Effect of Various Types of Intermittent Fasting (IF) on Weight Loss and Improvement of Diabetic Parameters in Human

Abstract

Purpose of Review A number of recent studies have suggested that intermittent fasting is as effective as traditional calorie restriction (CR) for weight loss and for cardioprotection. However, it is still unclear whether IF improves diabetes risk indicators as does CR. This review provides an overview of various patterns of intermittent fasting and shows the effect of intermittent fasting on human anthropometric such as excess body weight and biochemical parameters for example high glucose and fasting insulin, which are risk factors for diabetes. Recent Findings There is a growing body of evidence pointing to the benefits of intermittent fasting for glucose and insulin homeostasis, but this should be confirmed by further studies in population groups with (or at high risk) type II diabetes and insulin resistance. Long-term studies are also needed that could reveal potential negative health effects that some studies report. Summary Eleven studies in overweight/obese adult people that included changes in weight, body composition, and diabetic parameters (fasting glucose, fasting insulin, HbA1c concentration, and HOMA-IR index) were published between 2012 and 2020. Seven studies concerning the effects of alternate day fasting (ADF) on weight loss and diabetic parameters were analyzed. All of them have shown the effects of ADF on weight loss and slight improvement in diabetic parameters. For time-restricted feeding (TRF), a significant improvement in the HOMA-IR index was observed in 2 studies. One study saw an increase in fasting glucose. An analysis of 2 studies using a complete alternate day fasting (CADF) was performed. One study showed decrease in fasting glucose and insulin, and in one a decrease in glycosylated hemoglobin (HbA1c) was observed. Conclusion Different types of intermittent fasting reduce body weight and reduce diabetes parameters such as fasting glucose, fasting insulin, HOMA-IR index, and glycated hemoglobin (HbA1c).

Intermittent Fasting and Metabolic Health

“…Calorie restriction (CR) is a reduction in total caloric intake that does not result in malnutrition. This has consistently been found to result in decreased body weight and increased longevity in many species, including non-human primates [15]. Among overweight humans, shortterm CR (6-months) has been shown to significantly improve multiple cardiovascular risk factors, insulin sensitivity, and mitochondrial function.…”

“…Likely due to these physiological changes, clinical trials indicate CR may have a number of beneficial effects among overweight adults, in addition to weight loss. However, over the past several decades, obesity intervention trials have revealed that the vast majority of individuals experience difficulties sustaining daily CR for extended periods of time [15].…”

“…Intermittent fasting has had increasing popularity as an alternative to continuous CR, with emerging data supporting promise in delivering similar benefits with respect to weight loss and cardiometabolic health. As opposed to traditional CR paradigms, IF is a only requires fasting for discrete periods of time [15].…”

“…Fasting could be on consecutive or nonconsecutive days in this method. Time restricted feed is another popular approach in which fasting occurs every day with variable hours, but usually the feeding occurs during a 6-h period with breakfast in the morning and dinner prior to 3 p.m., allowing for the duration of the fast to be 14-18 h [15,16]. These approaches and other less popular fasting approaches are shown in Table 1.…”

Impact of Dietary Restriction Regimens on Mitochondria, Heart, and Endothelial Function: A Brief Overview

“…Even though both dietary models can result in a decreased energy intake, the long-term adherence to CR is more difficult as compared with IF (Wegman et al, 2015 ; Lee et al, 2020 ). The most studied models of IF used CR on 2 days/week (5:2), alternate day energy restriction (energy restriction of 60–70% below estimated requirements) and time-restricted feeding (TRF) (timely restriction of calories intake during a specific time window during the day) (Nowosad and Sujka, 2021 ). Regardless of the model, IR and CR have been systematically associated with several beneficial effects in animal models and humans (Di Daniele et al, 2021 ).…”