RBC Level of Omega-3 Fatty Acids Inversely Correlated with Brain Volume Atrophy
By Carrie Decker, ND
Founder and Medical Director, Blessed Thistle, Madison, WI
Dr. Decker reports no financial relationships relevant to this field of study.
Synopsis:Higher combined eicosapentaenoic acid and decosahexaenoic acid level in red blood cells is correlated with decreased total brain and hippocampus volume atrophy in postmenopausal women 8 years later.
Source:Pottala JV, et al. Higher RBC EPA + DHA corresponds with larger total brain and hippocampal volumes: WHIMS-MRI Study. Neurology 2014 Jan 22; [Epub ahead of print].
Brain volume atrophy, particularly in the hippocampus region, is seen with the development of the dementia of Alzheimer's disease (AD). Decosahexaenoic acid (DHA) is the fatty acid that makes up 30-40% of the gray matter of the cerebral cortex. Decreased serum, brain, and neuronal DHA and/or eicosapentaenoic acid (EPA) have been found in patients with AD. These factors promote interest in further evaluation of brain volume associated with EPA and/or DHA status.
A population of 1111 postmenopausal women from the Women's Health Initiative Memory Study were the subjects of this study. The RBC levels of EPA, DHA, and combined EPA and DHA were measured and compared to the brain volume in 13 regions measured by MRI an average of 8 years later. Findings were adjusted for multiple factors including hormone therapy, intracranial volume, time, and cardiovascular risk factors. Individuals who experienced a stroke or transient ischemic attack in the 8-year period were excluded. Significant findings were that one standard deviation increase in RBC EPA + DHA level was associated with a 2.1 cm3 increase in total brain volume (P = 0.048; 95% confidence interval [CI], 0.0-4.3 cm3) and a 50 mm3 increase in hippocampal volume (P = 0.036; 95% CI, 3-97 mm3). One standard deviation increase in DHA was associated with a 2.0 cm3 increase in total brain volume, a marginally significant finding with P = 0.063. Information about omega-3 supplementation during the 8-year period and measurements of RBC fatty acid levels at the time of MRI assessment were not included in this study.
The results from this study add to the growing body of evidence about omega-3 fatty acids and brain health. For example, DHA and total fatty acid levels have been shown to be significantly lower in individuals with Alzheimer's disease and cognitive impairment.1 However, this study is only a preliminary finding, a correlation that needs to be corroborated by a controlled clinical trial before sweeping changes are made in the clinical use of omega-3s in this context. Furthermore, as described in a related review about omega-3 levels,2 there is some debate about the best way to determine an individual's omega-3 status. Nonetheless, these are intriguing findings, which, given the overall safety profile of dietary and supplemental omega-3s, further nudge clinicians to expanding the recommendations about omega-3 intake.
- Conquer JA, et al. Fatty acid analysis of blood plasma of patients with Alzheimer's disease, other types of dementia, and cognitive impairment. Lipids 2000;35:1305-1312.
- Fortney L. Omega 3s and the prostate: Good or bad? Integrative Med Alert 2013;8:85-88.