Omega-3 LCPUFAs (Long-Chain Polyunsaturated Fatty Acids) and Reading: The Mediating Role of Auditory Processing and the Interactions Among PUFAs

Background: The present study aimed to clarify the neurocognitive processes through which blood levels of omega-3 LCPUFAs affect reading and writing abilities. Methods: A total of 74 school-age children whose reading and writing skills varied from normal to largely below normal underwent an assessment of reading and writing abilities, auditory and visual processing, phonological awareness, attention, and executive functions. Exploratory factor analysis extracted three neuropsychological factors whose roles as mediators between omega-3 LCPUFAs and reading/writing abilities were tested in GLM mediation models. The possible interactions with other PUFAs were further investigated. Results (on 73 participants): Omega-3 LCPUFA levels (EPA and DHA) correlated with reading and writing abilities and with the three extracted factors. Auditory–phonological processing skills were found to be significant mediators of the effect of PUFAs (especially EPA) on reading and writing abilities, whereas DHA and AA/ALA significantly moderated some of these effects. Conclusions: The link between omega-3 LCPUFAs and reading and writing abilities seems to be mediated mainly by the effects of LCPUFAs on auditory–phonological processing skills. These effects are especially linked to EPA, but they are modulated by DHA and AA/ALA levels. Hypotheses about possible molecular mechanisms at the basis of these effects are discussed.