Supplementation with omega-3 polyunsaturated fatty acids augments brachial artery dilation and blood flow during forearm contraction
Walser B, et al., Eur. J. Appl. Physiol., 97: in press (2006)
Department of Internal Medicine, University of California, Davis, CA, USA; Department of Physiology and Membrane Biology, University of California, Davis, CA, USA.
The authors investigated the potential for DHA/EPA omega-3 supplementation to enhance exercise-induced increases in blood flow which occurs during rhythmic exercise. The test subjects received a placebo (control) or daily supplementation with 2g of DHA plus 3g of EPA over a six week period. In contrast to placebo treatment which had no effect on any variable, DHA/EPA (combined) supplementation was found to produce a significant improvement in blood flow from an average of 293 up to 367 ml per minute along with enhanced contraction-induced increases in the brachial artery diameter. This 25% increase in blood velocities as measured in the exercising arm by ultrasound technology was considered by the authors to have potential important implications for individuals with cardiovascular disease and exercise intolerance such as in heart failure. The potential for dietary supplementation with DHA/EPA to enhance blood flow and oxygen delivery to exercising skeletal muscle led the authors to suggest that such treatment could delay the onset of fatigue and allow individuals to work at higher work loads for longer periods of time. The authors suggest that patients with exercise intolerance and conditions such as heart failure, hypertension, and diabetes might receive improved functional capacity and quality of life with these higher intakes of DHA plus EPA.
Dr. Holub's Comments:
The authors have made an important contribution to the potential for increased DHA/EPA omega-3 fatty acid intakes to enhance blood flow in normal exercising subjects and those with heart failure. It will be interesting to monitor future follow-up studies on this particular topic. It should be pointed out that the level of dietary supplementation employed with DHA/EPA (combined) amounted to 5 g / day. This level of intake is above the combined daily intake (DHA plus EPA) of 3 g / day which has been considered by the Food and Drug Administration to be the upper limit for general safety in most people.