Fish oil deficiency can shrink your brain

October 19, 2013 
One of the most feared events for most elderly is "losing their minds". Of course Alzheimer’s disease tops the list in an extreme case of neurodegeneration but even mild cognitive impairment can be the beginnings of neurodegeneration, that is, losing the ability of brain neurons to send and receive signals properly. A study published in the journal Neurology studied 1,575 people with an average age of 67 and followed them for almost 3 years measuring their levels of EPA, DHA, and the omega-3 index. The omega-3 index measures the percentage of EPA and DHA in the red blood cells. Those that had the lowest levels of DHA, or docosahexaenoic acid, had greater cognitive impairment, decreased brain volume (smaller brains), and an increase in white matter hyperintensities. White matter hyperintensities are areas of bright white color in the brain on an MRI scan. These have been associated with decreased cognitive function as well as other neurological and psychiatric diseases. The authors of the study conclude, “Lower RBC (red blood cell) DHA levels are associated with smaller brain volumes and a “vascular” pattern of cognitive impairment even in persons free of clinical dementia.” 

References: 
Red blood cell omega-3 fatty acid levels and markers of accelerated brain aging. Neurology 2012; 78: 658–664. 

Medial temporal lobe atrophy and white matter hyperintensities are associated with mild cognitive deficits in non-disabled elderly people: the LADIS study. J Neurol Neurosurg Psychiatry. 2005 November; 76(11): 1497–1500.