Aims: This article aims to review and highlight the similarities and differences between time-restricted feeding and Islamic fasting during Ramadan.
Methods: A scoping review was undertaken to identify relevant articles that answered the research question: what are the similarities and differences in characteristics of time-restricted feeding and Islamic fasting? MEDLINE/PubMed was searched using the terms: time-restricted feeding, and weight. Inclusion criteria were: original research and review articles; written in English; and published between the years 2000 and 2017.
Results: A total of 25 articles that answered the research question were included in the review: 15 original research papers and 10 reviews. The findings suggest that Ramadan fasting is a form of time-restricted feeding in the contemporary context because of the period when eating is not allowed. The fasting duration reported in time-restricted feeding ranged from 4 to 24 hours, which is longer than that of Islamic fasting which is between 8 and 20 hours. Both time-restricted feeding and Islamic fasting have been found to have positive health effects, including weight reduction.
Conclusion: Time-restricted feeding and Islamic fasting have many similar characteristics and reported positive health effects.
METHODS: In this three-year longitudinal study, 125 subjects (77 PD patients and 48 spousal/sibling controls) underwent clinical, biochemical and body composition assessments using dual-energy X-ray absorptiometry.
RESULTS: Patients were older than controls (65.6 ± 8.9 vs. 62.6 ± 7.1, P = 0.049), with no significant differences in gender, comorbidities, dietary intake and physical activity. Clinically significant weight loss (≥5% from baseline weight) was recorded in 41.6% of patients, with a doubling of cases (6.5 to 13.0%) classified as underweight at study end. Over three years, patients demonstrated greater reductions in BMI (mean -1.2 kg/m2, 95%CI-2.0 to -0.4), whole-body fat percentage (-2.5% points, 95%CI-3.9 to -1.0), fat mass index (FMI) (-0.9 kg/m2, 95%CI-1.4 to -0.4), visceral fat mass (-0.1 kg, 95%CI-0.2 to 0.0), and subcutaneous fat mass (-1.9 kg, 95%CI-3.4 to -0.5) than in controls, with significant group-by-time interactions after adjusting for age and gender. Notably, 31.2% and 53.3% of patients had FMI<3rd (severe fat deficit) and <10th centiles, respectively. Muscle mass indices decreased over time in both groups, without significant group-by-time interactions. Multiple linear regression models showed that loss of body weight and fat mass in patients were associated with age, dyskinesia, psychosis and constipation.
CONCLUSIONS: We found progressive loss of weight in PD patients, with greater loss of both visceral and subcutaneous fat, but not muscle, compared to controls. Several associated factors (motor and non-motor disease features) were identified for these changes, providing insights on possible mechanisms and therapeutic targets.