The study, published in the Journal of Alzheimer's Disease, took place in Tianjin, China.
it was a randomized, double-blind, placebo-controlled trial in 240 (219 completed) Chinese individuals aged 65 and older with mild cognitive impairment.
The participants received either 2g/day of DHA or a corn oil placebo for 12 months and specific measures of cognitive function were measured at baseline, six months and 12 months.
The research team stated: “The potential benefits of DHA supplementation in people with mild cognitive impairment (MCI) have not been fully examined. Our study aimed to determine the effect of DHA supplementation on cognitive function and hippocampal atrophy in elderly subjects with MCI.”
The study results showed that there was a significant difference in the Full-Scale Intelligence Quotient (IQ) in the DHA group versus placebo, with IQ in the DHA group measuring 10% higher than the placebo group.
Additionally, there were statistically significant increases in two IQ sub-tests (Information and Digit Span). The Information and Digit Span subdomains are considered indicators of long-term and short-term memory, respectively.
The findings suggest that DHA supplementation of 2g/day for 12 months in MCI subjects can significantly improve cognitive function.
The study states: “The change in mean serum DHA levels was greater in the intervention group (+3.85%) compared to the control group (+1.06%). Repeated-measures analyses of covariance showed that, over 12 months, there was a significant difference in the Full-Scale Intelligence Quotient (ηp2 = 0.084; p = 0.039), Information (ηp2 = 0.439; p = 0.000), and Digit Span (ηp2 = 0.375; p = 0.000) between DHA-treated versus the placebo group.
“These findings suggest that DHA supplementation (2 g/day) for 12 months in MCI subjects can significantly improve cognitive function and slow the progression of hippocampal atrophy.”
While additional larger longer-term studies are needed to confirm the results, GOED Omega-3, the global organisation for EPA and DHA Omega-3, said this paper adds to the body of science supporting DHA omega-3s and their role in supporting cognitive function.
Source: Journal of Alzheimer's Disease
“Effects of DHA Supplementation on Hippocampal Volume and Cognitive Function in Older Adults with Mild Cognitive Impairment: A 12-Month Randomized, Double-Blind, Placebo-Controlled Trial”
Authors: Zhang, Yan-Ping, et al