Diabetes mellitus is one of the world's leading health problems, and standard approaches to therapy do not take into consideration the impact of circadian misalignment on metabolic health. Chronobiological processes are involved in regulating glucose homeostasis, insulin release, hepatic glucose production, lipids, and energy metabolism; hence, disruptions such as those caused by non-rhythmic sleep patterns, shifts at work, irregular meal times, and light exposure could cause insulin resistance and even type 2 diabetes. The current critical review discusses the light-melatonin interaction and personalized chronobiological medicine. Instead of giving a descriptive account of particular treatments, the paper introduces the integrative importance of chronobiology for the management of diabetes by considering data about chrononutrition, time-restricted feeding, chronopharmacology, chrono-exercise, and an approach to chronometabolism based on the integration of the timing of meals, drugs, exercise, sleep, and light exposure with chronotype, metabolic phenotype, and the feasibility of the therapy. Circadian timing can be a promising adjuvant in the treatment of diabetes; however, the available evidence does not suggest an ideal time for intervention. Further studies should focus on measuring time, well-powered randomized controlled trials, long-term outcomes, and individualization of chronotherapy.
