Nutrition
and Mental Wellness
by
Kim Schoenhals
Different
than cognitive function, which involves memory, concentration and reasoning skills,
mental wellness involves emotional health, including depression, anxiety and stress.
Depression is a group of disorders affecting approximately 9.5 percent of the
population--18.8 million Americans--in any one-year period, according to the National
Institute of Mental Health (NIMH), a division of the National Institutes of Health
(NIH). And, 35 million to 40 million Americans will suffer from a depressive disorder
at some point in their lives.
Anxiety disorders are also a potentially
crippling category that includes generalized anxiety disorder, panic disorder,
obsessive-compulsive disorder, post-traumatic stress disorder and phobias (including
social phobia, also known as social anxiety disorder), according to the Anxiety
Disorders Association of America (ADAA). Anxiety disorders are the most common
mental illness in the United States, according to ADAA, affecting 13.3 percent
(19.1 million) of the U.S. adult population.
Consumers who suffer from
mental issues are often more likely than the general population to take supplements,
according to research from the Natural Marketing Institute's (NMI) Health &
Wellness Trends Database, three years of trended data including more than 2,000
consumer household respondents. NMI reported that 28.3 percent of the general
population reported managing or treating stress, 14.9 percent depression and 10.6
percent overall mood.
Nutrition is an important factor in maintaining
mental wellness, and symptoms of depression can sometimes be attributed to various
nutrient deficiencies. And, depression and anxiety disorders are often associated
with unhealthy eating practices, according to researchers from the Fred Hutchinson
Cancer Research Center in Seattle. Their research indicated that psychologically
distressed individuals are more than twice as likely to have unhealthy eating
practices, with stressed women consuming fewer fruits and vegetables and stressed
men consuming more fat than their healthy counterparts.1
Some nutrients
that play major roles in mental wellness are essential fatty acids, vitamins and
minerals. In addition, there are numerous botanical ingredients that can improve
mood and reduce anxiety, and there are many compounds that naturally occur in
the body and can be taken as supplements to promote chemical balance for improved
mental health. In combination with a healthy diet and exercise regimen, these
ingredients can contribute to enhanced mental wellness and may dissipate symptoms
of depression and anxiety.
Fats and Oils
Omega-3
fatty acids have been rising in popularity for enhancing mental health--5.4 percent
of the general population reports supplementing with omega-3 fatty acids, according
to NMI. In comparison, 12.2 percent of consumers who are treating mood, 8 percent
of those treating stress and 9.5 percent of those treating depression take omega-3
supplements.
Of the omega-3 fatty acids, eicosapentaenoic acid (EPA)
and docosahexanoic acid (DHA) have been studied in particular for their link with
mental wellness. Researchers at Hammersmith Hospital in London reported a case
study in which EPA improved symptoms of depression when combined with traditional
antidepressant therapy. After one month of adjuvant EPA treatment, researchers
noted a "dramatic and sustained" improvement in all symptoms of depression,
including suicidal tendencies and social phobia.2
Similar results were found
by researchers at Ben Gurion University of the Negev in Beer-Sheva, Israel. They
studied 20 severely depressed patients who, for four weeks, were randomly assigned
in a double blind fashion to receive either the ethyl ester of EPA or placebo
in addition to their usual medications. After three weeks, researchers reported
highly significant benefits in the omega-3 group compared to placebo.3
A supplemental combination of EPA and DHA was shown by researchers at Harvard
Medical School to improve symptoms of manic depression. Researchers conducted
a nine-month, double blind trial comparing treatment with 9.6 g/d of marine omega-3
fatty acids to placebo in 30 patients with unstable bipolar disease. Results demonstrated
that 64 percent of patients receiving EPA/DHA improved, while only 19 percent
of the placebo group did.4
Independently,
DHA possesses its own correlation with mental wellness. Researchers from Massachusetts
General Hospital and Harvard Medical School in Boston conducted a research review
of DHA in depression and noted that geographic areas with high DHA consumption
exhibited decreased rates of depression. From this research, the study's authors
noted the role of DHA as therapy for minor depression should be considered.5
Krill oil, also suspected to have some mood-enhancing properties, contains
an "excellent" omega-3-to-omega-6 ratio, according to Michael A. Schmidt,
author of Brain-Building Nutrition (Frog Ltd., 2001). Krill oil (as Neptune™
Krill Oil, the exclusive agent for which is CPB International Inc. in Newfoundland,
N.J.) contains roughly 44 percent omega-3 fatty acids, according to Schmidt, including
19.2 percent EPA, 14.1 percent DHA and 15.2 percent linoleic acid. According to
CPB International, Neptune Krill Oil is currently being studied in several clinical
applications.
Another oil suspected to have antidepressant properties
is that taken from Perilla frutescens, a member of the mint family. Researchers
from Tokyo Medical University administered a water extract of perilla (Britton
var. acuta Kudo, Perillae Herba) to mice who were studied in a forced swimming
test. They determined, by feeding mice different strengths of perilla, that it
is the rosmarinic acid found in perilla that possesses antidepressive activity.6
Additional animal research conducted at Nanjing University in China indicated
that a Chinese formula that contained Perilla frutescens possessed an antidepressant
activity close to that of Prozac.7
Botanicals
While EFAs and other oils have gained positive attention in the past few years,
herbal ingredients have received some bad press in recent times. St. John's wort
(Hypericum perforatum) is arguably one of the most notorious herbs used in the
realm of mental health. However, those consumers seeking to enhance mood or manage
stress are more likely to take the herb than the general population, according
to data from NMI--while 6.9 percent of the general population cited taking St.
John's wort, 19.7 percent of those treating mood, 12.3 percent of those treating
stress and 15.9 percent of those treating depression cited taking St. John's wort.
Because of the pathway along which it is absorbed by the body--known
as the cytochrome P450 (CYP3A4) pathway--St. John's wort has been found to speed
up the metabolism of several classes of medications, including transplant medication,8,
9 the AIDS medication indinavir,10 birth control11 and the cancer drug irinotecan.12
In addition to the numerous contraindications now noted for St. John's
wort, the herb was recently criticized when a large trial funded by NIH was published
in April, deeming St. John's wort no more effective than placebo for treating
severe depression. However, the trial also found the mood-enhancing drug sertraline
(Zoloft®, by Pfizer) was ineffective.13
As a mood-lifting herb,
St. John's wort has demonstrated similar benefits for depression as prescription
medicine. German researchers conducted a randomized, double blind, parallel trial
with 324 outpatients with mild to moderate depression who were assigned to receive
either 75 mg of imipramine twice daily or 250 mg of St. John's wort extract (ZE
117) twice daily for six weeks. Researchers concluded that St. John's wort was
therapeutically equivalent to imipramine, although the herb was better tolerated.14
Similarly, a double blind, randomized trial involving 87 men and women with severe
depression, conducted by researchers out of St. Mary's Hospital Centre in Montreal,
indicated St. John's wort (900 mg/d to 1,800 mg/d) was superior to sertraline
(50 mg/d to 100 mg/d) for severe depression because of its comparatively "benign"
side effects.15
Another herb that has gained a reputation in the media
lately is kava (Piper methysticum). A collection of adverse event reports (AERs)
linking kava with possible liver damage surfaced in Germany last November, after
which a coalition of industry groups commissioned a scientific review of the AERs,
which was released in February. Donald Waller, Ph.D., a board-certified toxicologist
and professor at the University of Illinois in Chicago, reviewed more than 50
AERs from the United States and Germany and concluded that there was "no
clear evidence that the liver damage reported in the United States and Europe
was caused by the consumption of kava." And, those cases in which there was
a possible association between kava extract and liver damage "appear to have
been hypersensitivity or idiosyncractic base responses," Waller added.
In late March, the Food and Drug Administration (FDA) released a consumer
advisory for kava-containing supplements, linking the herb to liver toxicity.
Most recently, on June 14, the German health authorities (as BfArM) informed all
German manufacturers of kava-containing products that their registrations had
been cancelled.
Despite the controversy, kava is still a fairly popular
herbal supplement among American consumers. NMI noted that 3.1 percent of the
general population takes kava supplements, while 10.4 percent of those treating
mood, 6 percent of those treating stress and 7.9 percent of those treating depression
take the herb.
Contrary to the AERs that have surfaced in the past year,
kava was found by researchers at the University of Exeter in Devon, England, to
generally be safe. They reviewed clinical evidence relating to the safety of kava
extracts and found adverse events are generally rare, mild and reversible.16
Kava has also been found helpful for reducing anxiety and stress. A pilot study
out of London's Psychopharmacology Research Group indicated kava and valerian
can relieve stress-related insomnia. Research involved 24 patients suffering from
stress-induced insomnia who were treated for six weeks with 120 mg/d of kava,
followed by a two-week washout period, and then the remaining 19 subjects received
600 mg/d of valerian for another six weeks. Subjects reported that both herbs
relieved total stress severity and insomnia, with no major differences reported
between the two.17
A Cochrane Review conducted by researchers at the
University of Exeter in Devon, England, garnered similar results. Researchers
conducted a meta-analysis of kava research and included seven randomized, double
blind trials on the herb as used to treat anxiety. They concluded that all of
the reviewed trials suggested kava extract was superior to placebo, and adverse
events reported in the reviewed trials were mild, transient and infrequent.18
Ginkgo biloba is another herb suggested for improving mood disorders,
although it, too, has had some bad press recently. Two case reports out of Sir
Charles Gairdner Hospital in Perth, Western Australia, indicated ginkgo may be
linked to epileptic seizures in elderly patients. Researchers noted that the patients
(aged 78 and 84) discontinued therapy with ginkgo and were seizure-free several
months later.19
Ginkgo, however, has been found beneficial for its role
in improving mental wellness. In a research review of herbal medicines for psychiatric
disorders, researchers from the Martin Luther King Jr.-Drew Medical Center in
Los Angeles uncovered 40 controlled trials of ginkgo extracts, in which all but
one demonstrated improvement in depressed mood, anxiety and fatigue, in addition
to memory loss and concentration.20
Ginkgo may also be effective for
reducing anxiety, according to animal research conducted at the University of
Southern Mississippi in Hattiesburg. Researchers administered a standardized ginkgo
extract (100 mg/kg/d) to male mice for up to 82 consecutive days. The supplemented
mice exhibited a decrease in the anxiety seen in animals after cold water exposure,
leading the researchers to believe ginkgo extract may serve as an anti-stress
buffer.21
Another botanical that may have application in the realm of
mental wellness is lavender. According to Herbal Medicine: Expanded Commission
E Monographs (Integrative Medicine Communications, 2000), lavender (Lavandula
angustifolia) has been approved by the Commission E for internal use for restlessness
and insomnia, as well as for nervous stomach irritations and lack of appetite.
Research out of the University of Miami School of Medicine indicated that lavender
aromatherapy reduced depressed mood and increased relaxation among a group of
40 subjects who were completing math problems.22
The same researchers found
that when subjects were treated with rosemary aromatherapy, they demonstrated
increased alertness and reduced anxiety. Rosemary leaf was also included in the
Expanded Commission E Monographs--while the botanical is used primarily for stomach
and digestive troubles, it has been used in traditional European medicine for
alleviating nervous tension.
Used in Traditional Chinese Medicine, Magnolia
officinalis and Phellodendron amurense are thought to be synergistically helpful
for easing stress, anxiety, irritability, tension and frustration. In animal research,
the combination of botanicals (as Relora™, a patent-pending ingredient from
Next Pharmaceuticals in Irvine, Calif., the U.S. representative of which is Stauber
Performance Ingredients, based in Fullerton, Calif.) was shown to be an effective,
non-sedating anxiolytic (relives anxiety) in a common stress test.23
Usage by Consumer Segments: Those Treating Depression, Stress and Mood vs. GP
Source: The Health and Wellness Trends Database
The Natural Narketing Institute,
2002
According to an unpublished, open human trial, Relora was deemed safe,
effective and rapidly acting, and it was found to be easy on the stomach in 94
percent of the study population. Of 50 subjects who were treated with the botanical
combination for two weeks (generally taking less than the recommended dose of
200 mg three times daily), 82 percent reported that it controlled occasional mild
anxiety or depression.
Vinpocetine--a derivative of the alkaloid vincamine,
which is found in the aerial part of Vinca minor, a periwinkle--is also thought
to have application in mental wellness. Vinpocetine is commonly used to improve
memory and enhance concentration, according to literature from Locarno, Switzerland-based
Linnea. Vinpocetine has also been indicated for improving conditions that occur
as a result of insufficient blood flow to the brain, including mood changes and
depression.
Early experiments with vinpocetine indicated five main pharmacological
and biochemical actions, including enhanced brain circulation and oxygen utilization.
It has also been suggested the extract's antioxidant properties are the mechanism
behind its neuroprotective effects.
Vitamins and Minerals
In the realm of vitamins, the B vitamins have been the subject of a number of
studies involving depression and anxiety. In fact, B vitamin deficiencies can
sometimes mimic depressive symptoms. For example, levels of folic acid are usually
low in depressed individuals, and supplementation with folic acid has been linked
to improving response to antidepressant medication. Researchers from West Park
Hospital in Epsom, England, studied this correlation in 127 patients who were
taking 20 mg/d of fluoxetine and were randomized to receive either 500 mcg/d of
folic acid or a placebo. Researchers noted a significantly greater improvement
in the fluoxetine plus folic acid group, although more so in the women than the
men--93.9 percent of the women who received folic acid demonstrated a positive
response as compared to 61.1 percent of the women who received placebo.24
Levels of cobalamin (vitamin B12) have also been linked to depression and
mood disorders. Researchers at Duke University Medical Center in Durham, N.C.,
found that of 159 bereaved men, 24 percent were either overtly or marginally cobalamin
deficient, and cobalamin level was inversely related to self-reported overall
distress level, depression, anxiety and confusion.25
Elderly patients
demonstrating cobalamin deficiency are two times more likely to be severely depressed
than non-deficient patients, according to researchers from the National Institute
on Aging in Bethesda, Md., who conducted a study of 700 community-based, non-demented
women (aged 65 years and older). Researchers noted that a significant vitamin
B12 deficiency was present in 14.9 percent of the 478 non-depressed subjects,
17 percent of the 100 mildly depressed subjects and 27 percent of the 122 severely
depressed patients.26
Pyridoxine (vitamin B6) is also thought to be
involved in mental wellness because it helps convert the essential amino acid
tryptophan into serotonin, which is a neurotransmitter considered relevant to
the pathophysiology of depression. Pyridoxine supplementation may be able to improve
a depressed patient's response to medication. Researchers from Rabin Medical Center
in Petah Tikva, Israel, studied nine schizophrenic patients with minor depressive
symptoms and found that with adjuvant pyridoxine (150 mg/d) treatment for four
weeks, additional improvements in mood were achieved.27
However, a subsequent
study conducted by researchers at Ben-Gurion University of the Negev in Be'er-Sheva,
Israel, failed to reproduce these results. Researchers randomly supplemented 15
schizophrenic patients with placebo or vitamin B6 starting at 100 mg/d in the
first week and increasing by 100 mg increments to 400 mg/d in the fourth week.
After nine weeks, researchers did not note a difference between treatment or placebo
groups in terms of mental health.28
Aside from vitamins, minerals may
also play a role in mental wellness. Studies have indicated that selenium deficiency
may be linked to adverse mood states.29 A research review published last year
indicated that selenium may affect psychological condition because of its role
in thyroid function, changes in which can affect mood, behavior and cognitive
function. It was suggested that patients who have a combination of depression,
hypothyroidism and increased susceptibility to viral infections could reasonably
be assessed for selenium deficiency.30
Chromium is another mineral that
may have a role in mental health. When a patient reported a "dramatic response"
after adding chromium to sertraline therapy for dysthymic disorder (a depressed
feeling for the majority of the time for at least two years), researchers from
the University of North Carolina School of Medicine in Chapel Hill conducted a
single blind, open-label trial combining chromium picolinate and chromium polynicotinate
with traditional therapy to treat dysthymic disorder. In a series of five patients,
chromium supplementation led to remission of dysthymic symptoms. Researchers concluded
that chromium may increase response to antidepressant therapy for dysthymic disorder,
although they noted that controlled studies are needed to test the validity of
these initial observations.31
The same researchers conducted a single
blind trial with eight subjects who had refractory mood disorders and were given
chromium monotherapy. Researchers reported that in several instances, there was
a response to chromium, and side effects were rare and mild. Researchers concluded
that the antidepressant benefit of chromium could have been due to an enhancement
of insulin utilization and related increases in tryptophan availability, or by
chromium's effects on norepinephrine release.32
Compounds Present
in the Human Body
Aside from external compounds and those derived
most prevalently from the diet such as botanicals, vitamins and minerals, there
are additional compounds that naturally occur within the body that play an important
role in mental health. Hormones and phospholipids are some of these.
Melatonin--a hormone that regulates the human sleep-wake cycle, known as circadian
rhythm--seems to be linked to mood states. "Melatonin profiles are a diagnostic
tool to distinguish between several forms of depression," noted researchers
from the University Hospital in Essen, Germany. They added that in patients with
major depression, successful treatment with antidepressants correlated with an
increase in melatonin profiles, and in women with bulimia or neuralgia in addition
to fibromyalgia, melatonin replacement reduced pain, sleeping disorders and depression.33
However, researchers from the Federal University of Sao Paulo in Brazil
determined that in six healthy, male volunteers, a single low dose of melatonin
did not alter subjective sleepiness or mood. However, it did tend to improve sleep
efficiency and reduce intermittent wakefulness.34
Usage by General Population
of Supplements Related to Mental Wellness/Acuity
Source: The Health and Wellness
Trends Database
The Natural Narketing Institute, 2002
Another hormone
thought to affect mood, DHEA (dehydroepiandrosterone) is a steroid hormone produced
by the adrenal glands. A research review by investigators at the University of
British Colombia in Vancouver suggested DHEA may be therapeutically useful for
improving psychological well-being in the elderly and improving mood in clinically
depressed patients.35
However, a double blind, crossover study conducted
by researchers at the University Hospital Wurzburg in Germany indicated that four
months of supplementation with DHEA did not induce an obvious benefit in healthy
male subjects with a physiological decline of DHEA production.36 A similar conclusion
was given by researchers at Addenbrooke's Hospital in Cambridge, England, who
involved 46 men (aged 62 to 76) who received 50 mg/d of DHEA for 13 weeks in a
randomized, double blind, crossover fashion. However, the researchers also noted
that higher evening DHEA levels were associated with lower anxiety and a lower
negative mood in the morning.37
5-HTP (5-hydroxytryptophan)--the immediate
precursor of the neurotransmitter serotonin--and the essential amino acid tryptophan--which
is converted to 5-HTP and then to serotonin--are both thought to play a role in
mental wellness. In terms of mood, 5-HTP and tryptophan have been studied for
their effects in alleviating depression. A Cochrane Database Review turned up
108 randomized trials using the substances, although researchers determined that
only two trials, involving a total of 64 patients, were of sufficient quality
to meet their inclusion criteria. Researchers concluded that both 5-HTP and tryptophan
were more effective than placebo for alleviating depression, although the evidence
was not of sufficient quality to be conclusive.38
Another research review
out of the Lawrence Berkeley National Laboratory in California stated, "While
there is evidence that precursor loading may be of therapeutic value [for treating
depression], particularly for 5-HTP and tryptophan, more studies of suitable design
and size might lead to more conclusive results. However, the evidence suggests
neurotransmitter precursors can be helpful in patients with mild or moderate depression."39
Another naturally occurring agent, SAM-e (S-adenosyl-methionine) is
moderately popular as a supplement for mental wellness issues. According to NMI,
1.5 percent of the general population takes SAM-e, as compared to 4.2 percent
of those treating mood, 1.9 percent of those treating stress and 4.6 percent of
those treating depression.
SAM-e is a metabolite of the essential amino
acid methionine. It is a cofactor in three important biochemical pathways and
consequently, SAM-e is synthesized in cells throughout the body. SAM-e appears
to raise levels of dopamine, an important neurotransmitter in mood regulation,
and higher SAM-e levels in the brain are associated with successful drug treatment
of depression.
For this reason, researchers at Harvard Medical School
in late June announced plans to begin a trial to study the combined effects of
several antidepressants with SAM-e. The eight-week, open trial will be conducted
at Massachusetts General Hospital. Jonathan Alpert, M.D., Ph.D., the study's principal
investigator, noted that while there is significant evidence SAM-e is effective
as a monotherapy for depression, combination therapy should only be tried under
medical supervision, and antidepressants, including SAM-e, may exacerbate the
symptoms of bipolar disorder (manic depression). [For more on this story click
here]
A research review published this year noted that recent clinical
studies have revealed SAM-e as a safe and effective treatment for mild to moderate
depression, although further research is required to clarify SAM-e's role as a
potential first line treatment for depression.40
Phosphatidylserine (PS),
a phospholipid found in high concentrations in the brain, affects the levels of
neurotransmitters related to mood. In the late 1980s, researchers at the University
of Rome reported 300 mg/d of soy-derived PS (as Leci-PS® from Champaign, Ill.-based
Degussa Bioactives) helped restore a mechanism that suppresses the production
of cortisol and other adrenal steroid hormones linked to the stress response.41
Recent research demonstrated that PS also affected the subjective feelings
of stress. Researchers at the University of Wales Swansea in England investigated
the effects of soy-derived PS on 48 healthy young men (average age of 20.8 years)
who were asked to perform a stressful mental arithmetic task. Researchers noted
that after supplementation with 300 mg/d of PS for one month, subjects reported
being in a better mood and feeling less stressed.42
Millions of Americans
are suffering from some form of emotional illness, whether in the form of a depressive
disorder or an anxiety disorder. While there is generally no "cure"
for these disorders, help is available in the form of pharmaceuticals, and supplements
can offer adjuvant or singular support in many cases, according to current research.
From botanicals to naturally occurring compounds, and from vitamins and minerals
to essential fatty acids, consumers and manufacturers alike have a variety of
options from which to choose for good mental health.
Editor's notes:
Some content for this story provided by Intramedicine (www.intramedicine.com).