The Effect of Ramadan Intermittent Fasting on Cognitive Work Performance:

A Natural Experiment Approach


  • Ridwan Aji Budi Prasetyo Department of Psychology, Brawijaya University, Malang
  • Ratri Nurwanti Department of Psychology, Brawijaya University, Malang
  • Muhammad Afif Alhad Department of Psychology, Brawijaya University, Malang


intermittent fasting, natural experiment, cognitive performance, Ramadan


This study aims to investigate the effect of Ramadan intermittent fasting on cognitive work performance using a more natural approach. To achieve the objective of this study, a natural experimental approach was employed by incorporating a pretest-posttest control group design. A forward-type Digit Span Test (DST) was utilized as the measure of cognitive work performance and was administered to participants twice, before and during Ramadan, with a one-month gap between the tests. Two hundred and sixty-seven participants were naturally grouped into fasting and non-fasting groups according to their report during the Ramadan session and into morning and afternoon periods, or AM and PM hours, according to their module scheduling. The results of the analyses suggest that the cognitive work performance of the fasting participants during the PM hours is better, after controlling the DST scores before Ramadan. The study also concludes that the cognitive work performance of the fasting participants between AM and PM hours does not differ. This result could be explained using the perspectives of post-lunch performance dip and the beneficial effect of breakfast. Methodological limitations and the potential practical implementation of this study are also discussed.

Author Biographies

Ridwan Aji Budi Prasetyo, Department of Psychology, Brawijaya University, Malang

Department of Psychology, Brawijaya University

Human Factors & Engineering Psychology Lab, Brawijaya University

Ratri Nurwanti, Department of Psychology, Brawijaya University, Malang

Department of Psychology, Brawijaya University, Malang - Indonesia

Muhammad Afif Alhad, Department of Psychology, Brawijaya University, Malang

Department of Psychology, Brawijaya University, Malang - Indonesia


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How to Cite

R. A. B. Prasetyo, R. Nurwanti, and M. A. Alhad, “The Effect of Ramadan Intermittent Fasting on Cognitive Work Performance:: A Natural Experiment Approach”, Jurnal Teknik Industri: Jurnal Keilmuan dan Aplikasi Teknik Industri, vol. 26, no. 1, Mar. 2024.