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Background: Vegetarian diets are associate with cardiovascular and other health benefits, but little is known about mental health benefits or risks. Aims: To determine whether self-identification of vegetarian dietary habits is associated with significant depressive symptoms in men. Method: Self-report data from 9668 adult male partners of pregnant women in the Avon Longitudinal Study of Parents and Children (ALSPAC) included identification as vegetarian or vegan, dietary frequency data and the Edinburgh Post Natal Depression Scale (EPDS). Continuous and binary outcomes were assessed using multiple linear and logistic regression taking account of potential confounding variables including: age, marital status, employment status, housing tenure, number of children in the household, religion, family history of depression previous childhood psychiatric contact, cigarette and alcohol consumption. Results: Vegetarians [n = 350 (3.6% of sample)], had higher depression scores on average than non-vegetarians (mean difference 0.96 points [95%CI + 0.53, + 1.40]) and a greater risk for EPDS scores above 10 (adjusted OR = 1.67 [95% CI: 1.14,2.44]) than non-vegetarians after adjustment for potential confounding factors. Conclusions: Vegetarian men have more depressive symptoms after adjustment for socio-demographic factors. Nutritional deficiencies (e.g. in cobalamin or iron) are a possible explanation for these findings, however reverse causation cannot be ruled out.
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Journal of Aective Disorders
journal homepage:
Research paper
Vegetarian diets and depressive symptoms among men
Joseph R. Hibbeln
, Kate Northstone
, Jonathan Evans
, Jean Golding
Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, NIH, Rockville, MD, USA
School of Social and Community Medicine, University of Bristol, UK
Nutritional psychiatry
Background: Vegetarian diets are associate with cardiovascular and other health benets, but little is known
about mental health benets or risks.
Aims: To determine whether self-identication of vegetarian dietary habits is associated with signicant de-
pressive symptoms in men.
Method: Self-report data from 9668 adult male partners of pregnant women in the Avon Longitudinal Study of
Parents and Children (ALSPAC) included identication as vegetarian or vegan, dietary frequency data and the
Edinburgh Post Natal Depression Scale (EPDS). Continuous and binary outcomes were assessed using multiple
linear and logistic regression taking account of potential confounding variables including: age, marital status,
employment status, housing tenure, number of children in the household, religion, family history of depression
previous childhood psychiatric contact, cigarette and alcohol consumption.
Results: Vegetarians [n = 350 (3.6% of sample)], had higher depression scores on average than non-vegetarians
(mean dierence 0.96 points [95%CI + 0.53, + 1.40]) and a greater risk for EPDS scores above 10 (adjusted OR
= 1.67 [95% CI: 1.14,2.44]) than non-vegetarians after adjustment for potential confounding factors.
Conclusions: Vegetarian men have more depressive symptoms after adjustment for socio-demographic factors.
Nutritional deciencies (e.g. in cobalamin or iron) are a possible explanation for these ndings, however reverse
causation cannot be ruled out.
1. Introduction
Vegetarian diets have been associated with decreased risks of car-
diovascular death, obesity and diabetes (Fraser, 2009) prompting
questions as to whether potential benets extend to mental health or, in
contrast, whether diminished intakes of nutrients that are abundant in
excluded foods cause adverse consequences to mental well-being
(Beezhold et al., 2010). A large survey of Australian women in their
20's, found a signicant increase in elevated depressive symptoms
among vegetarians compared to non-vegetarians (22% v. 15%) (Baines
et al., 2007). Among 1046 Australian women, lower red meat con-
sumption was associated with nearly a doubling of risk for major de-
pressive and anxiety disorders (Jacka et al., 2012). Among Norwegian
students, nearly twice as many men and one third more women with
low meat consumption reported having been depressed, after adjust-
ment (Larsson et al., 2002). In a representative sample, depression was
more common among completely and predominantly vegetarian
German adults, but adoption of vegetarian diets followed the onset of
mental illnesses (Michalak et al., 2012). In Minnesota, adolescent ve-
getarians were more likely to have eating disorders and to have
contemplated and attempted suicide (Perry et al., 2001) and Turkish
adolescent vegetarians had higher social and physique anxiety scores
(Bas et al., 2005). In contrast, a small survey of Seventh Day Adventist
adults found no increased risk of depression or anxiety among vege-
tarians who excluded sh (Beezhold et al., 2010). Not all diets identi-
ed as vegetarian are homogeneous, with some including sh, rich in
omega-3 highly unsaturated fatty acids (omega-HUFAs) and some
meats and others excluding eggs (a source of omega-3 HUFAs and vi-
tamins) and dairy products. Omega-3 HUFA's, specically docosahex-
aenoic acid, are selectively concentrated in synaptic membranes and
are essential for optimal neural function (Salem and Niebylski, 1995).
Meta-analyses of randomized controlled trials indicate that omega-3
HUFAs are eective in treating signicant depressive symptoms (Grosso
et al., 2014; Hallahan et al., 2016). Red meats are a rich source of vi-
tamin B
and data suggest that low levels of vitamin B
and folate may
increase the risk of depression (Stanger et al., 2009) and one meta-
analysis suggests that vitamin B
intervention may prevent depressive
symptoms in specialized populations (Almeida et al., 2015). Decits in
zinc and iron have also been postulated as risk factors in depression: a
systematic review found evidence of benets but cautioned that well-
Received 13 February 2017; Received in revised form 24 July 2017; Accepted 27 July 2017
Correspondence to: Section on Nutritional Neurosciences, NIAAA, NIH, 5625 Fishers lane, Room 3N-07, Rockville, MD 20892, USA.
E-mail address: (J.R. Hibbeln).
Journal of Affective Disorders 225 (2018) 13–17
Available online 28 July 2017
0165-0327/ © 2017 Published by Elsevier B.V.
designed randomized controlled trials are needed to better evaluate
eects of improving iron and zinc status on mood and cognition
(Lomagno et al., 2014).
Although there has been considerable attention paid to maternal
depression and its eect on child development, studies from ALSPAC
have reported associations between paternal depression and adverse
eects on the developing child (Ramchandani et al., 2005, 2008).
Consequently, recognizing and ameliorating paternal depression is
important. We sought to determine whether self-identication of a
vegetarian diet was associated with increased risk of depressive
symptoms among adult men during the pregnancy of their partners.
2. Methods
The Avon Longitudinal Study of Parents and Children (ALSPAC)
(Fraser et al., 2013; Golding et al., 2001) enrolled women resident in
the former geographical area of Avon in south-west England who were
in the early stages of pregnancy with an expected date of delivery be-
tween 1st April 1991 and 31st December 1992. ALSPAC is an ongoing
population based cohort study investigating environmental and other
inuences on the health and development of children; Please note that
the study website contains details of all the data that are available
through a fully searchable data dictionary:
In the event, 14,541 pregnancies were enrolled. Detailed informa-
tion was obtained from the women and their partners via self-comple-
tion questionnaires. The partner's participation was through an opt-in
process determined primarily by the woman. She was sent a ques-
tionnaire at 18 weeks gestation to complete and an additional one for
her partner to complete if she wanted him to participate in the study.
9845 male partners responded to this questionnaire which included
data on diet and mood as well as demographic and psychosocial vari-
The Edinburgh Postnatal Depression Scale (Cox et al., 1987) was
given to male partners as well as mothers in this study. This was sent as
part of the 18 week questionnaire and was generally completed be-
tween 18 and 20 weeks of their partner's gestation. This scale focuses on
cognitive and aective features of depression rather than somatic
symptoms. Although the EPDS was developed to screen for depression
in women postnatally it has been found to be useful in women outside
the postnatal period and in men (Areias et al., 1996a, 1996b; Cox et al.,
1996, 1987). The scale cannot in itself conrm a diagnosis of depressive
disorder; however a score above 12 has been shown to indicate a high
probability of severe depression. Although considered univariably, such
a cut-owould result in limited statistical power for the multivariable
analyses in the present study and therefore scores above 10, which will
include more cases with mild and moderate depression, have been
considered in the logistic regression analyses.
Background data on the study fathers were collected by means of
two postal questionnaires administered to them in pregnancy. These
data included vulnerability factors for depression such as a family
history of depression, previous childhood psychiatric contact (through
attendance at a child guidance clinic) and the highest educational level
reached. Data on current circumstances that might lead to higher scores
when rating depressed mood included housing tenure, age, ethnic
origin and number of children in the household. Vegetarianism is more
common amongst certain religious groups and therefore religion was
included in the analyses, grouped as Christian, non-Christian or none.
Other factors such as marital status, employment status, alcohol and
tobacco consumption might result from depressed mood as well as
being causal factors and so these were additionally adjusted for in a
separate analysis. Responses to the postal questionnaire on diet at 32
weeks maternal gestation were used as the basis for allocating subjects
to vegetarian or non-vegetarian groups. Men were asked if they were
either vegetarian or vegan or neither. Because there were relatively few
vegans, they have been combined with the vegetarians in this paper. In
a preceding set of questions the men were asked how many times
nowadays do you eat: followed by 17 categories of foods consumed
either never, once in 2 weeks, 13 times per week, 47 times/week or
more than once per day. In order to evaluate dietary exclusion, these
categories were collapsed to yesor never.
3. Statistical methods
The depression scores for the EPDS were strongly skewed to the left:
17.5% of the whole sample scored zero. Transformation of the data did
not produce a closer approximation to a normal distribution due to
these zero values. Hence the EPDS data were analyzed untransformed
using both parametric (t-test or ANOVA where appropriate) and non-
parametric (Mann-Whitney Utest or Kolmogorov-Smirnov test where
appropriate) tests for univariable analysis, comparing the dierences in
mean scores. In addition, cut points of both > 10 and > 12 were used
to create a binary variable for EPDS; chi-squared tests for independence
were used to determine any signicant dierences in proportions above
these values. General linear models and multiple logistic regression
(with the binary depression score based on EPDS > 10 as the dependent
variable) were used to investigate any independent relationship with
vegetarianism. Exclusions were made only on the basis of missing data.
A substantial number of men (20%) did not answer the question about
marital status so an unknown category was included in the analysis to
maintain statistical power.
4. Results
4.1. Unadjusted associations
EPDS scores were available from 9668 men who also provided in-
formation on their vegetarian status. 350 (3.6%) reported that they
were vegetarian/vegan (311 vegetarian and 39 vegan). The length of
time that these men reported that they had been vegetarian ranged
from < 1 to 41 years, with two-thirds having been vegetarian for < 10
years. Vegetarians had a higher mean depression score compared to
non-vegetarians (p < 0.0001 for both t-test and Mann-Whitney), simi-
larly a greater proportion of vegetarians had an EPDS score > 10 (p =
0.001) with an unadjusted odds ratio of 1.75 (95% CI: 1.26, 2.43)
compared to non-vegetarians (Table 1). The reported duration of ve-
getarianism showed a trend towards higher depression scores with in-
creasing length of time (p = 0.103).
Table 2 shows associations between various social and lifestyle
factors and both vegetarian status and EPDS scores greater than 10.
Men who had an EPDS score greater than 10 were more likely to have
lower levels of education, to live in council or other rented accom-
modation, have more children in the home and be under 25 years of
age. Non-married men, those who had contact in childhood with the
child psychiatric services, heavy smokers and unemployed men were
also more likely to have a higher EPDS score. Men self-reporting as
vegetarian were more likely to have higher levels of education, to live
in privately rented accommodation, to have no children in the
Table 1
Distribution of EPDS score in whole sample and in vegetarians and non-vegetarians.
Vegetarians Non-vegetarians Overall
N 350 9318 9668
Mean 5.26
4.18 4.22
St Dev 4.54 3.89 3.93
% (n) score > 10 12.3% (43)
7.4% (690) 7.6% (733)
%(n) score > 12 6.8% (24)
3.9% (366) 4.0% (390)
Mean EPDS score compared to non-vegetarians F = 25.41, p < 0.0001 (M-W:
p < 0.0001).
Proportion with score > 10 compared to non-vegetarians χ
= 11.5, p = 0.001.
Proportion > 12 compared to non-vegetarians ×
= 8.1, p < 0.01.
J.R. Hibbeln et al. Journal of Affective Disorders 225 (2018) 13–17
household and to be of non-white ethnic origin. Vegetarian men re-
ported lower consumption of sausages, burgers, meat pies, meat,
poultry, liver and white sh than omnivores, but were just as likely to
have consumed some oily sh and shellsh (Table 3).
They were also more likely to be unmarried, of a religion other than
Christian and to be unemployed. There were no associations evident
with age, family history of depression, childhood psychiatric contact or
with cigarette smoking.
4.2. Adjusted associations
Factors independently associated with EPDS (on multivariable
analysis) were housing tenure, number of children in the household,
religion, family history of depression and child guidance, all in the same
direction as described above. A second analysis also evaluated cigarette
and alcohol consumption, marital status and employment status. With
the exception of cigarette consumption all these factors were also in-
dependently associated with EPDS score > 10.
After adjusting for those social and lifestyle variables, there was still
evidence of an association with vegetarianism when treating EPDS as a
continuous outcome (Table 4). This resulted in a mean score dierence
of + 1.00 [95% CI + 0.56, + 1.43] after allowing for those factors
Table 2
Patterns of association between life style factors and both vegetarianism and EPDS >10
Test for trend).
Total no.
% (n) % (n)
Vegetarian EPDS
score > 10
Highest Educational level
CSE or less (21.2%) 2060 42 (2.0%) 214 (10.7%)
Vocational (8.3%) 803 23 (2.9%) 78 (9.9%)
O Level (22.7%) 2198 73 (3.3%) 142 (6.6%)
A Level (28.1%) 2723 86 (3.2%) 171 (6.4%)
Degree (19.7%) 1912 127 (6.6%) 111 (5.9%)
(p) 63.4 (< 0.0001) 50.6 (< 0.0001)
(p) 45.4 (< 0.0001) 43.7 (< 0.0001)
Housing Tenure
Mortgage/owned (77.1%) 7342 255 (3.5%) 426 (5.9%)
Council (11.6%) 1104 25 (2.3%) 141 (13.0%)
Rented/Other (11.3%) 1079 63 (5.8%) 130 (12.3%)
(p) 21.6 (< 0.0001) 110.0
(< 0.0001)
Children in Household
None (44.3%) 4095 171 (4.2%) 225 (5.6%)
1 (36.6%) 3379 108 (3.2%) 259 (7.8%)
2 + (19.1%) 1766 51 (2.9%) 155 (8.9%)
(p) 8.12 (0.017) 25.4 (< 0.0001)
(p) 7.46 (0.006) 24.4 (< 0.0001)
White (97.2%) 9412 318 (3.4%) 690 (7.4%)
Non-white (2.8%) 276 30 (10.9%) 28 (10.6%)
(p) 43.5 (< 0.0001) 3.7 (0.055)
< 25 (16.3%) 1601 56 (3.5%) 185 (12.0%)
25-29 (33.3%) 3274 105 (3.2%) 209 (6.5%)
30-34 (31.1%) 3066 109 (3.6%) 181 (6.0%)
35+ (19.3%) 1904 86 (4.5%) 158 (8.4%)
(p) 6.1 (0.107) 62.1 (< 0.0001)
(p) 3.6 (0.059) 11.3 (0.001)
Marital Status
Single (10.4%) 1025 73 (7.1%) 103 (10.2%)
Married (65.4%) 6436 189 (2.9%) 359 (5.7%)
322 16 (5.0%) 37 (11.6%)
Unknown (20.9%) 2062 78 (3.8%) 234 (11.7%)
(p) 46.5 (< 0.0001) 99.3 (< 0.0001)
None (25.8%) 2460 154 (6.3%) 168 (6.9%)
Christian (68.2%) 6513 117 (1.8%) 485 (7.6%)
Other (6.0%) 575 68 (11.8%) 55 (9.8%)
(p) 226.3
(< 0.0001)
5.5 (0.065)
Family history of
Yes (23.5%) 1849 81 (4.4%) 191 (10.4%)
No (76.5%) 6513 199 (3.3%) 313 (5.3%)
(p) 4.8 (0.069) 61.2 (< 0.0001)
Childhood contact with
psychiatric services
Yes (3.4%) 254 11 (4.3%) 27 (10.8%)
No (96.6%) 7326 255 (3.5%) 451 (6.2%)
(p) 0.5 (0.469) 8.5 (0.004)
No. cigarettes daily
None (67.3%) 6501 236 (3.6%) 400 (6.3%)
1-9 (9.2%) 887 41 (4.6%) 70 (8.0%)
10+ (23.5%) 2275 68 (3.0%) 246 (11.0%)
(p) 5.2 (0.076) 53.0 (< 0.0001)
(p) 1.2 (0.268) 52.6 (< 0.0001)
Daily alcohol consumption
< 1 glass/ week (29.2%) 2825 121 (4.3%) 258 (9.3%)
1+ glasses/week (50.4%) 4865 163 (3.4%) 304 (6.3%)
1+ glasses/day (20.4%) 1970 63 (3.2%) 144 (7.4%)
(p) 5.6 (0.061) 22.4 (< 0.0001)
(p) 4.6 (0.033) 8.4 (0.004)
Yes (88.2%) 8683 297 (3.4%) 561 (6.6%)
No (118.8%) 1162 59 (5.1%) 172 (15.4%)
(p) 8.1 (0.004) 92.8 (< 0.0001)
Table 3
Self-identication as a vegetarian, or non-vegetarian, and reported food consumption
from food frequency questionnaire.
Vegetarian Non-vegetarian
Food category
n (%) n (%)
Sausage/Burger 22 (7.4) 6992 (75.6)
Meat pie 31 (10.3) 6660 (72.2)
Meat 14 (4.7) 8981 (94.2)
Poultry 37 (12.3) 8782 (91.9)
Oal 4 (1.3) 2128 (23.1)
White sh 174 (57.6) 7467 (80.8)
Oily sh 158 (52.3) 4758 (51.6)
Shellsh 86 (28.6) 2150 (23.3)
Fried food 163 (54.3) 7121 (77.1)
Green leafy vegetables 276 (91.7) 8112 (87.8)
Carrots 293 (96.7) 8422 (91.1)
Other vegetables 299 (98.4) 8877 (96.4)
Salad 294 (97.0) 7907 (85.7)
Fresh fruit 292 (96.1) 7984 (86.4)
Fruit juice (tin) 66 (22.5) 2096 (22.9)
Pure fruit juice 260 (86.1) 6438 (69.8)
Nuts 254 (83.3) 3211 (34.8)
Any positive response to current consumption of food items.
Table 4
Association between vegetarianism and EPDS scores after adjustment for other factors.
Adjusted associations
EPDS as continuous score EPDS score > 10
β(95%CI) OR (95%CI)
Model 1
Yes 1.00 (0.56, 1.43) 1.71 (1.17, 2.49)
No 0.00 Reference 1.00 Reference
F = 20.12 (p < 0.0001)
Model 2
Yes 0.96 (0.53, 1.40) 1.67 (1.14, 2.44)
No 0.00 Reference 1.00 Reference
F = 18.58 (p < 0.0001)
Adjusted for housing tenure, number of children in the household, age, religion, fa-
mily history of depression, child psychiatric contact (not independently signicant:
education, ethnicity, oily sh consumption).
As for Model 1 but also oering alcohol and tobacco consumption, marital and em-
ployment status.
J.R. Hibbeln et al. Journal of Affective Disorders 225 (2018) 13–17
which were independent of the depressed state, (model 1), and only a
slight change after also allowing for the 4 factors (alcohol, tobacco etc.)
which may have been a consequence of the depression (model 2). When
using a binary outcome variable, there was an elevated odds ratio for an
EPDS score greater than 10 and vegetarianism: for model 1: 1.71 (95%
CI: 1.17, 2.49; p = 0.005) and this was barely attenuated when the
additional variables were added in model 2 [adjusted Odds ratio =
1.67 (95% CI: 1.14, 2.44); p = 0.009].
5. Discussion
To our knowledge this is the rst large epidemiological study to
show a relationship between vegetarianism and signicant depressive
symptoms among adult men. Here we found that self identication as
a vegetarian was associated with an increased risk of depressive
symptoms evaluated both as a continuous scale and using a cut-oof
greater than 10 on the EPDS. These associations remained after ad-
justment for vulnerability factors for depression including a family
history of depression, previous childhood psychiatric contact, highest
educational level reached, housing tenure, age, ethnic origin, number of
children in the household, marital status, employment status, alcohol
and tobacco consumption and religious identication. There was a
trend evident comparing the duration of vegetarianism and depressed
mood although this failed to reach signicance (data not shown).
Several possible factors previously linked to an increased risk of
depressive symptoms might underlie this increased risk of depression
among vegetarians. Any adverse eect on mood associated with vege-
tarian diet may result from contributions from multiple interactive
nutrients including both type and quantity of dietary fat intake between
vegetarians and non-vegetarians. For example, vegetarians are known
to have lower intakes of n-3 HUFAs, vitamin B
and folate, greater
consumption of nuts rich in omega-6 fatty acids which may be asso-
ciated with greater risk of depression (Wolfe et al., 2009) and a possibly
increased likelihood of persons with depressive symptoms to change
their dietary preferences. Other potential factors include high blood
levels of phytoestrogens (consequent mainly on diets rich in vegetables
and soya) and metabolites of pesticides (consequent upon relatively
high intakes of fruit and vegetables), which are more likely to be found
among vegetarians (Tordjman et al., 2016). Another potential con-
tributing factor is lower intakes of seafood (Li et al., 2016) and low
omega-3 HUFA blood levels (Lin et al., 2010) are thought to be asso-
ciated with greater risk of depressive symptoms. Several meta-analyses
of randomized, placebo-controlled intervention trials have found eect
sizes comparable to those of pharmaceutical antidepressants, some
specically indicating that eicosapentaenoic rich preparations are sig-
nicantly more eective (Grosso et al., 2014; Hallahan et al., 2016).
One additional concern is that people who opt for the vegetarian diet
might be intending to lose weight or that there are dierences in the
prevalence of obesity and overweight participants; medical conditions
clearly associated with depression. However, whilst non-vegetarians
had higher BMIs 25.20 (3.29) [Mean (SD)] compared to vegetarians,
24.32 (3.00) p < 0.001, depression and BMI were not associated:
EPDS < 10 25.16 (3.26) EPDS 10+ 25.27 (3.50) p = 0.405.
Since exclusion of red meat primarily characterizes vegetarians,
lower intakes of vitamin B
merit consideration as a contributing
factor. Curiously in this study, 72% of self-reported vegans and 4.7% of
vegetarians reported some current consumption of red meat (data not
shown). However, although self-identication and dietary practice may
dier substantially, self-reported vegetarians in this study are con-
siderably less likely to consume red meat or poultry than non-vege-
tarians. This is consistent with prior reports from the UK Women's co-
hort study that of the 28% of subjects self-reported as being vegetarian
and 1% as vegan, only 18% would be dened as 'vegetarian' from
dietary habits reported in a food frequency questionnaire (Cade et al.,
2004). Our ndings are also consistent with an evaluation of 1046
Australian women where lower red meat consumption was associated
with nearly a doubling of risk for major depressive and anxiety dis-
orders. A trend towards a U shaped curve, with greater risks of major
depression or dysthymia among Australian women consuming more (n
= 27) or less (n = 21) than recommended amounts was reported
(Jacka et al., 2012). However these results must be interpreted with
caution as they were only signicant for greater red meat consumption
when adjusted for traditional dietary patterns, which include meat
consumption and in comparison to n = 12 women consuming re-
commended amounts of red meat. Other than vitamin B
and dier-
ences in fat consumption, the EPIC-Oxford study indicates that dier-
ences in nutrient intake between British vegetarians are modest
compared with non- vegetarians (the few vegans excepted) (Davey
et al., 2003). The authors found that 52% of self-reported vegans and
7% of vegetarians were vitamin B
decient (dened as serum vitamin
< 118 pmol/l) (Gilsing et al., 2010). Several observational studies
have reported associations with elevations in homocystine or low vi-
tamin B
and risk of major and minor depression (Penninx et al.,
2000). DSM-IV diagnosis of depression was reduced by 50% by daily
folic acid (2 mg), vitamin B
(25 mg), and vitamin B
(0.5 mg) in a
randomized, placebo-controlled trial of survivors of stroke for 110.5
years (Almeida et al., 2010). The study presented here, as others, fails
to resolve whether the increased risk of depressive symptoms in this
population was due to lower intake of nutrients rich in red meats,
among which vitamin B
is a plausible candidate. A randomized pla-
cebo controlled trial is warranted to determine whether depressive
symptoms among vegetarians can be reduced by supplementing with
folic acid and other B vitamins to lower homocystine levels. By main-
taining sucient B vitamin and folate levels, vegetarians may be able to
have the benets of better health, and harmony with ethical and cul-
tural beliefs, while reducing risks of depressive symptoms.
Relatively few intervention trials have been conducted to assess the
eects of assignment of a vegetarian diet on mental health outcomes
and all of these studies may have methodological issues due to the
expectancy of benet and diculty in achieving adequate blinding of
dietary assignment and non-specic assessment of symptoms. In one of
these studies global mood scores improved in association with carbo-
hydrate intake and plasma tryptophan measures after six weeks on a
vegetarian diet (Schweiger et al., 1986), and in another improved
mental health, vitality and fewer impairments in work productivity
were reported after a 22 week intervention (Katcher et al., 2010).
Perhaps reasons cited by former vegetarians for resuming omnivorous
diets are also indicators of mild psychiatric eects of their dietary
changes. The reasons reported included not feeling healthy and concern
about their nutritional status (in addition to missing the taste of meat)
(Barr and Chapman, 2002).
However, it is possible that the increased risk for elevated depres-
sive symptoms found here is not related to any dietary dierences, but
is due to intrinsic dierences in rates of psychiatric or personality
problems comparing vegetarians to non-vegetarians. It is possible that
for some proportion of the population, vegetarianism is not chosen for
health, religious or ethical reasons, but is a marker for other psychiatric
disorders manifesting with symptoms of both eating disorders and de-
pressive symptoms. For example, among adolescents in Minnesota ve-
getarianism was associated with a cluster of problems including dis-
satisfaction with their bodies and unhealthy weight control practices,
especially among males, and increased suicide risk indicators (Perry
et al., 2001); Turkish vegetarian adolescents had a cluster of problems
including abnormal eating attitudes, low self-esteem, social physique
and social trait anxiety (Bas et al., 2005). However, it is unclear if this
clustering of problems among adolescents continues through to adult
populations who frequently identify health and ethical reasons for their
choice of vegetarianism. Here, self-identication as a vegetarian/vegan
was not inuenced by a parental history of depression or by childhood
contact with psychiatric services. However, subjects with depressive
symptoms are well known to have alterations in dietary preference and
appetite resulting in weight gain or weight loss. In contrast, Janelle and
J.R. Hibbeln et al. Journal of Affective Disorders 225 (2018) 13–17
Barr (1995) found no evidence of increased risk of eating disorders
among adult vegetarian women after assessing dietary restraint (con-
scious limitation of food intake), disinhibition, and hunger assessed by
the Three-Factor Eating Questionnaire.
Some methodological limitations in the study reported here need
consideration. First, there are no data on serum cholesterol or fatty
acids or vitamin B
in these subjects. Second, it is possible that by
correcting for variables that may be a consequence of depression such
as marital status, employment status, alcohol and tobacco consumption,
a realistic relationship with depression may be masked. However,
variables such as these can be both potential causes and consequences
of depression; nevertheless even when taking these variables into ac-
count the relationship remained. Another consideration is that self-re-
port questions do not allow conrmation of a diagnosis of depression
and a bias may result from non-response by depressed subjects, or the
decision by mothers to invite their partners to opt in to the study.
However the results presented here do indicate that male British ve-
getarians did have a greater risk for depressive symptoms after ad-
justing for multiple confounding variables. We also cannot rule out the
possibility of reverse causation, that is that having depressive symptoms
might change dietary habits and increase the likelihood of being a ve-
getarian. This study does not resolve the question of whether adoption
of a vegetarian diet will increase, or decrease the risk of depressive
symptoms or aect mental well-being or what specic nutrients, if any,
may inuence those risks, but does suggest that a randomized con-
trolled trial of selected nutrients or foods may be warranted.
Role of funding sources
The UK Medical Research Council and the Wellcome Trust (Grant
ref 102215/2/13/2) and the University of Bristol currently provide core
support. This publication is the work of the authors and Joseph R.
Hibbeln, Johnathon Evans, Kate Northstone and Jean Golding will
serve as guarantors for the contents of this paper. The Intramural
Research Program of the National Institute on Alcohol Abuse and
Alcoholism, the Waterloo Foundation and a personal gift from John M.
Davis, M.D. provided support for this study. The funders had no role in
the study design, collection analysis, conduct of the study nor in the
writing and preparation of the manuscript or the decision to publish.
We are extremely grateful to all the mothers and fathers who took
part in the study, to the midwives for their help in recruiting them and
the whole ALSPAC study team which includes interviewers, computer
and laboratory technicians, clerical workers, research scientists, vo-
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... Alguns dados mostram que vegetarianos, na Europa e Estados Unidos, apresentaram maior incidência de sintomas de depressão quando comparado á populações onívoras (que consomem todos os grupos alimentares). [10][11][12] É importante o estudo sobre a relação entre os hábitos alimentares vegetarianos e a depressão, pois esse conhecimento auxilia na determinação de padrões alimentares que podem prevenir e/ou auxiliar no tratamento da doença. ...
... Esta pesquisa difere de trabalhos recentes que apontam associação significativa entre a adoção de uma dieta vegetariana e maiores índices de sintomas de ansiedade e depressão. [11][12] Estudo epidemiológico, publicado em 2017, utilizou informações já existentes da Avon Longitudinal Study of Parents and Children (ALSPAC) relativas a 9.668 homens ingleses. Os autores verificaram que havia maior risco de sintomas de ansiedade e depressão entre os vegetarianos mesmo levando em consideração aspectos como fatores socioeconômicos. ...
... No entanto, afirmam que há a possibilidade de esse resultado não ter relação com o tipo de dieta adotado, e que uma parcela da população se torne vegetariana devido a problemas psiquiátricos ou de personalidade. 11 Forestell e colaboradores (2018) investigaram se havia diferença entre estudantes de graduação dos Estados Unidos, onívoros e vegetarianos, quanto a características de personalidade, incluindo a presença de sintomas de depressão medidos pela escala CES-D. 12 Os autores apontaram que vegetarianos e semivegetarianos eram mais "neuróticos" e depressivos do que os onívoros e levantaram possíveis causas, que concordam com os achados de Michalak et al (2012) -em que a linha temporal também foi estudada, e afirmam que desordens mentais podem preceder a adoção de dietas vegetarianas, cuja explicação pode ser a de que indivíduos deprimidos escolhem uma adotar uma dieta vegetariana para melhorar seu estado de saúde, por serem ricas em vitamina B6, B9 e antioxidantes. ...
Objetivo: avaliar sintomas depressivos em pacientes vegetarianos e onívoros de Pernambuco (Brasil). Método: A coleta de dados foi realizada por meio de questionário online autoaplicável, contendo a Escala de Rastreamento Populacional para Depressão do Centro de Estudos Epidemiológicos (CES-D). O instrumento é composto por 20 questões, cujas respostas ajudam a detectar sintomas de depressão em populações adultas. Para análise dos dados, foram utilizados média e desvio padrão, e valores de p e teste de Student Um total de 106 indivíduos responderam o questionário, sendo destes 53 onívoros e 53 vegetarianos. Resultados: ambos os grupos, onívoros e vegetarianos, apresentaram um score aumentado para depressão (acima de 16 pontos). Estes escores não diferem de acordo com estilo de dieta, não havendo diferença estatística entre os grupos. Não houve associação entre dietas vegetarianas e sintomas depressivos, pelo menos no aspecto clínico e com a escala escolhida. Conclusão: ressalta-se a importância de avaliar o aumento dos escores em ambos os grupos. Mais estudos são necessários para elucidar esses mecanismos. Descritores: Transtornos Mentais; Alimentação; Saúde Mental.
... Yet again, the cross-sectional design of the study did not allow for determining causality. Likewise, Hibbeln et al. 12 reported a higher frequency of depressive symptoms in vegetarian men after adjustment for sociodemographic factors. Vegetarians in this particular cohort from South West England had higher average depression scores than non-vegetarians (mean difference: 0.96 points [CI: +0.53 to +1.40]). ...
... 15 Said potential deficiencies, partic-ularly in omega-3-fatty acids, vitamin B 12, iron, and folate, could be a potential explanation for the higher odds of depression in vegetarians observed in several studies. 12,15,50 Finally, it is of paramount importance to consider lifestyle factors and behaviors when discussing about vegetarian diets and their association with depression. Vegetarians frequently yield a healthier lifestyle with higher levels of physical activity as compared to non-vegetarians. ...
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Objective: Adherence to vegetarian diets has been associated with physical health benefits, whereas vegetarian mental health is less well documented. We sought to investigate whether adherence to a vegetarian diet was associated with depression in a nationally-representative sample of US adults. Methods: We used population-based data from the US National Health and Nutrition Examination Surveys to examine said associations. Depression was assessed using the Patient Health Questionnaire (PHQ-9), vegetarian status was self-reported. Multivariate regression was used to measure the magnitude of associations, controlling for a range of covariables known to be associated with depressive symptoms. Results: Our analysis included 9,584 individuals, of which 910 individuals had PHQ-9 scores suggestive of depression. Vegetarian diet was associated with reduced odds of PHQ-9 defined depression (odds ratio [OR]: 0.49 [95% confidence interval {CI}: 0.24–0.98], p=0.047) in a model adjusting for sex, age, ethnicity, income, and marital status. When adjusting for additional factors (educational level, smoking status, serum C-reactive protein, and body mass index) in a second model, the previously observed association was no longer significant (OR: 0.66 [CI: 0.34–1.26], p=0.203). Conclusion: Vegetarian diet was not associated with PHQ-9 defined depression in this nationally-representative sample of adults. Additional longitudinal examinations are warranted to evolve the understanding of the role of vegetarian diets in mental health.
... The prevalence of vegetarianism may vary according to income level. Rammohan et al. (2012) indicated that poverty and the high cost of meat were reasons for choosing a vegetarian diet, while some other studies have indicated that people with a higher income are more likely to be vegetarians for health and environmental reasons [47,48]. ...
... In contrast to these studies, a study conducted on university students in the USA showed that vegetarians were more likely to suffer from neuroticism and depression than omnivores [47]. A study found that the risk of depression among vegetarian men was 1.67 times higher than the risk for nonvegetarians [48]. This might be due to an increased risk of deficiencies in certain nutrients, such as iron (64-66), zinc (67,68), omega-3 (69-72), vitamin B 12 (73-75), and vitamin D (76-78). ...
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Background In recent years, there has been great interest in the dietary practices of vegetarians in addition to an increasing awareness of the potential benefits of vegetarian diets. However, there are insufficient data on the spread of vegetarianism in Arab countries. The aim of this study was to investigate knowledge and attitudes about vegetarianism and associated factors in the Saudi population and to understand the reasons for its growing prevalence. Method This is a cross-sectional study began in May 2020 and ended in September 2020. Researchers distributed the questionnaire electronically through social media. Data were collected electronically and exported to Excel by the researchers .The electronic questionnaire comprised three sections: sociodemographic questions, reasons for following a vegetarian diet, and beliefs and knowledge about vegetarianism. Results There were 3,035 responses, of which 80.2% of respondents were female and 19.8% were male. Participant were aged 18–65. Vegetarians represented 37.5% (15.7% semivegetarians, 8.1% pescovegetarians, 64.3% lacto-ovo-vegetarians, and 11.3% vegans), and the rest were nonvegetarians. The majority of the vegetarian participants (92.9%) had a low vegetarianism knowledge level. Health issues, followed by ethical and environmental concerns, were the most common motivators for adopting a vegetarian diet; these reasons were cited by 72.5%, 59.3%, and 47.9% of participants, respectively. Factors associated with increased vegetarianism were engaging in exercise for half an hour to two hours, while factors associated with decreased vegetarianism were male, aged 51–64 years, being married, having a higher education, working in the health sector, being a housewife, and having an income between 5,000 and 10,000 SR/month. Conclusion Vegetarianism appears to be a growing phenomenon among the Saudi population. Increased awareness of health issues and the desire to live a healthy lifestyle might be the strongest motives. This study offers an opportunity to better understand vegetarianism in Saudi Arabia along with the possibility of expanding vegetarian food choices for the general public.
... Conversely, nutritional deficiencies in a plant-based diet could be involved in the increase of depressive symptoms. One study showed that 52% of vegans and 7% of vegetarians were deficient in vitamin B12 [70], a vitamin generally gained through red meat consumption and thought to help combat depressive symptoms [38]. Similarly, omega-3 polyunsaturated fatty acids play a vital role in brain function and are linked with mood outcomes [33]. ...
... Literature on plant-based diets and depressive symptoms is ambiguous. Some studies found that plant-based diets were associated with a risk of depressive symptoms [42,70]. Other studies only concluded gender differences; male vegetarians demonstrated higher depression than male omnivores, but females did not [38]. ...
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Dietary patterns and depressive symptoms are associated in cross-sectional and prospective-designed research. However, limited research has considered depression risk related to meat-based and plant-based dietary patterns. This study explores the association between diet quality and depressive symptoms across omnivore, vegan, and vegetarian dietary patterns. A cross-sectional online survey utilised the Dietary Screening Tool (DST) and the Centre for Epidemiological Studies of Depression Scale (CESD-20) to measure diet quality and depressive symptoms, respectively. A total of 496 participants identified as either omnivores (n = 129), vegetarians (n = 151), or vegans (n = 216). ANOVA with Bonferroni post hoc corrections indicates that dietary quality was significantly different between groups F(2, 493) = 23.61, p < 0.001 for omnivores and vegetarians and omnivores and vegans. Diet quality was highest in the vegan sample, followed by vegetarian and omnivore patterns. The results show a significant, moderately negative relationship between higher diet quality and lower depressive symptoms (r = −0.385, p < 0.001) across groups. Hierarchical regression showed that diet quality accounted for 13% of the variability in depressive symptoms for the omnivore sample, 6% for vegetarians, and 8% for vegans. This study suggests that diet quality in a meat-based or plant-based diet could be a modifiable lifestyle factor with the potential to reduce the risk of depressive symptoms. The study indicates a greater protective role of a high-quality plant-based diet and lower depressive symptoms. Further intervention research is needed to understand the bi-directional relationship between diet quality and depressive symptoms across dietary patterns.
... In this study, ILR group subjects showed an inverse relationship between anxiety scores and meat intake at the 3-month follow-up. In line with this finding, studies that have examined the association between a vegetarian diet and mental disorders reported that low levels of depression or anxiety are associated with a high consumption of meat [70][71][72]. However, other studies showed opposite findings and reported that meat avoidance is associated with better mental health [73,74]. ...
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Background Psychological status affects dietary intake, and recognizing genetic information can lead to behavior changes by influencing psychological factors such as anxiety or depression.Objectives In this study, we examined the effects of disclosing genetic information on anxiety or depression levels and the association between these psychological factors and dietary intake.MethodsA total of 100 healthy adults were randomly assigned to an intervention group (n = 65) informed about their genetic test results regarding body mass index and lipid profiles (triglyceride and cholesterol concentrations) and a not-informed control group (CON, n = 35). Based on polygenic risk scores, participants in the intervention group were subclassified into an intervention-low risk (ILR, n = 32) and an intervention-high risk (IHR, n = 33) group. Nutrient and food intakes were assessed via a 3-day dietary record at baseline and at 3 and 6 months. Depression and anxiety levels were measured using PHQ-9 and GAD-7 questionnaires, and the relative levels of blood metabolites were measure using GC-MS/MS analysis.ResultsNoticeable changes in dietary intake as well as psychological factors were observed in male subjects, with those perceiving their genetic risks as low (ILR) showing a significant increase in protein intake at 3 months compared to baseline (ILR: 3.9 ± 1.4, p
... The results of some studies indicate a correlation between the use of a plant-based diet and the occurrence of depression [29,30,31]. In a comparative study of mood, lifestyle, and diet among vegans and people on a conventional diet, herbivores had better mental health associated with less stress and anxiety [32]. ...
... Exploring this further, we found that many articles referred to the health aspect of VEG as the respondents' motivation [42,143]. Some authors explained the positive effect of VEG on the human body by mentioning specific benefits, such as reducing cholesterol, blood pressure, or risk of diabetes, as well as reducing the incidence of cancers, heart disease, and hypertension [2,3,63,144]. More recently, a body of research interested in a more holistic view of health considered VEG options as an essential contributor to well-being and quality of life [8,53,115]. ...
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Meat production and consumption are sources of animal cruelty, responsible for several environmental problems and human health diseases, and contribute to social inequality. Vegetarianism and veganism (VEG) are two alternatives that align with calls for a transition to more ethical, sustainable, and healthier lifestyles. Following the PRISMA guidelines, we conducted a systematic literature review of 307 quantitative studies on VEG (from 1978 to 2023), collected from the Web of Science in the categories of psychology, behavioral science, social science, and consumer behavior. For a holistic view of the literature and to capture its multiple angles, we articulated our objectives by responding to the variables of “WHEN,” “WHERE,” “WHO,” “WHAT,” “WHY,” “WHICH,” and “HOW” (6W1H) regarding the VEG research. Our review highlighted that quantitative research on VEG has experienced exponential growth with an unbalanced geographical focus, accompanied by an increasing richness but also great complexity in the understating of the VEG phenomenon. The systematic literature review found different approaches from which the authors studied VEG while identifying methodological limitations. Additionally, our research provided a systematic view of factors studied on VEG and the variables associated with VEG-related behavior change. Accordingly, this study contributes to the literature in the field of VEG by mapping the most recent trends and gaps in research, clarifying existing findings, and suggesting directions for future research.
... ALSPAC women scoring 12+ being at risk of clinical depression (Kwong, 2019), but ALSPAC partners rarely attain a score of 12, and we have therefore used a score of 10+ for partners as with previous research (e.g. Hibbeln et al., 2018). ...
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Background: The COVID-19 pandemic resulted in increased rates of mental health problems. We examined the possible role of the personality characteristic, Locus of Control (LOC), in moderating pandemic-induced stress. Methods: The UK-based Avon Longitudinal Study of Parents & Children (ALSPAC), 7021 adults (mean ages: women 57.6 (SD = 4.48); partners 60.5 (SD = 5.36)) responded to a 2020 questionnaire which included a generalised measure of LOC. Between March 2020-January 2021, questionnaires focussed on the pandemic were administered, which included measures of mental health. Over 60 % of respondents completed questionnaires at three timepoints of interest. Results: In those with an internal LOC higher rates of positive well-being and reduced likelihood of anxiety and depression were shown compared to those who were external, e.g. after adjustment for socioeconomic/demographic factors mean differences in well-being score for internal compared with external women was +2.01 (95%CI +1.02,+2.10) p = 0.0001; for their partners +2.52 (95%CI +1.22,+3.82) p = 0.0002. External women were more likely than internals to have depression (adjusted OR 3.41 [95%CI 1.77,6.57] p < 0.0005. Limitations: Attrition is a problem in this 30-year-old longitudinal cohort. Those still participating are more likely to have higher education and SES levels, be female and have an internal LOC. This population suffers from a lack of ethnic diversity. Conclusions: Having an internal LOC positively moderated the effects of pandemic-induced stress on the frequency of anxiety and depression in middle-age. Programmes geared to raise internality and coping strategies may have long-term benefits on well-being in stressful situations, especially for women and frontline health professionals.
... Além disso, este é único dos 4 índices que leva em consideração o consumo de bebidas açucaradas, onde seu alto consumo pode produzir um aumento na atividade do eixo hipotálamo-hipófi se-adrenal, o que pode aumentar os níveis de cortisol e, portanto, o risco de depressão 42 . Porém, não foram constatadas fortes associações entre a dieta DASH e a incidência de depressão neste estudo 29 . ...
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Introdução: A depressão é considerada a maior causa global de "anos vividos com defi ciência" e afeta cerca de 322 milhões de pessoas no mundo. Objetivo: identifi car a infl uência do padrão alimentar, baseado nas dietas Mediterrânea, Vegetariana ou Dietary Approach to Stop Hypertension (DASH), sobre a depressão. Materiais e Métodos: Foi realizada uma revisão integrativa da literatura por meio de buscas de artigos científi cos nas bases de dados eletrônicas Medline e Lilacs. Resultados: A dieta Mediterrânea foi o padrão alimentar que apresentou maior número de estudos e foi associada com a menor chance de desenvolvimento da depressão e de sintomas depressivos. A dieta Vegetariana apresentou resultados controversos e apenas 2 estudos sobre dieta DASH foram identifi cados, mas todos demonstraram efeitos benéfi cos da dieta sobre a doença. Conclusão: A promoção dos padrões alimentares baseados na dieta Mediterrânea ou DASH podem ser uma estratégia para a prevenção e tratamento da depressão. Já na dieta Vegetariana deve-se atentar a defi ciências de nutrientes, como de proteínas e vitamina B12, que parecem contribuir para o surgimento da doença. ABSTRACT Introduction: Depression is considered the leading global cause of "years lived with a disability" and aff ects around 322 million people worldwide. Objective: to identify the infl uence of dietary patterns, based on the Mediterranean, Vegetarian or Dietary Approach to Stop Hypertension (DASH) diets on depression. Materials and Methods: An integrative literature review was carried out through searches of scientifi c articles in the electronic databases Medline and Lilacs. Results: The Mediterranean diet was the dietary pattern with the largest number of studies and was associated with a lower chance of developing depression and depressive symptoms. The Vegetarian diet has shown controversial results and only 2 studies on the DASH diet have been identifi ed, but all have shown benefi cial eff ects of the diet on the disease. Conclusion: The promotion of dietary patterns based on the Mediterranean diet or DASH can be a strategy for the prevention and treatment of depression. On the other hand, the Vegetarian diet must pay attention to nutrient defi ciencies, such as proteins and vitamin B12, which seem to contribute to the onset of the disease.
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Background: Trials evaluating efficacy of omega-3 highly unsaturated fatty acids (HUFAs) in major depressive disorder report discrepant findings. Aims: To establish the reasons underlying inconsistent findings among randomised controlled trials (RCTs) of omega-3 HUFAs for depression and to assess implications for further trials. Method: A systematic bibliographic search of double-blind RCTs was conducted between January 1980 and July 2014 and an exploratory hypothesis-testing meta-analysis performed in 35 RCTs including 6665 participants receiving omega-3 HUFAs and 4373 participants receiving placebo. Results: Among participants with diagnosed depression, eicosapentaenoic acid (EPA)-predominant formulations (>50% EPA) demonstrated clinical benefits compared with placebo (Hedge's ITALIC! G= 0.61, ITALIC! P<0.001) whereas docosahexaenoic acid (DHA)-predominant formulations (>50% DHA) did not. EPA failed to prevent depressive symptoms among populations not diagnosed for depression. Conclusions: Further RCTs should be conducted on study populations with diagnosed or clinically significant depression of adequate duration using EPA-predominant omega-3 HUFA formulations.
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Iron and zinc are essential minerals often present in similar food sources. In addition to the adverse effects of frank iron and zinc-deficient states, iron insufficiency has been associated with impairments in mood and cognition. This paper reviews current literature on iron or zinc supplementation and its impact on mood or cognition in pre-menopausal women. Searches included MEDLINE complete, Excerpta Medica Database (EMBASE), psychINFO, psychARTICLES, pubMED, ProQuest Health and Medical Complete Academic Search complete, Scopus and ScienceDirect. Ten randomized controlled trials and one non-randomized controlled trial were found to meet the inclusion criteria. Seven studies found improvements in aspects of mood and cognition after iron supplementation. Iron supplementation appeared to improve memory and intellectual ability in participants aged between 12 and 55 years in seven studies, regardless of whether the participant was initially iron insufficient or iron-deficient with anaemia. The review also found three controlled studies providing evidence to suggest a role for zinc supplementation as a treatment for depressive symptoms, as both an adjunct to traditional antidepressant therapy for individuals with a diagnosis of major depressive disorder and as a therapy in its own right in pre-menopausal women with zinc deficiency. Overall, the current literature indicates a positive effect of improving zinc status on enhanced cognitive and emotional functioning. However, further study involving well-designed randomized controlled trials is needed to identify the impact of improving iron and zinc status on mood and cognition.
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Despite omega-3 polyunsaturated fatty acids (PUFA) supplementation in depressed patients have been suggested to improve depressive symptomatology, previous findings are not univocal. To conduct an updated meta-analysis of randomized controlled trials (RCTs) of omega-3 PUFA treatment of depressive disorders, taking into account the clinical differences among patients included in the studies. A search on MEDLINE, EMBASE, PsycInfo, and the Cochrane Database of RCTs using omega-3 PUFA on patients with depressive symptoms published up to August 2013 was performed. Standardized mean difference in clinical measure of depression severity was primary outcome. Type of omega-3 used (particularly eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) and omega-3 as mono- or adjuvant therapy was also examined. Meta-regression analyses assessed the effects of study size, baseline depression severity, trial duration, dose of omega-3, and age of patients. Meta-analysis of 11 and 8 trials conducted respectively on patients with a DSM-defined diagnosis of major depressive disorder (MDD) and patients with depressive symptomatology but no diagnosis of MDD demonstrated significant clinical benefit of omega-3 PUFA treatment compared to placebo (standardized difference in random-effects model 0.56 SD [95% CI: 0.20, 0.92] and 0.22 SD [95% CI: 0.01, 0.43], respectively; pooled analysis was 0.38 SD [95% CI: 0.18, 0.59]). Use of mainly EPA within the preparation, rather than DHA, influenced final clinical efficacy. Significant clinical efficacy had the use of omega-3 PUFA as adjuvant rather than mono-therapy. No relation between efficacy and study size, baseline depression severity, trial duration, age of patients, and study quality was found. Omega-3 PUFA resulted effective in RCTs on patients with bipolar disorder, whereas no evidence was found for those exploring their efficacy on depressive symptoms in young populations, perinatal depression, primary disease other than depression and healthy subjects. The use of omega-3 PUFA is effective in patients with diagnosis of MDD and on depressive patients without diagnosis of MDD.
Background: This paper describes the development of the UK Women's Cohort Study and presents cohort baseline characteristics. Methods: In total, 35,372 women, aged 35-69 years at recruitment, were selected to ensure a wide range of dietary intakes. Diet was assessed by a 217-item food-frequency questionnaire (FFQ). Detailed lifestyle information was collected by postal questionnaire. Vegetarians, fish-eaters and meat-eaters were compared. Results: The cohort women are mainly white, well-educated, middle-class and married with children. They are health-conscious with only 11% current smokers and 58% taking dietary supplements. Twenty-eight per cent of subjects self-report as being vegetarian and 1% as vegan. However, only 18% are defined as 'vegetarian' from the FFQ. Fat provides 32% of energy; vitamin and mineral intakes are high, with a broad range of intakes. Meat-eaters are older, with a higher body mass index (BMI) and the lowest intakes of carbohydrate, fibre, vitamin C, folate, iron and calcium. Other fish-eaters are similar to vegetarians. Vegetarians have the lowest intakes of protein, fat and saturated fat. Oily fish-eaters have the lowest BMI; are the least likely to smoke or use full-fat milk; and are the most likely to use dietary supplements and consume the most fruit and vegetables. Oily fish-eaters have the highest total energy intake and vegetarians the lowest. Semi-skimmed milk, bread, potatoes, wine, bananas and muesli are important contributors to energy for all groups. Conclusion: A large cohort of middle-aged women has been created encompassing a wide range of different eating patterns, including diets currently of interest to research into protection against cancer and coronary heart disease. Participants will be followed up to study the effects of different food and nutrient intakes on long-term health outcomes.
Background: The association between fish consumption and risk of depression is controversial. We performed a meta-analysis to evaluate the association. Methods: A literature search was performed in PubMed, EMBASE and Web of Science database for all relevant studies up to March 2015. We pooled the relative risks (RRs) with 95% CIs from individual studies with random effects model, and conducted meta-regression to explore potential sources of heterogeneity. Publication bias was estimated by Egger's test and the funnel plot. Results: A total of 26 studies involving 150 278 participants were included in the present meta-analysis. The pooled RR of depression for the highest versus lowest consumption of fish was 0.83 (95% CI 0.74 to 0.93). The findings remained significant in the cohort studies (RR=0.84, 95% CI 0.75 to 0.94, n=10) as well as in the cross-sectional studies (RR=0.82, 95% CI 0.68 to 1.00, n=16). When men and women were analysed separately, a significant inverse association was also observed. There was no evidence of publication bias. Conclusions: This meta-analysis indicates that high-fish consumption can reduce the risk of depression.
Background: Folate and vitamin B12 insufficiencies have been associated with increased risk of depression. This systematic review aimed to clarify if, compared with placebo, treatment with folate and/or vitamin B12 reduces depression scale scores, increases remission, and prevents the onset of clinically significant symptoms of depression in people at risk. Methods: This systematic review searched the PubMed, PsychInfo, Embase, and Cochrane databases from inception to 6 June 2014, using the following terms and strategy: (vitamin B12 or vitamin B9 or folate or folic acid or cobalamin or cyanocobalamin) and (depression or depressive disorder or depressive symptoms) and (randomized controlled trial or RCT). The electronic search was supplemented by manual search. Two independent reviewers assessed all papers retrieved for eligibility and bias, and extracted crude data. Review Manager 5 was used to manage and analyze the data. Results: Two hundred and sixty-nine manuscripts were identified, of which 52 were RCTs and 11 fulfilled criteria for review. We found that the short-term use of vitamins (days to a few weeks) does not contribute to improve depressive symptoms in adults with major depression treated with antidepressants (5 studies, standardized mean difference = −0.12, 95% confidence interval – 95% CI = −0.45, 0.22), but more prolonged consumption (several weeks to years) may decrease the risk of relapse (1 study, odds ratio (OR) = 0.33, 95% CI = 0.12, 0.94) and the onset of clinically significant symptoms in people at risk (2 studies, risk ratio = 0.65, 95% CI = 0.43, 0.98). Conclusions: The number of available trials remains small and heterogeneity between studies high. The results of these meta-analyses suggest that treatment with folate and vitamin B12 does not decrease the severity of depressive symptoms over a short period of time, but may be helpful in the long-term management of special populations.
To compare nutrient intakes between vegetarians and nonvegetarians with similar health practices, and to assess relationships with eating behavior scores from the Three-Factor Eating Questionnaire. Survey. Metropolitan area in western Canada. Subjects (n = 45) were participants in a study comparing subclinical menstrual disturbances between vegetarians and nonvegetarians. To be included, women had to be 20 to 40 years old, be weight stable with a body mass index (BMI; kg/m2) of 18 to 25, be a nonsmoker, exercise 7 hours a week or less, consume one alcoholic drink or less a day, and not be using oral contraceptives. Nonvegetarians (n = 22) ate red meat three times a week or more, and vegetarians (n = 23, 8 vegans and 15 lactovegetarians) had excluded all meat, fish, and poultry for 2 years or more. Nutrient intake assessed by three 3-day diet records; supplement use; body composition; and dietary restraint (conscious limitation of food intake), disinhibition, and hunger assessed by the Three-Factor Eating Questionnaire. Anthropometric variables, nutrient intakes, and eating behavior scores were compared between vegetarians and nonvegetarians using unpaired t tests, and among vegans, lactovegetarians, and nonvegetarians using one-way analysis of variance and Duncan's test. Supplement use was compared using chi 2 analysis. The Pearson correlation coefficient was used to evaluate relationships between variables. Diets of all women adhered closely to current nutrition recommendations. Vegetarians had lower protein and cholesterol intakes and higher percentage of energy as carbohydrate, ratio of polyunsaturated fat to saturated fat (P:S ratio), and fiber intake than nonvegetarians. Vegetarians had lower riboflavin, niacin, vitamin B-12, zinc, and sodium intakes and higher folate, vitamin C, and copper intakes. However, many differences were not apparent between the subgroup of lactovegetarians and nonvegetarians (their P:S ratios and carbohydrate, fiber, riboflavin, folate, vitamin C, and copper intakes were similar). In contrast, differences existed between the lactovegetarian and the vegan subgroups. Supplement use was similar between groups, except for greater vitamin C use by vegetarians. Vegetarians were leaner than nonvegetarians, had lower restraint scores, and had significant associations between restraint and BMI (r = .49; P < .05) and energy per kilogram body weight (r = -.60; P < .01). Current nutrition recommendations can be attained by vegetarians and nonvegetarians alike, but nutrient intakes cannot be inferred from dietary pattern. In this study, the intakes of health-conscious nonvegetarians and lactovegetarians were more similar than the intakes of lactovegetarians and vegans. Vegans' calcium and vitamin B-12 intakes may need attention. Vegetarians' lower restraint scores suggest that they are not at increased risk for eating disorders.
ALSPAC (The Avon Longitudinal Study of Parents and Children, formerly the Avon Longitudinal Study of Pregnancy and Childhood) was specifically designed to determine ways in which the individual’s genotype combines with environmental pressures to influence health and development. To date, there are comprehensive data on approximately 10 000 children and their parents, from early pregnancy until the children are aged between 8 and 9. The study aims to continue to collect detailed data on the children as they go through puberty noting, in particular, changes in anthropometry, attitudes and behaviour, fitness and other cardiovascular risk factors, bone mineralisation, allergic symptoms and mental health. The study started early during pregnancy and collected very detailed data from the mother and her partner before the child was born. This not only provided accurate data on concurrent features, especially medication, symptoms, diet and lifestyle, attitudes and behaviour, social and environmental features, but was unbiased by parental knowledge of any problems that the child might develop. From the time of the child’s birth many different aspects of the child’s environment have been monitored and a wide range of phenotypic data collected. By virtue of being based in one geographic area, linkage to medical and educational records is relatively simple, and hands-on assessments of children and parents using local facilities has the advantage of high quality control. The comprehensiveness of the ALSPAC approach with a total population sample unselected by disease status, and the availability of parental genotypes, provides an adequate sample for statistical analysis and for avoiding spurious results. The study has an open policy in regard to collaboration within strict confidentiality rules.