Exploring Rates of Adherence and Barriers to Time-Restricted Eating

Intermittent fasting versus continuous caloric restriction for glycemic control and weight loss in type 2 diabetes: A traditional review

Type 2 Diabetes Mellitus (T2DM) represents a major global health issue, with its incidence anticipated to increase markedly in the forthcoming decades. Efficient non-pharmacological therapies, especially dietary approaches, are essential for regulating glycemic control and facilitating weight reduction. Intermittent Fasting (IF) and Continuous Caloric Restriction (CCR) are two well researched methodologies, but their relative effectiveness and enduring advantages continue to be topics of active discussion. This review systematically assesses and contrasts the impacts of intermittent fasting (IF) and continuous calorie restriction (CCR) on glycemic regulation and weight reduction in persons with type 2 diabetes mellitus (T2DM), highlighting their short-term and long-term effects, safety profiles, and adherence rates. A thorough literature analysis was performed utilizing PubMed and Google Scholar, concentrating on papers published from 2000 to 2024. The review encompassed randomized controlled trials and observational studies that investigated the effects of intermittent fasting (IF) and continuous calorie restriction (CCR) on glycemic indicators (HbA1c, fasting glucose) and body weight. IF shown substantial short-term advantages, encompassing marked decreases in HbA1c levels, fasting glucose, and body weight. Mechanistic discoveries emphasized better insulin sensitivity, augmented fat metabolism, and autophagy as key aspects. In contrast, CCR was linked to enduring metabolic enhancements, including decreased visceral fat and improved insulin sensitivity. Nevertheless, both dietary approaches demonstrated constraints.

Time-Restricted Eating is a Feasible Dietary Strategy in the Treatment of Complicated Type 2 Diabetes: The RESET2 Pilot Study

OBJECTIVE

To investigate the feasibility of a 12-week time-restricted eating (TRE) intervention targeting people with overweight/obesity and complicated type 2 diabetes to inform the design of a 1-year randomized controlled trial.

METHODS

In this single-arm pilot study, 20 participants with overweight/obesity and complicated type 2 diabetes were recruited from the diabetes clinics at Hvidovre Hospital and Steno Diabetes Center Copenhagen in the Greater Copenhagen area, Denmark. Participants followed 8 weeks of strict 10-hour TRE, followed by a 4-week TRE period with individual adjustments and support options.

RESULTS

Nineteen participants completed the intervention. Median (quartile 1-quartile 3) adherence to the eating window across all 12 weeks was 94% (86-98). Mean (95% confidence interval) reductions in body weight of -2.0 kg (-2.9 to -1.1) and hemoglobin A1c of -0.4% (-0.6 to -0.1) were observed. Participants expressed that the individualized options added flexibility to the eating concept, enabled the maintenance of social life, and eased challenging times with TRE.

CONCLUSIONS AND IMPLICATIONS

Twelve weeks of TRE was feasible. Individualized adjustments and support may have the potential to facilitate the maintenance of long-term TRE.

Maintenance of time-restricted eating and high-intensity interval training in women with overweight/obesity 2 years after a randomized controlled trial

Time-restricted eating (TRE) and high-intensity interval training (HIIT) improve cardiometabolic health in individuals with overweight/obesity, with high adherence rates in supervised settings. Long-term maintenance of TRE and HIIT in real-world settings is unknown. In our previous TREHIIT trial, 131 women (body mass index (BMI) ≥ 27 kg/m2) were randomized to 7 weeks of TRE (eating window 10-h/day), HIIT (3 sessions/week), a combination (TREHIIT), or no intervention (CON). We investigated self-reported continuation of TRE and/or HIIT after 2 years. Fifty-nine participants (39.0 years (standard deviation (SD) 6.1), BMI 30.7 kg/m2 (SD 4.2)) attended the follow-up. Of those who completed the 7-week TRE or HIIT intervention, 46% maintained TRE and 45% continued HIIT for 2 years. There were no statistically significant (at p < .01) between-group differences in cardiometabolic outcomes, but non-significant lower body mass in HIIT (-4.2 kg, 95% confidence interval (CI), -7.7 to -0.7, p = .019) and visceral fat in TREHIIT (-18 cm2, CI, -33 to -4, p = .015) versus CON. After 2 years, HIIT and TREHIIT had ~ 4 kg lower fat mass and ~ 20 cm² lower visceral fat (both p < .001) compared with baseline. A short-term TRE and HIIT intervention may promote long-term lifestyle changes and health benefits. Future studies should collect objective adherence data to understand long-term maintenance of TRE and HIIT.

Effect of Time-Restricted Eating on Sleep Quality and Body Composition: A Systematic Review

CONTEXT

Time-restricted eating (TRE) is a dietary approach that consolidates energy intake in a restricted period during the day. It is an alternative approach to weight loss and might be important to sleep quality.

OBJECTIVE

To review the current literature related to the effects of TRE on sleep quality and body composition in adults.

DATA SOURCES

A literature search of the PubMed, Scopus, Web of Science (Clarivate), and Biblioteca Virtual em Saúde/Bireme databases was carried out until May 2024.

DATA EXTRACTION

Reviewed articles included clinical, interventional (controlled or uncontrolled) studies including individuals older than 18 years, with no gender restriction. The interventions had to control feeding time, body composition could be assessed by any validated method, and sleep could be assessed by polysomnography, actigraphy, and validated sleep assessment questionnaires.

DATA ANALYSIS

Eleven studies were included in this systematic review. Study samples varied between 19 and 137 participants, with a predominance of female participants in 10 studies. Seven of the studies (58.3%) tested an intervention of 8 hours of TRE, with an intervention range of between 4 weeks and 12 months. All studies observed weight loss. Nine studies showed reductions in fat mass, including 2 studies that observed reductions in visceral fat mass. No studies, independently of weight loss or body composition changes, objectively observed changes in sleep duration after TRE interventions. However, in the subjective evaluation, 1 study found a reduction in sleep duration of 30 ± 13 minutes, an increase in latency of 7 ± 3 minutes, and a reduction in sleep efficiency of 2% ± 1% in the group treated with TRE compared with the control group.

CONCLUSION

Time-restricted eating seems to be effective in weight loss and fat mass reduction, but most studies found no effect on sleep parameters. There was a lack of standardized methods for sleep measurements in the reviewed studies. However, these results could provide valuable data for the design and formulation of new well-founded studies assessing sleep using objective methods and including different sleep parameters.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration No. CRD42024524598.

The effects of intermittent fasting on anthropometric indices, glycemic profile, chemotherapy-related toxicity, and subjective perception in gynecological and breast cancer patients: a systematic review and meta-analysis

BACKGROUND

Mounting evidence supports the health benefits of intermittent fasting (IF) in general. This study evaluates its impact on patients with gynecological or breast cancer specifically.

METHODS

A thorough search for studies comparing IF with either nonintervention diets or calorie restriction (CR) in patients with either gynecological or breast cancer and published prior to October 5, 2024 was carried out on the PubMed, Web of Science, Cochrane Library, Scopus, Embase, China National Knowledge Infrastructure (CNKI), and Chinese Biomedical Literature databases (CBM). Extracted data included but not limited to body mass index (BMI), body weight, waist circumference (WC), fasting glucose, insulin levels, chemotherapy-related toxicity, and subjective perceptions.

RESULTS

A total of 625 subjects were included across 7 randomized controlled trials, and 2 nonrandomized trials. Meta-analysis revealed that IF significantly reduced body weight (Effect Size [ES]: -0.611; 95% Confidence Interval [CI]: -0.886 to -0.356; p < 0.001; I² = 0%), blood glucose levels (standardized mean difference [SMD]: -0.347 mmol/L; 95% CI: -0.533 to -0.140; p < 0.001), and insulin concentrations (SMD: -0.395 mU/L; 95% CI: -0.674 to -0.116; p = 0.005). Sensitivity analysis indicated that the overall effect sizes were stable. However, it remains uncertain whether IF increases chemotherapy-related adverse effects (relative risk [RR]: 1.038; 95% CI: 0.844 to 1.278; p = 0.723). Furthermore, three studies indicated that IF reduced fatigue and two studies indicated that IF improved quality of life.

CONCLUSION

This systematic review and meta-analysis suggests that IF has a beneficial effect on reducing body weight, blood glucose, and insulin concentrations in gynecological and breast cancer patients. IF may also reduce fatigue and improve quality of life. However, the effect on chemotherapy-related adverse effects is uncertain. Further high-quality studies with long-term follow-ups are needed to confirm these findings.

Intermittent Fasting: Implications for Obesity-Related Colorectal Tumorigenesis

Obesity is associated with metabolic and immune perturbations (ie, insulin resistance, increased inflammation, and oxidative stress), circadian rhythm dysregulation, and gut microbial changes that can promote colorectal tumorigenesis. Colorectal cancer (CRC) is the third most incident cancer in the United States. This narrative review examines the effects of intermittend fasting on factors influencing colon tumorigenesis, such as body weight, metabolic and immune markers, circadian rythm, and the gut microbiota in humans. Findings suggest that intermittent fasting regimens can lead to weight loss and shifts in metabolic markers, which could be preventive for CRC but effects on the gut microbiota composition and functions still remains elusive.

The impact of intermittent energy restriction on women's health

Intermittent energy-restricted diets are used amongst women with overweight and obesity and a healthy weight. For those with overweight and obesity weight control is typically achieved through daily energy restriction (DER) which has reduced adherence and attenuated metabolic benefits over time. Several intermittent energy restriction (IER) regimens have been developed aiming to promote maintained weight loss and additional weight independent metabolic benefits including the 5:2 diet, alternate day fasting (ADF) and time-restricted eating (TRE). This review summarises the potential benefits or harms of these regimens for managing women’s health. 5:2 and ADF diets have equivalent long term (≥ 6-month) adherence, weight loss and metabolic benefits to DER. Current limited evidence suggests IER is a safe weight loss intervention for women which does not affect reproductive or bone health, increase eating disorders or disturb sleep. Adherence and weight loss with both IER and DER are lower amongst younger women compared to older women and men. Weight loss with ADF and TRE has, respectively, improved symptoms of polycystic ovarian syndrome and premenstrual syndrome, but there is no evidence of weight-independent effects of IER on these conditions. There is little evidence of the benefits and/or harms of IER amongst healthy weight women in whom there is a greater potential for adverse effects on reproductive and bone health, fat free mass, eating disorders and sleep. Further research benefits of IER for weight control and metabolic health as well as harms are required.

Time-Restricted Eating in Real-World Healthcare Settings: Utilisation and Short-Term Outcomes Evaluation

BACKGROUND

Time-restricted eating (TRE) shows promise for managing weight and metabolic issues, yet its application in real-world healthcare settings remains underexplored. This study aims to assess the real-world utilisation and short-term outcomes of TRE in clinical practice.

METHODS

This observational study used a retrospective chart review of 271 adults who attended a metabolic specialist clinic between 2019 and 2023. Descriptive statistics and multivariable logistic regression were used to identify factors associated with TRE adoption, while paired sample t-tests evaluated changes in outcomes among those who received TRE advice.

RESULTS

Among the 271 patients, 76% were female, 90% Caucasian, and 94% overweight/obese. Of all patients, 47.2% received TRE advice, mainly using the 16:8 method, alongside additional dietary guidance for 60% of patients. Working status and baseline metabolic profiles were the only factors significantly associated with TRE adoption. Among those who followed TRE, 81% experienced modest but significant reductions in weight (-1.2 kg, p < 0.01), BMI (-0.4 kg/m2, p < 0.01), and waist circumference (-3.7 cm, p < 0.01).

CONCLUSIONS

This study highlights TRE as a feasible and practical dietary strategy for improving metabolic health in healthcare settings. However, further research and improved data capture are needed to explore long-term adherence, potential adverse effects, and the effectiveness of TRE across diverse patient populations.

Comparing the effects of time-restricted eating on glycaemic control in people with type 2 diabetes with standard dietetic practice: A randomised controlled trial

AIMS

To test the efficacy of time-restricted eating (TRE) in comparison to dietitian-led individualised dietary guidance to improve HbA1c in people with Type 2 diabetes mellitus.

METHODS

In a parallel groups design, 51 adults (35-65 y) with Type 2 diabetes mellitus and overweight/obesity (HbA1c ≥6.5% (48 mmol/mol), BMI ≥25-≤40 kg/m2) commenced a six-month intervention. Following baseline, participants were randomised to TRE (1000-1900 h) or DIET (individualised dietetic guidance) with four consultations over four months. Changes in HbA1c (primary), body composition, and self-reported adherence (secondary) were analysed using linear mixed models. A non-inferiority margin of 0.3% (4 mmol/mol) HbA1c was set a priori.

RESULTS

Forty-three participants (56 ± 8 y, BMI: 33 ± 5 kg/m2, HbA1c: 7.6 ± 0.8%) completed the intervention. HbA1c was reduced (P=0.002; TRE: -0.4% (-5 mmol/mol), DIET: -0.3% (-4 mmol/mol)) with no group or interaction effects; TRE was non-inferior to DIET (-0.11%, 95%CI: -0.50% to 0.28%). Body mass reduced in both groups (TRE: -1.7 kg; DIET: -1.2 kg) via ∼900 kJ/d spontaneous energy reduction (P<0.001). Self-reported adherence was higher in TRE versus DIET (P<0.001).

CONCLUSIONS

When individualised dietary guidance is not available, effective, and/or suitable, TRE may be an alternative dietary strategy to improve glycaemic control in people with Type 2 diabetes mellitus.

Time-restricted eating improves health because of energy deficit and circadian rhythm: A systematic review and meta-analysis

Time-restricted eating (TRE) is an effective way to lose weight and improve metabolic health in animals. Yet whether and how these benefits apply to humans is unclear. This systematic review and meta-analysis examined the effect of TRE in people with overweight and obesity statuses. The results showed that TRE led to modest weight loss, lower waist circumference and energy deficits. TRE also improved body mass index, fat mass, lean body mass, systolic blood pressure, fasting glucose levels, fasting insulin levels, and HbA1c%. Subgroup analysis demonstrated more health improvements in the TRE group than the control group under the ad libitum intake condition than in the energy-prescribed condition. Eating time-of-day advantages were only seen when there was considerable energy reduction in the TRE group than the control group (ad libitum condition), implying that the benefits of TRE were primarily due to energy deficit, followed by alignment with eating time of day.