Fish has long been hailed as "brain food," and now new data suggest fish contains ingredients that may contribute to brain health.
Researchers studied 1,000 postmenopausal women, looking at their levels of two fatty acids found in fish, called eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
They found that women with significantly higher levels of the two fatty acids in their red blood cells also tended to have larger brains, and larger hippocampuses, the part of the brain associated with forming memories.
Studies have shown that in older adults, the brain generally shrinks with aging.
In the study, researchers looked at MRIs of brain volume and red blood cell levels of DHA and EPA in 1,111 postmenopausal women who were part of the Women's Health Initiative Memory Study. They took measurements eight years later to determine the differences in the size of the women's brains, and found the link between fatty acid levels and brain volume.
Researchers found that a 2.7 percent larger hippocampus brain volume was associated with increasing from a low to a high EPA and DHA level. The levels seen in the women in the study could be obtained by eating non-fried 'oily' fish (such as salmon, tuna, herring or sardines) at least twice a week, and taking fish oil supplements.
While the brain volume data is encouraging, it is still only a waypoint in determining whether keeping levels of these fatty acids higher can actually stave off dementia.
Researchers hypothesize that the presence of EPA and DHA may help prevent shrinking in the brain, either because DHA is used in anti-inflammatory compounds that prevent cell death, or because it is used in the construction of the membranes of brain cells, but the exact reason for the connection requires further study.