A search of the literature in Pub Med (3/29/2011), using the search terms depression and inflammation, reveals over 1700 documents published in the medical literature since 1922. A tentative link between depression as a mental health issue and inflammation was first made in 1981 when Horrobin and Lieb suggested that inflammation and immune disorders could be thought of as “manic depression of the immune system.” It took another twenty years before it was noticed that elevated levels of inflammatory markers associated with heart disease were also seen in depressed patients who had no history of heart disease.  But by the middle of the first decade of the new millennium, a burst of studies appear that note the link between inflammatory biomarkers and clinical depression [3-8] and dementia [9-11].
The role of the immune system was starting to be explored as a co-factor as well. By 2010 links were reported between depression, inflammation and the immune system and a variety of disease states including depression[12-18], dementia [9-11], multiple sclerosis, heart disease [20-27], arthritis , and even dental diseases . Also by 2010, the evidence base seemed clear that there was some link between inflammation, the immune system and depression, but it was not at all clear what the causal link was. The evidence base exploded in the first quarter of 2011 with 24 articles compared to 34 articles in the entire year for 2010. It could be concluded that the research community has found a new thread with a growing popularity. But has any of this science been practically applied in the clinical trenches?
As we might expect, the pharmaceutical industry may be intrigued by the possibility of developing new psychiatric drugs based upon the underlying mechanisms of either inflammation or immunomodulation. There is even speculation that the actual benefit of current antidepressant medications may be due to their anti-inflammatory effects rather than their effects on catecholamines. [5, 31] This opens up an area of speculation. Since there are many foods with anti-inflammatory effects [32-43], could we eat our way out of depression?
Obviously whole natural food has limited amounts of anti-inflammatory flavonoids per kilo of food mass. This limits the amount a person could be expected to consume. If the effective flavonoids could be isolated and a nutraceutical could be prepared, we might have a way to test the hypothesis that depression can be reduced by ingestion of ant-inflammatory foods. One nutraceutical preparation combines curcumin with scutellaria (a Chinese medicinal herb) and acacia derived from the bark of the boxwood tree. This combination was shown to reduce both COX and LOX enzymes to safe natural levels producing a corresponding reduction in systemic inflammation.  This preparation was also found to be both safe and effective in double blind, placebo controlled trials, comparing the preparation to standard anti-inflammatory medications for arthritis. [45-47]
To date I know of no research examining the effect of such natural anti-inflammatory foods on neurodegenerative conditions such as depression, anxiety and dementia. In fact, despite the ample evidence of the negative effects of inflammation and oxidative stress on neurodegeneration, I have been unable to find any research on the therapeutic effects of anti-inflammatory or antioxidant diet or supplementation. I have noticed anecdotally that a product containing anti-inflammatory flavonoids, anti-oxidants and a combination of other herbs and plant fractions has resulted in improved mood, mental energy, clarity and focus as well as stress resilience for many of my depressed patients. This product, manufactured by the Univera company, has caused me to question whether it is time to try to obtain a formal research grant for a double blind human trial with clinically depressed individuals.
Please add your comments if you have personal or professional experience with this or other plant based natural anti-inflammatory products affecting the course of depression.
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