Individuals carrying low-to-moderate dementia risk associated with APOE genotypes demonstrated a significantly lower risk of developing dementia with higher blood levels of PUFA [Low-to-moderate vs. high: 0.74 (0.64,0.84) vs. 0.90 (0.78,1.03)], N6FA [0.69 (0.59,0.81) vs. 0.88 (0.75,1.04)], DHA [0.25 (0.07,0.92) vs. 0.98 (0.29,3.28)], and LA [0.68 (0.58,0.80) vs. 0.89 (0.75,1.05)], compared with those carrying high-risk APOE genotypes (P interaction < 0.05). The gene discussed is APOE; the disease is dementia.