Heart failure risk lower in postmenopausal
women who often eat baked and broiled fish
The risk of developing heart failure was lower for
postmenopausal women who frequently ate baked or broiled fish, but higher for
those who ate more fried fish, in a study reported in Circulation: Heart Failure,
an American Heart Association journal. In a large-scale analysis, women
who ate the most baked/broiled fish (five or more servings/week) had a 30 percent
lower risk of heart failure compared to women who seldom ate it (less than one
serving/month). Previous research has found that fatty acids (omega-3) in
fish - EPA, DHA and ALA - may lower risk of cardiovascular disease by decreasing
inflammation, resisting oxidative stress and improving blood pressure, cardiac
and blood vessel function. This study showed that the type of fish and cooking
method may affect heart failure risk. The researchers found that dark fish (salmon,
mackerel and bluefish) were associated with a significantly greater risk reduction
than either tuna or white fish (sole, snapper and cod). In a similar analysis,
eating fried fish was associated with increased heart failure risk. Even one serving
a week was associated with a 48 percent higher heart failure risk. "Not
all fish are equal, and how you prepare it really matters," said Donald Lloyd-Jones,
M.D., Sc.M., senior author of the study. "When you fry fish, you not only
lose a lot of the benefits, you likely add some things related to the cooking
process that are harmful." Other research has shown that frying increases
the trans fatty acid (TFA) content of foods, which is associated with increasing
risk for heart disease. In this study, however, the researchers did not find an
association between TFA and heart failure risk. Lloyd-Jones and his team
examined self-reported dietary data from 84,493 postmenopausal women in the Women's
Health Initiative Observational Study. They then divided study participants based
on the frequency and type of fish consumption. Two groups of fish intake were
defined: baked/broiled fish or fried fish. The baked/broiled fish group consisted
of canned tuna, tuna salad, tuna casserole, white fish (broiled or baked), dark
fish (broiled or baked) and shellfish (not fried). The fried fish group consisted
of fried fish, fish sandwich and fried shellfish. They conducted their analysis
based on data from 1991 through August 2008. During an average follow-up of 10
years, 1,858 cases of heart failure occurred. Most participants (85 percent)
were Caucasian, 7 percent African-American and 3 percent Hispanic. Their average
age was 63 at baseline. Participants whose diets included more baked/broiled
fish tended to be healthier and younger than their counterparts who ate fried
fish. They were more physically active and fit, more educated and less likely
to smoke, have diabetes, high blood pressure and heart disease. Furthermore, their
diets contained more fruits and vegetables, less unhealthy, saturated and trans
fatty acids and more beneficial fatty acids, which are found in fish and in non-marine
foods such as nuts, seeds and certain vegetable oils. Consumption of fried fish
was associated with higher body mass index, higher calorie intake and lower fiber
consumption. Consumption of other fried foods besides fish was adjusted in the
analysis. "Baking or broiling fish and eating it frequently seem to
be part of a dietary pattern that is very beneficial for a number of things,"
said Lloyd-Jones, associate professor, preventive cardiologist and chair of the
Department of Preventive Medicine at Northwestern University Feinberg School of
Medicine in Chicago. "In this case, we demonstrated that it's associated
with heart failure prevention. This suggests that fish is a very good source of
lean protein that we ought to be increasing as a proportion of our diet and decreasing
foods that contain less healthy saturated and trans fats." The results
of this study are consistent with previous findings in studies of older American
and Swedish populations, he said, "but the new study adds the interesting
results on darker fish. They also suggest that baked/broiled fish is associated
with reduced risk of heart failure through mechanisms other than reducing risk
for a heart attack, a precursor to heart failure in some people." Co-authors
are: Rashad J. Belin, Ph.D., M.S.C.I.; Philip Greenland, M.D.; Lisa Martin, M.D.;
Albert Oberman, M.D.; Lesley Tinker, Ph.D.; Jennifer Robinson, M.D.; Joseph Larson,
M.S.; and Linda Van Horn, Ph.D., R.D. Author disclosures are on the manuscript.
The National Heart, Lung, and Blood Institute funded the study. |