Ramadan Diet Restrictions Modify the Circadian Time Structure in Humans. A Study on Plasma Gastrin, Insulin, Glucose, and Calcium and on Gastric pH¹

Abstract

The rule of Ramadan (1 month of food and water intakes restricted to night hours) is followed by the majority of the Moslem fraction of the human population, but the possible consequences of this long-lasting modification of food intake schedule on public health have not yet been extensively documented. Therefore, a group of healthy control subjects and a group of healed duodenal ulcer patients were studied before (controls), during (both groups), and after (both groups) the month of Ramadan. The time-restricted food and water intakes were associated with variations of gastric pH, plasma gastrin, insulin, glucose, and calcium documented on a circadian basis. All of the studied biological variables, except insulin, underwent changes in their 24-h mean concentration (e.g. decrease in gastric pH, increase in plasma gastrin), some of which were still present 1 month after the end of Ramadan. The circadian patterns of all the studied variables were altered during the month of Ramadan. Some differences between the group of healthy control subjects and the group of healed duodenal ulcer patients may suggest a greater susceptibility of the latter to the modifications of feeding and sleeping schedule, which could possibly be a risk factor for the disease.

Evaluation Of The Effect Of Fasting In Glaucoma Patients

“…Higher IOP values may be a result of a decline in the activity of the drug by 4 pm, when the effect of fasting becomes apparent. Secondly, habit modifications during Ramadan have been shown to affect the sleep cycle and circadian rhythms in several studies (16)(17)(18)(19). Bogdan et al (16) observed that during Ramadan the serum cortisol level increased in the afternoon; the ordinary morning rise was delayed.…”

Teaching Physical Education During Ramadan Observance: Practical Recommendations

“…Then, unlimited food intake and hydration are allowed till dawn. The obligation to eat only within a short overnight span leads to several behavioral changes in sleep (19,20), alertness (21), meal times (21,22) and eating schedule (21,22). Additionally, in adults, physiological changes may be observed during Ramadan observance such as dehydration (14,19,(23)(24)(25)(26)(27)(28)(29), metabolic responses (24,25,27,28) and the circadian variation of body temperature, cortisol and melatonin (30,31).…”

Impact of intermittent dietary restriction on the health-related outcomes of faith-based fasting

“…Several studies examined the health effects of making intermittent changes in mealtimes to accommodate the fasting requirements during Ramadan through sleep/wakefulness episodes. Findings from these studies showed that altered mealtimes, sleep patterns, and circadian rhythms were associated with increased risk factors for metabolic, endocrine, and gastrointestinal problems [27][28][29]. Clinical evidence demonstrated that an interrupted or restricted sleep pattern during the normal circadian nighttime cycle in Ramadan causes daytime fatigue, which has been associated with impaired cognitive and kinetic physical functioning [30].…”