasing for more than a century. The
disorder now afflicts one-quarter of Americans (a trend mirrored
across most of the developed world), and has more than doubled
over the past decade alone.
Dr. Ilardi told me that he has long puzzled over the epidemic of
depressive illness, which continues to worsen despite the
widespread use of antidepressant medications. In fact, the risk for
depression is high throughout the industrialized and modernized
world, but low among traditional and aboriginal cultures.
Interestingly, modern-day aboriginal peoples enjoy dramatically
lower rates of many forms of illness that commonly afflict
Westerners -- heart disease, diabetes, asthma, obesity and
allergies among them. Dr. Ilardi believes that we should add
depression to the list of "diseases of modernity."
Our Hunter-Gatherer Ancestors
Until about 10,000 years ago, all humans were hunter-gatherers,
living a lifestyle we know much about from the study of
contemporary foraging groups. Dr. Ilardi’s "aha" moment came while
reading the work of anthropologist Edward Schieffelin, PhD, who
studied the Kaluli, an aboriginal group living in the highlands of
Papua New Guinea. Although the Kaluli have a low life expectancy,
high infant mortality and considerable intergroup violence, Dr.
Schieffelin found that they suffer virtually no clinical
depression. As Dr. Ilardi struggled to make sense of this
surprising finding, he stumbled upon an important insight: the
hunter-gatherer lifestyle features several elements -- ranging from
abundant physical activity to sunlight exposure to omega-3
consumption -- that modern science has shown to be powerfully
effective in fighting depression.
Maybe, thought Dr. Ilardi, the human species never evolved
"antidepressive genes" because our bodies and brains simply weren’t
designed for modern life -- and our brains were protected for
hundreds of thousands of years by the numerous antidepressant
elements of hunter-gatherer life. As an example, Dr. Ilardi cites
the fact that many of the compounds we need for survival aren’t
made by our bodies -- we haven’t evolved the ability to manufacture
them, he says, because we’ve always been able to get them directly
from our diets. Similarly, he theorizes that the human brain has no
ability to stave off depression because until 10,000 years ago --
the blink of an eye in evolutionary terms -- all people lived an
"antidepressant lifestyle." Dr. Ilardi has spent the last four
years developing and researching a treatment program for
depression, Therapeutic Lifestyle Change (TLC), involving six
curative lifestyle elements from the past that he asks his patients
to weave back into the fabric of modern life. The program is
described in depth in his recently published
book, The Depression
Cure.
The Six Elements of an Antidepression Lifestyle
1. Consume abundant omega-3 fatty
acids. Hunter-gatherers ate a much more balanced diet
than we do today, one rich in omega-3 and omega-6 fatty acids in a
ratio of about 1:1. Over the past century, omega-6 fats began to
dominate human fat consumption (due to the use of processed seed
oil and eating meat that was grain-fed), to the point where the
ratio of omega-6s to omega-3s is now about 17:1.Dr. Ilardi’s
advice: Since omega-3 fats have proven antidepressant
properties, take a daily fish-oil supplement that provides at least
1,000 mg of EPA (the version of omega-3 with the strongest research
support in fighting depression).
2. Avoid ruminating on negative
thoughts. Hunter-gatherers lived in the moment --
survival depended on it. A well-researched and effective strategy
for fighting depression encourages people to learn to interrupt
rumination and focus instead on staying in the
moment. Advice: Be continually engaged in what
you are doing and monitor yourself to keep from brooding. Increase
social interaction and shared activities. When you spend time
alone, do things that keep your mind busy, like reading, watching
television, painting, playing a musical instrument or cooking.
Replace ruminative thoughts with positive ones. Write your thoughts
down, and give yourself permission to walk away from them.
3. Get regular sunlight to keep your body clock in
sync. Our ancestors spent much more time outdoors in
the sunlight than we do. Sunlight not only resets the body clock
each day -- necessary for healthy sleep and hormone regulation --
but it also enables us to manufacture vitamin D, which regulates
500 different genes expressed in the brain. Some researchers now
say that most Americans are deficient in vitamin D, which is
strongly anti-inflammatory... and, according to Dr. Ilardi, "a
depressed brain is an inflamed
brain." Advice: 10 to 15 minutes of sunlight
exposure daily between 11 am and 3 pm, depending on your skin
pigment and the time of year, plus take 1,000 IU (international
units) to 2,000 IU of Vitamin D in winter.
4. Stimulate key brain chemicals through physical
exercise. Hunter-gatherers probably were physically
active for three to four hours each day. That may be unrealistic
today, but Dr. Ilardi says that it doesn’t take that much exercise
to fight depression. Research at Duke University found, for
instance, that 30 minutes of brisk walking three times per week was
as effective at alleviating depression symptoms as the
antidepressant Zoloft after four months, and considerably more
effective at a follow-up six months later. By increasing dopamine
and serotonin activity, exercise actually changes the brain
chemistry, says Dr. Ilardi. Advice: 40 minutes
of aerobic exercise three times per week, including 10 minutes to
ramp up and 30 minutes of aerobic (just able to converse)
activity.
5. Emphasize social connection in order to avoid the
harmful effects of isolation. Hunter-gatherers didn’t
spend much time alone. The typical ancient group had between 30 to
150 members, and most worked, cooked and slept together. Nowadays
we are alone a lot -- in our cars, at home,
etc. Advice:Experience in-person community as much as
possible.
6. Increase healthier sleep for brain and body
recovery. Our ancestors got about nine to 10 hours of
sleep each night, but many Americans are somewhat sleep-deprived,
with 30% getting under six hours according to CDC figures. One
recent study from the Stanford University Sleep Lab reported that
most adults feel best after eight or nine hours of
sleep. Advice: Make eight hours of sleep your
goal.The Depression
Cure lists 10 ways to improve your sleep
habits.
Dr. Ilardi is conducting random-control trial research with a
group of people he describes as severely depressed and difficult to
treat. To date, about one-quarter of those on a wait list and
receiving traditional therapy or medication have responded
favorably over a 14-week period. In Dr. Ilardi’s Therapeutic
Lifestyle Change group, approximately three-quarters of the group
have gotten better.
Source(s):
Stephen S. Ilardi, PhD, author of The Depression
Cure, and associate professor of clinical psychology,
University of Kansas, Lawrence, Kansas.