Practical alternative to fish oil for getting essential Omega-3
By Science News Staff / Source
“Given
the evidence of the health benefits of plant-based diets and long-chain n-3
fatty acids, there is keen interest in better understanding the role of
alpha-linolenic acid (ALA), a plant-derived n-3 fatty acid, on cardiometabolic
diseases and cognition,” said lead author Dr. Aleix Sala-Vila, a researcher at
the Institut Hospital del Mar d’Investigacions Mèdiques-Barcelona, and
colleagues.
“There
is increasing evidence for ALA largely based on its major food sources (i.e.,
walnuts and flaxseed); however, this lags behind our understanding of
long-chain n-3 fatty acids.”
For
their review, the authors analyzed data from previous studies to evaluate the
effects of ALA on heart disease and heart disease risk factors like blood
pressure and inflammation.
They
analyzed included both randomized controlled trials and observational studies.
While some of the observational studies relied on the participants reporting how often they ate certain foods to determine how much ALA they were consuming, others used biomarkers — a way of measuring levels of ALA in the blood — as a more accurate measure.
After
analyzing the studies, the researchers found that consuming ALA was associated
with a 10% lower risk of cardiovascular disease and a 20% reduced risk of fatal
coronary heart disease.
They
also found ALA had beneficial effects on reducing atherogenic lipids and
lipoproteins as well as blood pressure and inflammation.
“People
may not want to eat seafood for a variety of reasons, but it’s still important
for them to consume omega-3s to reduce the risk of heart disease and to promote
overall health,” said Professor Penny Kris-Etherton, a researcher in the
Department of Nutritional Sciences at Pennsylvania State University.
“Plant-based
ALA in the form of walnuts or flaxseeds can also provide these benefits,
especially when incorporated into a healthy diet rich in fruits, vegetables,
and whole grains.”
“We
also found evidence that for people who do eat seafood, they could get extra
benefits from eating plant-based omega-3s,” added Dr. Jennifer Fleming, also
from the Department of Nutritional Sciences at Pennsylvania State University.
“We
were able to find evidence supporting current dietary guidelines that ALA
should provide about 0.6-1% of total energy in a day, which is about 1.1 grams
a day for women and 1.6 grams a day for men, and can be incorporated into the
diet with foods such as walnuts, flaxseeds, and cooking oils such as canola and
soybean oils,” said Dr. Emilio Ros, a researcher at the Institut
d’Investigacions Biomèdiques August Pi i Sunyer and the CIBER Fisiopatología de
la Obesidad y Nutrición at the Instituto de Salud Carlos III.
These
recommendations are equal to about 1/2 ounce of walnuts or just under one
teaspoon of flaxseed oil.
“Future
studies are needed to help better understand the effects of ALA on other major
chronic diseases,” the scientists said.
“In
addition, there is a need to evaluate whether the recent scientific literature
supports new, higher dietary recommendations for ALA.”
_____
Aleix
Sala-Vila et al. Impact of Alpha-linolenic Acid, the Vegetable
Omega-3 Fatty Acid, on Cardiovascular Disease and Cognition Get access
Arrow. Advances in Nutrition, published online February 16, 2022;
doi: 10.1093/advances/nmac016