Older adults with diets high in saturated and trans fatty acids may find a high intake of copper could produce an accelerated rate of decline in thinking, learning and memory abilities, reports the August issue of Archives of Neurology, a JAMA/Archives journal.
Martha Clare Morris, Sc.D., associate professor at the Institute for Healthy Aging at Rush University Medical Center, Chicago, and colleagues looked at 3,718 subjects age 65 years or older. Participants were tested for cognitive ability when the study began, then after three and six years. People involved filled out a questionnaire about their diets.
All subjects showed declining cognitive abilities as they aged. Overall, copper intake was not associated with the rate of change, but in those with the highest saturated- and trans-fat consumption, cognitive function deteriorated more rapidly the more copper they had in their diets. "The increase in rate for the high-fat consumers whose total copper intake was in the top 20% (greater than or equal to 1.6 mg per day) was equivalent to 19 more years of age," the study says.
The RDA of copper for adults is 0.9 mg per day. Several metals, including copper, zinc and iron, play an essential role in brain development and function; however, an imbalance in these might also affect the development of brain plaques associated with Alzheimer's disease. Iron and zinc were also assessed in this study, but the study did not find these metals have any effect on cognitive decline in tandem with a high-fat diet.
"This finding of accelerated cognitive decline among persons whose diets were high in copper and saturated and trans fats must be viewed with caution," the authors conclude. "The supporting evidence on this topic is limited. The strength of the association and the potential impact on public health warrant further investigation."
