A Comparison of Alternative Oil Supplements as a Source of Bioaccessible Key Fatty Acids

Alzheimer’s disease (AD) is a major health issue in ageing societies, possibly becoming more relevant in the future. This has elicited new treatments and the study of diets to prevent and delay AD. This study aimed to assess the effectiveness and challenges of alternative sources of biologically active fatty acids (FA) —namely, omega-3 polyunsaturated FA, n-3 PUFA— for preventing cognitive decline in AD. To this end, lipid class distribution, FA composition, and bioaccessibility were evaluated in linseed oil (LSO), fish oil (FO), Schizochytrium sp. oil (SCHO), and DHASCO oil (DHASCO). There were major differences between supplements. FO had the highest n-3:n-6 ratio, 11.1±0.3, and the other supplements lower ratios, 3.5-5.7. While FO had modest percentages of docosahexaenoic acid (DHA), ~10%, SCHO had a large share of DHA, ~40%, and DHASCO contained >70% DHA. Total lipid bioaccessibility was ≥77% and DHA bioaccessibility was 76±0%, 85±1%, and 88±2%, for DHASCO, SCHO, and FO, respectively. Considering bioaccessibility, a neuroprotective DHA intake of 2 g/day could be achieved with daily 25.2 g, 6.3 g, and 3.9 g of FO, SCHO, and DHASCO, respectively. Therefore, the SCHO and DHASCO supplements seem advisable. This study showed the importance of bioaccessibility in assessing dietary alternatives against AD.