Previous studies have shown that omega-3 fatty acids from fish oils reduce the risk of heart disease and sudden cardiac death. Consuming a small amount of fish, two or three times a week, has been found to offer heart protection. Fish and the algae they feed on contain high levels of omega 3 fattty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Now research reports that DHA supplementation can lower diastolic blood pressure in middle-aged adults.
The randomized, double-blind, crossover, placebo controlled study, published in The Journal of Nutrition, investigated the effect of DHA supplementation on vascular function. Researchers from the King's College London, UK administered either 0.7 grams of DHA or a placebo daily to 38 healthy, middle-aged men and women, for three months. DHA was not taken by either group for the following four months. The participants then switched regimens for another three months. Blood pressure measurements and blood and urine samples were obtained from the participants at each treatment phase.
Researchers found that DHA levels increased 58 percent in red blood cells and blood pressure was lowered when participants were administered DHA. The diastolic blood pressure (the bottom number in a blood pressure reading) dropped an average of 3.3 points and heart rate was lowered by 2.1 beats per minute after DHA treatment. However, arterial stiffness and endothelial function didn't change after DHA treatment.
"The results indicate that a moderate increase in the daily intake of DHA to approximately 0.7 g DHA lowers diastolic blood pressure but does not influence indices of endothelial function or arterial stiffness in the short term," the study authors write.
REFERENCES:
1. Theobald HE et al. Low-Dose Docosahexaenoic Acid Lowers Diastolic Blood Pressure in Middle-Aged Men and Women. J Nutr 2007 Apr;137(4):973-978.
Posted by Elaine Gavalas on March 30, 2007 02:57 PM
