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Brain--Food
Psychiatrists Explore Use of Nutrients in Treating Disorders
LINKS between compounds in the food people eat and the levels of
certain chemicals in their brains are leading some psychiatric
researchers to suggest that nutritional supplements might be used as
psychiatric drugs.
Carbohydrates like those in spaghetti, for instance, can increase the
level of a brain chemical that can lift depression. And the amino acid
tyrosine, a recent scientific report shows, can buffer the mental and
physical effects of extreme stress.
The current issue of the journal Integrative Psychiatry is largely
devoted to reports that consuming concentrated amounts of
substances ordinarily found in food can affect depression, bulimia
and mania, as well as less serious problems, like insomnia. Several of
the findings, though still controversial, are already in use in the
treatment of these and other psychiatric problems.
Although a few foods appear to directly affect moods and
functioning - particularly carbohydrates when eaten without any
protein - the psychiatrists that use this approach say most people
would not benefit by changing their diets. Researchers are finding
that these nutrients affect the brain when taken in a pure form and
not mixed with others that appear in, say, chicken roast.
The new approach comes from research that shows in great detail
just how the foods we eat affect the brain, and how a given meal
raises or lowers specific neurotransmitters, the chemicals that
transmit signals between brain cells. ''The ability of a meal's
composition to affect the production of brain chemicals distinguishes
the brain from all other organs,'' said Richard Wurtman, a psychiatrist
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at Massachusetts Institute of Technology, who has been the leader in
the new research. ''The crucial compounds that regulate other organs
are largely independent of whatever was in the last meal we ate - but
not the brain.'' Within hours after a meal, the levels of certain
neurotransmitters vary according to the levels of carbohydrates or
proteins that were consumed. That fact, Dr. Wurtman proposed,
provides the psychiatrist with a novel strategy: to use food, or
substances concentrated from it, as they would drugs. The approach
is widely seen as tentative, though promising. The studies are now
largely at the exploratory stage, and many psychiatrists regard the
approach as unproven.
Psychiatric researchers who are following Dr. Wurtman's lead are
focusing on mental disorders thought to involve deficiencies in the
specific brain chemicals most affected by foods. The nutrients that
affect these brain chemicals are mainly among the amino acids found
in all protein.
Researchers have discovered that a handful of amino acids have the
unique property, once they are digested and enter the blood, of
readily crossing the barrier between the brain and most compounds
in the blood. Most of the research has focused on two of these amino
acids, tryptophan and tyrosine.
Tryptophan affects the neurotransmitter serotonin, while tyrosine
affects the catecholimines, dopamine, norepinephrine and
epinephrine, also neurotransmitters. The work also focuses on
choline, which acts on acetylcholine, another neurotransmitter.
Choline is not an amino acid, but is found in the food substance
lecithin.
The new approach is sometimes called ''precursor therapy,'' because
once these nutritional substances reach the brain they act as
precursors, signaling the brain to make more of certain brain
chemicals.
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One of the most recent uses of nutrients focuses on tyrosine as an
antidote to sudden, extreme stress. Tyrosine's effect in the brain is to
increase dopamine and norepinephrine, two common brain
chemicals.
Inspired by the findings, researchers at the United States Army
Research Institute of Environmental Medicine in Natick, Mass., led
by Louis Banderet, a psychologist, tested the effects of tyrosine
supplements on soldiers under physical conditions that became
progressively harsher. The research was reported recently in the
proceedings of a NATO conference on enhancing the performance
of troops.
At the most extreme, the test conditions simulated being taken
suddenly to an elevation of about 15,500 feet, and being exposed, in
light clothing, to a temperature of 60 degrees, similar to being on a
Colorado peak on a chilly spring day. While the temperature was not
terribly uncomfortable, the sudden increase in elevation produces
hypoxia, a drop in the oxygen available to the brain. For several
hours, until the body adjusts, most people find it difficult to think
clearly under those conditions.
When there was little stress, there were few differences between the
soldiers who were given tyrosine supplements and those who were
not. But the benefits of tyrosine became increasingly evident as
conditions became harsher.
Tests showed that the soldiers who received tyrosine consumed in
pure form performed better at mental tasks that simulated, for
instance, charting coordinates on a map, translating messages into a
code and making complex decisions. The soldiers who took tyrosine
also had a significant edge in alertness and quick response.
In addition the soldiers who had taken tyrosine were in better moods;
they were less anxious or tense, and felt their thinking to be clearer
than did the others. Moreover, they suffered less from the purely
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physical rigors of the test, such as coldness, muscle discomfort and
headaches.
The combination of physical ease and mental agility under stress
produced by tyrosine, the researchers suggest, gives it a distinct
advantage over both stimulant drugs, which typically make patients
jumpy and tense, and tranquilizers, which usually reduce alertness.
One general advantage of nutrients like tyrosine over psychiatric
drugs is their potential for significantly affecting brain activity with a
minimum of undesirable side effects. Very often the nutrients have
their effect on the brain in about the same dose as a person would
consume in normal eating. However, for these nutrients be most
effective, they must typically be consumed in a pure form, rather than
as part of a normal meal.
This is because after one eats, choline and those amino acids in the
food that can affect neurotransmitters must compete with each other
for access to the limited biochemical channels that allow them to
cross from the blood into the brain. For instance both the tyrosine
and the choline in an egg vie for entry into the brain.
But if the amino acids or choline are consumed singly and in
concentration, they enter the brain in concentrated doses, and so can
have the potent, drug-like effects that psychiatrists are seeking to use
in treating mental disorders.
The one exception is the amino acid tryptophan, which increases
production in the brain of the neurotransmitter serotonin.
Tryptophan is unique among amino acids in how it is affected by
carbohydrates. Eating carbohydrates causes the body to secrete
insulin, which in turn prompts amino acids in the blood to be taken
up into muscle. Tryptophan, however, is unaffected by insulin; it
remains in the blood and is free to cross into the brain with little or
no competition.
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Studies have shown that tryptophan is the most likely reason that a
meal heavy in carbohydrates often makes people drowsy. Many of the
brain structures rich in serotonin play a role in triggering the onset of
sleep.
Research by Bonnie Spring, a psychologist at Texas Tech University
in Lubbock, has shown that carbohydrates - a plate of pasta, for
instance - tend to make women sleepy and men calmer. And most
people find their concentration wanes within an hour or two of such
a meal.
Because of its sleep-inducing effects, tryptophan has been used for
several years as a way to help insomniacs fall asleep. The pure
tryptophan works most effectively when it is taken with a highcarbohydrate snack - a piece of fruit, say, rather than a glass of hot
milk, which has protein that would compete with the tryptophan.
The Natural Cure for Depression
Some practitioners believe that most people on antidepressants could
really just use a better diet.
For those accustomed to the notion that therapy means talking
through problems and getting a prescription for antidepressants, this
may seem an unusual approach. No form of psychotherapy can be
fully effective if the brain is not functioning properly, and to do that
the brain needs optimal nourishment, something that is increasingly
hard to come by in the typical diet.
Depressed, tired, overweight people are often told they need Prozac,
when in fact all they really need to get their brains and bodies on
track is a steady supply of real food. Drink lots of water and eat
plenty of vegetables and fruits, whole grains, and lean protein.
Diets high in refined foods, sugars, and unhealthy fats can actually
interfere with the natural brain chemistry. Modern eating habits are
part of what makes many people depressed, says Dr. Michael Lesser,
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a psychiatrist in Berkeley, California, who also bases his treatment on
an evaluation of a patient's diet and lifestyle. "Ironically, though we
live in a wealthy society, our diets are deficient in crucial nutrients,"
says Dr. Lesser, author of The Brain Chemistry Plan.
Nutritional deficiencies can contribute to chemical imbalances, like
anemia and hypothyroidism, which in turn can lead to anxiety,
insomnia — and depression. People with depression are commonly
diagnosed with low levels of zinc, magnesium, B vitamins, essential
fatty acids, and amino acids. In fact, Dr. Lesser firmly believes that
most cases of depression are either caused or exacerbated by poor
nutrition.
Indeed, the last few years have seen increasing numbers of studies
finding that specific nutrients can help manage, and even reverse,
depression, along with anxiety, attention deficit hyperactivity disorder
(ADHD), schizophrenia, and even autism. One of the most
compelling, a study from Harvard, found that omega-3 fatty acids in
conjunction with medication worked so powerfully on manic
depression that the study was halted so every subject could take
them.
The new research has inspired the launch of at least one scientific
journal devoted to the subject, Nutritional Neuroscience, and dozens
of books — including Natural Highs: Feel Good All the Time and the
just-released 8 Weeks to Vibrant Health. "There have been huge
advances over the past few years finding that nutritional intervention
can treat many behavioral and mental conditions we used to think
were untreatable," says Lewis Mehl-Madrona, associate professor of
clinical psychiatry at the University of Arizona College of Medicine.
Why so much interest? Experts say nutritional therapy is catching on
in part due to growing discomfort with antidepressants: Physicians
are realizing they are not as effective long-term as was once hoped,
and they often have nasty side effects, such as loss of libido and
nausea. "We're becoming more realistic about the limitations of
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drugs," says Susan Lord, director of nutrition programs for the
Center for Mind-Body Medicine in Washington, D.C. "They're not
the magic bullets we once thought."
Much of the interest is also coming from patients themselves, says
Cass. As more people realize they need to pay attention to what they
eat in order to feel good, more are asking their doctors for nutritional
help. Lord sees this in the growing popularity of the "Food as
Medicine" workshops her center hosts for health care practitioners.
Within five years, she predicts, the demand among doctors for
education about nutrition will be huge. "Most physicians already see
the writing on the wall," she says, "and are in the uncomfortable
position of not knowing the answers, but feeling they should."
While it is clear the brain can be greatly influenced by what we eat,
researchers are just beginning to figure out why. The answer has at
least something to do with the composition of neurotransmitters,
whose intricate wiring controls thinking, actions, and moods; these
chemicals are made of amino acids, and certain vitamins and minerals
play critical roles in their formation. The very makeup of brain cells
also depends on nutrients -- omega-3s are part of every cell
membrane.
When a person's diet is deficient in some of these nutrients,
neurotransmitters are not made correctly or do not get what they
need to function properly, and various emotional and mental
disorders can result. For instance, low blood sugar can contribute to
some forms of depression, and so can low levels of zinc in some
people.
For all the recent research, Lesser and Cass are still among a
maverick few who focus primarily on nutritional interventions for
mental health problems. For most psychiatrists, drugs are better
known, despite their problematic side effects -- and therefore less
risky.
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Both Lesser and Cass arrived at the notion that nutrition can
influence brain chemistry early in their medical careers. Lesser, who
was conventionally trained at Cornell and Albert Einstein Medical
Center in New York City in the 1960s, started tinkering with
nutrients after becoming frustrated by his field's emphasis on drugs.
Shortly after he had finished his residency, Lesser came across a
report that treating schizophrenics with niacin tended to improve
their symptoms. He figured that if the niacin worked, he should also
experiment with other dietary strategies that have been linked to
mood.
So he tried the approach on a patient of his own and put the young
man on a high-protein diet, gave him a slew of supplements,
including niacin, vitamin C, and zinc, and told him to cut out caffeine
and cigarettes. Soon after his patient showed dramatic improvement,
Lesser founded the Orthomolecular Medical Society, with the stated
objective of emphasizing natural substances such as vitamins,
minerals, amino acids, and essential fats in the prevention and
treatment of diseases.
Start by evaluating the patient in a number of ways -- emotionally, physically, and
biochemically. The specific health prescriptions, should include supplements and food,
often in tandem with exercise, natural hormones, and mind-body techniques.
The approach isn't for everyone. It requires that a patient be a full partner in his or her
care, and not everyone is motivated enough to make what can amount to pretty daunting
lifestyle changes, including shopping for organic food, preparing meals without using a
lot of salt, sugar, and unhealthy fats, and taking all those supplements -- especially people
who are depressed to begin with.
Sometimes the best option is indeed medication, says Cass, particularly with severe cases
of depression. "The most important thing is to help the patient," she says.
But even small changes — like cutting out processed foods, or adding daily fish oil pills
— can make a big difference, they say. And once started, the process can develop its own
momentum. "People start eating a little better or taking a few supplements, and they often
start feeling a little better," says Lord. "That's when they become open to trying more
changes."
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Many of the patients who do manage to stick to the program say it is worth the effort.
After a couple of months on Cass's regimen, Rebecca Jones is certainly convinced. She
hasn't had to make many dietary adjustments -- she was already eating reasonably well to
begin with and exercising a few times a week. So the only change she's made was to start
taking supplements. But the results have been dramatic.
The supplements are costly, she admits, running about $100 a month. "But that's all it
takes -- I don't need any expensive prescription drugs." She expects to stay on some of
the supplements for the rest of her life, and to continue to consult with Cass periodically.
"But that's okay," she says. "My mood has evened out considerably -- all of the
depressive symptoms I had are gone. I'm much, much better now."
Alternatives to Prozac
Many experts now believe that diet and supplements can make a big difference in treating
depression, though not every type. People who can tie their sadness to a particular event,
like the breakup of a relationship or a job loss, are much more likely to find success with
mood-boosting supplements. "But if your depression is unexplained, you should be
seeing a professional and asking serious questions -- not just popping 5-HTP," says
Timothy Birdsall, director of naturopathic medicine for Cancer Treatment Centers of
America. Depression might be the result of heart trouble that doesn't allow enough
oxygen to get to the brain, for instance, or an intestinal problem that prevents efficient
absorption of vitamin B-12.
In fact, professional guidance can make any program more effective by making it more
targeted, says Mark Hyman, editor-in-chief of Alternative Therapies in Health and
Medicine. Physicians can test patients first to diagnose chemical imbalances, and then
take it from there. Working with a doctor also helps determine what does and doesn't
work. "We're not the best judge of our own condition when it comes to depression," says
Kenneth Pelletier, clinical professor of medicine at the University of Maryland School of
Medicine. "It's something you shouldn't tackle alone."
B vitamins Many people, particularly women over 65, have B-12 deficiencies and
respond dramatically to injections of the vitamin. But all B vitamins can boost mood;
they work by facilitating neurotransmitter function. Other pluses: B vitamins are critical
for preventing other maladies, including heart disease, cancer, and Alzheimer's. Dosage:
Take at least 800 micrograms of folate, 1,000 mcg of B-12, and 25 to 50 milligrams of B6. A B-complex vitamin should do the trick, says Hyman, and if you're depressed, take
more. Take them in combination because otherwise one can mask another B vitamin
deficiency. Risks: None.
Essential Fatty Acids Their benefits are among the best documented. The reason they're
so effective? Essential fatty acids are part of every cell membrane, and if those
membranes aren't functioning well, then neither is your brain. Dosage: For depression,
take at least 2,000 to 4,000 mg of fish oil a day. Should be purified or distilled so it's free
of heavy metals. Risks: Very safe, albeit unstable. Since it can oxidize in your body, take
it along with other antioxidants, like vitamin E (400 IUs a day).
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Amino acids The building blocks of neurotransmitters; 5-HTP is the most popular.
Taking it can elevate mood in cases of depression, anxiety, and panic attacks, and relieve
insomnia. Increases production of the neurotransmitter serotonin. Dosage: Start with a
low dose, 50 mg two to three times a day; after two weeks, increase the dose to 100 mg
three times a day. Risks: Mild nausea or diarrhea. Before starting, get off antidepressants
(under a doctor's supervision); the combination can produce an overload of serotonin.
Saint-John's-wort One of the best-known remedies. Best for mild to moderate
depression. Dosage: Start on a dose of 300 mg (standardized to 0.3 percent hypericin
extract) two to three times a day, depending on severity of depression; it can take three
weeks to show benefits. Risks: It may interfere with up to half of all drugs, prescription
and over-the-counter.
SAM-e An amino acid combination produced by humans, animals, and plants.
Supplements come from a synthetic version produced in a lab that has shown a lot of
promise in European studies. May affect the synthesis of neurotransmitters. Has fewer
side effects than 5-HTP and fewer drug interactions than Saint-John's-wort. Dosage: Can
range from 400 to 1,200 mg a day, though high doses can cause jitteriness and insomnia.
Risks: People with bipolar disorder shouldn't use it without supervision because it can
trigger mania.
Rhodiola rosea Considered an adaptogen, which means it can increase your resistance to
a variety of stressors. May be good for mild to moderately depressed patients. Dosage:
Take 100 to 200 mg three times a day, standardized to 3 percent rosavin. Risks: More
than 1,500 mg a day can cause irritability or insomnia.
DHEA This hormone is marketed in Europe specifically for postmenopausal depression,
though it may be helpful for other forms as well. Has been used in conjunction with
estrogen to treat hot flashes. Not clear why it helps boost mood and energy. Dosage: 25
to 200 mg a day. Risks: Any hormonal supplement has the potential to increase cancer
risk.
Finding professional help. To find an integrative doctor, visit drweilselfhealing.com and
click integrative medicine clinics; or check holisticmedicine.org/public/public.shtml. For
an orthomolecular physician, visit orthomed.org and alternativementalhealth.com, which
is also an excellent source of information about natural alternatives to medication.
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