Abstract 1149: Plant Biotechnology and Heart Health: The Effects of Stearidonic Acid-Enriched Soybean Oil on the Omega-3 Index and Other Markers
Background: As fish stocks decline, an alternative plant-based source of omega-3 fatty acids (FAs) is needed, and one that is more effectively converted to EPA and DHA than alpha-linolenic acid (ALA) is preferred. Stearidonic acid (SDA) is the product of the rate-limiting enzyme (delta-6 desaturase) in the conversion of ALA to EPA, and through biotechnology, can be produced at levels of 20%–30% in soybean oil (SDA SBO).
Objective: To compare the effects of SDA SBO to EPA and to regular SBO on red blood cell (RBC) EPA+DHA levels (the omega-3 index) and other markers of cardiovascular health.
Methods: Healthy volunteers (n=252) were randomized to treatment with SDA SBO (15 g/day providing 4.1 g SDA) plus 1 g/day SBO oil in gelcaps (SDA group) or to 15 g/day regular SBO with either EPA ethyl esters (1 g/d; EPA group) or 1 g/day SBO oil in gelcaps (control group). The omega-3 index, serum lipids, blood pressure, heart rate, adiponectin, C-reactive protein and safety laboratory measures were obtained at baseline and after 12 weeks. ANCOVA was used including age, sex and body mass index as covariates.
Results: A per-protocol analysis was conducted on 157 subjects. The overall mean (±SD) omega-3 index at baseline was 4.3±1.1%. The omega-3 index was unchanged at 12 weeks in the control group but increased by 17.7% in the SDA group and by 19.7% in the EPA group (ANCOVA, both p<0.001) vs. control. RBC DHA levels did not change in any group. Relative to EPA, SDA increased RBC EPA with about 18% efficiency. None of the other endpoints were affected by SDA or EPA treatment. Fasting triglycerides were reduced 26–30% by SDA or EPA treatment vs. control (p=0.029) for a subset population with baseline TG levels >150 mg/dL, when assessed by a post hoc repeated measures analysis. There were no adverse treatment-related effects.
Conclusions: SDA SBO significantly raised the omega-3 index. Based on epidemiological and clinical trial data, a change in the omega-3 index such as that observed here would be expected to reduce risk for major cardiac events, including sudden cardiac death. SDA SBO may be a viable plant-based approach to providing meaningful intakes of cardioprotective omega-3 FAs. Further research on triglyceride-lowering effects of SDA SBO is warranted.
Sponsorship: Monsanto Co, Solae LLC