The influence of dietary patterns on outcomes in a Bayesian choice task.

Background And Aims: Previous research has investigated the impact of diet on cognition, but the focus has often been on general cognition. This paper reports on a preregistered cross-sectional study aimed at testing for specific executive function differences across individuals who self-reported one of four distinct dietary patterns: , , , or pattern. Our hypotheses were aimed at testing whether adherence to a specialty diet improved decision making relative to those who reported following .

Methods: We administered an incentivized Bayesian choice task to all participants. The task involved multiple components of information-existing information (base rate odds) as well as new information (sample draw evidence)-to allow a test of how these information components were used in making probability assessments, and how this may differ by self-reported dietary pattern. Sample size, hypotheses, and analysis plans were all determined ex ante and registered on the Open Science Framework. Multi-variate linear and non-linear estimation methods were used to analyze the data.

Results: Our data failed to support our pre-registered hypotheses. In fact, we found some evidence that self-reported adherence to a specialty was associated with a reduced decision accuracy and was connected to an increased imbalance in how the participant weighted the two available sources of information when making choices.

Conclusion: Our results suggest that decision making is nuanced among dietary groups, but that short-term incentivized decisions in an ecologically valid field setting are likely not improved solely by following promoted dietary patterns such as the or diets.