Effect of Alternate-Day Fasting on Weight Loss, Weight Maintenance, and Cardioprotection Among Metabolically Healthy Obese Adults: A Randomized Clinical Trial

Impact of intermittent vs. continuous energy restriction on weight and cardiometabolic factors: a 12-month follow-up

BACKGROUND AND OBJECTIVE

Intermittent energy restriction continues to gain popularity as a weight loss strategy; however, data assessing it's long-term viability is limited. The objective of this study was to follow up with participants 12 months after they had completed a 12-month dietary intervention trial involving continuous energy restriction and two forms of intermittent energy restriction; a week-on-week-off energy restriction and a 5:2 programme, assessing long-term changes on weight, body composition, blood lipids and glucose.

SUBJECTS AND METHODS

109 overweight and obese adults, aged 18-72 years, attended a 12-month follow-up after completing a 12-month dietary intervention involving three groups: continuous energy restriction (1000 kcal/day for women and 1200 kcal/day for men), week-on-week-off energy restriction (alternating between the same energy restriction as the continuous group for one week and one week of habitual diet), or 5:2 (500 kcal/day on modified fast days each week for women and 600 kcal/day for men). The primary outcome was weight change at 24 months from baseline, with secondary outcomes of change in body composition, blood lipids and glucose.

RESULTS

For the 109 individuals who completed the 12-month follow-up (82 female, 15 male, mean BMI 33 kg/m²), weight decreased over time with no differences between week-on and week-off and continuous energy restriction or 5:2 and continuous energy restriction with -4.5 ± 4.9 kg for continuous energy restriction, -2.8 ± 6.5 kg for week-on, week-off and -3.5 ± 5.1 kg for 5:2. Total cholesterol reduced over time and glucose, HDL, LDL and triglycerides were unchanged.

DISCUSSION AND CONCLUSION

Intermittent energy restriction was as successful in achieving modest weight loss over a 24-month period as continuous energy restriction.

The Benefits of Fasting to Improve Health Conditions and to Prevent Cardiovascular Disease

Introduction: Fasting is defined as the voluntary abstinence from eating for variable time intervals and it has been associated with potential beneficial impacts on human health. The study was to review the benefits of fasting on cardiovascular health in humans with or without cardiovascular disease.Methods: The databases search was done using the keywords ‘fasting’ and ‘cardiovascular system’ using Scopus, Science Direct and ProQuest, limited to between 2013 and 2019 for publication year. A total of 3.619 articles were obtained and 15 articles involving experimental and non-experimental studies were used as the reference material.Results: The findings showed that in people who are healthy, fasting can reduce the inflammatory markers (IL-1 & IL-6, TNF-α), the oxidative stress marker (Malondialdehyde), body weight, abdominal circumference, fasting blood glucose, LDL, triglyceride and blood pressure. In people at risk or with cardiovascular disease, fasting can reduce body weight, body mass index, abdominal circumference, fat percentage, blood pressure, triglyceride, the biomarker of inflammation (serum amyloid A), the biomarker of oxidative stress (protein carbonyl), the biomarker of endothelial dysfunction (asymmetric dimethylarginine) and increase the vascular endothelial growth factor.Conclusion: Based on these findings, fasting can improve the health condition of people at risk or with cardiovascular disease by improving the risk factors such as blood pressure, overweight and endothelial dysfunction. In people who are healthy, fasting can be used for the prevention of cardiovascular disease by helping to maintain their weight, blood pressure, LDL and triglyceride within the normal limits.

Effects of fasting intervention regulating anthropometric and metabolic parameters in subjects with overweight or obesity: a systematic review and meta-analysis

Previous studies have shown that fasting produces a potential effect in the prevention and treatment of many diseases.

Dietary Restrictions and Nutrition in the Prevention and Treatment of Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of death in many developed countries and remains one of the major diseases strongly affected by the diet. Nutrition can affect CVD directly by contributing to the accumulation of vascular plaques and also indirectly by regulating the rate of aging. This review summarizes research on nutrition and CVD incidence based on a multipillar system that includes basic research focused on aging, epidemiological studies, clinical studies, and studies of centenarians. The relevant research linking nutrition and CVD with focus on macronutrients and aging will be highlighted. We will review some of the most relevant studies on nutrition and CVD treatment, also focusing on interventions known to delay aging. We will discuss both everyday dietary compositions, as well as intermittent and periodic fasting interventions with the potential to prevent and treat CVD.

Effects of alternate-day fasting on body weight and dyslipidaemia in patients with non-alcoholic fatty liver disease: a randomised controlled trial

Background

Alternate-day fasting (ADF) is a novel diet therapy that may achieve reduction in body weight and improvement of dyslipidaemia, but the impact of this diet on patients with non-alcoholic fatty liver disease (NAFLD) remains unknown. The aim of this study was to evaluate the effects of ADF on the body weight and lipid profile of individuals with NAFLD.

Methods

NAFLD patients (n = 271) were randomised to the ADF group, time-restricted feeding (TRF) group, or the control group and subjected to the respective diet for 12 weeks. Anthropometric measurements (body weight, fat mass/fat-free mass) were performed, and plasma lipids were analysed enzymatically.

Results

Within 4 weeks, the body weight decreased significantly (P < 0.001) in the ADF group by 4.56 ± 0.41 kg (6.1 ± 0.5%) and the TRF group by 3.62 ± 0.65 kg (4.83 ± 0.9%) compared to the control group, and it decreased even more after 12 weeks in both groups (ADF: − 4.04 ± 0.54 kg, 5.4 ± 0.7%; TRF: − 3.25 ± 0.67 kg, 4.3 ± 0.9%). Fat mass was significantly reduced by ADF (− 3.49 ± 0.37 kg; 11 ± 1.2%) and TRF (− 2.91 ± 0.41 kg; 9.6 ± 1.3%), with ADF leading to a further reduction in fat mass after 12 weeks (− 3.48 ± 0.38 kg; 11 ± 1.2%). Total cholesterol was significantly decreased at both time points in the ADF group (− 0.91 ± 0.07 mmol/L; 18.5 ± 1.5%) compared to the control and TRF groups. Both ADF (− 0.64 ± 0.06 mmol/L; 25 ± 1.9%) and TRF (0.58 ± 0.07 mmol/L; 20 ± 1.7%) achieved a significant reduction in serum triglycerides (P < 0.001) after 12 weeks. Changes in fat free mass, HDL, LDL, fasting insulin, glucose, liver stiffness, and systolic or diastolic blood pressure did not differ between the groups.

Conclusions

ADF appears to be an effective diet therapy for individuals with NAFLD that can achieve weight loss and improvement of dyslipidaemia within a relatively short period of time (4 to 12 weeks). Potential preventive effects of ADF on cardiovascular disease need to be confirmed by future investigations.

Trial registration

ChiCTR1900024411, this trial was retrospectively registered on July 10, 2019.

Alternate day fasting combined with a low-carbohydrate diet for weight loss, weight maintenance, and metabolic disease risk reduction

OBJECTIVE

Alternate day fasting (ADF) is a popular weight loss regimen. Whether carbohydrate restriction can enhance the weight loss achieved with ADF remains unclear. Accordingly, this study examined the effect of ADF combined with a low-carbohydrate diet on body weight and metabolic disease risk factors.

METHODS

Adults with obesity (n = 31) participated in ADF (600 kcal "fast day" alternated with an ad libitum "feast day") with a low-carbohydrate background diet (30% carbohydrates, 35% protein, and 35% fat). The 6-month trial consisted of a 3-month weight loss period followed by a 3-month weight maintenance period.

RESULTS

Body weight decreased (-5.5 ± 0.5%; P < .001) during the weight loss period (month 0-3) but remained stable (P = .57) during the weight maintenance period (month 4-6). Net weight loss by month 6 was -6.3 ± 1.0%. Fat mass was reduced (P < .01) by month 6, while lean mass and visceral fat mass remained unchanged. Total cholesterol and low-density lipoprotein (LDL) cholesterol levels decreased (P < .05) by -6 ± 2% and - 8 ± 3%, respectively, by month 6. Systolic blood pressure was also reduced (P = .03) by -7 ± 3 mm Hg. Fasting insulin decreased (P = .03) by -24 ± 8% by month 6 relative to baseline. High-density lipoprotein (HDL) cholesterol, triglycerides, diastolic blood pressure, heart rate, fasting glucose, homeostatic model assessment of insulin resistance (HOMA-IR), and haemoglobin A1C (HbA1c) remained unchanged.

CONCLUSIONS

These findings suggest that ADF combined with a low-carbohydrate diet is effective for weight loss, weight maintenance, and improving certain metabolic disease risk factors such as LDL cholesterol, blood pressure, and fasting insulin. While these preliminary findings are promising, they still require confirmation by a randomized control trial.

An Approach to Obesity Management for Gastroenterologists and Hepatologists

PURPOSE OF REVIEW

Obesity is associated with multiple gastrointestinal and liver diseases such as gastroesophageal reflux disease, Barrett's esophagus, esophageal adenocarcinoma, cholelithiasis, colon polyps, and fatty liver disease. To effectively manage obesity, it is imperative to understand current and emerging therapies and procedures.

FINDINGS

Obesity is becoming increasingly prevalent and is associated with a growing monetary health care burden. Cardiac disease, cerebrovascular disease, and diabetes are among the leading causes of preventable and premature death of Americans related to obesity. In addition to behavioral modification (diet and exercise) and bariatric surgery, multiple pharmacotherapies and endoscopic procedures are newly approved and available for the management of obesity. This paper reviews the current literature on the treatments available for the management of obesity including behavior modification, pharmacotherapy, endoscopic weight loss procedures (endobariatrics), and bariatric surgery.

Weight loss efficacy of alternate day fasting versus daily calorie restriction in subjects with subclinical hypothyroidism: a secondary analysis

This study compared the weight loss efficacy of alternate-day fasting (ADF) versus daily calorie restriction (CR) in adults with subclinical hypothyroidism. After 6 months, body weight decreased (P < 0.001) similarly by ADF (-7% ± 1%) and CR (-8% ± 2%). Insulin resistance decreased (P < 0.05) more by ADF versus CR. Free thyroxin and thyroid-stimulating hormone remained unchanged. Thus, ADF and CR produce similar weight loss in this population, without affecting thyroid hormone levels. Novelty Intermittent fasting and daily restriction produce similar reductions in body weight in subjects with subclinical hypothyroidism.

Weight Loss: How Does It Fit in With Liposuction?

BACKGROUND

Weight loss is traditionally viewed as straightforward counting of calories in and calories out, with little regard to the role of the adipocytes tasked with storing said calories. However, the body executes a complex compensatory response to any intervention that depletes its energy stores. Here, the authors discuss the methods used to attain weight loss, the body's response to this weight loss, and the difficulties in maintaining weight loss. Furthermore, the authors provide an overview of the literature on the physiological effects of liposuction.

OBJECTIVE

To describe the role of adipose tissue in energy homeostasis, methods of weight loss, weight regain, and the effect of liposuction on endocrine signaling.

METHODS

The authors conducted a narrative review of representative studies.

CONCLUSION

A variety of strategies for weight loss exist, and optimizing one's weight status may in turn optimize the aesthetic outcomes of liposuction. This is most apparent in the preferential reaccumulation of fat in certain areas after liposuction and the ability to avoid this with a negative energy balance.

Effectiveness of Intermittent Fasting and Time-Restricted Feeding Compared to Continuous Energy Restriction for Weight Loss

The current obesity epidemic is staggering in terms of its magnitude and public health impact. Current guidelines recommend continuous energy restriction (CER) along with a comprehensive lifestyle intervention as the cornerstone of obesity treatment, yet this approach produces modest weight loss on average. Recently, there has been increased interest in identifying alternative dietary weight loss strategies that involve restricting energy intake to certain periods of the day or prolonging the fasting interval between meals (i.e., intermittent energy restriction, IER). These strategies include intermittent fasting (IMF; >60% energy restriction on 2-3 days per week, or on alternate days) and time-restricted feeding (TRF; limiting the daily period of food intake to 8-10 h or less on most days of the week). Here, we summarize the current evidence for IER regimens as treatments for overweight and obesity. Specifically, we review randomized trials of ≥8 weeks in duration performed in adults with overweight or obesity (BMI ≥ 25 kg/m²) in which an IER paradigm (IMF or TRF) was compared to CER, with the primary outcome being weight loss. Overall, the available evidence suggests that IER paradigms produce equivalent weight loss when compared to CER, with 9 out of 11 studies reviewed showing no differences between groups in weight or body fat loss.

Efficacy of an intermittent energy restriction diet in a primary care setting

Purpose

Intermittent energy restriction (IER) is a popular weight loss (WL) strategy; however, its efficacy in clinical practice remains unknown. The present study compared the effects of IER compared to continuous energy restriction (CER) on WL and cardiometabolic risk factors in primary care.

Methods

A (self-selected) cohort study was conducted at the Rotherham Institute for Obesity (RIO), a primary care-based weight management service. 197(24% male) obese patients volunteered to participate and selected their diet group. IER participants (n = 99) consumed ~ 2600 kJ for two days/week. CER participants (n = 98) restricted their diet by ~ 2100 kJ/day below estimated requirements. Both interventions were delivered alongside RIO standard care. Changes in anthropometry and cardiometabolic disease risk markers (fasting biochemistry and blood pressure) were assessed after a 6-month intervention period and then participants were followed up again 6 months later (month 12).

Results

27 IER patients (27%) and 39 CER patients (40%) completed the 6-month weight loss phase. Among completers, mean (SEM) WL was greater in the IER group at 6 months (5.4 ± 1.1% versus 2.8 ± 0.6%; p = 0.01), as were reductions in fat mass (p < 0.001) and improvements in systolic blood pressure (p < 0.001). Fasting insulin (p = 0.873) and diastolic blood pressure (p = 0.701) were reduced similarly in both groups. However, in the IER group, changes in anthropometry and blood pressure in the IER group had reverted to baseline by 12-month follow-up, whilst the CER group maintained weight loss but showed an increase in blood pressure.

Conclusions

Among completers, IER resulted in superior short-term changes in anthropometry and some cardiometabolic risk factors. However, rates of attrition and weight regain were higher compared with standard care, providing important insights in the implementations of IER within a “real-life” NHS setting.

Trial registration number

ISRCTN31465600.

Electronic supplementary material

The online version of this article (10.1007/s00394-019-02098-y) contains supplementary material, which is available to authorized users.

Nutrients in the Prevention of Alzheimer's Disease

Alzheimer's disease (AD) is a disease caused by the complex interaction of multiple mechanisms, some of which are still not fully understood. To date, pharmacological treatments and supplementation of individual nutrients have been poorly effective in terms of the prevention and treatment of AD, while alternative strategies based on multimodal approaches (diet, exercise, and cognitive training) seem to be more promising. In this context, the focus on dietary patterns rather than on single food components could be more useful in preventing or counteracting the pathological processes typical of AD, thanks to the potential synergistic effects of various nutrients (neuronutrients). The aim of this narrative review is to summarize the currently existing preclinical and clinical evidence regarding the Mediterranean diet (MeDi), the Dietary Approaches to Stop Hypertension (DASH) diet, and the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, which are three dietary patterns with well-known anti-inflammatory and antioxidant properties. Recently, they have been related to brain protection and AD prevention, perhaps thanks to their high content of neuroprotective bioactive compounds. Similarly, intermittent fasting (IF) or calorie restriction (CR) is emerging as interesting approaches that seem to promote hippocampal neurogenesis, activate adaptive stress response systems, and enhance neuronal plasticity, thus leading to motor and cognitive improvements in animal models of AD and hopefully also in human beings.

Alternate-Day Fasting Gets a Safe Bill of Health

Various forms of fasting improve health and longevity in preclinical models. However, safety, outcomes, and the molecular changes underpinning human fasting are unclear. Stekovic et al. (2019) report improved markers of health for up to 6 months and associated metabolic changes among healthy adults who followed alternate-day fasting.

Alternate Day Fasting Improves Physiological and Molecular Markers of Aging in Healthy, Non-obese Humans

Caloric restriction and intermittent fasting are known to prolong life- and healthspan in model organisms, while their effects on humans are less well studied. In a randomized controlled trial study (ClinicalTrials.gov identifier: NCT02673515), we show that 4 weeks of strict alternate day fasting (ADF) improved markers of general health in healthy, middle-aged humans while causing a 37% calorie reduction on average. No adverse effects occurred even after >6 months. ADF improved cardiovascular markers, reduced fat mass (particularly the trunk fat), improving the fat-to-lean ratio, and increased β-hydroxybutyrate, even on non-fasting days. On fasting days, the pro-aging amino-acid methionine, among others, was periodically depleted, while polyunsaturated fatty acids were elevated. We found reduced levels sICAM-1 (an age-associated inflammatory marker), low-density lipoprotein, and the metabolic regulator triiodothyronine after long-term ADF. These results shed light on the physiological impact of ADF and supports its safety. ADF could eventually become a clinically relevant intervention.

Beverage intake during alternate-day fasting: Relationship to energy intake and body weight

BACKGROUND

Alternate-day fasting (ADF) involves a 'famine day' (25% energy intake) and a 'feast day' (ad libitum intake). This secondary analysis examined changes in beverage intake in relation to energy intake and body weight during 12 months of ADF versus daily calorie restriction (CR).

METHODS

Obese subjects (n = 100 enrolled, n = 69 completers) were randomized to one of three groups for 12 months: (a) ADF; (b) CR; or (c) control.

RESULTS

At baseline, intakes of diet soda, caffeinated beverages, sugar-sweetened soda, alcohol, juice, and milk were similar between groups. There were no statistically significant changes in the intake of these beverages by month 6 or 12 between ADF (feast or famine day), CR, or control groups. Beverage intake was not related to energy intake or body weight at month 6 or 12 in any group.

CONCLUSION

These pilot findings suggest that intermittent fasting does not impact beverage intake in a way that affects energy intake or body weight.

Alternate-day feeding leads to improved glucose regulation on fasting days without significant weight loss in genetically obese mice

Alternate-day fasting (ADF) is effective for weight loss and increases insulin sensitivity in diet-induced obese rodents. However, the efficacy of ADF in genetic models of obesity has not been comprehensively studied. Mice that are deficient in leptin ( ob/ob mice) are obese, diabetic, and prone to deep bouts of torpor when fasted. We tested the hypotheses that an ADF protocol in ob/ob mice would result in 1) induction of torpor on fasted days, 2) minimal body weight loss if the mice experienced torpor, and 3) no improvement in glucose control in the absence of weight loss. Female ob/ob mice and littermate controls were assigned to 1) an ad libitum regimen or 2) an ADF regimen, consisting of fasting every other day with ad libitum feeding between fasts. Over a 19-day period, littermate control mice on the ADF regimen consumed the same amount of food as littermate control mice on the ad libitum regimen, whereas the ADF ob/ob mice consumed 37% less food than ad libitum ob/ob mice. Fasting days, but not fed days, led to torpor in both genotypes. Fasting days, but not fed days, led to weight loss in both genotypes relative to ad libitum controls. Fasting days, but not fed days, produced enhanced insulin sensitivity in both genotypes and normalized circulating glucose in ob/ob mice. These data demonstrate improved glucose control on fasting days with the use of ADF in a genetic model of obesity in the face of minimal weight loss.

Differential Effects of Alternate-Day Fasting Versus Daily Calorie Restriction on Insulin Resistance

OBJECTIVE

This study compared the effects of alternate-day fasting (ADF) with those of daily calorie restriction (CR) on body weight and glucoregulatory factors in adults with overweight or obesity and insulin resistance.

METHODS

This secondary analysis examined the data of insulin-resistant individuals (n = 43) who participated in a 12-month study that compared ADF (25% energy needs on "fast days"; 125% energy needs on alternating "feast days") with CR (75% energy needs every day) and a control group regimen.

RESULTS

In insulin-resistant participants, weight loss was not different between ADF (-8% ± 2%) and CR (-6% ± 1%) by month 12, relative to controls (P < 0.0001). Fat mass and BMI decreased (P < 0.05) similarly from ADF and CR. ADF produced greater decreases (P < 0.05) in fasting insulin (-52% ± 9%) and insulin resistance (-53% ± 9%) compared with CR (-14% ± 9%; -17% ± 11%) and the control regimen by month 12. Lean mass, visceral fat mass, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, blood pressure, C-reactive protein, tumor necrosis factor α, and interleukin 6 values remained unchanged.

CONCLUSIONS

These findings suggest that ADF may produce greater reductions in fasting insulin and insulin resistance compared with CR in insulin-resistant participants despite similar decreases in body weight.

Fad Diets: Hype or Hope?

PURPOSE OF REVIEW

Obesity continues to be a growing concern globally due to association with a number of comorbidities and contributing significantly to increase in health care expenditures. Despite availability of a number of treatment modalities, lifestyle modification with dietary modification and exercise continues to be the foundation. However, the standard model of lifestyle modification is not efficacious or sustainable for many patients leading them to seek alternative approaches. We conducted a comprehensive literature review to present the data regarding efficacy and sustainability of many common dietary approaches.

RECENT FINDINGS

Building upon previous work, recent randomized controlled trials have compared many popular diets head to head in varying patient populations. Along with the weight changes, studies have investigated the changes in metabolic parameters, inflammatory markers, and cardiac risk factor reduction. Though the studies do not show superiority of one diet compared to the other, the preventive benefits and other favorable metabolic changes of the diets make them worthy of consideration.

Intermittent energy restriction is comparable to continuous energy restriction for cardiometabolic health in adults with central obesity: A randomized controlled trial; the Met-IER study

BACKGROUND & AIMS

Short bouts of severe energy restriction may have additional, beneficial cardiometabolic effects beyond that of weight loss. We aimed to assess the short-term effects of intermittent fasting on insulin sensitivity and related cardiometabolic mechanisms.

METHODS

This parallel arm, randomized controlled trial compared the short-term effects of intermittent and continuous energy restriction (IER and CER) diets on markers of cardiometabolic health in individuals with central obesity, aiming for equivalent weight loss on both diets. Outcomes were assessed in non-smoking men and women (35-75 y), following 4-wk IER (48 h 600 kcal/d followed by 5-day healthy eating advice) or CER diets (-500 kcal/d healthy eating advice). The primary outcome was the revised quantitative insulin sensitivity check index (R-QUICKI), an indirect estimate of insulin sensitivity. Secondary outcomes included ambulatory blood pressure (ABP), indicators of sympathetic activity (heart rate variability (HRV) and normetanephrine), and markers of glucose homeostasis/insulin resistance, adiposity, lipids and inflammation.

RESULTS

Forty-three participants completed the study. Reductions in body weight were equivalent in both groups: mean loss (%) -2.6; 95% CI -3.3, -1.9 and -2.9; -3.6, -2.1 for CER and IER, respectively, P = 0.464). R-QUICKI increased following IER and CER, with no between-diet differences (overall mean increase (%) 6.6; 3.6, 9.6). Fasting plasma glucose concentrations decreased after CER but not after IER (mean difference CER-IER - 4.8% (0.7, 8.9), P < 0.05) and fasting plasma non-esterified fatty acid concentrations were lower after IER compared to CER (mean difference CER-IER 0.15 mmol/L (0.06, 0.24), P < 0.005). There were no differences in lipids, adipokine/inflammatory markers, ABP or HRV between diets.

CONCLUSIONS

Short-term CER or IER diets are comparable in their effects on most markers of cardiometabolic risk, although adaptive changes in glucose and fatty acid metabolism occur. This study is registered at clinicaltrials.gov as NCT02679989.

Markers of adipose tissue inflammation are transiently elevated during intermittent fasting in women who are overweight or obese

OBJECTIVE

This study compared the effects of daily calorie restriction (DR) versus intermittent fasting (IF) on markers of inflammation and extracellular matrix deposition in adipose tissue and skeletal muscle in a controlled feeding trial in women with overweight or obesity.

METHODS

Women (N = 76) were randomised to one of three diets and provided with all foods at 100% (IF100) or 70% (IF70 and DR70) of calculated energy requirements for 8 weeks. IF groups ate breakfast prior to fasting for 24-h on 3 non-consecutive days/week. Weight, body composition, serum non-esterified fatty acids (NEFA), tumour necrosis factor-alpha (TNFα), interleukin-6 (IL-6), interleukin-10 (IL-10), M1- and M2-macrophage markers by qPCR and immunohistochemistry in adipose tissue and skeletal muscle were measured following a 12-h overnight fast (fed day, all groups) and a 24-h fast (IF groups only).

RESULTS

IF70 resulted in greater weight and fat losses and reductions in serum NEFA versus DR70 and IF100 (P < 0.05) after fed days. Markers of inflammation in serum (TNFα, IL6 and IL10), subcutaneous adipose tissue and skeletal muscle (CD68, CD40 and CD163) were unchanged by DR or IF after fed days. After fasting, NEFA, M1-macrophages (CD40⁺) in adipose tissue, and M2-macrophages (CD163⁺) in muscle were increased in IF70 and IF100 (all P < 0.05) and the changes in NEFA and mRNA of pan-macrophage marker CD68 in adipose tissue were positively correlated (r = 0.56, P = 0.002).

CONCLUSIONS

Unlike caloric restriction, IF transiently elevated markers of macrophage infiltration in adipose tissue and skeletal muscle, possibly in response to marked increases in adipose tissue lipolysis.

The role of intermittent fasting and meal timing in weight management and metabolic health

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.

Clinical Management of Intermittent Fasting in Patients with Diabetes Mellitus

Intermittent fasting is increasing in popularity as a means of losing weight and controlling chronic illness. Patients with diabetes mellitus, both types 1 and 2, comprise about 10% of the population in the United States and would likely be attracted to follow one of the many methods of intermittent fasting. Studies on the safety and benefits of intermittent fasting with diabetes are very limited though, and health recommendations unfortunately today arise primarily from weight loss gurus and animal studies. Medical guidelines on how to manage therapeutic intermittent fasting in patients with diabetes are non-existent. The evidence to build such a clinical guideline for people with a diabetes diagnosis is almost non-existent, with just one randomized trial and several case reports. This article provides an overview of the available knowledge and a review of the very limited pertinent literature on the effects of intermittent fasting among people with diabetes. It also evaluates the known safety and efficacy issues surrounding treatments for diabetes in the fasting state. Based on those limited data and a knowledge of best practices, this paper proposes expert-based guidelines on how to manage a patient with either type 1 or 2 diabetes who is interested in intermittent fasting. The safety of each relevant pharmaceutical treatment during a fasting period is considered. When done under the supervision of the patient’s healthcare provider, and with appropriate personal glucose monitoring, intermittent fasting can be safely undertaken in patients with diabetes.

Clinical Management of Intermittent Fasting in Patients with Diabetes Mellitus

Intermittent fasting is increasing in popularity as a means of losing weight and controlling chronic illness. Patients with diabetes mellitus, both types 1 and 2, comprise about 10% of the population in the United States and would likely be attracted to follow one of the many methods of intermittent fasting. Studies on the safety and benefits of intermittent fasting with diabetes are very limited though, and health recommendations unfortunately today arise primarily from weight loss gurus and animal studies. Medical guidelines on how to manage therapeutic intermittent fasting in patients with diabetes are non-existent. The evidence to build such a clinical guideline for people with a diabetes diagnosis is almost non-existent, with just one randomized trial and several case reports. This article provides an overview of the available knowledge and a review of the very limited pertinent literature on the effects of intermittent fasting among people with diabetes. It also evaluates the known safety and efficacy issues surrounding treatments for diabetes in the fasting state. Based on those limited data and a knowledge of best practices, this paper proposes expert-based guidelines on how to manage a patient with either type 1 or 2 diabetes who is interested in intermittent fasting. The safety of each relevant pharmaceutical treatment during a fasting period is considered. When done under the supervision of the patient’s healthcare provider, and with appropriate personal glucose monitoring, intermittent fasting can be safely undertaken in patients with diabetes.

Intermittent Fasting in Cardiovascular Disorders-An Overview

Intermittent fasting is a form of time restricted eating (typically 16 h fasting and 8 h eating), which has gained popularity in recent years and shows promise as a possible new paradigm in the approach to weight loss and the reduction of inflammation, and has many potential long term health benefits. In this review, the authors will incorporate many aspects of fasting, mainly focusing on its effects on the cardiovascular system, involving atherosclerosis progression, benefits for diabetes mellitus type 2, lowering of blood pressure, and exploring other cardiovascular risk factors (such as lipid profile and inflammation).

Obesity

The role of internists in evaluating obesity is to assess the burden of weight-related disease, mitigate secondary causes of weight gain (medications, sleep deprivation), and solicit patient motivation for weight loss. Internists should assess these factors and emphasize the importance of weight loss for the individual patient. All patients wishing to lose weight should be encouraged to monitor their diet and physical activity and should be referred to high-intensity behavioral programs. Some patients with obesity may also benefit from pharmacotherapy or bariatric surgery.

Dietary modifications for weight loss and weight loss maintenance

Worldwide obesity rates remain at a rise, and to treat obesity is at the top of the global public health agenda. In 2013, the AHA/ACC/TOS obesity management guidelines were published, in essence suggesting that any dietary scheme seems to be effective for weight loss, as long as it can induce a sustainable energy deficit. In the present review, we update and critically discuss available information regarding dietary modifications for weight loss and weight loss maintenance, published after the 2013 guidelines. Regarding weight loss, we found no proof to support that a single dietary scheme, be it nutrient-, food group- or dietary pattern- based, is more efficacious of the other for achieving weight loss. For weight loss maintenance, published interventions point towards the same direction, although inconclusively. Most research explores the effect of weight loss regimes on weight loss maintenance and not the effect of the diet during weight loss maintenance, and this literature gap should be more thoroughly investigated.

β-Hydroxy β-methylbutyrate free acid alters cortisol responses, but not myofibrillar proteolysis, during a 24-h fast

This study was a randomised, double-blind, placebo-controlled cross-over trial examining the effects of β-hydroxy β-methylbutyrate free acid (HMB-FA) supplementation on muscle protein breakdown, cortisol, testosterone and resting energy expenditure (REE) during acute fasting. Conditions consisted of supplementation with 3 g/d HMB-FA or placebo during a 3-d meat-free diet followed by a 24-h fast. Urine was collected before and during the 24-h fast for analysis of 3-methylhistidine:creatinine ratio (3MH:CR). Salivary cortisol, testosterone, their ratio (T:C), and the cortisol awakening response were assessed. ANOVA was used to analyse all dependent variables, and linear mixed models were used to confirm the absence of carryover effects. Eleven participants (six females, five males) completed the study. Urinary HMB concentrations confirmed compliance with supplementation. 3MH:CR was unaffected by fasting and supplementation, but the cortisol awakening response differed between conditions. In both conditions, cortisol increased from awakening to 30 min post-awakening (P=0·01). Cortisol was reduced from 30 to 45 min post-awakening with HMB-FA (-32 %, d=-1·0, P=0·04), but not placebo (PL) (-6 %, d=-0·2, P=0·14). In males, T:C increased from 0 to 24 h of fasting with HMB-FA (+162 %, d=3·0, P=0·001), but not placebo (+13 %, d=0·4, P=0·60), due to reductions in cortisol. REE was higher at 24 h of fasting than 16 h of fasting independent of supplementation (+4·0 %, d=0·3, P=0·04). In conclusion, HMB-FA may affect cortisol responses, but not myofibrillar proteolysis, during acute 24-h fasting.

A Comparison of Dietary and Caloric Restriction Models on Body Composition, Physical Performance, and Metabolic Health in Young Mice

Time-restricted feeding (TRF), alternate day fasting (ADF), and the dietary restriction model known as the Daniel Fast (DF; a vegan/non-processed food diet plan) have garnered attention recently as nutritional interventions to combat obesity. We compared the effects of various dietary models on body composition, physical performance, and metabolic health in C57BL/6 mice. Sixty young C57BL/6 male mice were assigned a diet of TRF, ADF, DF, caloric restriction (CR), a high-fat Western diet (HF) fed ad libitum, or standard rodent chow for eight weeks. Their body composition, run time to exhaustion, fasting glucose, insulin, and glucose tolerance test area under the glucose curve (AUC) were determined. Compared to the HF group, all groups displayed significantly less weight and fat mass gain, as well as non-significant changes in fat-free mass. Additionally, although not statistically significant, all groups displayed greater run time to exhaustion relative to the HF group. Compared to the HF group, all groups demonstrated significantly lower fasting glucose, insulin, and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), as well as improved glucose tolerance, and the ADF group displayed the best fasting glucose and glucose tolerance results, with DF having the best HOMA-IR. All investigated fasting protocols may improve body composition, measures of insulin sensitivity, and physical performance compared to a high-fat Western diet. The DF and ADF protocols are most favorable with regards to insulin sensitivity and glucose tolerance. Since our selected dietary protocols have also been investigated in humans with success, it is plausible to consider that these dietary models could prove beneficial to men and women seeking improved body composition and metabolic health.

Fasting Physiology and Therapeutic Diets: A Look Back to the Future

The evidence presented at this event demonstrated the multiple clinical benefits of fasting physiology and points toward a future in which the clinical applications of dietary approaches will be well understood and successfully utilized. The conference reflected the scope and breadth of current research efforts in this important clinical area. Clearly, the application of the important new concepts related to fasting physiology that are emerging will require the advocacy and participation of professionals who are well trained in the fields of clinical nutrition and personalized lifestyle medicine.

Pilot Study of Novel Intermittent Fasting Effects on Metabolomic and Trimethylamine N-oxide Changes During 24-hour Water-Only Fasting in the FEELGOOD Trial

Intermittent fasting (IF) has been connected with health benefits such as weight loss, lower risk of coronary artery disease (CAD) and diabetes, increased longevity, and improved quality of life. However, the mechanisms of these IF benefits in humans require further investigation. This study sought to elucidate some of these mechanisms through secondary analyses of the Fasting and ExprEssion of Longevity Genes during fOOD abstinence (FEELGOOD) trial, in which apparently healthy participants were randomized in a Latin square design to a 24-h water-only fast and a 24-h ad libitum fed day. Two pathways were investigated, with trimethylamine N-oxide (TMAO) levels measured due to their association with elevated risk of CAD, along with conductance of a broad panel of metabolic analytes. Measurements were made at baseline, at the end of the fasting day, and at the end of the fed day. A fasting mean of 14.3 ng in TMAO was found versus the baseline mean of 27.1 ng with p = 0.019, although TMAO levels returned to baseline on refeeding. Further, acute alterations in levels of proline, tyrosine, galactitol, and urea plasma levels were observed along with changes in 24 other metabolites during the fasting period. These acute changes reveal short-term mechanisms which, with consistent repeated episodes of IF, may lead to improved health and reduced risk of CAD and diabetes.

Intermittent Dieting: Theoretical Considerations for the Athlete

Athletes utilise numerous strategies to reduce body weight or body fat prior to competition. The traditional approach requires continuous energy restriction (CER) for the entire weight loss phase (typically days to weeks). However, there is some suggestion that intermittent energy restriction (IER), which involves alternating periods of energy restriction with periods of greater energy intake (referred to as ‘refeeds’ or ‘diet breaks’) may result in superior weight loss outcomes than CER. This may be due to refeed periods causing transitory restoration of energy balance. Some studies indicate that intermittent periods of energy balance during energy restriction attenuate some of the adaptive responses that resist the continuation of weight and fat loss. While IER—like CER—is known to effectively reduce body fat in non-athletes, evidence for effectiveness of IER in athletic populations is lacking. This review provides theoretical considerations for successful body composition adjustment using IER, with discussion of how the limited existing evidence can be cautiously applied in athlete practice.

Effects of Intermittent Versus Continuous Energy Intakes on Insulin Sensitivity and Metabolic Risk in Women with Overweight

OBJECTIVE

This study aimed to compare intermittent fasting (IF) versus continuous energy intakes at 100% or 70% of calculated energy requirements on insulin sensitivity, cardiometabolic risk, body weight, and composition.

METHODS

Women with overweight (n = 88; 50 ± 1 years, BMI 32.3 ± 0.5 kg/m² ) were randomized to one of four diets (IF70, IF100, dietary restriction [DR70], or control) in a 2:2:2:1 ratio for 8 weeks. IF groups fasted for 24 hours after breakfast on three nonconsecutive days per week. All foods were provided and diets matched for macronutrient composition (35% fat, 15% protein, 50% carbohydrate). Insulin sensitivity by hyperinsulinemic-euglycemic clamp, weight, body composition, and plasma markers were assessed following a "fed" day (12-hour fast) and a 24-hour fast (IF only).

RESULTS

IF70 displayed greater reductions in weight, fat mass, total- and low-density lipoprotein cholesterol, and nonesterified fatty acids compared with DR70 and IF100 (all P ≤ 0.05). IF100 lost more weight and fat than control. However, fasting insulin was increased. There were no group differences in insulin sensitivity by clamp; however, a 24-hour fast transiently reduced insulin sensitivity.

CONCLUSIONS

When prescribed at matched energy restriction, IF reduced weight and fat mass and improved total and low-density lipoprotein cholesterol more than DR. IF prescribed in energy balance did not improve health compared with other groups, despite modest weight loss.

Intermittent versus continuous energy restriction on weight loss and cardiometabolic outcomes: a systematic review and meta-analysis of randomized controlled trials

Background

This systematic review and meta-analysis summarized the most recent evidence on the efficacy of intermittent energy restriction (IER) versus continuous energy restriction on weight-loss, body composition, blood pressure and other cardiometabolic risk factors.

Methods

Randomized controlled trials were systematically searched from MEDLINE, Cochrane Library, TRIP databases, EMBASE and CINAHL until May 2018. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI).

Results

Eleven trials were included (duration range 8–24 weeks). All selected intermittent regimens provided ≤ 25% of daily energy needs on “fast” days but differed for type of regimen (5:2 or other regimens) and/or dietary instructions given on the “feed” days (ad libitum energy versus balanced energy consumption). The intermittent approach determined a comparable weight-loss (WMD: − 0.61 kg; 95% CI − 1.70 to 0.47; p = 0.87) or percent weight loss (WMD: − 0.38%, − 1.16 to 0.40; p = 0.34) when compared to the continuous approach. A slight reduction in fasting insulin concentrations was evident with IER regimens (WMD = − 0.89 µU/mL; − 1.56 to − 0.22; p = 0.009), but the clinical relevance of this result is uncertain. No between-arms differences in the other variables were found.

Conclusions

Both intermittent and continuous energy restriction achieved a comparable effect in promoting weight-loss and metabolic improvements. Long-term trials are needed to draw definitive conclusions.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1748-4) contains supplementary material, which is available to authorized users.

Rationale for novel intermittent dieting strategies to attenuate adaptive responses to energy restriction

Eating patterns involving intermittent energy restriction (IER) include 'intermittent fasting' where energy intake is severely restricted for several 'fasting' days per week, with 'refeeding' days (involving greater energy intake than during fasting days) at other times. Intermittent fasting does not improve weight loss compared to continuous energy restriction (CER), where energy intake is restricted every day. We hypothesize that weight loss from IER could be improved if refeeding phases involved restoration of energy balance (i.e. not ongoing energy restriction, as during intermittent fasting). There is some evidence in adults with overweight or obesity showing that maintenance of a lower weight may attenuate (completely or partially) some of the adaptive responses to energy restriction that oppose ongoing weight loss. Other studies show some adaptive responses persist unabated for years after weight loss. Only five randomized controlled trials in adults with overweight or obesity have compared CER with IER interventions that achieved energy balance (or absence of energy restriction) during refeeding phases. Two reported greater weight loss than CER, whereas three reported similar weight loss between interventions. While inconclusive, it is possible that achieving energy balance (i.e. avoiding energy restriction or energy excess) during refeeding phases may be important in realizing the potential of IER.

Quantifying the imprecision of energy intake of humans to compensate for imposed energetic errors: A challenge to the physiological control of human food intake

To assess the precision of the biological control of energy intake we performed a systematic review of studies that measured acute changes in human food intake in response to energetic errors. The imposed errors were grouped into the following categories of studies: alternate day fasting, changes in diet composition, exercise, meal skipping, overfeeding, energy substitutes, underfeeding and changes in portion size. Seven hundred thirty-nine studies published between 1980 and 2017 were identified from which the data from 592 groups from 200 studies were extracted and subjected to analysis consisting of a total of 13,203 participants. For each category of imposing an energetic error, an Energetic Error was calculated as (Observed Mean Energy Intake - Expected Mean Energy Intake)/Expected Mean Energy Intake. In no category of studies was the Energetic Error equal to zero. In studies where participants were expected to increase energy intake, the increase was not sufficient to overcome the deficit. Similarly, in studies where a reduction in energy intake was expected, the reduction was insufficient to restore energy balance to zero. The average energetic error resulting from imposed energetic challenges is about twenty-four percent, a value sufficiently large to account for the increase in body weight observed in the U.S. population over the past 50 years.

Intermittent administration of a fasting-mimicking diet intervenes in diabetes progression, restores β cells and reconstructs gut microbiota in mice

Fasting and especially intermittent fasting have been shown to be an effective intervention in many diseases, such as obesity and diabetes. The fasting-mimicking diet (FMD) has recently been found to ameliorate metabolic disorders. To investigate the effect of a new type of low-protein low-carbohydrate FMD on diabetes, we tested an FMD in db/db mice, a genetic model of type 2 diabetes. The diet was administered every other week for a total of 8 weeks. The intermittent FMD normalized blood glucose levels in db/db mice, with significant improvements in insulin sensitivity and β cell function. The FMD also reduced hepatic steatosis in the mice. Deterioration of pancreatic islets and the loss of β cells in the diabetic mice were prevented by the FMD. The expression of β cell progenitor marker Ngn3 was increased by the FMD. In addition, the FMD led to the reconstruction of gut microbiota. Intermittent application of the FMD increased the genera of Parabacteroides and Blautia while reducing Prevotellaceae, Alistipes and Ruminococcaceae. The changes in these bacteria were also correlated with the fasting blood glucose levels of the mice. Furthermore, intermittent FMD was able to reduce fasting blood glucose level and increase β cells in STZ-induced type 1 diabetic mouse model. In conclusion, our study provides evidence that the intermittent application of an FMD is able to effectively intervene in the progression of diabetes in mice.

A time to fast

Nutrient composition and caloric intake have traditionally been used to devise optimized diets for various phases of life. Adjustment of meal size and frequency have emerged as powerful tools to ameliorate and postpone the onset of disease and delay aging, whereas periods of fasting, with or without reduced energy intake, can have profound health benefits. The underlying physiological processes involve periodic shifts of metabolic fuel sources, promotion of repair mechanisms, and the optimization of energy utilization for cellular and organismal health. Future research endeavors should be directed to the integration of a balanced nutritious diet with controlled meal size and patterns and periods of fasting to develop better strategies to prevent, postpone, and treat the socioeconomical burden of chronic diseases associated with aging.

Endogenous secretory RAGE increases with improvements in body composition and is associated with markers of adipocyte health

BACKGROUND AND AIMS

The receptor for advanced glycation end products (RAGE) is implicated in obesogenesis. Conversely, soluble RAGE (sRAGE) competitively inhibits RAGE. Our aim was to determine the effects of weight-loss via alternate day fasting (ADF) on sRAGE isoforms and evaluate potential relationships with body composition.

METHODS AND RESULTS

42 obese participants were randomized to control (CON) or ADF. For 24 weeks, the ADF group consumed 25% or 125% of their caloric requirements on alternating days while the CON group did not change their diet. Body fat was measured via DXA, visceral fat (VAT) via MRI and subcutaneous fat (SAT) was derived by subtracting VAT from total fat. sRAGE isoforms were measured via ELISAs. After 24 weeks, ADF -6.8 (-9.5, -3.5)kg (Median, IQR) lost more weight than CON -0.3 (-1.9, 1.0)kg (p < 0.05). The change in endogenous secretory RAGE (esRAGE) was different between ADF 15 (-30, 78)pg/mL and CON -21 (-72, 16)pg/mL after 24 weeks (p < 0.05). To examine the effect of changes in body composition, the cohort was stratified by median weight-, fat-, SAT-, and VAT-loss. The changes in all sRAGE isoforms were different between those above and below median weight-loss (p < 0.05) with sRAGE isoforms tending to decrease in individuals below the median. Changes in total sRAGE and esRAGE were different between individuals above compared to below median fat- and SAT-loss (p < 0.05). Those above median fat-loss increased esRAGE by 29 (-5, 66)pg/mL (p < 0.05).

CONCLUSION

Improvements in body composition are related to increased sRAGE isoforms, implicating sRAGE as a potential target for the treatment of obesity.

CLINICAL TRIAL REGISTRATION

NCT00960505.

Effects of intermittent and continuous calorie restriction on body weight and metabolism over 50 wk: a randomized controlled trial

Background

Although preliminary evidence suggests that intermittent calorie restriction (ICR) exerts stronger effects on metabolic parameters, which may link obesity and major chronic diseases, compared with continuous calorie restriction (CCR), there is a lack of well-powered intervention studies.

Objective

We conducted a randomized controlled trial to test whether ICR, operationalized as the "5:2 diet," has stronger effects on adipose tissue gene expression, anthropometric and body composition measures, and circulating metabolic biomarkers than CCR and a control regimen.

Design

One hundred and fifty overweight and obese nonsmokers [body mass index (kg/m2) ≥25 to <40, 50% women], aged 35-65 y, were randomly assigned to an ICR group (5 d without energy restriction and 2 d with 75% energy deficit, net weekly energy deficit ∼20%), a CCR group (daily energy deficit ∼20%), or a control group (no advice to restrict energy) and participated in a 12-wk intervention phase, a 12-wk maintenance phase, and a 26-wk follow-up phase.

Results

Loge relative weight change over the intervention phase was -7.1% ± 0.7% (mean ± SEM) with ICR, -5.2% ± 0.6% with CCR, and -3.3% ± 0.6% with the control regimen (Poverall < 0.001, PICR vs. CCR = 0.053). Despite slightly greater weight loss with ICR than with CCR, there were no significant differences between the groups in the expression of 82 preselected genes in adipose tissue implicated in pathways linking obesity to chronic diseases. At the final follow-up assessment (week 50), weight loss was -5.2% ± 1.2% with ICR, -4.9% ± 1.1% with CCR, and -1.7% ± 0.8% with the control regimen (Poverall = 0.01, PICR vs. CCR = 0.89). These effects were paralleled by proportional changes in visceral and subcutaneous adipose tissue volumes. There were no significant differences between ICR and CCR regarding various circulating metabolic biomarkers.

Conclusion

Our results on the effects of the "5:2 diet" indicate that ICR may be equivalent but not superior to CCR for weight reduction and prevention of metabolic diseases. This trial was registered at clinicaltrials.gov as NCT02449148.

Continuous versus intermittent moderate energy restriction for increased fat mass loss and fat free mass retention in adult athletes: protocol for a randomised controlled trial-the ICECAP trial (Intermittent versus Continuous Energy restriction Compared in an Athlete Population)

Introduction

Reducing fat mass (FM) while retaining fat free mass (FFM) is a common goal of athletes. Evidence suggests that some-but not all-forms of intermittent energy restriction (IER) may be superior to the conventional method of continuous energy restriction (CER) for people with excess body fat that are sedentary, by reducing some of the adaptive responses to ER. However, it is yet to be established whether this dietary approach is effective for athletes.

Methods and analysis

A single-blind, parallel group, randomised controlled trial with a 1:1 allocation ratio is proposed. Sixty healthy athletes aged ≥18 years will be recruited from local sporting facilities and randomised to an intervention of either moderate CER (mCER) or moderate IER (mIER). Both interventions will consist of 12 weeks of moderate ER, plus 3 weeks in energy balance (EB). The mCER intervention will entail 12 weeks of continuous moderate ER, followed by 3 weeks in EB. The mIER intervention will entail 12 weeks of moderate ER, administered as 4×3 week blocks of moderate ER, interspersed with 3×1 week blocks of EB. The co-primary outcomes are changes in FM and FFM after 12 weeks of moderate ER. Secondary outcomes will be changes in FM and FFM at 15 weeks after intervention commencement, as well as muscle performance, physical activity, sleep quality, changes in resting energy expenditure, subjective drive to eat, circulating concentrations of appetite-regulating hormones, mood states and diet acceptability.

Trial registration

ACTRN12618000638235p.

Effects of alternate day calorie restriction and exercise on cardio-metabolic risk factors in overweight and obese adults: an exploratory randomized controlled study

BACKGROUND

It has been recognized that alternate day calorie restriction (ADCR) or exercise has positive effects on cardio-metabolic risk factors. It is unclear whether the combined effect of ADCR and exercise (aerobic + resistance training) influences risk. We investigated effects of an 8-week ADCR and exercise program (aerobic + resistance training) on cardio-metabolic risk factors in overweight and obese adults.

METHODS

This study randomized 45 overweight or obese but healthy adults (F = 26, M = 19; aged about 32 to 40 years) into 4 groups: ADCR (n = 13), exercise (n = 10), exercise plus ADCR (n = 12), and control (n = 10) for 8 weeks. Body composition, blood lipids profile, and insulin resistance were measured. The intention to treat (ITT) method was used to analyze all participants that were randomized.

RESULTS

A total of 35 participants completed the trial (78%). Body weight, body mass index, waist circumference, fat mass and percent body fat were reduced in the exercise plus ADCR group (- 3.3 ± 2.4 kg, p < 0.01; - 1.3 ± 1.0 kg/m2, p < 0.01; - 4.1 ± 3.9 cm, p < 0.01; - 2.7 ± 2.0 kg, p < 0.01; - 2. 5 ± 2.2%, p < 0.01). Insulin, glucose, homeostasis model assessment insulin resistance and triglyceride (- 2.9 ± 4.1 μIU/ml, p < 0.05; - 10.9 ± 16.9 mg/dl, p < 0.05; - 0.9 ± 1.3, p < 0.05; - 43.8 ± 41.9 mg/dl, p < 0.01) decreased in the exercise plus ADCR group only.

CONCLUSIONS

ADCR and exercise both proved to be beneficial, but the combined intervention was most effective at inducing beneficial changes in body weight, body composition, glucose, insulin, insulin resistance and triglyceride in overweight and obese adults.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03652532 , Registered August 28, 2018, 'retrospectively registered'.