Oily fish and fish oil supplements contain EPA and DHA, two types of omega-3 fatty acids that are important for our brain, nervous system, and mental health throughout life. According to a new Irish study, young adults with higher blood levels of omega-3are less likely to develop depression and anxiety. The researchers see a huge therapeutic potential in advising people to increase their omega-3 intake from oily fish or supplements. The problem is that modern diets contain far too little omega-3 and too much omega-6, which contributes to the increased rate of mental illness.