Antihypertensive Effect and Safety of Dietary .ALPHA.-Linolenic Acid in Subjects with High-Normal Blood Pressure and Mild Hypertension

Abstract

We investigated the antihypertensive effect and safety of a-linolenic acid (ALA) in human subjects. In Experiment 1, subjects with high-normal blood pressure and mild hypertension ingested bread containing 14 g of common blended oil (control oil) or ALA-enriched oil for 12 weeks. The test oil contained 2.6g/14 g of ALA. The subjects ingested strictly controlled meals during the study period. Systolic blood pressure was significantly lower in the ALA group than in the control group after ingestion of the test diet for 4, 8 and 12 weeks. Diastolic blood pressure was significantly lower in the ALA group than in the control group after ingestion of the test diet for 12 weeks. In Experiment 2, we evaluated the safety of high intake of ALA (7.8g/d), particularly its effects on oxidation in the body and blood coagulation. Normotensive, high-normotensive and mildly hypertensive subjects ate bread that contained 42 g of the control oil or the test oil for 4 weeks. No significant difference was noted in the lipid peroxide level, high-sensitive C-reactive protein level, plasma prothrombin time or activated partial thromboplastin time between the two groups. No abnormal changes were noted after test diet ingestion on blood test or urinalysis, and no adverse event considered to have been induced by the test oil was observed in Experiment 1 and 2. These results suggest that ALA have an antihypertensive effect with no adverse effect in subjects with high-normal blood pressure and mild hypertension.

Dietary Alpha-Linolenic Acid Inhibits Angiotensin-Converting Enzyme Activity and mRNA Expression Levels in the Aorta of Spontaneously Hypertensive Rats

“…Some epidemiological studies have also demonstrated that dietary intake of ALA is inversely associated with blood pressure [12][13][14][15] . Recently, we showed that a diet supplemented with ALA lowered systolic blood pressure (SBP) and diastolic blood pressure after 12 weeks in Japanese subjects with high-normal blood pressure and mild hypertension 16) . However, the antihypertensive mechanism of ALA is not fully understood.…”

Improvement in Storage Stability of Fish Fillets Using Dietary Soybean Phosphatidylcholine and Phosphatidylethanolamine

“…N-3 polyunsaturated fatty acids (PUFAs), such as α-linolenic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), have been attracting attention regarding their preventive effects against diseases such as atherosclerosis, coronary arterial heart diseases, and hypertension (Conner, 2000;Takeuchi et al, 2007). N-3 PUFAs are easily oxidized because they contain many double bonds.…”

Effect of Dietary Alpha-Linolenic Acid on Vascular Reactivity in Aorta of Spontaneously Hypertensive Rats

“…Some epidermal studies have also demonstrated that dietary intake of ALA is inversely associated with blood pressure [16][17][18][19] . Recently, we showed that a diet supplemented with ALA lowered systolic blood pressure (SBP) and diastolic blood pressure (DBP) after 12 weeks in Japanese subjects with high-normal blood pressure and mild hypertension 20) . However, the antihypertensive mechanism of ALA is not fully understood.…”