Many studies have already proven that vitamin B supplements can help slow mental decline in older individuals. But higher levels of Omega-3 fatty acids could boost the effect of vitamin B supplements. Researchers examined more than 250 individuals with mild cognitive impairment. Mild cognitive impairment is when brain function is below what is normally expected for an individual’s age, but not significant enough to affect everyday life.[1] Although it’s less serious than dementia, it often progresses to become dementia if untreated.
Earlier studies have found that vitamin B supplements can slow or prevent atrophy of the brain and memory decline in individuals with mild cognitive impairment. This was most effective in individuals who had above average blood levels of homocysteine. Homocysteine is a factor associated with B vitamin status that can be toxic to the brain. A connection between Omega-3 levels, homocysteine, and brain atrophy rates had already been established. The researchers wanted to determine whether Omega-3 and vitamin B supplements could interact to prevent cognitive decline.
At the beginning of the study, each individual was presented with a set of tests to measure their cognition. They also had a blood test to check the levels of 2 Omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
The participants were divided into 2 randomly-selected groups. One group received a placebo pill and the other group received a vitamin B supplement over 2 years. Cognitive performance was measured and the results compared with the results from the beginning of the study.
It was discovered that for individuals with low Omega-3 levels, the vitamin B supplements had virtually no effect. But for individuals with high Omega-3 levels, the B vitamins were effective in preventing cognitive decline in comparison to the placebo. This result corresponds with earlier findings that vitamin B supplements slow the rate of brain atrophy in mild cognitive impairment only in individuals with a good Omega-3 level to begin with.
The researchers also discovered that levels of DHA may be a bigger factor than levels of EPA. But they caution that more research is needed to determine whether this is true.
These results suggest that taking vitamin B supplements might only improve cognition in individuals who have high levels of Omega-3 oils. The results also suggest that for many older individuals a combination of fish oil and vitamin B supplements could help to improve memory and thinking.