body mass index. Although there are relatively few
studies of Mediterranean diets as weight-reduction reg-
imens, a research team at the Harvard School of Public
Health reported in 2007 that a Mediterranean-style diet
is an effective approach to weight loss for many people.
A major reason for its effectiveness is the wide variety
of enjoyable foods permitted on the diet combined with
a rich tradition of ethnic recipes making use of these
foods—which makes it easier and more pleasant for
people to stay on the diet for long periods of time.
Precautions
People who are making any major change in their
dietary pattern in general should always consult their
physician first. In addition, people who are taking
monoamine oxidase inhibitors (MAOIs) for the treat-
ment of depression should check with their doctor, as
these drugs interact with a chemical called tyramine to
cause sudden increases in blood pressure. Tyramine is
found in red wines, particularly aged wines like
Chianti, and in aged cheeses.
People using a Mediterranean diet for weight
reduction should watch portion size and monitor
their consumption of olive oil, cheese, and yogurt,
which are high in calories. Dieters may wish to con-
sider switching to low-fat cheeses and yogurts.
Because olive oil is a staple of Mediterranean
diets, consumers should purchase it from reliable sour-
ces. The safety of olive oil is not ordinarily a concern in
North America; however, samples of olive oils sold in
Europe and North Africa are sometimes found to be
contaminated by mycotoxins (toxins produced by
molds and fungi that grow on olives and other fruits).
Some mycotoxins do not have any known effects on
humans, but aflatoxin, which has been found in olive
oil, is a powerful carcinogen and has been implicated
in livercancer.
Risks
There are no major risks associated with following
a traditional Mediterranean diet for people who have
consulted a physician beforehand if they intend to use
the diet as a weight-loss regimen. Health crises caused
by food interactions with MAOIs are uncommon but
can be fatal (about 90 deaths over a 40-year period).
The risk of cancer or any other disease from
aflatoxin-contaminated olive oil is minimal in the
United States and Canada.
Research and general acceptance
Mediterranean diets have been the subject of more
medical research since the 1960s than any other
regional or ethnic diet. Interest in Mediterranean
diets has been high because nutritional research in
general has moved away from curing deficiency dis-
eases in the direction of preventive health care.The Seven Countries Study
The results from the Seven Countries study were
published in book form in 1980. The research teams
found that Japanese and Greek men had far lower
rates of cardiovascular disease than men from the
other five other countries, with the Greek subjects
from the island of Crete having the lowest rate of all.
Although the study and thirty years of follow-up
reports showed that the relationship among heart dis-
ease, body mass, weight, andobesityis complex, the
Seven Countries research also showed that the type of
fat in the diet is more important than the amount, and
that the use of monounsaturated fats—particularly
olive oil—is correlated with a lower risk of heart attack
and stroke. The twenty-year follow-up report indicated
that 81% of the difference in coronary deaths among
the seven countries could be explained by differences in
the average intake of saturated fatty acids.
A detailed description of the Seven Countries
study, the research that preceded it, and an overview
of its findings can be found online on the website of
the University of Minnesota School of Public Health,
Division of Epidemiology and Community Health, at
<http://www.epi.umn.edu/about/7countries/index.shtm>.The Lyon Diet Heart Study
The Lyon Diet Heart Study was the first clinical
trial to demonstrate the beneficial effects of a Medi-
terranean-type diet. Begun in 1995, it was a major
investigation of the effectiveness of a modified Cretan
diet in preventing recurrent heart attacks. The subjects
were a group of 605 Frenchmen under 70 years of age
who had been treated in the previous 6 months for aQUESTIONS TO ASK YOUR
DOCTOR Would you recommend a Mediterranean type of
diet for general wellness as well as weight
control?
Have any of your other patients tried a
Mediterranean diet? Did they enjoy it?
Would you recommend the modified version of
the Cretan diet used in the Lyon Diet Heart
Study?Mediterranean diet