Docosahexaenoic acid (DHA) — an omega-3 fatty acid — can improve IQ by 10%, new research finds.
People in the study, who were aged over 65, were given 2g/day of DHA for a year.
A control group was given a placebo of corn oil.
The high quality study involved 240 Chinese individuals.
Their IQ and other measures of cognitive function were tested after 6 and 12 months.
The study’s authors explain the results:
“…oral DHA supplementation (2 g/d) for 12 months beneficially affected global cognitive function, specifically participants’ performance on the Information and Digit Span tasks.”
Brain scans also revealed changes in the hippocampus, an area of the brain critical for memory.
The study’s authors write:
“The hippocampus is a critical brain region for memory formation and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation.
Our results suggest that 12-month DHA supplementation significantly increased hippocampus volume.
Notably, we observed a 6.13% volume increase in the left hippocampus, a 1.89% increase in the right hippocampus, and a 0.29% increase in total hippocampus.
Best supplement combination?
The use of omega-3 to prevent dementia has provided some mixed results.
B vitamins also seem to be important in warding off cognitive decline.
A recent study found that B vitamins combined with omega-3 can help slow mental decline in older people with memory problems.
The study’s first author, Dr Abderrahim Oulhaj explained the results:
‘We found that for people with low levels of Omega-3, the vitamin supplements had little to no effect.
But for those with high baseline Omega-3 levels, the B vitamins were very effective in preventing cognitive decline compared to the placebo.
Other studies, though, have been less positive about the benefits of omega-3 for cognitive decline.
It is likely that the combination of nutrients — including both B vitamins and omega-3 will turn out to be the crucial factor.
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The study was published in the Journal of Alzheimer’s Disease (Zhang et al., 2016).