Download The Mediterranean Diet

Vol. 4 No. 3
Summer 2009
The Mediterranean Diet
W
hat is it about diets that
fascinate us? For most,
diets bring the promise
of achieving a desirable state of
health and well-being. Because
this can mean different things
to different people, there are an
enormous number of diets accessible
to consumers. There are diets for
athletes, liquid diets, diets to suit
cultural or social imperatives and
diets for specific allergic or medical
conditions. Common diet names
include the Atkins, Feingold, Pritikin
or Scarsdale diets; there are also the
Shangri-La, Natural Foods, Luteinfree, Cabbage Soup and Grapefruit
diets, as well as the Rastafarian,
Kosher or Buddhist diets. Despite
the vast array of diets available,
there is little doubt that the majority
of dieters seek a diet in order to
lose weight and maintain their new
weight status permanently. Implicit
in the understanding of most
mainstream diets is the notion that
the dieter will feel and be healthier
(although for some dramatic weight
loss diets, this may not be the case).
The one diet that has stood
out above all the rest and has
largely bypassed most nutritional
controversies is the Mediterranean
Diet. It is a bit of a misnomer
because the Mediterranean Sea
contains several very large islands
and is bordered by more than 20
different countries, each with its
own distinct cuisine. In fact, even
Morton Satin ∙ Salt Institute
within the borders of a single
Mediterranean country, such as Italy,
you can find very different diets for
those people living along the coastal
regions, such as the Neapolitans
and those living in, let’s say, Avellino,
less than 25 miles away, nestled in
the heart of the Abruzzi Mountains.
Neapolitans will eat far more fish
and seafood, while residents of the
Abruzzi will consume considerably
more meat, chicken and legumes.
If the diets of the Neapolitans were
compared to their countrymen living
in Bologna, you would think they
lived on different continents.
How then, can the diet in Italy be
compared with those of Morocco,
Egypt, Spain, or Turkey? In fact,
there is no single Mediterranean
diet as such. Our understanding of
the Mediterranean diet is really a
synthesized pastiche of several foods
that are commonly consumed in the
countries surrounded or bordered by
the Mediterranean Sea.
More than any other food, the olive
represents the Mediterranean. The
olives of biblical reference - the
olive branch representing peace and
olive oil used to anoint those who
aspired to greater holiness. Olive
oil is one of the most delectable
eating oils, conferring wonderful
taste and mouthfeel to all foods on
which it is used. Olive oil is also
one of the most nutritious oils,
as it contains a very high level of
monounsaturated fats, most notably
oleic acid and epidemiological
studies suggests that a higher
proportion of monounsaturated fats
in the diet is linked to a reduction in
coronary heart disease risk1. There
is also considerable clinical data
to show that antioxidants in olive
oil can provide additional heart
health benefits such as positive
cholesterol regulation and LDL
cholesterol reduction, and that it
exerts additional anti-inflammatory
and anti-hypertensive effects in
humans2.
Of course, there are many other
foods common to the region - dates,
pomegranates, honey and various
legumes that have been considered
healthful from time immemorial.
Historically, the Mediterranean has
always been depicted as a region of
bountiful fruits, vegetables, cereals
and legumes - and, if high density
protein was sought, then the sea
yielded up its bountiful harvest of
fish.
Fruits, vegetables, cereals, legumes
and fish are the foods typical of the
Mediterranean coastline. In most
of the region’s countries, the inland
production of sheep, goats, and
cattle (where good pastures exist),
together with the dairy products
produced from them, have entered
the diets, mostly as cheeses and
in the eastern Mediterranean, as
yogurt.
The Mediterranean Diet
Each country has its own particular
combination of foods leading to
distinct diets. These diets carried
on from antiquity until well into the
time of the Roman Empire. Slight
changes occurred during the period
of Empire to reflect the broad trade
of foodstuffs that accompanied
it. But the basic focus on cereals,
vegetables, fruits, fish and legumes
continued until the influence of the
invading barbarians from the North
(forest dwelling meat eaters) began
to be more established.
continued from page 1
Here is an example of Castelvetro’s
thoughts:
Of all the salads we eat in spring,
the mixed salad is the best and most
wonderful of all. Take young leaves
of mint, those of garden cress, basil,
lemon balm, the tips of salad burnet,
tarragon, the flowers and tenderest
leaves of borage, the flowers of...
cress, the young shoots of fennel,
leaves of rocket, of sorrel, Rosemary
flowers, some sweet violets, and
the tenderest leaves or the hearts of
lettuce. When these precious herbs
have been picked clean and washed
in several waters, and dried.... with
a clean cloth, they are dressed as
usual, with oil, salt and vinegar.
However, England had far more
ambitious things to think of,
such as building an empire
and extracting the wealth of its
distant colonies to supplement its
own limited resources. England
continued with its humdrum diet
of meat and starchy vegetables
punctured occasionally by
sweets made from the sugar
obtained from its distant tropical
possessions.
The promotion of the benefits of
the Mediterranean-type diet took
place in England during the early
Renaissance, when the Italian,
Giacomo Castelvetro, living in
England wrote his book, “A Brief
Account of the Fruits, Herbs and
Vegetables of Italy.”3 He tried,
without success, to convince the
English to eat more fruits and
vegetables. It is interesting that
recent epidemiological studies
seem to support the notion that
“The Sacred Law of Salads” (i.e.,
raw salads and generous amounts
of olive oil) - originally proposed in
Castelvetro’s book is considered the
first example of customized diets
for cancer prevention based on
individual genetic make-up.4
2
Although concern with the impact
of food upon health continued,
it began to be driven by the new
science of nutrition – the study of
specific nutrients found in various
foods and agricultural products.
Much of the incentive behind this
science came out of the necessity
of keeping sailors and soldiers
alive and in good health during the
extended sea voyages necessary to
expand and maintain the growing
empire. As a result, the focus fell
upon individual foods and their
nutrients rather than diets. Of
particular interest were the foods
that demonstrated anti-scorbutic
properties to prevent scurvy and
those foods, such as “portable
soup”, that would keep up a man’s
strength at the cheapest cost.
The focus on individual nutrients
continued well into the 20th
century as the science of nutrition
developed. There were some notable
exceptions where whole diets
were prescribed to improve health
such as the diet regimes that J. H.
Kellogg instituted at the Battle Creek
Sanitarium. But, by and large, the
focus remained on specific nutrients.
This began to change somewhat
in the 1950s when the nutritionist
Ancel Keys (known for his
development of K-rations during
World War II) noticed that the
cardiovascular performance of
Southern Italians and residents of
the island of Crete were so much
better than their counterparts in
the North of Europe. He attributed
this to their high consumption of
olive oil, salads, vegetables, fruits
and cereals. The fact that, unlike
their counterparts in Northern
Europe and USA, these coastal
Mediterranean residents lived in
regions that had virtually no large
industry and held to a slower-paced
rural lifestyle that included 3-4 hour
lunch-siestas, went almost totally
unrecognized.
At the time, Keys was promoting
the critical role of cholesterol in the
etiology of cardiovascular disease.
The nutrient profile of the generic
Mediterranean diet fit his advocacy
perfectly and he immediately
began promoting its benefits.
Unfortunately, he ignored whatever
did not fit his purposes, namely
lifestyle and one
particular nutrient
- salt.
Olive oil is the
anchor of the
Mediterranean
diet. When drizzled
on salads and
vegetables or white
cheeses such as
mozzarella and
ricotta or grilled
SALT & Health / Summer 2009
The Mediterranean Diet
fish, it adds flavor and a pleasing
mouthfeel. But olive oil by itself
is rather bland and thus is always
accompanied by salt. Even the
descriptions of Castelvetro back
in the 17th century highlight
salt, though it was a very costly
commodity at the time. People’s
preference for salt may vary, but
salt has always accompanied the
consumption of olive oil – salt is
olive oil’s alter ego.
Salt is a critical element of the diet
of Southern Italians, Cretians and all
other residents of the Mediterranean
region. Salt is found everywhere olives cannot be consumed unless
they’re soaked in heavy salt brine
for weeks. The white Greek feta
cheese is cured and stored in salt
brine. Anchovies, capers, olives, cod
and fish roe are all Mediterranean
staples and are all packed in salt.
The breads, pastries and sauces of
the Mediterranean are all high in
salt. Virgin olive oil, so cherished
for making salads, is slightly
bitter because of all the unique
antioxidants it contains, so salt is
especially important for improving
its taste. The famous Greek
taramosalata, is made from salted
codfish roe; tzatziki is made from
salted, fresh cucumbers that are
drained and added to yogurt; North
African baba ghanoush is made
of roasted and mashed aubergine,
blended with tahini, garlic, lemon
juice and lots of salt before being
topped with olive oil and so forth.
Yet, the people who consume all
these highly salted foods of the
Mediterranean are the very ones
that Keys described as having
amongst the best cardiovascular
performance in the world - but he
made no mention of salt.
The Mediterranean diet banner
was picked up and promoted by
Professor Willett and colleagues
at Harvard University as a food
pyramid – an idea that was readily
captured by the media. The name
SALT & Health /Summer 2009
continued from page 2
“Mediterranean Diet” took
root and became entrenched
in our everyday food jargon
without specific reference
to any one Mediterranean
country. In other words the
Mediterranean diet was a
fabrication to fit current
notions of what the diet
should be - tied loosely
to the southern coastal
Mediterranean eating
patterns and claiming
the best cardiovascular
performance.
Again, what appeared to be
left out was the fact that
high levels of salt were
commonly consumed in the
Mediterranean diet.
What was great about the newly
promoted Mediterranean diet was
that it could be so tasty. It was full
of great salads, delicious fruits and
vegetables, mouth-watering pasta
and grilled fish – how could anyone
go wrong with that? What was just
as important was that it encouraged
people to take the time to eat and
savor their foods, not simply to scarf
down as many calories as possible
in the space of five minutes. The
diet, enhanced by mental images
of the beauty of the Mediterranean
coastline and the lithe, bronzed
bodies of Mediterraneans began
to take hold. The number of
restaurants serving Mediterranean
fare exploded.
Not wanting to be left behind, the
National Heart, Lung and Blood
Institute (NHLBI) chose to cash in
on the Mediterranean diet. They
decided to support a study to test
the effects of the Mediterranean diet
on hypertension7. Two issues were
immediately clear; 1) the NHLBI
wanted to see if they could establish
a relationship between diet and
blood pressure, based upon what
was already common knowledge (i.e.
the Mediterranean diet resulted in
good cardiovascular performance
and; 2) that there was little doubt
as to the eventual outcome of the
trial - a fact revealed by the very
name of the study - DASH - Dietary
Approaches to Stop Hypertension.
In fact, only one approach was taken
Blood pressure (BP) is recorded as two
numbers—the systolic pressure (as the
heart beats) over the diastolic pressure
(as the heart relaxes between beats). The
measurement is written with the systolic
on top and the diastolic on bottom. For
example, a blood pressure measurement
of 120/80 mm Hg (millimeters of mercury)
is expressed as “120 over 80.”
continued on page 4
3
The Mediterranean Diet
- the Mediterranean diet. No other
unique diets were tested.
Researchers cobbled together a
simple version of the Mediterranean
diet (the main difference being less
olive oil, as it was not as popular
then) and called it the DASH diet.
(Because of the difference in olive oil
content, the Mediterranean diet is
generally considered superior to the
classic DASH diet�.) Researchers
then compared the DASH diet
to a “typical” American diet. A
diet regime halfway between the
American and Mediterranean diet,
termed the “Fruit and Vegetable” diet
was also used to show a gradation
of response. In order to amplify
the resultant outcome, the patient
population (cohort) was heavily
weighted in favor of those people
that were prone to hypertension
(i.e. 60% were Afro-Americans). The
sodium levels were kept constant
in all three diets at 3,000 mg/day to
approximate what was considered
to be the normal per capita amount
consumed in the USA.
The study showed that the DASH
diet worked - no surprises there - it
was just a matter of determining
how effective it was.
The results of the DASH diet were
very impressive, confirming that the
Mediterranean diet was healthy and
resulted in reduced blood pressure.
The DASH diet reduced systolic BP
by 5.5 mm Hg more and diastolic
BP by 3.0 mm Hg more than the
American diet did. Reductions with
the Fruits and Vegetable diet were
2.8 mm Hg and 1.1 mm Hg – about
half of that obtained with the DASH
diet. What was very impressive was
the 11.4 mm Hg drop in systolic
BP that occurred in hypertensive
patients when they compared the
DASH diet to the American diet.
continued from page 3
DASH trial results
Category
DASH – American
(mm Hg)
DASH – F & V
(mm Hg)
F & V – American
(mm Hg)
Systolic BP
All
Non-hypertensive
Hypertensive
-5.5
-3.5
-11.4
-2.7
-2.7
-4.1
-2.8
-0.8
-7.2
Diastolic BP
All
Non-hypertensive
Hypertensive
-3.0
-2.1
-5.5
-1.9
-1.8
-2.6
-1.1
-0.3
-2.8
most Americans. There was no
doubt that the Mediterranean/DASH
diet could be useful in an American
context, but it might not produce
quite the same cardiovascular
results simply because the lifestyles
were so different from those people
in the Mediterranean coastal areas.
With such an impressive difference
in blood pressure between the
Mediterranean/DASH diet and the
typical American diet, it was a bit of
a surprise when the NHLBI decided
to do another study to add the
dimension of sodium to the diet.
The new trial was called the DASHSodium trial, and again, to ensure
as great a blood pressure response
as possible, a cohort was selected
that was heavily weighted with
hypertension prone people (approx.
60% Afro-Americans).
When the results of the DASH
Sodium trial are examined, it is
immediately apparent that merely
changing to a DASH diet (red line)
has a significantly greater impact
on blood pressure than simply
lowering salt consumption, once
more confirming the benefits of a
Mediterranean-type diet. Dropping
from the normal level of sodium
consumption to the Dietary
Guidelines recommended level
reduced the systolic pressure in
the American diet (blue line) by an
average of 2.1 mm Hg. However,
simply changing from an American
diet to the DASH diet, without any
changes to sodium consumption,
reduced the systolic blood pressure
by 5.9 mm Hg, almost three
times the drop resulting from the
recommended sodium reduction.
The study confirmed that the diet
of Mediterranean residents was
healthier (in terms of BP) than their
northern neighbors and better than
4
SALT & Health / Summer 2009
The Mediterranean Diet
This may partially explain why
Mediterranean people enjoy an
excellent cardiovascular status
despite their high salt consumption.
The one third drop in sodium
consumption is extremely difficult
to achieve and despite major efforts
in the UK, Canada and the USA over
a number of years, it has not been
accomplished - despite the absurd
claims by some advocacy groups
that salt is toxic. The DASH-Sodium
trial results showed that a decent
diet alone was almost three times
better in reducing blood pressure
than a near-impossible to achieve
reduction in salt.
Even the 1/3 reduction in salt
consumption to the American-type
diet - an impossible figure to attain
- only did as well in blood pressure
reduction as the DASH diet by itself
(compare the final blue point to
the first red point). There could be
no doubt that the popular uptake
of the Mediterranean diet could
provide a significant health benefit
to American consumers. The results
further showed that if the DASH
diet were to be combined with a
reduction in salt consumption, there
would be an additional BP drop of
1.3 mm Hg, and a 2/3 drop would
add another 1.7 mm Hg drop. The
problem with these two last results
was that they contradicted the
nature and historical experience
of the Mediterranean diet. Diets
with a high olive oil and vegetable
content require salt to make
them palatable. Cutting the salt
levels by one third would make
the diet far less desirable for
most people and cutting out 2/3
of the salt would make the diets
completely unacceptable. The
net result of this was that fewer
people would consume the DASH
or Mediterranean diets and lose all
the benefits that came from them.
(It should be remembered that the
Mediterranean diet contributes to
far more health benefits than blood
pressure reduction alone.)
SALT & Health /Summer 2009
continued from page 4
A cross-population study on this
subject has not yet been done,
but there is little doubt that
by significantly reducing the
acceptability and uptake of the
DASH/Mediterranean diet, the
average population blood pressure
curve would be shifted to a higher
level. Unfortunately, rather than
using the study results to show the
benefits of a better Mediterraneantype diet, the authors of the study
focused almost exclusively on the
marginal benefits that the salt
reduction added. While the rest
of the medical and nutrition field
agrees that the burden of disease
across the world is due to the
limited consumption of vegetables
and fruits9, there are still many
who remain mired in the salt-blood
pressure argument, oblivious to
the fact that the cardiovascular
performance of high salt-consuming
Mediterraneans10 remains amongst
the best in the world.
More recently, the Mediterranean
diet had been demonstrated to be
useful in reducing a broad range of
cardiovascular disease conditions
and risk factors (obesity, type 2
diabetes, hyperlipidemia, and
hypertension)11 as well as losses in
cognitive functions and Alzheimer’s
diseaese 12. For millennia, this
delicious diet has well-served the
people of the Mediterranean region
and now it is poised to contribute
to the health and well-being of
all those who partake of it. There
are literally dozens of books on
the nutritional aspects of the
Mediterranean diet and dozens more
with a range of excellent recipes
that are easy to make.
So let’s start eating right, or as they
say in Italy, “Buon appetito!”
North African Salad
• 3 tablespoons extra-virgin olive oil, plus
1/4 cup
• 2-3 cloves garlic, crushed and minced
• 1 pound box Israeli couscous (or any tiny
pasta such as ziti)
• 3 cups chicken stock
• 2 lemons, juiced
• 1 lemon, zested
• 1/2 teaspoon salt
• 1/2 teaspoon fresh ground black pepper
• 1 cup chopped fresh basil leaves
• 1/2 cup chopped fresh mint leaves
• 1/3 cup finely chopped Italian parsley
• 1/3 cup dried chopped dates
• 1/4 cup slivered almonds or pistachios,
toasted
In a medium saucepan, warm 3 tablespoons
of the olive oil over medium heat. Add
the garlic and sauté for 1 minute. Add the
couscous and toast until lightly browned,
stirring often, about 5 minutes. Carefully add
the stock, and the juice of 1 lemon and bring
to a boil. Reduce heat and simmer, covered,
until the couscous is tender, but still firm
or al denté to the bite, stirring occasionally,
about 7 to 9 minutes. Drain the couscous.
In a large bowl, toss the cooked couscous
with the remaining olive oil, remaining lemon
juice, zest, salt, and pepper and let cool.
Once the couscous is room temperature,
add the fresh herbs, dried dates, and
almonds/pistachios. Toss well and serve.
Greek Salad
• 1 head green leaf lettuce, torn into
bite-size pieces
• 2 large ripe tomatoes, cut into strips
• 1/2 cucumber, peeled, diced
• 1 cup black olives
• 1/2 red onion, thinly sliced
• 4 small pickled hot peppers
• 1/3 cup feta cheese, crumbled
• 1/2 cup extra virgin olive oil
• 1/4 cup red wine vinegar
• 1/4 teaspoon dried oregano
• Salt and freshly ground black pepper to
taste
Combine lettuce, tomatoes, cucumber,
olives, onion, peppers and cheese in large
bowl.
Whisk olive oil, vinegar and oregano in small
bowl until well blended. Season with salt and
pepper. Pour dressing over salad and toss
well to coat evenly.
5
The Mediterranean Diet
continued from page 5
References
(Endnotes)
1
Keys, A., Menotti, A., Karvonen, M.J., et al. (December 1986). «The diet and 15-year death rate in the seven
countries study,» Am. J. Epidemiol. 124 (6): 903–15.
2 Covas, M.I., (March 2007). “Olive oil and the cardiovascular system”. Pharmacol. Res. 55 (3): 175–86.
3 Castelvetro. G., The Fruits, Herbs and Vegetables of Italy, London, Viking, 1989, translated from the original
published in 1614.
4 Colomer, R., Lupu, R., Papadimitropoulou, A., et al., « Giacomo Castelvetro’s salads. Anti-HER2 oncogene
nutraceuticals since the 17th century?” Clinical and Translational Oncology, 10(1), 30-34, (2008).
5 Willett, W.C., Sacks, F., Trichopoulou, A., Drescher, G., Ferro-Luzzi, A., Helsing, E., and D. Trichopoulos,
“Mediterranean diet pyramid: a cultural model for healthy eating,” American Journal of Clinical Nutrition,
61(supplement), 1402S-1406S, (199).
6 Burros, M., (29 March 1995). “Eating Well”.New York Times, accessed on August 12, 2009 at
http://query.nytimes.com/gst/fullpage.html?res=990CEFD81438F93AA15750C0A963958260&sec=&spon=&pagewanted=all
7 Appel, L.J., Moore, T.J., Obarzanek, E., et al., “A Clinical Trial of the Effects of Dietary Patterns on Blood Pressure,”
NEJM, 336 (16), 1117-1124, (1997).
8 Psaltopoulou, T., Naska, A., Orfanos, P., Trichopoulos, D., Mountokalakis, T., and Trichopoulou, A., “Olive oil, the
Mediterranean diet, and arterial blood pressure: the Greek European Prospective Investigation into Cancer and
Nutrition (EPIC) study,” American Journal of Clinical Nutrition, 80(4), 1012-1018, (2004).
9 Pomerleau et al, “Burden of Disease Attributable to Nutrition in Europe,” Public Health Nutrition, 2002; 6(5):453–
461.
10 C. Leclercq and A. Ferro-Luzzi, “Total and domestic consumption of salt and their determinants in three regions
of Italy,” European Journal of Clinical Nutrition, Mar, 45(3), 151-9, (1991).
11 Martinez-Gonzalez, M.A., Bes-Rastrollo, M., Serra-Majem, L., Lairon, D., Estruch, R., and Trichopoulou, A.,
“Mediterranean food pattern and the primary prevention of chronic disease: recent developments,” Nutrition
Reviews, 67(Supp 1):S111–S116 S111, (2009).
12 Scarmeas, N., Luchsinger, J.A., Schupf, N., Brickman, A.M., Cosentino, S., Tang, M.X., Stern, Y., “Physical Activity,
Diet, and Risk of Alzheimer Disease,” JAMA, 302(6), 627-637. (2009).
We hope you enjoyed this issue of our free quarterly Salt and Health Newsletter
containing timely news and perspective on public health issues associated
with dietary salt. Past issues are posted online at
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