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Acta Clin Croat, Vol. 48, No. 4, 2009 67
Acta Clin Croat 2011; 50:67-77 Review
MEDITERRANEAN DIET IN HEALTHY LIFESTYLE AND
PREVENTION OF STROKE
Vida Demarin, Marijana Lisak and Sandra Morović
University Department of Neurology, Reference Center for Neurovascular Disorders and Headache of the
Ministry of Health and Social Welfare, Republic of Croatia, Sestre milosrdnice University Hospital Center,
Zagreb, Croatia
SUMMARY Several studies demonstrated the beneficial and preventive role of Mediterranean
diet in the occurrence of cardiovascular diseases, chronic neurodegenerative diseases and neoplasms,
obesity and diabetes. In randomized intervention trials, Mediterranean diet improved endothelial
function and significantly reduced waist circumference, plasma glucose, serum insulin and home-
ostasis model assessment score in metabolic syndrome. Several studies support favorable effects of
Mediterranean diet on plasma lipid profile: reduction of total and plasma LDL cholesterol levels,
plasma triglyceride levels, and apo-B and VLDL concentrations, and an increase in plasma HDL
cholesterol levels. is effect is associated with increased plasma antioxidant capacity, improved
endothelial function, reduced insulin resistance, and reduced incidence of the metabolic syndro-
me. e beneficial impact of fish consumption on the risk of cardiovascular diseases is the result
of synergistic effects of nutrients in fish. Fish is considered an excellent source of protein with low
saturated fat, nutritious trace elements, long-chain ω-3 polyunsaturated fatty acids (LCn3PUFAs),
and vitamins D and B. Fish consumption may be inversely associated with ischemic stroke but not
with hemorrhagic stroke because of the potential antiplatelet aggregation property of LCn3PUFAs.
Total stroke risk reduction was statistically significant for fish intake once per week, while the risk
of stroke was lowered by 31% in individuals who ate fish 5 times or more per week. In the elderly,
moderate consumption of tuna/other fish, but not fried fish, was associated with lower prevalence
of subclinical infarcts and white matter abnormalities on MRI examination. Dietary intake of ω-3
fatty acids in a moderate-to-high range does not appear to be associated with reduced plaque, but is
negatively associated with carotid artery intima-media thickness. Greater adherence to Mediterra-
nean diet is associated with significant reduction in overall mortality, mortality from cardiovascular
diseases and stroke, incidence of or mortality from cancer, and incidence of Parkinson’s disease and
Alzheimer’s disease and mild cognitive impairment.
Key words: Stroke – prevention; Diet, Mediterranean; Cardiovascular diseases – prevention
Correspondence to: Marijana Lisak, MD, PhD, University De-
partment of Neurology, Sestre milosrdnice University Hospital
Center, Vinogradska c. 29, HR-1000 Zagreb, Croatia
E-mail: mlisak@kbsm.hr
Received July 7, 2010, accepted September 6, 2010
Introduction
Mediterranean diet is usually consumed among
the populations bordering the Mediterranean Sea,
representing a model of healthy eating, favorable
health status and better quality of life. It was first
described in the 1960s by Angel Keys. Several stud-
ies demonstrated the beneficial and preventive role of
Mediterranean diet on the occurrence of cardiovascu-
lar diseases, chronic neurodegenerative diseases and
neoplasm, obesity and diabetes. Adherence to Medi-
terranean diet is focused on estimating adherence to
the complete Mediterranean diet rather than analyz-
68 Acta Clin Croat, Vol. 50, No. 1, 2011
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
ing individual components of the dietary pattern. Di-
etary scores estimating adherence to Mediterranean
diet are based on the characteristic components of the
traditional Mediterranean diet and associated with
a reduction of overall mortality and morbidity1,2. In
1993, the International Conference on the Diet of
the Mediterranean summarized the key elements of
this diet as follows: abundant plant foods (fruits, veg-
etables, breads, other forms of cereals, beans, nuts,
and seeds); minimally processed, seasonally fresh, and
locally grown foods; fresh fruits as the typical daily
dessert with sweets based on nuts, olive oil, and con-
centrated sugars or honey during feast days; olive oil
as the principal source of dietary lipids; dairy prod-
ucts (mainly cheese and yogurt) in low-to-moderate
amounts; fewer than four eggs per week; red meat
in low frequency and amounts; fish and poultry in
low-to-moderate amounts; wine in low-to-moderate
amounts, generally with meals3-5.
Preventive Role of Mediterranean Diet on Obesity
and Diabetes
Epidemiological evidence for the preventive role
of Mediterranean diet on obesity showed inverse as-
sociation of body mass index (BMI) and Mediterra-
nean diet in a representative Mediterranean Spanish
population and a reduced risk of being obese with
higher adherence to the Mediterranean diet pattern,
independently of whether olive oil was included in
the Mediterranean diet or not6. Longitudinal analy-
sis of Spanish men and women showed that subjects
with high adherence to Mediterranean diet had lower
crude increments of weight during 2 years of follow-
up7. In a randomized intervention 54-month trial,
Mediterranean diet improved endothelial function
and significantly reduced waist circumference, plasma
glucose, serum insulin and homeostasis model assess-
ment (HOMA) score in metabolic syndrome patients,
as epidemiological evidence for the preventive role of
Mediterranean diet in obesity and type 2 diabetes8.
e effectiveness of a Mediterranean lifestyle program
(low-saturated fat diet, stress management training,
exercise and group support, together with smoking
cessation) in reducing cardiovascular risk factors in
postmenopausal women with type 2 diabetes showed
greater improvements in HbA1c, BMI and lipid pro-
file in the intervention group as compared with con-
trol group9. A decrease in several cardiovascular risk
factors such as glycemia, insulinemia or HOMA,
among others, was observed after following a Med-
iterranean-type diet for 3 months10. Improvement in
glucose metabolism was observed after administra-
tion of a Mediterranean-type diet11. e mechanisms
inversely linking Mediterranean diet to excessive
weight include the effect of Mediterranean diet on
satiation (satisfying the appetite that develops during
the course of eating and eventually results in cessa-
tion of eating) and satiety (the sensation that deter-
mines the inter-meal period of fasting). Dietary fibers
induce prolonged mastication while fiber-rich foods
generally contain a large volume of water, which also
increases gastric distention. Gastrointestinal response
to fiber food induces cholecystokinin production and
olive oil promotes postprandial fat oxidation. ese
effects and low degree of energy density (available di-
etary energy per weight-energy content/weight of food
or kJ/g) are favorable features of Mediterranean diet.
e mechanisms inversely linking Mediterranean diet
to type 2 diabetes include preventing obesity, antiox-
idant-rich foods, polyphenol-rich foods, magnesium-
rich foods, moderate alcohol consumption, carbohy-
drate and dietary fiber, and foods rich in unsaturated
fat12. Several studies support the favorable effects of
Mediterranean diet on plasma lipid profile: reduction
of total and plasma LDL cholesterol levels, plasma
triglyceride levels and apo-B and VLDL concentra-
tions, and an increase in plasma HDL cholesterol
levels. is effect is associated with increased plasma
antioxidant capacity, improved endothelial function,
reduced insulin resistance, and reduced incidence of
the metabolic syndrome. Mediterranean diet reduces
the risk of coronary heart disease (CHD), which is not
completely explained by its action on the lipid pro-
file and is also attributable to non-lipid pathways3 -5.
e relationship between dietary glycemic index (GI),
retinal microvasculature changes, and stroke-related
mortality was assessed in the study which consisted of
a population-based cohort. Validated food frequency
questionnaires were used and retinal arteriolar and
venular diameters were measured from photographs.
Mortality data were derived using the National Death
Index. Over 13 years, 3.5% of participants died from
stroke. Increasing GI and decreasing low cereal fiber
(CF) predicted greater risk of stroke death adjusting
Acta Clin Croat, Vol. 50, No. 1, 2011 69
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
for multiple stroke risk factors. Subjects consuming
food in the highest GI tertile and lowest CF tertile
had a 5-fold risk of stroke death. Increasing GI and
decreasing CF were also associated with retinal venu-
lar caliber widening. Adjustment for retinal venular
caliber attenuated stroke death risk associated with
high GI by 50% but did not affect the risk associated
with low CF consumption. High-GI and low-CF di-
ets predict greater stroke mortality and wider retinal
venular caliber. e association between a high-GI
diet and stroke death was partly explained by GI ef-
fects on retinal venular caliber, suggesting that a high-
GI diet may produce deleterious anatomic changes in
the microvasculature13.
Adherence to a Mediterranean Diet-Model of
Healthy Lifestyle
A meta-analysis of adherence to Mediterra-
nean diet and health status included twelve studies
(N=1574299) and analyzed prospectively the associa-
tion between adherence to Mediterranean diet, mor-
tality and incidence of major cardiovascular diseases
and chronic neurodegenerative diseases. Greater ad-
herence to Mediterranean diet was associated with
significant reduction in overall mortality (9%), car-
diovascular disease (CVD) mortality (9%), incidence
of or mortality from cancer (6%), and incidence of
Parkinson’s disease and Alzheimer’s disease (AD)
(13%). Adherence to Mediterranean diet was defined
through scores that estimated conformity of the study
population dietary pattern with the traditional Medi-
terranean dietary pattern2. Several studies showed
inverse association between adherence to Mediterra-
nean diet and the risk of CHD. e Mediterranean
Diet and Incidence and Mortality from Coronary
Heart Disease and Stroke in Women study was per-
formed in 4886 women with no history of CVD and
diabetes (Nurses’ Health Study). Alternate Mediter-
ranean Diet Score (aMED) was computed from self-
reported dietary data collected through administered
food frequency questionnaires. e aMED is focused
on higher consumption of plant foods, including plant
protein, monounsaturated fat and fish, and lower con-
sumption of animal products and saturated fat. e
possible aMED score range was 0-9, with a higher
score representing closer resemblance to Mediter-
ranean diet. Results showed 2391 incident cases of
CHD (1597 nonfatal and 794 fatal) and 1763 incident
cases of stroke (959 ischemic, 329 hemorrhagic and
475 unclassified). Of all strokes, 1480 were nonfatal
and 283 fatal. ere were 1077 CVD deaths (fatal
CHD and stroke combined)12.
Mediterranean Diet and the Risk of Alzheimer’s
Disease and Mild Cognitive Impairment
Higher adherence to a Mediterranean-type diet
and higher level of physical activity have been inde-
pendently associated with a reduced risk of AD. In a
prospective cohort study (N=1880) including subjects
without dementia with diet and physical activity infor-
mation available, adherence to a Mediterranean-type
diet (scale of 0-9: low, middle, or high) and physical
activity (sum of weekly participation in various physi-
cal activities: light, moderate, or vigorous; no physical
activity, some, or much) were evaluated in separate and
in combination. A total of 282 incident AD cases oc-
curred during a mean of 5.4 years of follow-up. Com-
pared with individuals neither adhering to the diet nor
participating in physical activity (low diet score and
no physical activity; absolute AD risk of 19%), those
both adhering to the diet and participating in physi-
cal activity (high diet score and high physical activity)
had a lower risk of AD (absolute AD risk of 12%).
Both physical activity and diet were significantly as-
sociated with AD incidence when considered simul-
taneously in the same model. Belonging to the middle
diet adherence tertile was associated with a 2%-14%
risk reduction, while belonging to the highest diet ad-
herence tertile was associated with a 32%-40% risk
reduction. Similarly, compared with individuals with
no physical activity, individuals reporting some physi-
cal activity had the risk of AD lower by 25%-38%,
while individuals reporting much physical activity
had the risk of AD lower by 33%-48%. Concerning
the Mediterranean-type diet adherence, compared
with low diet score, the hazard ratio (HR) for middle
diet score was 0.98 and for high diet score 0.60. Con-
cerning physical activity, compared with no physical
activity, HR was 0.75 for some physical activity and
0.67 for much physical activity14. Higher adherence to
Mediterranean diet may protect from AD and mild
cognitive impairment. A community study in New
York investigated the association between adherence
to Mediterranean diet (scale 0-9: higher score, higher
70 Acta Clin Croat, Vol. 50, No. 1, 2011
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
adherence), incidence of mild cognitive impairment
and progression from mild cognitive impairment to
AD. e study included 1393 cognitively normal
subjects; 275 of them developed mild cognitive im-
pairment during 4.5-year follow-up. Compared to
subjects in the lowest Mediterranean diet adherence
tertile, subjects in the middle Mediterranean diet ad-
herence tertile had the risk of developing mild cog-
nitive impairment lower by 17%, while those in the
highest Mediterranean diet adherence tertile had the
risk of developing mild cognitive impairment lower
by 28%. ere were 482 subjects with mild cogni-
tive impairment, of which 106 developed AD during
4.3-year follow-up. Compared to subjects in the low-
est Mediterranean diet adherence tertile, subjects in
the middle Mediterranean diet adherence tertile had
the risk of developing AD lower by 45%, while those
in the highest Mediterranean diet adherence tertile
had the risk of developing AD lower by 48%. Higher
adherence to Mediterranean diet is associated with a
trend of a reduced risk of developing mild cognitive
impairment and of its conversion to AD15.
Fish Consumption Can Reduce the Risk of
Cardiovascular Diseases and Stroke
e long-chain ω-3 polyunsaturated fatty acids
(LCn3PUFAs), eicosapentaenoic acid (EPA), do-
cosapentaenoic acid (DPA) and docosahexaenoic acid
(DHA) in fish are the key nutrients responsible for
the cardioprotective benefits and CVD prevention.
e beneficial effects of fish consumption on the risk
of CVD include the synergistic effects of nutrients in
fish, and the integrative effects may reflect the inter-
actions of nutrients. Fish is considered an excellent
source of proteins with low saturated fat (taurine,
arginine and glutamine, known to regulate cardiovas-
cular function); some nutritious trace elements (sele-
nium and calcium, which may directly or indirectly
provide cardiovascular benefits, alone or in combi-
nation with LCn3PUFAs and vitamins (vitamins D
and B). Interactions between LCn3PUFAs and other
nutrients including nutritious trace elements and vita-
mins and amino acids are important in reducing the
risk of CVD.
e overall favorable effect is observed on lipid
profiles, threshold for arrhythmias, platelet activity,
inflammation and endothelial function, atheroscle-
rosis and hypertension16. Consumption of whole fish
would have greater benefits than fish oil supplements,
calling for caution on recommending taking fish oil
supplements instead of consuming whole fish. e
American Heart Association recommends eating fish
(particularly fatty fish) at least 2 times a week17. Fish
consumption may be inversely associated with isch-
emic stroke but not with hemorrhagic stroke because
of the potential antiplatelet aggregation property of
LCn3PUFAs. A meta-analysis of 8 independent pro-
spective cohort studies, which included 200 575 sub-
jects and 3491 stroke events showed that individuals
with higher fish intake had a lower total risk of stroke
compared with those never consuming fish or eating
fish less than once a month. e reduction in the total
risk of stroke was statistically significant for fish intake
once per week; for individuals who ate fish 5 times or
more per week, the risk of stroke was lower by 31%.
e risk of ischemic stroke was significantly reduced
by eating fish twice a month. e observation of the
high incidence of hemorrhage in Eskimos, who con-
sume large amounts of fish, has raised concerns about
the possible adverse effects of high fish intake on the
risk of hemorrhagic stroke. Further studies are needed
to investigate fish or LCn3PUFA intake in relation to
the risk of hemorrhagic stroke. e types of fish ap-
pear to be less important as long as one takes certain
amounts of LCn3PUFAs. Different types of fish may
exert different effects if we consider fish as a nutrient
package. e type of fish is important with respect to
investigating contaminants in fish.
Dietary Intake of Fish and Cooking Methods
e benefits from different cooking methods have
not yet been studied thoroughly. It has been suggested
that broiled and baked fish, but not fried fish and fish
sandwiches, are associated with a lower incidence of
atrial fibrillation and ischemic heart disease. Studies
suggest that vascular benefits of fish consumption may
be altered by preparation methods. Frying may modi-
fy the lipid profile through a decrease in the ω-3/ω-6
fatty acid ratio18. In the Cardiovascular Health Study,
3660 participants aged over 65 underwent an MRI
scan to evaluate fish consumption and risk of subclini-
cal brain abnormalities on MRI in older adults. In the
elderly, modest consumption of tuna/other fish, but
not fried fish, was associated with a lower prevalence
Acta Clin Croat, Vol. 50, No. 1, 2011 71
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
of subclinical infarcts and white matter abnormalities
on MRI examination. Tuna or other fish consump-
tion was also associated with a trend toward a lower
incidence of subclinical infarcts and with better white
matter grade. No significant associations were found
between fried fish consumption and any subclinical
brain abnormalities. Dietary intake of fish with higher
eicosapentaenoic acid and docosahexaenoic acid con-
tent, and not fried fish intake, may have clinically im-
portant health benefits. After adjustment for multiple
risk factors, the risk of having one or more prevalent
subclinical infarcts was lower among those consum-
ing tuna or other fish ≥3 times per week compared to
<1 per month. e risk reduction in those consuming
tuna/other fish ≥3 times per week was 0.56 compared
to <1 per month. Each serving/week of tuna/other fish
was associated with a trend toward 11% lower risk re-
duction of any incident subclinical infarct and 12%
lower risk reduction of each additional multiple in-
farct19. According to the Genetics of Coronary Artery
Disease in Alaska Natives Study, consumption of ω-3
fatty acids is not associated with a reduction in ca-
rotid atherosclerosis. e study included a population-
based sample that underwent ultrasound assessment
of carotid atherosclerosis. Diet was assessed by a food
frequency questionnaire. e intima-media thickness
(IMT) of the distal wall of distal common carotid ar-
teries and plaque score (number of segments contain-
ing plaque) were assessed. e mean consumption of
total ω-3 fatty acids was 4.76 g/day in those without
and 5.07 g/day in those with plaque. e presence and
extent of plaque were unrelated to the intake of C20-
22 ω-3 fatty acids or total ω-3 fatty acids. e odds of
plaque rose significantly with quartiles of the palm-
itic and stearic acid intake. e extent of plaque (or
plaque score) was also associated with a higher per-
centage intake of palmitic acid. IMT was negatively
associated with grams of C20-22 ω-3 fatty acids, total
ω-3, palmitate and stearate consumed. Dietary intake
of ω-3 fatty acids in a moderate-to-high range does
not appear to be associated with reduced plaque, but
is negatively associated with IMT. e presence and
extent of carotid atherosclerosis among Eskimos is
higher with increasing consumption of saturated fat-
ty acids. ere were no significant differences in the
prevalence of atherosclerotic plaque or mean plaque
score with increasing quartiles of dietary intake of ei-
ther total ω-3 fatty acids or C20-22 ω-3 fatty acids.
When analyzed as percentage of total fat intake, C20-
22 consumption and total ω-3 fatty acid consumption
were not related to average IMT. When the analyses
were adjusted for age and sex, positive associations
were observed between the percentage of fat intake
from palmitic acid or stearic acid and the presence
of plaque and plaque score. When analyzed as daily
intake in grams, higher quartiles of intake of either
palmitate or stearate were associated with significantly
higher average IMT, when adjusted for age and sex20.
Tea Consumption and the Risk of Stroke
A meta-analysis of green and black tea consump-
tion and the risk of stroke included data from 9 stud-
ies involving 4378 strokes in 194 965 individuals. e
main outcome assessed was the occurrence of fatal or
nonfatal stroke. e summary effect associated with
consumption of ≥3 cups of tea (green or black) per day
was calculated. Regardless of their country of origin,
individuals consuming ≥3 cups of tea per day had by
21% lower risk of stroke than those consuming less then
1 cup per day (absolute risk reduction 0.79; CI 0.73-
0.85). e results are consistent across green and black
tea. e types of catechins differ between green and
black tea; their total amounts are comparable because
both black and green tea are derived from the same
source: the catechins produced within the Camelia sin-
ensis plant and both have demonstrated effects on vas-
cular function. Both types of tea have been shown to
reduce blood pressure in stroke prone hypertensive rats
at doses equivalent to 1 L per day in humans. Popula-
tion-based analyses do not support a generalized neg-
ative association between tea consumption and blood
pressure. Catechin ingestion blocked the increase in
serum nitric oxide concentration in rats after reperfu-
sion and tea had evident effect on endothelial func-
tion. eanine is readily bioavailable from both green
and black tea, crosses the blood-brain barrier, and has
effects on brain function; it contains the glutamate
molecule and it might reduce the glutamate-related
endothelial damage. Studies of middle cerebral artery
occlusion in mice demonstrated the neuroprotective
effect of Υ-glutamylethylamide (theanine) at dosages
of 0.5 and 1.0 mg/kg reducing the size of cerebral in-
farct. Regular tea consumption, instead of preventing
overt stroke, may reduce the post-ischemic damage to
72 Acta Clin Croat, Vol. 50, No. 1, 2011
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
a level that results in subclinical ischemia or hidden
strokes. is would result in the diagnosis of stroke
only in individuals with more extensive post-ischemic
damage or greater stroke volume21. ree-City Study
showed tea consumption to be inversely associated
with carotid plaques in women. Results were tested
for replication in younger population sample, in the
EVA Study. Atherosclerotic plaques in extracranial
carotid arteries and common carotid artery (CCA)
IMT were measured. In the ree-City Study, in-
creasing daily tea consumption was associated with a
lower prevalence of carotid plaques in women: 44.0%
in women drinking no tea, 42.5% in those drinking 1
to 2 cups per day, and 33.7% in women drinking more
then 3 cups per day. is association was independent
of age, center, major vascular risk factors, educational
level, and dietary habits. ere was no association of
tea consumption with carotid plaques in men, or with
CCA-IMT in both sexes. In the EVA study, the ca-
rotid plaque frequency was 18.8% in women drink-
ing no tea, 18.5% in those taking 1 to 2 cups per day,
8.9% in those taking 3 cups per day. Carotid plaques
were less frequent with increasing tea consumption in
women22. Coffee and tea consumption could poten-
tially reduce the risk of stroke because these beverages
have antioxidant properties, and coffee may improve
insulin sensitivity. Data from the Alpha-Tocopherol,
Beta-Carotene Cancer Prevention Study included 26
556 male Finnish smokers aged 50-69 years, without
a history of stroke. Coffee and tea consumption was
assessed at baseline. After adjustment for age and car-
diovascular risk factors, consumption both of coffee
and tea was statistically significantly inversely asso-
ciated with the risk of cerebral infarction but not of
intracerebral or subarachnoid hemorrhage. e mul-
tivariate risk reduction of cerebral infarction for men
in the highest category of coffee consumption (≥8
cups per day) was 0.77 compared with those in the
lowest category (<2 cups per day). e corresponding
risk reduction comparing men in the highest category
of tea consumption (≥2 cups per day) with those in
the lowest category (non-drinkers) was 0.79. ese
results suggest that high consumption of coffee and
tea may reduce the risk of cerebral infarction among
men, independently of the known cardiovascular risk
factors. e risk reduction of cerebral infarction for
men in the highest compared with the lowest cate-
gory of consumption was 0.77 for coffee and 0.79 for
tea. Additional adjustment for consumption of fruits,
vegetables, fish, and total fat did not appreciably alter
the results for coffee or tea. Regression analysis dem-
onstrated a dose-response relationship between coffee
consumption and the risk of cerebral infarction23.
Whole-Grain Intake and the Importance of
Glycemic Index in Cholesterol Management
In the Insulin Resistance Atherosclerosis Study,
whole-grain intake and carotid artery atherosclerosis
were evaluated in a multiethnic cohort. Association
of whole-grain intake with carotid IMT and pro-
gression was evaluated by color Doppler flow imag-
ing (CDFI). Baseline whole-grain intake estimate
was based on the intake of dark breads, cooked cere-
als and high-fiber cereals as assessed with a validated
food-frequency questionnaire; median whole-grain
intake was 0.79 servings per day. Whole-grain intake
was inversely associated with CCA IMT and IMT
progression. is association was less significant for
ICA IMT and not significant for ICA IMT progres-
sion. e relation between whole-grain intake and
CCA IMT remained significant after adjustment
for mediating pathways (lipids, adiposity and insulin
resistance), nutrient constituents, and the principal
components-derived healthy dietary pattern. Whole-
grain intake was inversely associated with CCA IMT
and this relation was not attributable to individual risk
intermediates, single nutrient constituents, or larger
dietary patterns24.
Vitamin C is Associated with a Lower Risk of Stroke
A 3-year intervention study showed the vitamin
C consumption to be associated with less progres-
sion in carotid IMT in elderly men. Carotid artery
IMT and diet were assessed in elderly men. Men were
randomly assigned to 1 of 4 groups: dietary interven-
tion, ω-3 supplementation, both, or neither. Results
previously showed that omega-3 supplementation did
not influence the IMT, thus the dietary interven-
tion and no dietary intervention groups were pooled.
e dietary intervention group had less progression
in carotid IMT compared with controls. is group
increased their daily vitamin C intake and intake of
fruit, berries and vegetables. Increased intake of vita-
min C and of fruit and berries was inversely associated
Acta Clin Croat, Vol. 50, No. 1, 2011 73
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
with IMT progression. Multivariate linear regression
analysis showed that increased intakes of vitamin C
and of fruit and berries were associated with less IMT
progression in the intervention group and in the to-
tal study population, after adjustment for consump-
tion of dietary cholesterol, cheese, saturated fat and
group assignment. Vitamin C containing foods may
protect against the progression of carotid atheroscle-
rosis in elderly men25. Fruits and vegetables, and foods
rich in flavonoids and antioxidants have been associ-
ated with a lower risk of stroke, CHD, and markers of
inflammation and oxidative stress in adults. Markers
of inflammation and oxidative stress are predictors of
the CHD risk; however, it is unknown whether these
markers are related to dietary flavonoid and antioxi-
dant intake in youth. Correlation analyses evaluated
the relation of the intakes of fruit and vegetables,
antioxidants, folate and flavonoids with markers of
inflammation (C-reactive protein, interleukin-6, tu-
mor necrosis factor-α and 15-keto-dihydro-PGF2α
metabolite) and oxidative stress (urinary 8-iso pros-
taglandin F2α and F2-isoprostane). e association
of nutrient intake and markers of inflammation and
oxidative stress was inversely related to some markers
of inflammation, including CRP and IL-6, and oxi-
dative stress (F2-isoprostane). e beneficial effects of
fruit and vegetable intake on markers of inflammation
and oxidative stress are already present by early ado-
lescence, thus the results of this study support Dietary
Guidelines for Americans to consume 5 or more serv-
ings per day of fruits and vegetables for cardiovascular
health26.
e Importance of Chocolate in Brain Health
Chocolate has always been considered distinctive
among foods. It has always held a particular place in
human society, from its historical use as a divine es-
sence up to its status today as the food of pleasure.
Chocolate is not classified as part of any of the four
fundamental plant groups of food (whole grains, veg-
etables, fruit, and legumes). It is rather defined as “a
paste, powder, syrup or bar, made from cacao seeds
that have been roasted and ground”. It contains nutri-
ents and provides nourishment, thus fitting the defi-
nition of a food. It contains approximately 50% of fat
and close to 50% of carbohydrate; this combination of
nutrients results in a powerful effect whereby all brain
chemicals (serotonin, dopamine, and opiate peptides)
are positioned at optimal levels for positive mood and
euphoric feelings. Chocolate also contains more than
400 distinct flavor compounds (more than twice as
many as any other food)27.
Chocolate and Heart
In various controlled studies, consumers of dark
chocolate showed benefits such as lowered blood pres-
sure, reduced oxidation of low-density lipoproteins
and reduced platelet aggregation. ese findings are
attributed to the presence in cocoa of a certain group
of flavonoids including epicatechin, catechin, and
procyanidins. ese substances have pronounced an-
tioxidative properties to which the beneficial effects
are being ascribed. Stimulation of nitric oxide produc-
tion is another possible route for their effects, and they
have also been suggested to modulate certain cell sig-
naling pathways and gene expression, and to influence
cell membrane properties and receptor function. e
positive effects seem to be limited to dark chocolate,
the milk in milk chocolate apparently interfering with
flavonoid absorption in the gut28.
Environmental Vascular Risk Factors: New
Perspectives for Stroke Prevention
In addition to traditional and non-traditional vas-
cular risk factors, a number of environmental risk fac-
tors for stroke have been identified in the last decade,
i.e. lower education and poor socioeconomic status as
surrogates for exposure to traditional high-risk behav-
iors such as smoking, poor nutrition, lack of prenatal
control, absence of preventive medical and dental care,
and noncompliance with the treatment of conditions
such as hypertension; depression, stress and affective
disorders; obstructive sleep apnea; passive smoking
and environmental pollution; infections, in particular
periodontal diseases that increase C-reactive protein
(CRP); raised BMI (obesity); lack of exercise; and
diet29,30. Protective diets include Mediterranean diet, as
well as probiotic bacteria in yogurt and dairy products.
Attention should be paid to the patient’s environment
looking for modifiable factors. e effects of clean en-
vironmental air and water, adequate diet and appro-
priate nutrition, healthy teeth, exercise, and refreshing
sleep in the prevention of stroke and CVD appear to
be quite compelling. Although some of these modifi-
74 Acta Clin Croat, Vol. 50, No. 1, 2011
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
able risk factors lack evidence-based information, ju-
dicious clinical sense should be used to counteract the
potentially damaging effects of adverse environmental
vascular risk factors31. Dietary fat intake is associated
with the risk of CHD and ischemic stroke. As part
of the prospective Northern Manhattan Study, 3183
stroke free community residents underwent evaluation
of their medical history and had their diet assessed by
a food-frequency survey. During the study, 142 isch-
emic strokes occurred and after adjusting for potential
confounders, the risk of ischemic stroke was higher in
the upper quintile of total fat intake compared to the
lowest quintile. Total fat intake >65 g was associated
with an increased risk of ischemic stroke. e results
suggest that increased daily total fat intake, especially
above 65 g, significantly increases the risk of ischemic
stroke. e ischemic stroke risk for those in the high-
est quintile of fat intake was higher than for those in
the lowest quintile, both in unadjusted analyses and
after adjusting for age, race/ethnicity, sex, education,
hypertension, diabetes, coronary artery disease, mod-
erate alcohol consumption, current smoking, previous
smoking, any physical activity and BMI. Similarly,
when fat as a percentage of total daily calories was
examined, those who obtained 45% or more of their
calories from fat showed a trend toward an increased
risk of ischemic stroke32. Fast food options have be-
come a quickly growing and universal phenomenon
offering a quick and inexpensive meal high in fat and
salt, and rarely providing fruit, vegetables or whole
grains. Fast food restaurants tend to cluster in neigh-
borhoods that are more economically disadvantaged
and in areas with high proportions of minority resi-
dents. Neighborhood disadvantage has been linked to
stroke risk. Accessibility to fast food restaurants may
be one pathway by which neighborhood disadvantage
contributes to atherosclerosis. Neighborhoods that
have high fast food restaurant densities have less op-
tions for healthy eating. If fast food restaurant den-
sity is associated with stroke risk, then appropriate
public health interventions in specific neighborhoods
can be suggested. Other risk factors that go beyond
traditional biologic and social risk factors may poten-
tially contribute risk for common, severe diseases such
as stroke. e association of the density of fast food
restaurants with ischemic stroke in neighborhoods
was evaluated as part of a population based study in
South Texas. ere were 1247 completed ischemic
strokes during 3 years and 262 fast food restaurants
located in the area. e association of fast food res-
taurants with stroke was significant. e association
suggested that the risk of stroke in the neighborhood
increased by 1% for every fast food restaurant. ere
was a significant association between fast food restau-
rants and stroke risk in neighborhoods in this com-
munity based study33. e combined effect of health
behaviors and risk of first-ever stroke was assessed in
20 040 men and women during 11-year follow-up in
Norfolk cohort of the European Prospective Investi-
gation of Cancer. e potential combined impact of 4
health behaviors on the incidence of stroke was fol-
lowed up over 14 years in men and women aged 40-79
with no known stroke or myocardial infarction, liv-
ing in the general community. Participants scored one
point for each health behavior: current non-smoking,
physically not inactive, moderate alcohol intake (1-14
units a week), and plasma concentration of vitamin
C ≥50 µmol/L, indicating fruit and vegetable intake
of at least five servings a day, for a total score ranging
from 0 to 4. Four health behaviors combined predict
more than a two-fold difference in the incidence of
stroke in men and women. ere were 599 incident
strokes during a 11.5-year follow-up period. After ad-
justment for age, sex, BMI, systolic blood pressure,
cholesterol concentration, history of diabetes and as-
pirin use, and social class, compared with people with
the four health behaviors, the relative risk of stroke
in men and women was 1.15 (95% CI 0.89-1.49) for
three health behaviors, 1.58 for two, 2.18 for one, and
2.31 for none (P<0.001 for trend). e relations were
consistent in subgroups stratified by sex, age, BMI
and social class, and after exclusion of deaths within
two years34. e preventive role of Mediterranean diet
on the occurrence of cardiovascular events and stroke
has been well established in randomized clinical tri-
als. Some authors even suggest taking certain foods
as treatment for various neurological and psychologi-
cal disorders such as dementia, headache, depression,
neurodegenerative disorders and schizophrenia, as
well as for other health problems such as carcinoma.
Different nutrients found in different foods have a
strong impact on our memory, concentration, think-
ing processes and emotional state, but the most wanted
on the brain-smart grocery list include salmon, virgin
Acta Clin Croat, Vol. 50, No. 1, 2011 75
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
olive oil, romaine lettuce, dark chocolate (at least 60%
of cocoa), hazelnuts and raspberries. It is scientifically
proven that the food we consume greatly affects our
body and the health of our brain, thus Mediterranean
diet is the best way to feed your neurons35.
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Acta Clin Croat, Vol. 50, No. 1, 2011 77
Vida Demarin, Marijana Lisak and Sandra Morović Mediterranean diet in prevention of stroke
Sažetak
MEDITERANSKA PREHRANA ZA ZDRAV NAČIN ŽIVOTA I PREVENCIJU MOŽDANOG UDARA
V. Demarin, M. Lisak i S. Morović
Brojna ispitivanja su potvrdila blagotvoran učinak i preventivnu ulogu mediteranske prehrane na pojavnost kardiova-
skularnih bolesti, kroničnih neurodegenerativnih bolesti i neoplazma, pretilosti i dijabetesa. U randomiziranim kliničkim
pokusima mediteranska prehrana je poboljšala endotelijsku funkciju i značajno smanjila opseg struka, razinu serumske
glukoze i inzulina te procjenu modela homeostaze u metaboličnom sindromu. Ispitivanja podupiru pozitivan učinak medi-
teranske prehrane na sniženje ukupnog kolesterola i LDL kolesterola, na razinu triglicerida i koncentraciju apo-B i VLDL
čestica, te na povećanje razine HDL kolesterola. Učinak je povezan s povećanim kapacitetom antioksidansa u serumu, s
poboljšanom endotelijskom funkcijom, smanjenjem inzulinske rezistencije i sniženom incidencijom metaboličnog sin-
droma. Povoljni učinci konzumiranja ribe na kardiovaskularne bolesti nastaju zbog sinergističnog i integrativnog učinka
svih hranjivih sastojaka ribe. Riba je izvrstan izvor proteina s nezasićenim masnim kiselinama, hranjivih elemenata u
tragovima, ω-3 nezasićenih masnih kiselina te vitamina D i B. Konzumiranje ribe može biti obrnuto povezano s ishemič-
nim moždanim udarom, ali ne i s hemoragijskim moždanim udarom, zbog potencijalnih antiagregacijskih svojstava ω-3
nezasićenih masnih kiselina. Smanjenje ukupnog rizika za moždani udar zabilježeno je pri konzumiranju ribe jedanput
na tjedan. Više od pet ribljih obroka na tjedan umanjuje rizik od moždanog udara za 31%. U starijih osoba je uz umjereno
konzumiranje tune ili druge ribe koja nije pržena zabilježena niža učestalost subkliničkih infarkta i abnormalnosti bijele
tvari na MR snimkama mozga. Unos ω-3 nezasićenih masnih kiselina u umjerenim količinama ne pokazuje povezanost sa
smanjenjem arterijskog plaka, ali je negativno povezan s debljinom intime-medije karotidnih arterija. Povećana sklonost
mediteranskoj prehrani povezana je sa značajnim sniženjem ukupne smrtnosti, smrtnosti od kardiovaskularnih bolesti,
moždanog udara i neoplazma, te sa smanjenom incidencijom Parkinsonove i Alzheimerove bolesti i blagog kognitivnog
poremećaja.
Ključne riječi: Moždani udar – prevencija; Dijeta, mediteranska; Kardiovaskularne bolesti – prevencija
