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

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.

DHA shows Beneficial Effects on Cardiovascular Risk Factors

Objective

The consumption of long-chain omega-3 polyunsaturated fatty acids (PUFA), including docosahexaenoic acid (DHA) is associated with reduced risk of cardiovascular disease

A double-blind randomized placebo-controlled parallel-design trial was conducted to assess the beneficial effects of algal oil supplement on cardiovascular risk factors.

Study population

39 men and 40 women

Length of study

4 weeks

Intervention

Subjects were randomized to receive 4 g/day of the algal oil (containing 1.5 g DHA and 0.6 g docosapentaenoic acid (DPA)) or placebo respectively.

Results

• The plasma concentrations of arachidonic acid, adrenic acid, DPA and DHA were significantly increased by 21, 11, 11 and 88 mg/L, respectively in the DHA/DPA oil group compared to placebo (see Fig. 1). The proportions of DPA and DHA in erythrocyte phospholipids were increased by 78% and 27% in DHA/DPA supplemented group.
• The serum total, LDL-cholesterol and HDL-cholesterol levels were found to increase by 0.33mmol/L (7.3%), 0.26mmol/L (10.4%) and 0.14mmol/L (9.0%) in the DHA/DPA supplemented group compared to placebo (p for all ≤ 0.001).
• Furthermore the Factor VII (FVII) coagulant activity was also found to increase by 12 % in the DHA/DPA treatment group (p=0.006).

Conclusion

DHA/DPA oil supplementation is generally well tolerated and results in significant reductions in the cardiovascular risk factors

Source

Sanders TA, et al. Influence of an algal triacylglycerol containing docosahexaenoic acid (22:6n-3) and docosapentaenoic acid (22:5n-6) on cardiovascular risk factors in healthy men and women. Br J Nutr. 2006; 95(3):525-531.

DHA Significantly Reduces the Lipid and Triglyceride levels

Objective

Randomized, double-blind, controlled clinical trial was conducted to assess the effect of docosahexaenoic acid (DHA) supplementation on fasting lipid responses in men and women with below-average levels of high-density lipoprotein (HDL) cholesterol.

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)

Length of study

6 weeks

Intervention

Subjects were randomized to receive 1.52 g/day DHA from DHA rich algal triglycerides or olive oil as a control, respectively.

DHA supplementation significantly reduces triglyceride level and triglyceride/HDL cholesterol ratio

Results

• DHA supplement showed a significant change in the triglyceride levels, total and LDL-C levels compared to placebo (see Fig. 1). Furthermore the percentage changes were significantly higher in DHA group and [-21 % (DHA) vs. -7% (controls), p=0.009] in triglycerides, total [6% vs. 2%; p=0.018] and low-density lipoprotein [12% vs. 3%; p=0.001] cholesterol concentrations.
• The triglyceride to HDL cholesterol ratio [-1.33 vs. -0.50, p=0.010], also significantly reduced in DHA supplemented group compared to control.
• A significant reduction in the percentage of LDL cholesterol carried by small, dense particles was found in the DHA supplemented group (changes =-10% vs. -3%, p=0.025) in comparison to the placebo.

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.

DHA increases duration of gestation

Objective

The effectiveness and role of docosahexaenoic acid (DHA) has been proved by numerous clinical studies. The polyunsaturated fatty acids (PUFAs) during pregnancy or early postpartum period have been found to have beneficial effects on duration of gestation . A randomized, double-blind, controlled, clinical trial was conducted to determine the effects of increasing DHA intake during the third trimester of pregnancy on overall pregnancy and birth outcomes. The figure depicts the study design and the observations made.

Results

• Based on the study outcomes, the following observations were made:
• infant but not maternal red blood cell (RBC) phospholipid DHA increased significantly in the high DHA group
• High-DHA group had a significant increase in duration of gestation of 6.0 ± 2.3 days compared with the ordinary DHA group (276.5 days vs. 270.5 days, p=0.009).
• Infants in the DHA supplemented group were significantly longer at delivery (p=0.048) and had a trend toward larger head circumference (p=0.081).

Conclusion

• Duration of gestation increased significantly when docosahexaenoic acid intake was increased during the last trimester of pregnancy.
• The increase in gestation was similar to that of previously reported interventions with much larger amounts of n-3 long chain polyunsaturated fatty acids

Source

Smuts CM, Huang M, Mundy D et al. A randomized trial of docosahexaenoic acid supplementation during the third trimester of pregnancy. Obstet Gynecol. 2003;101(3):469-479..