DHA but not EPA lowers Ambulatory Blood Pressure

Objective

Earlier animal studies have reported that the 2 major omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), might have differential effects on blood pressure BP and heart rate (HR).

This particular study was conducted to assess the differences in the effects of EPA or DHA on ambulatory (BP) and HR in humans.

Study population

57 men and women, 21-80 years of age, with fasting HDL levels of ≤ 44 mg/dl (in men) and ≤ 54 mg/dl (in women).

Study design

A double-blind, placebo-controlled parallel design trial

Length of study

6 weeks

Intervention

4 g/day of DHA, EPA or placebo respectively

DHA supplementation in men and women with below average HDL level, significantly reduced 24-hour BP and 24-hour HR

Results

DHA therapy significantly reduced the 24-hour and daytime (awake) ambulatory BP (p<0.05).

The 24 h and daytime BP values were found to be reduced by 5.8/3.3.

DHA supplementation reduced 24-h heart rate (HR), daytime HR and nighttime HR by 3. 5±0.8 bpm, 3.7±1.2 bpm, and 2. 8±1.2, respectively.

The EPA supplementation did not show any significance in controlling ambulatory BP or HR.

Conclusion

DHA is the principal omega-3 fatty acid and is associated with significant reductions in ambulatory blood pressure and heart rate. Thus, these results indicate the important implications of DHA for human nutrition and the food industry.

Source

Maki KC, et al. Lipid responses to a dietary docosahexaenoic acid supplement in men and women with below average levels of high density lipoprotein cholesterol. J Am Coll Nutr. 2005; 24(3):189-199.