Effects and clinical potential of very-low-calorie diets (VLCDs) in type 2 diabetes

Impact of a dietitian-led very low calorie diet clinic on perioperative risk for patients with obesity awaiting elective, non-bariatric surgery: A retrospective cohort study

BACKGROUND

Despite a lack of evidence that intentional weight loss reduces the risk of postoperative complications, adults with obesity are commonly asked to lose weight before elective surgery. We hypothesized that patients undertaking dietitian-led preoperative, very low calorie diet treatment could reduce perioperative surgery risks, as per validated risk scoring systems. The purpose of this study was to measure the impact of a dietitian-led preoperative very low calorie diet clinic on the American Society of Anesthesiologists physical status scores and National Surgical Quality Improvement Program Surgical Risk Calculator scores for patients with obesity awaiting non-bariatric elective surgery.

METHODS

This retrospective cohort study included patients referred to the preoperative dietitian-led very low calorie diet clinic before elective surgical procedures over a 2-year-9-month period. The dietitian prescribed individualized, very low calorie diet-based treatment. Primary outcomes were changes in the American Society of Anesthesiologists and Surgical Risk Calculator scores from pretreatment until surgery.

RESULTS

A total of 141 eligible participants (48 ± 13.4 years, 76% women, body mass index 41.7 ± 6.3 kg/m2) demonstrated clinically significant weight loss (mean 7.1 ± 6.1kg, 5.2% body weight, P < .001). Median treatment duration was 13 weeks (interquartile range 6.2-19.2 weeks). Five participants (3.5%) avoided surgery due to weight loss-related improvements in their condition. American Society of Anesthesiologists scores improved for 16% (n = 22/141) of participants. Overall, the median surgical risk calculator estimated risk of 'serious' and 'any' postoperative complication reduced from 4.8% to 3.9% (P < .001) and 6% to 5.1% (P < .001), respectively. Reduction in all Surgical Risk Calculator scores occurred, including surgical site infection, re-admission, and cardiac events (P < .05).

CONCLUSION

The dietitian-led preoperative, very low calorie diet clinic improved American Society of Anesthesiologists and Surgical Risk Calculator scores for non-bariatric elective surgery patients with obesity. Randomized controlled trials comparing this approach with a control group are warranted.

The gut microbiome as possible mediator of the beneficial effects of very low calorie ketogenic diet on type 2 diabetes and obesity: a narrative review

Several studies have shown a strong correlation between the different types of diets and gut microbiota composition on glycemia and weight loss. In this direction, low-carbohydrate and ketogenic diets have gained popularity, despite studies published so far leading to controversial results on subjects with diabetes. In this narrative review, firstly, we aimed to analyze the role of very-low-calorie ketogenic diets (VLCKDs) in type 2 diabetes (T2DM) and obesity management. Secondly, in this context, we focused attention on gut microbiota as a function of VLCKD, particularly in T2DM and obesity treatment. Finally, we reported all this evidence to underline the importance of gut microbiota to exalt new nutritional strategies for "tailor-made" management, treatment, and rehabilitation in subjects with T2DM and obesity, even with diabetic complications. In conclusion, this narrative review outlined the beneficial impact of VLCKD on gut microbiota even in subjects with T2DM and obesity, and, despite inner VLCKD short-duration feature allowing no sound-enough provisions for long-term outcomes, witnessed in favor of the short-term safety of VLCKD in those patients.Level of evidence Level V: Opinions of authorities, based on descriptive studies, narrative reviews, clinical experience, or reports of expert committees.

Effect of 5:2 Fasting Diet on Liver Fat Content in Patients with Type 2 Diabetic with Nonalcoholic Fatty Liver Disease

Background: The prevalence of nonalcoholic fatty liver disease (NAFLD) is rapidly growing in China, especially in patients with type 2 diabetes mellitus (T2DM). Weight loss strategies have been shown to treat NAFLD effectively. We conducted a 24-week, prospective, randomized study in T2DM patients with NAFLD to evaluate the effects of a 5:2 fasting diet on liver fat content. Methods: Sixty-one T2DM patients with NAFLD were enrolled and randomly divided into a 5:2 fasting diet intervention group (5:2 diet group, n = 31) and 1.8 mg/day liraglutide intervention group (Lira group, n = 30). The study was performed for 24 weeks. Data of the body weight, waist circumference, plasma lipids and glucose profile, fasting plasma insulin, and liver function parameters were collected. Controlled attenuation parameter (CAP) was measured to assess the liver fat content. Superoxide dismutase (SOD) and malondialdehyde (MDA) were measured to evaluate oxidative stress status. Results: At 24 weeks after intervention, compared with those at baseline, CAP was significantly decreased in both the 5:2 diet group and Lira group, which was 7.4% and 5.5%, respectively. Body weight, plasma lipids and glucose profile, and liver function parameters improved significantly, while homeostasis model assessment-β (HOMA-β) was significantly increased in both groups (all P < 0.05). Stepwise linear regression showed that increased HOMA-β and SOD, as well as reduced body mass index (BMI), were the independent predictors of CAP decrease in the Lira group (P = 0.000, 0.000, 0.015). In contrast, reduced BMI and MDA were the independent influencing factors of CAP decrease in the 5:2 diet group (P = 0.011, 0.043). The common side effects in the 5:2 diet group were hunger (60%), weakness (10%), and constipation (0.3%). Conclusions: A 5:2 fasting diet achieved comparable effects with liraglutide on liver fat content in patients with T2DM with NAFLD by reducing BMI and oxidative stress. Both treatment strategies were safe and effective for glucose control.

Oxidative stress in the pathophysiology of type 2 diabetes and related complications: Current therapeutics strategies and future perspectives

Type 2 diabetes (T2DM) is a persistent metabolic disorder rising rapidly worldwide. It is characterized by pancreatic insulin resistance and β-cell dysfunction. Hyperglycemia induced reactive oxygen species (ROS) production and oxidative stress are correlated with the pathogenesis and progression of this metabolic disease. To counteract the harmful effects of ROS, endogenous antioxidants of the body or exogenous antioxidants neutralise it and maintain bodily homeostasis. Under hyperglycemic conditions, the imbalance between the cellular antioxidant system and ROS production results in oxidative stress, which subsequently results in the development of diabetes. These ROS are produced in the endoplasmic reticulum, phagocytic cells and peroxisomes, with the mitochondrial electron transport chain (ETC) playing a pivotal role. The exacerbated ROS production can directly cause structural and functional modifications in proteins, lipids and nucleic acids. It also modulates several intracellular signaling pathways that lead to insulin resistance and impairment of β-cell function. In addition, the hyperglycemia-induced ROS production contributes to micro- and macro-vascular diabetic complications. Various in-vivo and in-vitro studies have demonstrated the anti-oxidative effects of natural products and their derived bioactive compounds. However, there is conflicting clinical evidence on the beneficial effects of these antioxidant therapies in diabetes prevention. This review article focused on the multifaceted role of oxidative stress caused by ROS overproduction in diabetes and related complications and possible antioxidative therapeutic strategies targeting ROS in this disease.

Traditional and Medical Applications of Fasting

Fasting has been practiced for millennia, for religious, ethical, or health reasons. It is also commonplace among different species, from humans, to animals, to lower eukaryotes. Research on fasting is gaining traction based on recent studies that show its role in many adaptive cellular responses such as the reduction of oxidative damage and inflammation, increase of energy metabolism, and in boosting cellular protection. In this expert review, we recount the historical evolution of fasting and we critically analyze its current medical applications, including benefits and caveats. Based on the available data, we conclude that the manipulation of dietary intake, in the form of calorie restriction, intermittent fasting, dietary restriction with the exclusion of some nutrients, prolonged fasting, and so forth, is anthropologically engraved in human culture possibly because of its positive health effects. Indeed, many studies show that fasting ameliorates many biochemical parameters related to cardiovascular and cancer risk, and neurodegeneration. Mechanistic studies are plentiful, but largely limited to cell cultures or laboratory animals. Understandably, there are no controlled trials of any form of fasting that gauge the effects on [any cause] mortality. Physicians should be aware that misinformation is pervasive and that their patients often adopt dietary regimens that are far from being clinically validated. Moreover, doctors are often unaware of their patients’ religious or traditional fasting and of its potential health effects. Based on current evidence, no long-term fasting should be undertaken without medical supervision until future research will hopefully help shed further light on fasting and its effects on human health.

Effects of intermittent very-low calorie diet on glycemic control and cardiovascular risk factors in obese patients with type 2 diabetes mellitus: A randomized controlled trial

AIMS/INTRODUCTION

Very few studies assess the effectiveness of different protocols of intermittent very-low calorie diet (VLCD) in patients with diabetes. This study was designed to compare the effects of 2 days/week and 4 days/week of intermittent VLCD on glycemic control, diabetes remission, metabolic parameters and quality of life in patients with type 2 diabetes and obesity.

MATERIALS AND METHODS

Participants with obesity and type 2 diabetes were recruited and randomly assigned to three groups, consisting of control, 2 days/week and 4 days/week of intermittent VLCD. In the intermittent VLCD groups, participants received a 600-kcal diet per day on restricted days and ad libitum food consumption on non-restricted days. Glycemic control, rate of diabetes remission, metabolic parameters and quality of life were evaluated at baseline, weeks 2, 10 and 20.

RESULTS

A total of 40 participants were enrolled. The mean body mass index was 30.1 ± 5.9 kg/m2 , and the mean glycated hemoglobin was 7.4 ± 1.2%. At week 20, there was an improvement in glycemic control in both intermittent VLCD groups with significant decreases in glycated hemoglobin levels and insulin resistance index throughout the study periods. Diabetes remission without the need for medications was equally found in 29% of participants in both intermittent VLCD groups. Serum triglyceride, bodyweight, body mass index and fat mass were also significantly decreased in both VLCD groups. No serious adverse events were encountered.

CONCLUSION

Intermittent VLCD was highly effective in achieving optimal glycemic control. The effects of 2 days/week and 4 days/week of intermittent VLCD on diabetes remission were relatively similar.

The effects of intermittent fasting regimens in middle-age and older adults: Current state of evidence

Aging is associated with a host of biological changes that contribute to a progressive decline in cognitive and physical function, ultimately leading to a loss of independence and an increased risk of mortality. The unprecedented growth of the aging population has thus created an urgent need for interventions that can preserve older adults' capacity to live independently and to function well. To date, there is no conclusive evidence supporting the efficacy of an intervention to prevent or reverse physical disability in older persons at risk of functional decline. A growing body of evidence indicates that prolonged fasting periods and different types of intermittent fasting regimens can have positive effects on anthropometric and metabolic health parameters in middle-aged adults similar to that of calorie restriction. For this reason, there is increasing scientific interest in further exploring the biological and metabolic effects of intermittent fasting approaches, as well as the feasibility and safety of popular types of intermittent fasting regimens in older adults. Thus, the purpose of the present review is to describe the state of evidence of different types of intermittent fasting regimes, specifically time-restricted eating and 5:2 intermittent fasting, in the growing population of middle-aged and older adults. A small, but growing body of evidence indicates both time restricted eating (TRE) and 5:2 intermittent fasting approaches can produce modest weight loss; however, only the 5:2 approach produced clinically meaningful weight losses. Reductions in blood pressure were observed for both TRE and 5:2 fasting approaches, but the effects were not consistent across studies. The majority of studies to date, in middle-age and older adults, however, have been of short duration in small study samples. Future clinical trials with larger populations and longer intervention durations are required to better understand the risks versus benefits of different types of intermittent fasting regimens in middle-age and older individuals.

Efficacy of Dietary and Supplementation Interventions for Individuals with Type 2 Diabetes

The prevalence of Type 2 diabetes (T2D) is increasing, which creates a large economic burden. Diet is a critical factor in the treatment and management of T2D; however, there are a large number of dietary approaches and a general lack of consensus regarding the efficacy of each. Therefore, the purpose of this narrative review is twofold: (1) to critically evaluate the effects of various dietary strategies on diabetes management and treatment, such as Mediterranean diet, plant-based diet, low-calorie and very low-calorie diets, intermittent fasting, low-carbohydrate and very low-carbohydrate diets, and low glycemic diets and (2) to examine several purported supplements, such as protein, branched-chain amino acids, creatine, and vitamin D to improve glucose control and body composition. This review can serve as a resource for those wanting to evaluate the evidence supporting the various dietary strategies and supplements that may help manage T2D.

Very-Low-Calorie Ketogenic Diet as a Safe and Valuable Tool for Long-Term Glycemic Management in Patients with Obesity and Type 2 Diabetes

Obesity-related type 2 diabetes represents one of the most difficult challenges for the healthcare system. This retrospective study aims to determine the efficacy, safety and durability of a very-low-calorie ketogenic diet (VLCKD), compared to a standard low-calorie diet (LCD) on weight-loss, glycemic management, eating behavior and quality of life in patients with type 2 diabetes (T2DM) and obesity. Thirty patients with obesity and T2DM, aged between 35 and 75 years, who met the inclusion criteria and accepted to adhere to a VLCKD or a LCD nutritional program, were consecutively selected from our electronic database. Fifteen patients followed a structured VLCKD protocol, fifteen followed a classical LCD. At the beginning of the nutritional protocol, all patients were asked to stop any antidiabetic medications, with the exception of metformin. Data were collected at baseline and after 3 (T1) and 12 (T2) months. At T1 and T2, BMI was significantly reduced in the VLCKD group (p < 0.001), whereas it remained substantially unchanged in the LCD group. HbA1c was significantly reduced in the VLCKD group (p = 0.002), whereas a slight, although not significant, decrease was observed in the LCD group. Quality of life and eating behavior scores were improved in the VLCKD group, whereas no significant changes were reported in the LCD group, both at T1 and T2. At the end of the study, in the VLCKD group 26.6% of patients had stopped all antidiabetic medications, and 73.3% were taking only metformin, whereas 46.6% of LCD patients had to increase antidiabetic medications. The study confirms a valuable therapeutic effect of VLCKD in the long-term management of obesity and T2DM and its potential contribution to remission of the disease.

Lemon Extract Reduces Angiotensin Converting Enzyme (ACE) Expression and Activity and Increases Insulin Sensitivity and Lipolysis in Mouse Adipocytes

Obesity is associated with insulin resistance and cardiovascular complications. In this paper, we examine the possible beneficial role of lemon juice in dieting. Lemon extract (LE) has been proposed to improve serum insulin levels and decrease angiotensin converting enzyme (ACE) activity in mouse models. ACE is also a biomarker for sustained weight loss and ACE inhibitors improve insulin sensitivity in humans. Here, we show that LE impacts adipose tissue metabolism directly. In 3T3-L1 differentiated adipocyte cells, LE improved insulin sensitivity as evidenced by a 3.74 ± 0.54-fold increase in both pAKT and GLUT4 levels. LE also induced lipolysis as demonstrated by a 16.6 ± 1.2 fold-change in pHSL protein expression levels. ACE gene expression increased 12.0 ± 0.1 fold during differentiation of 3T3-L1 cells in the absence of LE, and treatment with LE decreased ACE gene expression by 80.1 ± 0.5% and protein expression by 55 ± 0.37%. We conclude that LE's reduction of ACE expression causes increased insulin sensitivity and breakdown of lipids in adipocytes.

Adjuvant Therapies in Diabetic Retinopathy as an Early Approach to Delay Its Progression: The Importance of Oxidative Stress and Inflammation

Diabetes mellitus (DM) is a progressive disease induced by a sustained state of chronic hyperglycemia that can lead to several complications targeting highly metabolic cells. Diabetic retinopathy (DR) is a multifactorial microvascular complication of DM, with high prevalence, which can ultimately lead to visual impairment. The genesis of DR involves a complex variety of pathways such as oxidative stress, inflammation, apoptosis, neurodegeneration, angiogenesis, lipid peroxidation, and endoplasmic reticulum (ER) stress, each possessing potential therapeutic biomarkers. A specific treatment has yet to be developed for early stages of DR since no management is given other than glycemic control until the proliferative stage develops, offering a poor visual prognosis to the patient. In this narrative review article, we evaluate different dietary regimens, such as the Mediterranean diet, Dietary Pattern to Stop Hypertension (DASH) and their functional foods, and low-calorie diets (LCDs). Nutraceuticals have also been assessed in DR on account of their antioxidant, anti-inflammatory, and antiangiogenic properties, which may have an important impact on the physiopathology of DR. These nutraceuticals have shown to lower reactive oxygen species (ROS), important inflammatory factors, cytokines, and endothelial damage biomarkers either as monotherapies or combined therapies or concomitantly with established diabetes management or nonconventional adjuvant drugs like topical nonsteroidal anti-inflammatory drugs (NSAIDs).

Obesity in older adults: Effect of degree of weight loss on cardiovascular markers and medications

Obesity worsens the age-related tendency towards cardiovascular disease and diabetes. Older adults are vulnerable to medication adverse effects. Intentional weight loss in older adults with obesity has been shown to improve cardiovascular and glycaemic markers. The effect of rapid weight loss induced by very-low-calorie diets (VLCDs) on these markers has not been evaluated in this group. In this 12-week study, participants were randomized to one of healthy eating, hypocaloric diet or VLCD, all combined with three times weekly exercise (Ex/HE, Ex/Diet, Ex/VLCD, respectively). The effects of these interventions on weight, blood pressure, lipids, glucose and HbA_1c , inflammatory markers and cardiovascular and diabetes medication changes were measured. Weight loss was 3.7%, 5.1% and 11.1% in Ex/HE, Ex/Diet and Ex/VLCD, respectively. There were significant improvements in HbA_1c in all groups, but by the greatest degree in Ex/VLCD (0.18 ± 0.07%, 0.18 ± 0.06% and 0.59 ± 0.13%, respectively). Similar patterns were seen in total cholesterol (0.13 ± 0.15, 0.21 ± 0.11 and 0.53 ± 0.13 mmol/L, respectively, P = .047), triglycerides (0.35 ± 0.13, 0.20 ± 0.10 and 0.51 ± 0.09 mmol/L, respectively, P = .011) and systolic blood pressure (9 ± 2, 2 ± 3 and 14 ± 3 mmHg respectively, P = .025). There were no between-group differences in fasting glucose, high-density lipoprotein (HDL) cholesterol, LDL-C and inflammatory markers. Reductions in anti-hypertensive or diabetes medication were made in 4/29, 7/36 and 16/37 participants in Ex/HE, Ex/Diet and Ex/VLCD, respectively (P = .017). Significant weight loss achieved with a VLCD gave rise to improvements in multiple cardiovascular risk markers, despite reduction in medication. Weight loss is an under-utilized method of cardiovascular risk management in this group.

Flash glucose monitoring for the safe use of a 2-day intermittent energy restriction in patients with type 2 diabetes at risk of hypoglycaemia: An exploratory study

AIMS

Two medication change protocols were tested, both based on haemoglobin A1c (HbA1c), with one protocol also accounting for hypoglycaemic events. The aim was to compare the two protocols during intermittent energy restriction (5:2 diet).

METHODS

Forty-two adults with type 2 diabetes (HbA1c ≥ 7% [53 mmol/mol], BMI of ≥27 kg/m²) treated with sulphonylureas and/or insulin were recruited and randomised 1:1 to fixed or adjusted medication protocols. Participants experiencing hypoglycaemia during a 2-week usual diet period then followed the 5:2 diet for 2 weeks (2 non-consecutive very-low-calorie days [500-600 kcal] and 5 habitual eating days/week), following the allocated medication protocol. The primary outcome was to determine if the adjusted protocol was superior to the fixed protocol at reducing hypoglycaemic events during the 5:2 diet. Flash glucose monitoring was used throughout to detect hypoglycaemia.

RESULTS

There was a significant difference in change in the number of hypoglycaemic events between fixed and adjusted protocols (-1.0 vs. -3.5; P = 0.04). Over 60% of participants on the adjusted protocol had no hypoglycaemic events.

CONCLUSIONS

This pilot study demonstrates the importance of assessing the risk of hypoglycaemia before starting a 5:2 diet and that the adjusted medication protocol is likely the best option for patients at risk.

CLINICAL TRIAL REGISTRY

This study has been registered with the Australia New Zealand Clinical Trial Registry (ANZCTR) www.anzctr.org.au and given the registration number ACTRN12617000512325.

Immediate and long-term effects of a very-low-calorie diet on diabetes remission and glycemic control in obese Thai patients with type 2 diabetes mellitus

AIM

A very-low-calorie diet (VLCD) can reverse the underlying defects of type 2 diabetes mellitus (DM) in obese subjects. We determined the efficacy, safety, and durability of VLCD in Thai patients with DM and obesity.

METHODS

Twenty Thai patients with DM and obesity were enrolled. After a 2-week trial, VLCD (600 kcal/day) was continued for 8 weeks, followed by a 4-week transition period. Data on diabetes remission (fasting plasma glucose level <126 mg/dl and HbA1c <6.5% without the use of glucose-lowering medications), glycemic control, metabolic parameters, and quality of life (QOL) were collected along with indices of insulin resistance (IR) and beta cell function. Glycemic control 12 months after discontinuation of VLCD was also examined.

RESULTS

Among 19 patients (age 48 ± 2 years, BMI 27.7 kg/m2) who completed the study, rapid improvement in glycemic control was observed in the first 2 weeks of VLCD. At both 8 and 12 weeks, diabetes remission was achieved in 79%. Significant weight loss was accompanied by a significant reduction in IR and an increase in beta cell function, starting at 4 weeks of VLCD. QOL also significantly increased. At 12 months after VLCD, however, DM remission was achieved in approximately 30%.

CONCLUSION

Very-low-calorie diet was effective and safe in inducing short-term diabetes remission in Thai subjects by ameliorating beta cell function and IR. Optimal long-term glycemic control was potentially durable as one-third of subjects remained without diabetes medication 12 months after VLCD.

Effect of Intermittent Compared With Continuous Energy Restricted Diet on Glycemic Control in Patients With Type 2 Diabetes: A Randomized Noninferiority Trial

IMPORTANCE

Intermittent energy restriction is an alternative weight loss method that is becoming popular; however, to date, there are no long-term clinical trials of intermittent energy restriction in patients with type 2 diabetes.

OBJECTIVE

To compare the effects of intermittent energy restriction (2 days per week) with those of continuous energy restriction on glycemic control and weight loss in patients with type 2 diabetes during a 12-month period.

DESIGN, SETTING, AND PARTICIPANTS

Adult participants (N = 137) with type 2 diabetes were randomized 1:1 to parallel diet groups (intermittent energy restriction [n = 70] or continuous energy restriction [n = 67]) between April 7, 2015, and September 7, 2017, at the University of South Australia. Medications likely to cause hypoglycemia were reduced at baseline according to the medication management protocol.

INTERVENTIONS

An intermittent energy restriction diet (500-600 kcal/d) followed for 2 nonconsecutive days per week (participants followed their usual diet for the other 5 days) or a continuous energy restriction diet (1200-1500 kcal/d) followed for 7 days per week for 12 months.

MAIN OUTCOMES AND MEASURES

The primary outcome was change in hemoglobin A1c (HbA1c) level, with equivalence prespecified by a 90% CI margin of ±0.5%. The secondary outcome was weight loss with equivalence set at ±2.5 kg (±1.75 kg for fat mass loss and ±0.75 kg for fat-free mass loss). All other outcomes were tested for superiority.

RESULTS

Of the 137 randomized participants (77 women and 60 men; mean [SD] age, 61.0 [9.1] years; mean [SD] body mass index, 36.0 [5.8] [calculated as weight in kilograms divided by height in meters squared]; and mean [SD] HbA1c level, 7.3% [1.3%]), 97 completed the trial. Intention-to-treat analysis showed similar reductions in mean (SEM) HbA1c level between the continuous and intermittent energy restriction groups (-0.5% [0.2%] vs -0.3% [0.1%]; P = .65), with a between-group difference of 0.2% (90% CI, -0.2% to 0.5%) meeting the criteria for equivalence. Mean (SEM) weight change was similar between the continuous and intermittent energy restriction groups (-5.0 [0.8] kg vs -6.8 [0.8] kg; P = .25), but the between-group difference did not meet the criteria for equivalence (-1.8 kg; 90% CI, -3.7 to 0.07 kg), nor did the between-group difference in fat mass (-1.3 kg; 90% CI, -2.8 to 0.2 kg) or fat-free mass (-0.5 kg; 90% CI, -1.4 to 0.4 kg). There were no significant differences between groups in final step count, fasting glucose levels, lipid levels, or total medication effect score at 12 months. Effects did not differ using completers analysis. Hypoglycemic or hyperglycemic events in the first 2 weeks of treatment were similar between the continuous and intermittent energy restriction groups (mean number [SEM] of events, 3.2 [0.7] vs 4.9 [1.4]; P = .28), affecting 35% of participants (16 of 46) using sulfonylureas and/or insulin.

CONCLUSIONS AND RELEVANCE

Intermittent energy restriction is an effective alternative diet strategy for the reduction of HbA1c and is comparable with continuous energy restriction in patients with type 2 diabetes.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12615000383561.

Intermittent energy restriction in type 2 diabetes: A short discussion of medication management

AIM

To discuss type 2 diabetes mellitus (T2DM) medication changes required during the popular 5:2 intermittent energy restriction (IER) diet.

METHODS

A search was conducted in MEDLINE, EMBASE, AMED, CINAHL and Cochrane library for original research articles investigating the use of very low calorie diets (VLCD) in people with T2DM. The search terms used included “VLCD” or “very low energy diet” or “very low energy restriction” or “IER” or “intermittent fasting” or “calorie restriction” or “diabetes mellitus type 2” and “type 2 diabetes”. Reference lists of selected articles were also screened for relevant publications. Only research articles written in English, which also included an explanation of medication changes were included. A recent pilot trial using the 5:2 IER method, conducted by our research group, will also be summarized.

RESULTS

A total of 8 studies were found that investigated the use of VLCD in T2DM and discussed medication management. Overall these studies indicate that the use of a VLCD for people with T2DM usually require the cessation of medication to prevent hypoglycemia. Therefore, the 5:2 IER method will also require medication changes, but as seen in our pilot trial, may not require total cessation of medication, rather a cessation on the 2 IER days only.

CONCLUSION

Guidelines outlined here can be used in the initial stages of a 2-d IER diet, but extensive blood glucose monitoring is still required to make the necessary individual reductions to medications in response to weight loss.

Fast versus slow weight loss: development process and rationale behind the dietary interventions for the TEMPO Diet Trial

OBJECTIVE AND METHODS

Finding effective solutions to curb the obesity epidemic is a great global public health challenge. The need for long-term follow-up necessitates weight loss trials conducted in real-world settings, outside the confines of tightly controlled laboratory or clinic conditions. Given the complexity of eating behaviour and the food supply, this makes the process of designing a practical dietary intervention that stands up to scientific rigor difficult. Detailed information about the dietary intervention itself, as well as the process of developing the final intervention and its underlying rationale, is rarely reported in scientific weight management publications but is valuable and essential for translating research into practice. Thus, this paper describes the design process and underlying rationale behind the dietary interventions in an exemplar weight loss trial - the TEMPO Diet Trial (Type of Energy Manipulation for Promoting optimal metabolic health and body composition in Obesity). This trial assesses the long-term effects of fast versus slow weight loss on adiposity, fat free mass, muscle strength and bone density in women with obesity (body mass index 30-40 kg m-2) that are 45-65 years of age, postmenopausal and sedentary.

RESULTS AND CONCLUSIONS

This paper is intended as a resource for researchers and/or clinicians to illustrate how theoretical values based on a hypothesis can be translated into a dietary weight loss intervention to be used in free-living women of varying sizes.

The Protein-Sparing Modified Fast Diet: An Effective and Safe Approach to Induce Rapid Weight Loss in Severely Obese Adolescents

Objectives: The protein-sparing modified fast (PSMF) is a rigorous way of rapidly losing a large amount of weight. Although adult studies have shown the PSMF to be effective, data in adolescents are lacking. The aim of this study was to determine the efficacy and safety of the PSMF in severely obese adolescents. Methods: 12 subjects who were evaluated in the Obesity Management Program at the Cleveland Clinic from 2011 to 2014 were included. The subjects were initiated on the PSMF after failing other conventional methods of weight loss. Once the goal weight was achieved, subjects were transitioned to the refeeding phase for weight maintenance. Results: Follow-up was scheduled at 3-month (11 patients) and 6-month (6 patients) intervals. At the 6-month follow-up visit, the average weight loss was 11.19 kg (95% confidence interval = -5.4, -27.8, P = .028), with average of 9.8% from baseline. Fifty percent of subjects had >5% weight loss and 20% had >10% weight loss. Four patients were lost to the follow-up (40%). An improvement was noted in total cholesterol and high-density lipoprotein. Due to a small sample size these results were not statistically significant. Side effects reported by subjects were mild dehydration due to nausea (2 patients), decreased energy (1 patient), and transient labile mood (1 patient). No life-threatening side effects were reported. Conclusion: Our results show that the PSMF diet can be used as an effective and safe method in the outpatient setting for rapid weight loss in adolescents with severe obesity.

Bariatric surgery in class I obesity : a Position Statement from the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO)

Class I obesity conveys an increased risk of comorbidities, impairs physical and mental health-related quality of life, and it is associated to an increased psychosocial burden, particularly in women. The need for effective and safe therapies for class I obesity is great and not yet met by nonsurgical approaches. Eligibility to bariatric surgery has been largely based on body mass index (BMI) cut points and limited to patients with more severe obesity levels. However, obese patients belonging to the same BMI class may have very different levels of health, risk, and impact of obesity on quality of life. Individual patients in class I obesity may have a comorbidity burden similar to, or greater than, patients with more severe obesity. Therefore, the denial of bariatric surgery to a patient with class I obesity suffering from a significant obesity-related health burden and not achieving weight control with nonsurgical therapy simply on the basis of the BMI level does not appear to be clinically justified. A clinical decision should be based on a more comprehensive evaluation of the patient's current global health and on a more reliable prediction of future morbidity and mortality. After a careful review of available data about safety and efficacy of bariatric surgery in patients with class I obesity, this panel reached a consensus on ten clinical recommendations.

Lemon detox diet reduced body fat, insulin resistance, and serum hs-CRP level without hematological changes in overweight Korean women

The lemon detox program is a very low-calorie diet which consists of a mixture of organic maple and palm syrups, and lemon juice for abstinence period of 7 days. We hypothesized that the lemon detox program would reduce body weight, body fat mass, thus lowering insulin resistance and known risk factors of cardiovascular disease. We investigated anthropometric indices, insulin sensitivity, levels of serum adipokines, and inflammatory markers in overweight Korean women before and after clinical intervention trial. Eighty-four premenopausal women were randomly divided into 3 groups: a control group without diet restriction (Normal-C), a pair-fed placebo diet group (Positive-C), and a lemon detox diet group (Lemon-D). The intervention period was 11 days total: 7 days with the lemon detox juice or the placebo juice, and then 4 days with transitioning food. Changes in body weight, body mass index, percentage body fat, and waist-hip ratio were significantly greater in the Lemon-D and Positive-C groups compared to the Normal-C group. Serum insulin level, homeostasis model assessment insulin resistance scores, leptin, and adiponectin levels decreased in the Lemon-D and Positive-C groups. Serum high-sensitive C-reactive protein (hs-CRP) levels were also reduced only in the Lemon-D group. Hemoglobin and hematocrit levels remained stable in the Lemon-D group while they decreased in the Positive-C and Normal-C groups. Therefore, we suppose that the lemon detox program reduces body fat and insulin resistance through caloric restriction and might have a potential beneficial effect on risk factors for cardiovascular disease related to circulating hs-CRP reduction without hematological changes.

Does weight loss in overweight or obese women improve fertility treatment outcomes? A systematic review

This systematic review assessed the effect of weight loss in overweight and/or obese women undergoing assisted reproductive technology (ART) on their subsequent pregnancy outcome. Weight losses achieved by diet and lifestyle changes, very-low-energy diets, non-surgical medical interventions and bariatric surgery translated into significantly increased pregnancy rates and/or live birth in overweight and/or obese women undergoing ART in 8 of the 11 studies reviewed. In addition, regularization of the menstrual pattern, a decrease in cancellation rates, an increase in the number of embryos available for transfer, a reduction in the number of ART cycles required to achieve pregnancy and a decrease in miscarriage rates were reported. There were also a number of natural conceptions in five of the six studies that reported this outcome. Non-surgical medical weight loss procedures and bariatric surgery induced the greatest weight losses, but their use, as well as that of very-low-energy diets, for weight loss prior to ART requires careful consideration. While the overall quality of the studies included in this review was poor, these results support the clinical recommendation of advising overweight and/or obese women to lose weight prior to ART. Prospective randomized controlled trials are required to establish efficacious evidence-based guidelines for weight loss interventions in overweight and/or obese women prior to ART treatment.

The Prevention Of WEight Regain in diabetes type 2 (POWER) study: the effectiveness of adding a combined psychological intervention to a very low calorie diet, design and pilot data of a randomized controlled trial

Background

Obesity is of major pathogenetic importance to type 2 diabetes, it contributes to poor glycemic control and increases the risk of cardiovascular disease. Over 80% of patients with diabetes type 2 are overweight. To achieve a more favourable risk profile, changes in diet and lifestyle are needed. However, current treatment programs for obese DM type 2 patients are not effective in the long term. In this RCT, we compare the effectiveness of a Combined Psychological Intervention (CPI) and usual care in maintaining the favourable effects on weight and risk profile during 2 years of follow-up after a Very Low Calorie Diet (VLCD).

Methods and design

In a randomised parallel group intervention study, 140 patients with type 2 diabetes and overweight (BMI>27 kg/m2) will be recruited from the outpatient department of the Erasmus Medical Centre.

After obtaining ≥5% of weight loss with a VLCD, participants will be randomly assigned to CPI or usual care for 10 weeks. CPI consists of cognitive behaviour therapy, problem solving therapy and proactive coping.

Primary outcome measure is weight change (kg).

Other outcome measures are Body Mass Index (BMI = weight (kg)/length (m)2), waist circumference (cm), systolic blood pressure (mmHg), HbA1c (mmol/mol), lipid levels (LDL, HDL, TG (mmol/l) and chol/HDL-ratio), antidiabetic agents and doses, cardiovascular risk profile (UKPDS), lifestyle and quality of life (EuroQol EQ-5D). Psychosocial parameters are also studied, as secondary outcomes as well as determinants for weight loss.

When successful, we want to conduct an analysis of the cost effectiveness of the intervention as compared to usual care.

Discussion

We expect that a CPI after a VLCD will be effective in maintaining weight loss and improving cardiovascular risk and glycaemic control, while being cost-effective and improving quality of life in patients with type 2 diabetes.

Clinical trials registration

trialregister.nl NTR2264

Protective effects of modified linggui zhugan decoction combined with short-term very low calorie diets on cardiovascular risk factors in obese patients with impaired glucose tolerance

OBJECTIVE

To observe the protective effects of modified Linggui Zhugan decoction combined with short-term very low calorie diets (VLCDs) on cardiovascular risk factors in obese patients with impaired glucose tolerance (IGT).

METHODS

Eighty-five obese patients with IGT of spleen hypofunction and dampness accumulation type were randomly divided into treated group (n=45)and control group (n=40). The treated group was given Linggui Zhugan decoction combined short-term VLCDs. The control group was given basic weight-reduction treatment. The total course was 6 months. Changes of fasting plasma glucose (FPG), 2-hour postprandial blood glucose (2hPG), glycosylated hemoglobin (HbA1c), fasting insulin (FINS), lipid metabolism, blood pressure, body mass index (BMI) and waist circumference (WC) were observed, and the outcomes were reviewed after the treatment.

RESULTS

Compared with the control group, the levels of FPG, 2 hPG, HbA1c, FINS, HOMA-IR decreased significantly (P < 0.05), and the indexes of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), systolic blood pressure (SBP), diastolic blood pressure (DBP), BMI and WC were improved significantly (P < 0.05) in the treated group. The transformation rate of normal glucose tolerance (NGT) was higher in treatment group than control group (P < 0.01). No severe adverse reaction was found in the therapeutic course.

CONCLUSION

The modified Linggui Zhugan decoction combined with short-term VLCDs has good protective effects on cardiovascular risk factors as a treatment intervention for IGT with obesity, as it could improve glycometabolism, significantly decrease the levels of blood pressure, blood lipids, BMI, WC and effectively cut-off and reverse the development of diabetes mellitus.

Less fat reduction per unit weight loss in type 2 diabetic compared with nondiabetic obese individuals completing a very-low-calorie diet program

The objective was to compare weight loss and change in body composition in obese subjects with and without type 2 diabetes mellitus during a very-low-calorie diet (VLCD) program. Seventy weight-matched subjects with diabetes or normal fasting glucose (controls) participated in a 24-week VLCD study. Primary end points were changes in anthropometry, body composition, and fasting plasma insulin and β-hydroxybutyrate concentrations. Fifty-one subjects (24 with diabetes) completed the study. No difference in weight loss between the 2 groups at 24 weeks was found by intention-to-treat analysis. Both groups completing the study per protocol had near-identical weight change during the program, with similar weight loss at 24 weeks (diabetes: 8.5 ± 1.3 kg vs control: 9.4 ± 1.2 kg, P = .64). Change in fat mass index correlated with change in body mass index (BMI) in both groups (diabetes: r = 0.878, control: r = 0.920, both P < .001); but change in fat mass index per unit change in BMI was less in the diabetic group compared with controls (0.574 vs 0.905 decrease, P = .003), which persisted after adjusting for age, sex, and baseline BMI (P = .008). Insulin concentrations remained higher and peak β-hydroxybutyrate concentrations were lower in the diabetic compared with the control group. While following a 24-week VLCD program, obese subjects with and without diabetes achieved comparable weight loss; but the decrease in adiposity per unit weight loss was attenuated in diabetic subjects. Hyperinsulinemia may have inhibited lipolysis in the diabetic group; however, further investigation into other factors is needed.

Economic burden of obesity in primary total knee arthroplasty

OBJECTIVE

To compare the hospital inpatient costs between nonobese and obese patients and estimate the economic burden of obesity in primary total knee arthroplasty (TKA).

METHODS

A cost identification study was conducted in a consecutive cohort of 530 patients who underwent TKA between 2006 and 2007 at a university-affiliated tertiary referral center in Melbourne, Australia. Total hospital inpatient costs incurred at the study institution associated with the index surgery and subsequent related emergency presentations and readmissions during the episode of care were captured. Predictor variables of interest were obesity and body mass index (BMI), and the outcomes of interest were total hospital inpatient costs for the index surgery and episode of care, defined as the first 12 months following TKA. Multivariate linear regression techniques were used to examine the association between the predictors of interest and hospital costs, adjusting for clinically relevant variables.

RESULTS

Economic data were analyzed in 521 patients, of which 317 (60.8%) were obese. Obesity was associated with higher inpatient index surgery costs (+$1,226.89 [95% confidence interval (95% CI) $82.25, $2,371.52]; P = 0.036) and episode of care costs (+$1,821.36 [95% CI $244.93, $3,397.79]; P = 0.024). Each unit increase in BMI was also associated with higher inpatient index surgery costs ($128.91 [95% CI $34.53, $223.28]; P = 0.008) and total episode of care costs ($158.79 [95% CI $28.54, $289.05]; P = 0.017).

CONCLUSION

The estimated significant additional annual obesity-related expenditure reported in this study establishes a rationale to trial and evaluate interventions that target weight loss in obese patients undergoing TKA from both a quality of life and economic perspective.

Effects of the modified linggui zhugan decoction (see text) combined with short-term very low calorie diets on glycemic control in newly diagnosed type 2 diabetics

OBJECTIVE

To evaluate the effects of the modified Linggui Zhugan Decoction (see text) combined with short-term very low calorie diets (VLCDs) on glycemic control in newly diagnosed type 2 diabetes mellitus (T2DM) patients.

METHODS

A total of 20 subjects with newly diagnosed T2DM were treated with the modified Linggui Zhugan Decoction (one-month administration) combined with short-term VLCDs (5 days), and 3-months follow-up. A standard 75-g oral-glucose-tolerance test (OGTT) indexes fasting plasma glucose (FPG), post-prandial 0.5 h and 2 h plasma glucose (P0.5hPG, P2hPG), glycated hemoglobin A(1c) (GHbA(1c)), body weight, body mass index (BMI), insulin function, insulin resistance index, incidence of hypoglycemia, and the liver and renal functions were evaluated before and after treatment. Correlations of BMI with insulin function and insulin resistance were also assessed.

RESULTS

After the treatment, the patients' plasma glucose decreased steadily, FPG decreased from 5.8 +/- 0.9 mmol/L at pre-treatment to 5.0 +/- 0.6 mmol/L at 3-months follow-up (P < 0.05), and P2hPG decreased from 11.7 +/- 3.8 mmol/L at pre-treatment to 6.9 +/- 0.9 mmol/L at 3-months follow-up (P < 0.01). The level of GHbA(1c) declined from (6.47 +/- 1.24)% at pre-treatment to (6.14 +/- 0.99)% at 3-months follow-up (P < 0.01). Body weight and BMI also declined significantly. Insulin resistance index was improved obviously and no event of hypoglycemia occurred. Part of the patients companied with fatty liver had a transient increase in hepatic transaminase during the treatment, but it turned to normal after the treatment.

CONCLUSIONS

The modified Linggui Zhugan Decoction combined with short-term VLCDs can be safely implemented for steady glycemic control in newly diagnosed T2DM patients.

Caloric restriction and chronic inflammatory diseases

A reduction in calorie intake [caloric restriction (CR)] appears to consistently decrease the biological rate of aging in a variety of organisms as well as protect against age-associated diseases including chronic inflammatory disorders such as cardiovascular disease and diabetes. Although the mechanisms behind this observation are not fully understood, identification of the main metabolic pathways affected by CR has generated interest in finding molecular targets that could be modulated by CR mimetics. This review describes the general concepts of CR and CR mimetics as well as discusses evidence related to their effects on inflammation and chronic inflammatory disorders. Additionally, emerging evidence related to the effects of CR on periodontal disease in non-human primates is presented. While the implementation of this type of dietary intervention appears to be challenging in our modern society where obesity is a major public health problem, CR mimetics could offer a promising alternative to control and perhaps prevent several chronic inflammatory disorders including periodontal disease.