APOE and Mental deterioration: A pursuant meta-analysis of the literature provided pooled effect estimates; studies adjusting for ApoE ε4 status reported that the risk of general cognitive decline was reduced by (8 studies, I2 = 65%) dietary ω-3 and by (9 studies, I2 = 42.4%) dietary DHA but not by general PUFA or EPA; this reduction vanished for studies not adjusting for ApoE ε4 status.