For the next several posts, I plan to discuss the B vitamin folate (vitamin B 9) and an enzyme, methylenetetrahydrofolate reductase (MTHFR from now on:)) which is critical for folate to become functional in the body. This is not a random or obscure line of thought but rather one of the most fascinating areas of medical research relating to wellness and prevention. MTHFR dysfunction has long been known to play a role in early miscarriage. Also, folate is routinely supplemented in pregnancy to prevent neural tube defects. Beyond that we see a connection with heart disease and stroke, blood clots, dementia and many cancers. What I want to focus on, however is MTHFR/folate’s relationship to depression. Together with some of my colleagues, I recently heard a fascinating lecture by Vlademir Maletic, a Clinical Professor of Neuropsychiatry at the University of South Carolina School of Medicine.  He presented the physiologic basis for a connection between obesity, depression and inflammation and then tied in the critical role of the form of folate which is active in the brain (L-methylfolate). This correlated with some research we have been doing at Trinity/VitalSigns related to MTHFR. Again, MTHFR is the blood-drawenzyme which facilitates the conversion of folate to its active form L-methylfolate. We now are able to routinely do a blood test for abnormalities in the gene which codes for MTHFR. If a defective enzyme is being produced, adequate methylfolate is not being made and we can prescribe a supplement of methylfolate to treat related problems. Beyond that and more exciting to me, Dr. Maletic’s lecture outlined the elegant neuroscience behind the profound and specific impact of diet, exercise and stress on the viscous cycle of obesity, inflammation, depression and folate metabolism. I will first review inflammation’s effect on the brain and then its tie-in with depression and methylfolate. Stay tuned. This is very practical information which impacts all of our lives in many ways.