Studies have found that long chain omega 3 fatty acids, from oily fish such as salmon, trout, mackerel and sardines, may be useful in the prevention and treatment of depression and low mood.  Now research has found (1) that eating trans-fats  may increase the risk of suffering depression, and that olive oil may protect against depression.     Trans fatty acids are created through manufacture when liquid vegetable oils are hardened, to a solid or semi-solid state, via a process known as hydrogenation.  (Hydrogenation is when naturally occurring cis-unsaturated double bonds are converted into trans unsaturated double bonds).  The process of hydrogenation also destroys the essential short chain omega 3 fatty acid alpha-linolenic acid from oils (for more information about the health benefits of omega 3 fats please read through my previous posts on the subject).  Trans fatty acids have been linked to various adverse health effects, for more information please read this post     The study ran from 1999-2010 and involved 12,059 Spanish university graduates with an average age of  37.5 years.  All of the participants were initially free of depression.  At the beginning of the study a detailed and extensive food frequency questionnaire was used to estimate the intake of fatty acids.  During the six year follow-up period any cases of depression, as diagnosed by a physician, were reported.  In this time over 650 new cases of depression were identified.  Results found that trans fatty acids were associated with an increased risk of depression – the more trans….