Investigating physiological glucose excursions before, during, and after Ramadan in adults without diabetes mellitus

AIM: The study aimed to investigate physiological effects of Ramadan fasting on continuously monitored glucose levels in relation to Ramadan in young non-diabetic adults.

METHODS: Continuous glucose monitoring was employed to measure interstitial glucose for several days 1-2weeks before Ramadan, in the middle of Ramadan, and 4-6weeks after Ramadan to assess glucose exposure and glucose variability.

RESULTS: A total of 34,182 accurate glucose sensor readings and 438 capillary blood glucose values [mean absolute difference median (interquartile range) 8.5 (6.9-11.1)%] were obtained from 18 non-diabetic adults [13 females; aged 24 (21-27) years; baseline body mass index 23.9 (20.6-28.9) kg/m2]. The continuous glucose monitoring profiles showed an increase in the hyperglycemic (above 140mg/dL) area under the curve after Ramadan compared to both before (P=0.004) and during Ramadan (P=0.003), along with an increased glucose variability after Ramadan (P=0.014). Both the area under the interstitial glucose concentration curve for the entire day and the average glucose were positively associated with body mass index during (P=0.004 and P=0.005, respectively) and after Ramadan (P=0.013 and P=0.01, respectively). Atypical continuous glucose patterns were recognized in 11% of subjects, distinguished by a prolonged increased glucose exposure, particularly in response to a meal.

CONCLUSION: The time-point 4-6weeks after Ramadan was distinguished by greater glucose exposure and wider glucose variability that may reflect ongoing changes in insulin sensitivity in response to altering lifestyle patterns in non-diabetic young adults across the spectrum of body weight.