|
U.S. Agency Confirms Fish Oil Helps Fight Heart
Disease
Other benefits include lower blood pressure, less
risk of artery reblockage, increased exercise ability and reduced risk
of irregular heart beat
April 23, 2004 - Fish oil can help reduce deaths
from heart disease, according to new evidence reports announced
yesterday by the Agency for Healthcare Research and Quality. The
systematic reviews of the available literature found evidence that long
chain omega-3 fatty acids, the beneficial component ingested by eating
fish or taking a fish oil supplement, reduce heart attack and other
problems related to heart and blood vessel disease in persons who
already have these conditions, as well as their overall risk of death.
Although omega-3 fatty acids do not alter total
cholesterol, HDL cholesterol, or LDL cholesterol, evidence suggests that
they can reduce levels of triglycerides—a fat in the blood that may
contribute to heart disease.
The review also found other evidence indicating
that fish oil can help lower high blood pressure slightly, may reduce
risk of coronary artery re-blockage after angioplasty, may increase
exercise capability among patients with clogged arteries, and may
possibly reduce the risk of irregular heart beats—particularly in
individuals with a recent heart attack.
"These findings will help health care professionals
and the public understand which benefits of omega-3 fatty acids have
been scientifically proven and pinpoint areas where additional evidence
is needed," said Carolyn M. Clancy, M.D., AHRQ's Director. "Translating
scientific evidence into information that can be used to improve health
and heath care is key to AHRQ's mission."
The evidence reports of the health effects of
omega-3 fatty acids are part of a series conducted by AHRQ-supported
Evidence-based Practice
Centers at the request of the National Institutes of Health's Office
of Dietary Supplements, which plans to use the findings to develop
research agendas on the issues. Five reports are currently being issued,
and an additional six reports will be issued next year.
Paul M. Coates, Ph.D., Director of NIH's Office of
Dietary Supplements, said, "The reports describe some positive findings
as well as a number of areas where data are insufficient to draw
conclusions about the efficacy and safety of omega-3 fatty acids. The
Office of Dietary Supplements, in collaboration with other NIH
institutes, will use these reports to develop appropriate research
agendas for omega-3 fatty acids that will fill these gaps in knowledge."
Findings from the three other AHRQ evidence reviews
indicate that:
-
Omega-3 fatty acids do not affect fasting blood
sugar or glycosylated hemoglobin in people with type II diabetes,
nor do they appear to affect plasma insulin levels or insulin
resistance.
-
Alpha-linolenic acid (ALA), a type of omega-3
fatty acid from plants such as flaxseed, soybeans, and walnuts, may
help reduce deaths from heart disease, but to a much lesser extent
than fish oil.
-
Based on the evidence to date, it is not
possible to conclude whether omega-3 fatty acids help improve
respiratory outcomes in children and adults who have asthma.
-
Omega-3 fatty acids appear to have mixed
effects on people with inflammatory bowel disease, kidney disease
and osteoporosis, and no discernible effect on rheumatoid arthritis.
The evidence reports and Evidence-based Practice
Centers that produced them are: Effects of Omega-3 Fatty Acids on
Cardiovascular Disease, Effects of Omega-3 Fatty Acids on
Cardiovascular Risk Factors and Intermediate Markers for Cardiovascular
Disease, and Effects of Omega-3 Fatty Acids on Arrhythmogenic
Mechanisms in Animal and Isolated Organ/Culture Studies (Tufts-New
England Medical Center EPC, Boston); Health Effects of Omega-3 Fatty
Acids on Asthma (University of Ottawa EPC, Ottawa, Ontario);
Health Effects of Omega-3 Fatty Acids on Lipids and Glycemic Control in
Type II Diabetes and the Metabolic Syndrome, and on Inflammatory Bowel
Disease, Rheumatoid Arthritis, Renal Disease, Systemic Lupus
Erythematosus, and Osteoporosis (Southern California-RAND EPC, Santa
Monica).
Summaries of evidence reviews are available on
AHRQ's Web site at
www.ahrq.gov/clinic/epcindex.htm#dietsup, and on the National
Guideline Clearinghouse™ Web site at
www.guideline.gov (select "EPC reports"). Free printed copies are
available from the AHRQ Publications Clearinghouse by calling
1-800-358-9295 or sending an E-mail to
ahrqpubs@ahrq.gov.
|
