The study published in the medical journal Experimental psychology suggests that the harmful effects from fast food or from other fatty meals can be substantially reduced by eating fatty fish. For example, you should eat mackerel, sardines or salmon twice a week to re balance your diet and boost your immune system. This would be due to the high concentration of fatty acids and omega 3 that this type of fish contains. However, researchers point out that not everyone can benefit from this, particularly those who are significantly overweight. Needless to say, your fish shouldn't be deep fried if you want it to be healthy. So, the best thing is to stick to a varied and balanced diet!