High consumption of fish or fish oil has been linked to the maintenance of healthy cognition in epidemiological studies. Previous clinical trials have shown conflicting results regarding omega-3 supplementation in cognitive impairment. Two new randomized trials join in. In the first study DHA supplementation with a high dose of 2 g for 1,5 years did not result in any significant outcome versus placebo among Alzheimer’s patients. (Quinn J et al. JAMA 2010; 304: 1903-1911). In another recent trial, a lower dose of DHA (0.9 g/day) improved some cognitive parameters but not all when compared to placebo (Yurko-Mauro et al. Alzheimers Dement 2010;6:456-464). According to the researchers omega-3 fatty acids may be protective in maintaining healthy cognition or improving mild cognitive impairment but it might be too late to use them in established Alzheimer’s disease.