Consumption of chia seeds, rich in alpha-linolenic acid, may increase blood levels of the long-chain omega-3 eicosapentaenoic acid by 30% for postmenopausal women, says a new study from the Appalachian State University and the University of North Carolina.
Twenty-five grams per day of milled chia seed for seven weeks were associated with a 138% increase in levels of alpha-linolenic acid (ALA) and a 30% increase in eicosapentaenoic acid (EPA) levels, according to data presented in Plant Foods for Human Nutrition.
While there was significant variation between the women in the study, the study does support previous findings about the conversion of ALA to EPA, said the researchers.
“A cardioprotective effect of high, long-term ALA intake has been suggested by a number of epidemiological studies, and an additive effect of ALA with omega-3 long-chain PUFA from fish and fish oil has been observed.”
ALA omega-3 is an essential fatty acid that the body cannot make and therefore must be consumed in the diet. Good sources of ALA include flaxseed, soybeans, walnuts, chia and olive oil. The U.S. Institute of Medicine recommends an ALA intake of 1.6 grams per day for men and 1.1 grams per day for women.
The health benefits associated with ALA consumption include cardiovascular effects, neuro-protection, a counter to the inflammation response and benefits against autoimmune disease.
However, the longer-chain EPA and DHA (docosahexaenoic acid) have received more study from scientists and more attention from consumers.
Much attention has been paid to the conversion of ALA to the longer chain EPA, with many stating that this conversion is very small. According to an article in Nutrition Reviews (Vol. 66, pp. 326-332), between eight percent and 20% of ALA is converted to EPA in humans and between 0.5% and nine percent of ALA is converted to DHA.
In addition, gender plays an important role, with women of reproductive age reportedly converting ALA to EPA at a 2.5-fold greater rate than healthy men.
This conversion obviously contributes to the body’s pool of EPA and DHA, which plays a key role in, among other things, maintaining cardiovascular health.
The North Carolina-based scientists recruited 10 postmenopausal women and assigned them to consume 25 grams per day of milled chia seed for seven weeks.
“Plasma EPA increased 30% above baseline levels in the present study, but individuals varied widely both pre-study and in response to milled chia seed supplementation.
“The 30% increase in plasma EPA in our subjects (postmenopausal women) following seven weeks of chia seed ALA supplementation (4.1 g/day) is comparable to other similar studies.”
Plant Foods for Human Nutrition 67(2):105-110, 2012