Omega-3s? They lower high blood pressure!

The Omega 3 contained in fish or supplements are able to lower blood pressure. The magnitude of this effect is equal to or even greater than when reducing alcohol consumption, salt consumption and increasing physical activity. Daily consumption of EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) could help limit the use of blood pressure control medications.

This was reported in research conducted at the Center for Epidemiology, Biostatistics and Computational Biology, in Colorado, USA. The meta-analysis study, that is, conducted on numerous trials, was published in the American Journal of Hypertension.

Hypertension: often due to incorrect lifestyles

Elevated blood pressure or hypertension affects about 33 percent of men and 31 percent of women in Italy, and can cause coronary artery disease and heart failure. The value of blood pressure is given by systolic and diastolic pressure. The former is measured at the time the heart contracts and pumps blood into the arteries, the latter as the heart relaxes and fills with blood. A blood pressure that exceeds 140 mmHg for systolic and 90 mmHg for diastolic is considered high. Most cases of hypertension are due to unhealthy lifestyles including poor diet, alcohol abuse, sedentary lifestyle, and smoking and stress.

Major effects on hypertensive patients

The study looked at 70 trials conducted on adults who received EPA + DHA in supplement form or by consuming fish for more than 3 weeks, and on adults who received a placebo. Some of the subjects involved suffered from high blood pressure but were not taking medication, while others had normal blood pressure. Compared with the placebo group, consumption of EPA and DHA caused an average decrease in systolic blood pressure of 1.52 millimeters Hg and diastolic pressure of 0.99 millimeters Hg in all treated subjects. The most significant treatment effects, however, were observed in hypertensive adults in whom the average decrease in systolic blood pressure was 4.51 mmHg and diastolic 3.05 mmHg. Normotensive people also benefited from the treatments, showing a decrease in systolic blood pressure of 1.25 mmHg and diastolic of 0.62 mmHg . Reduction in systolic blood pressure by 1.75 mmHg and diastolic by 1.11 mmHg was also shown among subjects taking fish oil supplements, regardless of initial blood pressure status. The results observed in hypertensive patients proved to be the same, if not greater in some cases, than the effects of an appropriate lifestyle. Indeed, previous studies have shown that reducing salt consumption decreased systolic blood pressure by 3.6 mmHg, increasing physical activity by 4.6 mmHg, and reducing alcohol consumption by 3.9 mmHg.

EPA and DHA reduce blood pressure

Collectively, data indicate that the intake of at least 2 g of EPA + DHA per day can reduce blood pressure with greater benefits among hypertensive individuals who do not use antihypertensive drugs. A lower dose (between 1 and 2 gr per day) may reduce systolic blood pressure but not diastolic. According to the researchers, the effect on blood pressure by Omega-3s would be due to their ability to regulate the functions of the endothelium, which is the thin layer of cells that lines the inside of blood vessels. The endothelium possesses a central role in the regulation of blood pressure. Indeed, recent studies have shown improved endothelial function in response to EPA and DHA in subjects with hypertension and at risk for cardiovascular disease. These findings have important clinical relevance: a 2 mm Hg reduction in blood pressure reduces the risk of stroke mortality by 6%, heart disease mortality by 4%, and overall mortality by 7%.

Source:

Paige E. Miller,Mary Van Elswyk^, and Dominik D. Alexander . "Long-Chain Omega-3 Fatty Acids Eicosapentaenoic Acid and Docosahexaenoic Acid and Blood Pressure: A Meta-Analysis of Randomized Controlled Trials. "Am J Hypertens (2014) doi: 10.1093/ajh/hpu024First published online: March 6, 2014