Cognitive boost: Study flags lutein’s potential in influencing memory performance

05 Aug 2019 --- Lutein, a carotenoid, may influence hippocampal-dependent memory performance, possibly via its antioxidant and anti-inflammatory effects. This is according to a University of Illinois, US, study, published in Nutrients. The study found that higher serum levels of lutein are linked to accuracy in object binding and inversely related to misplacement error.

The researchers note however that further research is warranted as this study does not establish a causal relationship between lutein and memory function.

Obesity has been associated with poorer cognitive function, including poorer hippocampal function. One potential mechanism related to both obesity and hippocampal function may be related to decreased intake and neural concentration of lutein – a carotenoid that accumulates in neural tissue at concentrations up to five times more than other carotenoids. 

In this cross-sectional study of 94 overweight or obese adults (aged 25-45), the researchers aimed to understand whether dietary, serum or macular levels of lutein and other carotenoids were associated with relational memory function. 

Relational memory is a hippocampal-dependent process that allows us to put a face with a name or retell a story in any order we choose. One way to assess relational memory is with a spatial reconstruction task, which requires participants to return objects to the locations they had previously seen them.

The study participants completed a computerized spatial reconstruction task to evaluate relational memory. They also received assessments for dietary intake of lutein, intelligence quotient (IQ), serum carotenoids, and retinal carotenoids.

The findings showed that serum beta-carotene and lutein as well as dietary beta-carotene and lutein + zeaxanthin correlated with memory performance. However, after adjusting for covariates, the only associations that remained significant were between serum lutein and two metrics of relational memory performance: serum lutein was positively correlated with accuracy in object binding and inversely related to misplacement error. 

Because of the cross-sectional design, this study cannot establish a causal relationship between lutein and memory function. Randomized controlled trials are needed to determine whether or not changes in lutein status induce changes in the hippocampal-dependent relational memory performance.

Edited by Kristiana Lalou