Low vitamin D levels and depression linked in young women
A new study from Oregon State University suggests there is a
relationship between low levels of vitamin D and depression in otherwise
healthy young women.
OSU researchers found that young women with lower levels of
vitamin D were more likely to have clinically significant depressive symptoms
over the course of a five-week study, lead author David Kerr said. The results
were consistent even when researchers took into account other possible
explanations, such as time of year, exercise and time spent outside.
"Depression has multiple, powerful causes and if vitamin D
is part of the picture, it is just a small part," said Kerr, an associate
professor in the School of Psychological Science at OSU. "But given how
many people are affected by depression, any little inroad we can find could
have an important impact on public health."
The findings were published March 2015 in the journal Psychiatry
Research. Co-authors are Sarina Saturn of the School of Psychological
Science; Balz Frei and Adrian Gombart of OSU's Linus Pauling Institute; David
Zava of ZRT Laboratory and Walter Piper, a former OSU student now at New York
University.
Vitamin D is an essential nutrient for bone health and muscle
function. Deficiency has been associated with impaired immune function, some
forms of cancer and cardiovascular disease, said Gombart, an associate
professor of biochemistry and biophysics, principal investigator with the Linus
Pauling Institute and international expert on vitamin D and the immune
response.
People create their own vitamin D when their skin is exposed to
sunlight. When sun is scarce in the winter, people can take a supplement, but
vitamin D also is found in some foods, including milk that is fortified with
it, Gombart said. The recommended daily allowance of vitamin D is 600 IU per
day. There is no established level of vitamin D sufficiency for mental health.
The new study was prompted in part because there is a widely
held belief that vitamin D and depression are connected, but there is not
actually much scientific research out there to support the belief, Kerr said.
"I think people hear that vitamin D and depression can
change with the seasons, so it is natural for them to assume the two are
connected," he said.
According to Kerr and his colleagues, a lot of past research has
actually found no association between the two, but much of that research has
been based on much older adults or special medical populations.
Kerr's study focused on young women in the Pacific Northwest
because they are at risk of both depression and vitamin D insufficiency. Past
research found that 25 percent of American women experience clinical depression
at some point in their lives, compared to 16 percent of men, for example.
OSU researchers recruited 185 college students, all women ages
18-25, to participate in the study at different times during the school year.
Vitamin D levels were measured from blood samples and participants completed a
depression symptom survey each week for five weeks.
Many women in the study had vitamin D levels considered
insufficient for good health, and the rates were much higher among women of
color, with 61 percent of women of color recording insufficient levels,
compared to 35 percent of other women. In addition, more than a third of the
participants reported clinically significant depressive symptoms each week over
the course of the study.
"It may surprise people that so many apparently healthy
young women are experiencing these health risks," Kerr said.
As expected, the women's vitamin D levels depended on the time
of year, with levels dropping during the fall, at their lowest in winter, and
rising in the spring. Depression did not show as a clear pattern, prompting
Kerr to conclude that links between vitamin D deficiency and seasonal
depression should be studied in larger groups of at-risk individuals.
Researchers say the study does not conclusively show that low
vitamin D levels cause depression. A clinical trial examining whether vitamin D
supplements might help prevent or relieve depression is the logical next step
to understanding the link between the two, Kerr said.
OSU researchers already have begun a follow-up study on vitamin
D deficiency in women of color. In the meantime, researchers encourage those at
risk of vitamin D deficiency to speak with their doctor about taking a
supplement.
"Vitamin D supplements are inexpensive and readily
available." Kerr said. "They certainly shouldn't be considered as
alternatives to the treatments known to be effective for depression, but they
are good for overall health."
Low
vitamin D levels linked to depression
Low levels of vitamin D have been linked
to depression, according to UT Southwestern Medical Center psychiatrists
working with the Cooper Center Longitudinal Study. It is believed to be the
largest such investigation ever undertaken.
Low levels of vitamin D already are
associated with a cavalcade of health woes from cardiovascular diseases to
neurological ailments. This new study – published in Mayo Clinic Proceedings –
helps clarify a debate that erupted after smaller studies produced conflicting
results about the relationship between vitamin D and depression. Major
depressive disorder affects nearly one in 10 adults in the U.S.
"Our findings suggest that screening
for vitamin D levels in depressed patients – and perhaps screening for
depression in people with low vitamin D levels – might be useful," said
Dr. E. Sherwood Brown, professor of psychiatry and senior author of the study,
done in conjunction with The Cooper Institute in Dallas. "But we don't
have enough information yet to recommend going out and taking
supplements."
UT Southwestern researchers examined the
results of almost 12,600 participants from late 2006 to late 2010. Dr. Brown
and colleagues from The Cooper Institute found that higher vitamin D levels
were associated with a significantly decreased risk of current depression,
particularly among people with a prior history of depression. Low vitamin D
levels were associated with depressive symptoms, particularly those with a
history of depression, so primary care patients with a history of depression
may be an important target for assessing vitamin D levels. The study did not
address whether increasing vitamin D levels reduced depressive symptoms.
The scientists have not determined the
exact relationship – whether low vitamin D contributes to symptoms of
depression, whether depression itself contributes to lower vitamin D levels, or
chemically how that happens. But vitamin D may affect neurotransmitters,
inflammatory markers and other factors, which could help explain the
relationship with depression, said Dr. Brown, who leads the
psychoneuroendocrine research program at UT Southwestern.
Vitamin D levels are now commonly tested
during routine physical exams, and they already are accepted as risk factors
for a number of other medical problems: autoimmune diseases; heart and vascular
disease; infectious diseases; osteoporosis; obesity; diabetes; certain cancers;
and neurological disorders such as Alzheimer's and Parkinson's diseases,
multiple sclerosis, and general cognitive decline.
Investigators used information gathered
by the institute, which has 40 years of data on runners and other fit
volunteers. UT Southwestern has a partnership with the institute, a preventive
medicine research and educational nonprofit located at the Cooper Aerobics
Center, to develop a joint scientific medical research program aimed at
improving health and preventing a wide range of chronic diseases. The institute
maintains one of the world's most extensive databases – known as the Cooper
Center Longitudinal Study – that includes detailed information from more than
250,000 clinic visits that has been collected since Dr. Kenneth Cooper founded
the institute and clinic in 1970.
Treating vitamin D deficiency may improve depression
Women with moderate to severe depression
had substantial improvement in their symptoms of depression after they received
treatment for their vitamin D deficiency, a new study finds. The case report
series was presented at The Endocrine Society's 94th Annual Meeting (2012) in
Houston.
Because the women did not change their
antidepressant medications or other environmental factors that relate to
depression, the authors concluded that correction of the patients' underlying
shortage of vitamin D might be responsible for the beneficial effect on
depression.
"Vitamin D may have an
as-yet-unproven effect on mood, and its deficiency may exacerbate
depression," said Sonal Pathak, MD, an endocrinologist at Bayhealth
Medical Center in Dover, Del. "If this association is confirmed, it may
improve how we treat depression."
Pathak presented the research findings in
three women, who ranged in age from 42 to 66. All had previously diagnosed
major depressive disorder, also called clinical depression, and were receiving
antidepressant therapy. The patients also were being treated for either Type 2
diabetes or an underactive thyroid (hypothyroidism).
Because the women had risk factors for
vitamin D deficiency, such as low vitamin D intake and poor sun exposure, they
each underwent a 25-hydroxyvitamin D blood test. For all three women, the test
found low levels of vitamin D, ranging from 8.9 to 14.5 nanograms per
milliliter (ng/mL), Pathak reported. Levels below 21 ng/mL are considered
vitamin D deficiency, and normal vitamin D levels are above 30 ng/mL, according
to The Endocrine Society.
Over eight to 12 weeks, oral vitamin D
replacement therapy restored the women's vitamin D status to normal. Their
levels after treatment ranged from 32 to 38 ng/mL according to the study
abstract.
After treatment, all three women reported
significant improvement in their depression, as found using the Beck Depression
Inventory. This 21-item questionnaire scores the severity of sadness and other
symptoms of depression. A score of 0 to 9 indicates minimal depression; 10 to
18, mild depression; 19 to 29, moderate depression; and 30 to 63, severe
depression.
One woman's depression score improved
from 32 before vitamin D therapy to 12, a change from severe to mild
depression. Another woman's score fell from 26 to 8, indicating she now had
minimal symptoms of depression. The third patient's score of 21 improved after
vitamin D treatment to 16, also in the mild range.
Other studies have suggested that vitamin
D has an effect on mood and depression, but there is a need for large,
good-quality, randomized controlled clinical trials to prove whether there is a
real causal relationship, Dr Pathak said.
"Screening at-risk depressed
patients for vitamin D deficiency and treating it appropriately may be an easy
and cost-effective adjunct to mainstream therapies for depression," she
said.
Vitamin
D deficiency, depression linked
Vitamin D deficiency is not just harmful to physical
health—it also might impact mental health, according to a team of researchers
that has found a link between seasonal affective disorder, or SAD, and a lack
of sunlight.
"Rather than being one of many factors, vitamin D could
have a regulative role in the development of SAD," said Alan Stewart of
the University of Georgia College of Education.
An international research partnership between UGA, the
University of Pittsburgh and the Queensland University of Technology in
Australia reported the finding in the November 2014 issue of the journal
Medical Hypotheses.
Stewart and Michael Kimlin from QUT's School of Public
Health and Social Work conducted a review of more than 100 leading articles and
found a relationship between vitamin D and seasonal depression.
"Seasonal affective disorder is believed to affect up
to 10 percent of the population, depending upon geographical location, and is a
type of depression related to changes in season," said Stewart, an
associate professor in the department of counseling and human development
services.
"People with SAD have the same symptoms every year,
starting in fall and continuing through the winter months."
Stewart said, based on the team's investigations, vitamin D
was likely to be a contributing factor in seasonal depression.
"We believe there are several reasons for this,
including that vitamin D levels fluctuate in the body seasonally, in direct
relation to seasonally available sunlight," he said. "For example,
studies show there is a lag of about eight weeks between the peak in intensity
of ultraviolet radiation and the onset of SAD, and this correlates with the
time it takes for UV radiation to be processed by the body into vitamin D.
Vitamin D is also involved in the synthesis of serotonin and
dopamine within the brain, both chemicals linked to depression, according to
the researchers.
"Evidence exists that low levels of dopamine and
serotonin are linked to depression, therefore it is logical that there may be a
relationship between low levels of vitamin D and depressive symptoms,"
said Kimlin, a Cancer Council Queensland Professor of Cancer Prevention
Research.
"Studies have also found depressed patients commonly
had lower levels of vitamin D."
Vitamin D levels varied according to the pigmentation of the
skin. People with dark skin often record lower levels of vitamin D, according
to the researchers.
"Therefore it is suggested that persons with greater
skin pigmentation may experience not only higher risks of vitamin D deficiency,
but also be at greater risk of psychological and psychiatric conditions,"
he said.
Kimlin, who heads QUT's National Health and Medical Research
Council Centre for Research Excellence in Sun and Health, said adequate levels
of vitamin D were essential in maintaining bone health, with deficiency causing
osteomalacia in adults and rickets in children. Vitamin D levels of more than
50 nanomoles per liter are recommended by the U.S. Institute of Medicine.
"What we know now is that there are strong indications
that maintaining adequate levels of vitamin D are also important for good
mental health," Kimlin said. "A few minutes of sunlight exposure each
day should be enough for most people to maintain an adequate vitamin D
status."
"Queensland is known as the Sunshine State in Australia
but that doesn't mean all Queenslanders get enough vitamin D," Kimlin
said. "This research is of international importance because no matter
where you live, low levels of vitamin D can be a health concern."
Vitamin D lifts mood during cold weather months
A daily dose of vitamin D lifts mood
during cold weather months when days are short and more time is spent indoors.
“Vitamin D deficiency continues to be a
problem despite the nutrient’s widely reported health benefits,” said Sue
Penckofer, PhD, RN, professor, MNSON. “Chicago winters compound this issue when
more people spend time away from sunlight, which is a natural source of vitamin
D.”
Diet alone may not be sufficient to manage
vitamin D levels. A combination of adequate dietary intake of vitamin D,
exposure to sunlight, and treatment with vitamin D2 or D3 supplements can
decrease the risk of certain health concerns. The preferred range in the body
is 30 - 60 ng/mL of 25(OH) vitamin D.
Loyola faculty members plan to take
vitamin D research a step further by evaluating whether weekly vitamin D
supplements improve blood sugar control and mood in women with diabetes.
Depression is associated with increased insulin resistance, so people with
diabetes have a greater risk for the disease than those without depression.
Women also tend to have greater rates of depression and poorer blood sugar
control than men with diabetes.
“There is evidence to suggest that
vitamin D supplementation may decrease insulin resistance,” said Dr. Penckofer.
“If we can stabilize insulin levels, we may be able to simply and cost
effectively improve blood sugar control and reduce symptoms of depression for
these women.”
Loyola is currently enrolling women in
this clinical trial. In order to enter the study, they must be 18 to 70 years
of age, have stable type 2 diabetes, signs of depression and no other major
medical illness. Eighty women with type 2 diabetes and signs of depression will
be given a weekly dose of vitamin D (50,000 IU) for a period of six months.
Study participants will be evaluated at three points during this time.
"Vitamin D has widespread benefits
for our health and certain chronic diseases in particular," Dr. Penckofer
said. "Our research may shed greater light on the role this nutrient plays
in managing two conditions that impact millions of Americans. If proven to be
successful, vitamin D may an important addition to care for diabetes and
depression."
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