1.
Impact of intermittent fasting on body weight in overweight and obese individuals.
Lima, CHR, Oliveira, IKF, Frota, KMG, Carvalho, CMRG, Paiva, AA, Campelo, V, Martins, MDCCE
Revista da Associacao Medica Brasileira (1992). 2020;(2):222-226
Abstract
OBJECTIVE To verify the relationship of intermittent fasting in the bodyweight of overweight and obese individuals through a systematic literature review. METHODS This is a systematic review based on randomized controlled trials. The articles were consulted in the databases: Science Direct, PubMed e BVS. This review was evaluated through the PRISMA recommendation. RESULTS After the selection process, four articles were included in this review, comparing intermittent fasting (IF) with calorie restriction diet (CRD) as a control group. In 2 studies using similar protocols, there was no significant reduction in body weight of overweight or obese subjects. In the other two studies using different protocols, weight loss was significant in the IF group compared to the CRD group. CONCLUSIONS Results did not provide evidence of the effect of intermittent fasting on weight loss in overweight or obese individuals.
2.
The role of intermittent fasting and meal timing in weight management and metabolic health.
Templeman, I, Gonzalez, JT, Thompson, D, Betts, JA
The Proceedings of the Nutrition Society. 2020;(1):76-87
Abstract
Obesity remains a major public health concern and intermittent fasting is a popular strategy for weight loss, which may present independent health benefits. However, the number of diet books advising how fasting can be incorporated into our daily lives is several orders of magnitude greater than the number of trials examining whether fasting should be encouraged at all. This review will consider the state of current understanding regarding various forms of intermittent fasting (e.g. 5:2, time-restricted feeding and alternate-day fasting). The efficacy of these temporally defined approaches appears broadly equivalent to that of standard daily energy restriction, although many of these models of intermittent fasting do not involve fed-fasted cycles every other 24 h sleep-wake cycle and/or permit some limited energy intake outside of prescribed feeding times. Accordingly, the intervention period therefore may not regularly alternate, may not span all or even most of any given day, and may not even involve absolute fasting. This is important because potentially advantageous physiological mechanisms may only be initiated if a post-absorptive state is sustained by uninterrupted fasting for a more prolonged duration than applied in many trials. Indeed, promising effects on fat mass and insulin sensitivity have been reported when fasting duration is routinely extended beyond sixteen consecutive hours. Further progress will require such models to be tested with appropriate controls to isolate whether any possible health effects of intermittent fasting are primarily attributable to regularly protracted post-absorptive periods, or simply to the net negative energy balance indirectly elicited by any form of dietary restriction.
3.
A systematic review, meta-analysis, and meta-regression of the impact of diurnal intermittent fasting during Ramadan on body weight in healthy subjects aged 16 years and above.
Jahrami, HA, Alsibai, J, Clark, CCT, Faris, MAE
European journal of nutrition. 2020;(6):2291-2316
Abstract
PURPOSE Studies on the effect of Ramadan diurnal intermittent fasting (RDIF) on body weight have yielded conflicting results. Therefore, we conducted a systematic review and meta-analysis to estimate the effect size of body weight changes in healthy, non-athletic Muslims practicing Ramadan fasting, and to assess the effect of covariates such as age, sex, fasting time duration, season, and country, using subgroup analysis, and meta-regression. Covariate adjustments were performed to explain the variability of weight change in response to Ramadan fasting. METHODS CINAHL, Cochrane, EBSCOhost, EMBASE, Google Scholar, ProQuest Medical, PubMed/MEDLINE, ScienceDirect, Scopus, and Web of Science databases were searched from date of inception in 1950 to the end of August 2019. RESULTS Eighty-five studies, conducted in 25 countries during 1982-2019, were identified. RDIF yielded a significant, but small reduction in body weight (K = 85, number of subjects, N = 4176 (aged 16-80 years), Hedges' g =- 0.360, 95% confidence interval (CI) - 0.405 to - 0.315, I2 = 45.6%), this effect size translates into difference in means of - 1.022 kg (95% CI - 1.164 kg to - 0.880 kg). Regression analysis for moderator covariates revealed that fasting time (min/day) is a significant (P < 0.05) moderator for weight change at the end of Ramadan, while age and sex are not. Variable effects for the season and country were found. CONCLUSION RDIF may confer a significant small reduction in body weight in non-athletic healthy people aged 16 years and above, directly associated with fasting time and variably correlated with the season, and country.