Healthy Vegetable Oils
Reduced Heart Attack
Risk
Consuming omega-3 fatty
acids found in some
vegetable cooking oils
and fish was associated
with reduced heart
attack risk in a Costa
Rican population study,
and eating omega-6 fatty
acids was linked to
lower blood pressure for
healthy people in an
international study.
The studies were
separately published
respectively in
Circulation: Journal of
the American Heart
Association and
Hypertension: Journal of
the American Heart
Association.
Both omega-3 fatty acids
(alpha-linolenic acids
from plant foods, EPA
and DHA from some fatty
fish) and omega-6 fatty
acids (mainly linoleic
acid) are
polyunsaturated
essential fatty acids
that must be obtained
from food because the
body cannot make them
sufficiently. Omega-3
fatty acids are found in
found in walnuts,
soybean, canola and
flaxseed oils and in
fish such as salmon,
tuna and sardines.
Omega-6 is plentiful in
soybean, safflower,
sunflower, and corn
oils, as well as in
tofu, nuts and seeds.
The American Heart
Association recommends
eating omega-3
containing fish twice a
week and eating your
fats from
polyunsaturated sources
such as nuts, seeds and
vegetable oils.
Replacing saturated and
trans fatty acids with
omega-3 and omega-6
fatty acids may reduce
cardiovascular risks,
according to previous
research.
In the Circulation study
led by Hannia Campos,
Ph.D., intake of omega-3
from vegetable oils was
associated with a 59
percent reduction in
heart attack risk.
Researchers studied
1,819 residents of Costa
Rica who had survived a
first heart attack and
compared them to a
similar group who had
not had a heart attack.
Participants completed a
food and alcohol
frequency questionnaire
and researchers analyzed
body fat samples to
determine their alpha-linolenic
acid content.
Compared to those with
the least amount of
alpha-linolenic acid in
their body fat samples,
those with the highest
levels had a 59 percent
lower heart attack risk
– “a large and
significant reduction.”
“Alpha-linolenic acid
was associated with a
very strong protective
effect, and the
relationship quickly
reached a plateau with
most of the effect
achieved after just a
small intake,” said
Campos, senior lecturer
in the nutrition
department at Harvard
School of Public Health
in Boston, Mass.
These data suggest that
the amount of dietary
alpha-linolenic acid
required to produce this
relationship in this
population study
corresponded to two
teaspoons of soybean oil
or canola oil, half a
teaspoon of flaxseed oil
or six to 10 walnut
halves.
If confirmed by further
research, it might
someday be possible to
reduce the prevalence of
cardiovascular disease
by adding a little of
this essential fatty
acid to the diet in the
many countries where
intake of fish
containing long-chain
omega-3 fatty acids, and
vegetable oils
containing alpha-linolenic
acid is low, as it is in
Costa Rica, Campos
added.
Compared to the United
States, consumption of
vegetable oils
containing omega-3 and
fish is very low in
Costa Rica. Residents
there also tend to eat
tropical white fish,
which is much lower in
long-chain n-3 fatty
acids than the
cold-water species such
as salmon and mackerel
that are commonly eaten
in North America, she
added.
Fortunately, since the
1980s, the Costa Rican
population has decreased
consumption of palm oil,
a vegetable oil that
lacks alpha-linolenic
acid and is high in
saturated fatty acids.
They’ve also increased
consumption of other
vegetable oils –
especially soybean oil –
that are rich in alpha-linolenic
acid, she said. |
