Lessons from the Voluntary Shawwal Fasting by People with Type 2 Diabetes: Individuals' Characteristics and Implications for Ramadan Fasting

Abstract Fasting during Ramadan for people with type 2 diabetes (T2D) can be challenging and may increase the risk of complications. Short period of voluntary fasting during Shawwal has not been studied. Its prevalence and characteristics remain unclear. We hypothesized that individuals who continue fasting into Shawwal represent a self-selected subgroup with greater fasting resilience and safer Ramadan experiences. We analyzed data from the 2020 and 2022 Diabetes and Ramadan (DAR) Global Surveys. Participants with T2D who fasted during Ramadan were divided into two groups: Group 1 (n = 2,845) continued fasting in Shawwal, and Group 2 (n = 6,536) did not. All variables in this analysis reflect only Ramadan experiences, including demographics, self-monitoring of blood glucose (SMBG), treatment use, and fasting-related complications. Findings were summarized descriptively to characterize Ramadan profiles associated with the intention to fast in Shawwal. Nearly one in three participants (30.3%) reported voluntary Shawwal fasting. Compared with Group 2, Group 1 participants were slightly older (55 ± 11.1 vs. 53.3 ± 11.6 years, p = 0.08) and had longer diabetes duration (12.3 ± 5.2 vs. 10.8 ± 4.9 years, p < 0.01). Hypertension (57.9 vs. 42.9%, p = 0.05) and hyperlipidemia (55.5 vs. 38.5%, p = 0.019) were more commonly reported in Group 1. During Ramadan, individuals who later fasted in Shawwal reported lower frequencies of recurrent hypoglycemia (7.3 vs. 12.1%, p = 0.01), fewer breaks in fasting due to hypoglycemia (50.4 vs. 61.1%, p = 0.03), and higher SMBG adherence (16.8 vs. 10.3%, p = 0.01). Hyperglycemia rates were similar between groups (15.2 vs. 14.3%, p = 0.7). These findings reflect experiences during Ramadan and do not represent Shawwal outcomes. Voluntary Shawwal fasting was reported by nearly one-third of individuals with T2D who had fasted during Ramadan. Those who intended to fast in Shawwal exhibited distinct Ramadan characteristics, including fewer reported hypoglycemia-related disruptions and slightly greater SMBG adherence. These descriptive observations likely reflect self-selection and prior Ramadan experiences rather than any effect of Shawwal fasting itself. Clinicians should acknowledge voluntary fasting practices such as Shawwal when counseling patients with T2D and reinforce individualized education and SMBG guidance.