Background / Objective: Historically, fasting has not only been practiced for medical but also for religious reasons. Bahá’ís follow an annual religious fast of 19 days. We assessed motivation behind and subjective health impacts of Bahá’í fasting. Methods: A convergent parallel mixed methods design was embedded in a clinical single arm observational study. Semi-structured interviews were conducted with six fasters before, during and after fasting. Three months after the fasting period, two focus group interviews were conducted. 146 Bahá’í volunteers answered an online survey at five time points before, during and after fasting. Results: Interviews: Fasting was found to play a central role for the religiosity of interviewees, implying changes in daily structures, spending time alone, engaging in religious practices, and experiencing social belonging. Results show an increase in mindfulness and well-being, accompanied by behavioural changes and experiences of self-efficacy and inner freedom. Survey: Scores point to an increase in mindfulness and well-being during fasting, while stress, anxiety and fatigue decreased. Mindfulness remained elevated even three months after the fast. Conclusion: Bahá'í intermittent dry fast seems to enhance participants’ mindfulness and well-being, lowering stress levels and reducing fatigue. Some of these effects lasted more than three months after fasting.