The effect of low carbohydrate on energy metabolism

Factors Associated With Growth in Patients Treated With the Classic Ketogenic Diet for Drug-Resistant Epilepsy

BACKGROUND

Suboptimal growth and malnutrition are often cited as complications of ketogenic diet therapy in patients with drug-resistant epilepsy; however, there is conflicting evidence on the factors that contribute to growth.

METHODS

This is an observational, case-based study to evaluate growth in patients with drug-resistant epilepsy treated with the classic ketogenic diet for at least 12 months. Age, gender, height, weight, and body mass index (BMI) were collected at baseline and epilepsy clinic standard-of-care visits (one month, six months, and 12 months after diet initiation). Dietary intake and laboratory measures including glucose, bicarbonate, and beta-hydroxybutyrate were also collected.

RESULTS

119 patients were included. After ketogenic diet initiation, there was a significant fall in height z score from baseline to 12 months (-0.15, P = 0.001) but no other significant changes in weight, weight-for-length/BMI, or height z scores were noted between any time points within the 12 months after diet initiation. When separated by age, height z score changes were limited to those aged zero to three years. This was accompanied by a significant decrease in energy intake 12 months after treatment in this age group. When separated by diet route, weight z scores at each time point were significantly lower in the group eating by mouth than tube.

CONCLUSIONS

Our study provides further evidence that the classic ketogenic diet impacts growth. Our population demonstrated restriction in linear growth in those aged zero to three years, which correlated with declines in energy intake, and weight declines limited to patients fed by mouth.

A Modified Mediterranean Diet Improves Fasting and Postprandial Glucoregulation in Adults with Overweight and Obesity: A Pilot Study

The ideal lifestyle intervention to battle both obesity and diabetes is currently unknown. The aim of this pilot uncontrolled intervention trial was to assess the effect of a modified Mediterranean diet (MedDiet) on weight loss and glucoregulation among overweight/obese adults. Eleven men and women with overweight/obesity, aged 37 ± 12 years, participated in a free-living intervention until 10% weight loss was achieved. Participants followed an individualized MedDiet high in monounsaturated fat and protein with decreased carbohydrate and saturated fat contents. Physical activity and dietary intake were monitored with pedometers and food records, respectively. Upon weight loss achievement, anthropometric measurements, blood metabolic profiles and individual responses to oral glucose and mixed-meal tests were evaluated pre- and post-intervention. The results showed significant ameliorations in body fat, waist circumference and leptin levels (p < 0.01), with concomitant increases in adiponectin-leptin ratios (p < 0.001). Glucoregulation was significantly improved according to glucose and insulin responses, homeostatic model assessment of insulin resistance indices and postprandial insulin sensitivity indices (p < 0.05). In conclusion, the modified Mediterranean diet may induce significant improvements in body composition, adipocytokine profile and glucose metabolism in overweight/obese individuals. Notably, ameliorated glycemia and increased insulin sensitivity may be retained even at postprandial level, irrespective of the meal consumed.

Is a Ketogenic Diet Superior to a High-Fat, High-Cholesterol Diet Regarding Testicular Function and Spermatogenesis?

The study aimed to determine effects of a ketogenic diet on metabolic dysfunction, testicular antioxidant capacity, apoptosis, inflammation, and spermatogenesis in a high-fat and high-cholesterol diet-induced obese mice model. Forty-two male C57BL/6 mice were fed either a normal diet (NC group) or a high-fat and high-cholesterol (HFC) diet (HFC group) for 16 weeks, and mice from the HFC group were later randomly divided into two groups: the first were maintained on the original HFC diet, and the second were fed a medium-chain triacylglycerol (MCT)-based ketogenic diet for 8 weeks (KD group). A poor semen quality was observed in the HFC group, but this was eliminated by the ketogenic diet. Both the HFC and KD groups exhibited enhanced apoptosis protein expressions in testis tissue, including caspase 3 and cleaved PARP, and higher inflammation protein expressions, including TNF-α and NF-κB. However, the KD group exhibited a statistically-significant reduction in lipid peroxidation and an increased glutathione peroxidase level as compared with the HFC group. The HFC diet induced obesity in mice, which developed body weight gain, abnormal relative organ weights, metabolic dysfunction, and liver injury. Overall, the results showed that a ketogenic diet attenuated oxidative stress and improved the semen quality reduced by the HFC diet.

The Association Between Low Carbohydrate Diet and Resting Metabolic Rate in Overweight and Obese Women: A Cross-Sectional Study

Resting metabolic rate (RMR) accounts for most daily energy expenditure. The low carbohydrate diet (LCD) attenuates decreases in RMR. This study aims to investigate the relationship between an LCD and RMR status among overweight and obese women. We enrolled 291 overweight and obese women in this cross-sectional study. Body mass index (BMI), fat mass, fat-free mass, visceral fat, and insulin level were assessed. RMR was measured using indirect calorimetry. LCD score (LCDS) was measured using a validated semi-quantitative food frequency questionnaire. Analysis of variance, independent sample t-test, and Multinomial logistic regression tests were used. Results showed no relationship between LCDS and deviation of normal RMR (DNR) even after adjust for confounders (increased [Inc.] RMR: odds ratio [OR], 0.97; 95% confidence interval [CI], 0.92–1.01; p = 0.20; decreased [Dec.] RMR: OR, 0.97; 95% CI, 0.94–1.00; p = 0.14). Some components of LCDS had no significant association with DNR, such as carbohydrate and Dec. RMR in adjusted model (OR, 1.62; 95% CI, 0.98–1.37; p = 0.08) and monounsaturated fatty acids and Dec. RMR in adjusted model (OR, 0.48; 95% CI, 0.21–1.10, p = 0.08). However, refined grains had a significant association with Inc. RMR in crude model (OR, 0.87; 95% CI, 0.77–0.99, p = 0.04). There is no association between LCDS and RMR status.

Benefits of resistance training on body composition and glucose clearance are inhibited by long-term low carbohydrate diet in rats

Background/Objectives

Regular exercise training is effective to altering many markers of metabolic syndrome and its effects are strongly influenced by the type of consumed diet. Nowadays, resistance training (RT) has been frequently associated with low-carbohydrate high-fat diet (LCD). After long term these diets causes body weight (BW) regain with deleterious effects on body composition and metabolic risk factors. The effects of RT associated with long-term LCD on these parameters remain unexplored. We aimed to investigate the effects of RT when associated with long-term LCD on BW, feed efficiency, body composition, glucose homeostasis, liver parameters and serum biochemical parameters during BW regain period in rats.

Subjects/Methods

Male Sprague–Dawley rats were fed with LCD (LC groups) or standard diet (STD) (ST groups). After 10 weeks-diet animals were separated into sedentary (Sed-LC and Sed-ST) and resistance-trained (RT-LC and RT-ST) groups (N = 8/group). RT groups performed an 11-week climbing program on a ladder with progressive load. Dual x-ray absorptiometry, glucose tolerance tests and insulin tolerance tests were performed at weeks 10 and 20. Liver and serum were collected at week 21.

Results

RT reduced feed efficiency, BW gain, liver fat and total and LDL cholesterol, and improved body composition and glucose clearance in animals fed on STD. In those fed with LCD, RT reduced caloric intake, BW regain, liver fat and serum triglycerides levels. However, improvement in body composition was inhibited and bone mineral density and glucose clearance was further impaired in this association.

Conclusions

The LCD nullifies the beneficial effects of RT on body composition, glucose homeostasis and impairs some health parameters. Our results do not support the association of RT with LCD in a long term period.

No Modification in Blood Lipoprotein Concentration but Changes in Body Composition after 4 Weeks of Low Carbohydrate Diet (LCD) Followed by 7 Days of Carbohydrate Loading in Basketball Players

Recently, low carbohydrate diets have become very popular due to their numerous health benefits. Unfortunately, little is known about their chronic effects on the blood lipid profile and other cardiovascular disease risk factors in athletic populations. We compared the results of a four week, well-planned low carbohydrate diet (LCD) followed by seven days of carbohydrate loading (Carbo-L) on fasting lipids - triacylglycerol's (TAG), LDL-C, HDL-C, total cholesterol (TCh), glucose, insulin and HOMA-IR levels in 11 competitive basketball players. During the experiment, we also measured body mass (BM) and body composition changes: body fat (BF), % of body fat (PBF), and fat free mass (FFM). Both diet procedures significantly changed the fasting serum concentration of TAG (p < 0.05) and body fat content (kg and %) (p < 0.05), without negative changes in FFM. The Carbo-L procedure increased (p < 0.05) fasting glucose levels significantly. A LCD may be suggested for athletes who want to reduce body mass and fat content without compromising muscle mass. Several weeks on a LCD does not change the lipoprotein - LDL-C and HDL-C level significantly, while a seven-day Carb-L procedure may increase body fat content and fasting glucose concentration. Such dietary procedures are recommended for team sport athletes to reduce fat mass, lipid profile disorders and insulin resistance.

A high-fat diet is deleterious to mice under glycolysis restriction

It is debated whether carbohydrate restriction has metabolic advantage for its variable weight loss. Five-week-old male mice fed a high-fat diet and receiving a glycolytic inhibitor, 2-deoxyglucose, died within 9 days. They exhibited greater decreases in rectal temperature, appetite, and decline in body weight accompanied by increasing total cholesterol level than the other groups. This study suggests that carbohydrate is necessary for adequate physical and metabolic performance when lipid-rich diet is loaded.

Characteristics of Hanwoo cattle and health implications of consuming highly marbled Hanwoo beef

This review addresses the unique characteristics of Hanwoo cattle and potential health implications of consuming highly marbled Hanwoo beef. The Hanwoo breed has high genetic potential for accumulating intramuscular fat (IMF) and producing highly marbled beef. The high level of marbling is achieved through increasing levels of concentrated feed with an extended finishing period. In response to consumer preferences, the level of marbling of Hanwoo beef has been increasing. The IMF content can be manipulated depending on the feeding duration, finishing diet, and genotype. On the other hand, some consumers are expressing concern regarding the consumption of too much animal fat. This review discusses the potential of Hanwoo beef as a dietary source of heart-healthy fats. Highly marbled Hanwoo beef has a high proportion of monounsaturated fatty acid (MUFA) due to the presence of abundant oleic acid. Literature indicates that MUFAs are heart-healthy dietary fats because they can lower low-density lipoprotein (LDL)-cholesterol while increasing high-density lipoprotein (HDL)-cholesterol. Also, recent clinical trials have indicated that highly marbled beef does not increase LDL-cholesterol and consistently increases HDL-cholesterol. Finally, the current work emphasizes that consumption of high oleic acid Hanwoo beef might potentially reduce risk factors for cardiovascular disease, and may become accepted as a healthy well-being food.

State of the Art Reviews: Relationship Between Diet/ Physical Activity and Health

Obesity and 4 of the leading causes of death—heart disease, cancer, stroke, and type 2 diabetes mellitus—are related to lifestyle. The combination of a healthy weight, prudent diet, and daily physical activity clearly plays a role in primary, secondary, and tertiary prevention of these and other chronic diseases. Because nearly 65% of the adult population is overweight or obese, weight loss and maintenance are central to this review article. Improved lipid profiles, blood pressure, insulin sensitivity, and euglycemia are associated with weight loss or a normal body weight; thus, maintaining a healthy weight is a universal recommendation for health. The methods for improving lifestyle described in the section on obesity include assessing nutritional status and stages of change of the client, setting realistic goals, eating a diet high in fruits and vegetables with low-fat sources of dairy and protein, and achieving appropriate physical activity levels. The importance of physicians discussing weight with clients and vice versa is stressed. The common features of lifestyle-related diseases make them amenable to similar lifestyle interventions.

Altered metabolic homeostasis is associated with appetite regulation during and following 48-h of severe energy deprivation in adults

BACKGROUND

Military personnel frequently endure intermittent periods of severe energy deficit which can compromise health and performance. Physiologic factors contributing to underconsumption, and the subsequent drive to overeat, are not fully characterized. This study aimed to identify associations between appetite, metabolic homeostasis and endocrine responses during and following severe, short-term energy deprivation.

METHODS

Twenty-three young adults (17M/6F, 21±3years, BMI 25±3kg/m(2)) participated in a randomized, controlled, crossover trial. During separate 48-h periods, participants increased habitual energy expenditure by 1647±345kcal/d (mean±SD) through prescribed exercise at 40-65% VO2peak, and consumed provided isovolumetric diets designed to maintain energy balance at the elevated energy expenditure (EB; 36±93kcal/d energy deficit) or to produce a severe energy deficit (ED; 3681±716kcal/d energy deficit). Appetite, markers of metabolic homeostasis and endocrine mediators of appetite and substrate availability were periodically measured. Ad libitum energy intake was measured over 36h following both experimental periods.

RESULTS

Appetite increased during ED and was greater than during EB despite maintenance of diet volume (P=0.004). Ad libitum energy intake was 907kcal/36h [95% CI: 321, 1493kcal/36h, P=0.004] higher following ED compared to following EB. Serum beta-hydroxybutyrate, free fatty acids, branched-chain amino acids, dehydroepiandrosterone-sulfate (DHEA-S) and cortisol concentrations were higher (P<0.001 for all), whereas whole-body protein balance was more negative (P<0.001), and serum glucose, insulin, and leptin concentrations were lower (P<0.001 for all) during ED relative to during EB. Cortisol concentrations, but not any other hormone or metabolic substrate, were inversely associated with satiety during EB (R(2)=0.23, P=0.04). In contrast, serum glucose and DHEA-S concentrations were inversely associated with satiety during ED (R(2)=0.68, P<0.001). No associations between physiologic variables measured during EB and ad libitum energy intake following EB were observed. However, serum leptin and net protein balance measured during ED were inversely associated with ad libitum energy intake following ED (R(2)=0.48, P=0.01).

CONCLUSION

These findings suggest that changes in metabolic homeostasis during energy deprivation modulate appetite independent of reductions in diet volume. Following energy deprivation, physiologic signals of adipose and lean tissue loss may drive restoration of energy balance.

CLINICAL TRIALS REGISTRATION

www.clinicaltrials.gov #NCT01603550.

Do ketogenic diets really suppress appetite? A systematic review and meta-analysis

Very-low-energy diets (VLEDs) and ketogenic low-carbohydrate diets (KLCDs) are two dietary strategies that have been associated with a suppression of appetite. However, the results of clinical trials investigating the effect of ketogenic diets on appetite are inconsistent. To evaluate quantitatively the effect of ketogenic diets on subjective appetite ratings, we conducted a systematic literature search and meta-analysis of studies that assessed appetite with visual analogue scales before (in energy balance) and during (while in ketosis) adherence to VLED or KLCD. Individuals were less hungry and exhibited greater fullness/satiety while adhering to VLED, and individuals adhering to KLCD were less hungry and had a reduced desire to eat. Although these absolute changes in appetite were small, they occurred within the context of energy restriction, which is known to increase appetite in obese people. Thus, the clinical benefit of a ketogenic diet is in preventing an increase in appetite, despite weight loss, although individuals may indeed feel slightly less hungry (or more full or satisfied). Ketosis appears to provide a plausible explanation for this suppression of appetite. Future studies should investigate the minimum level of ketosis required to achieve appetite suppression during ketogenic weight loss diets, as this could enable inclusion of a greater variety of healthy carbohydrate-containing foods into the diet.

Ketogenic diets for weight loss: A review of their principles, safety and efficacy

SUMMARY

Low-carbohydrate "ketogenic" diets have increased in popularity over recent years as a means of weight loss. Published studies of these diets have been highly heterogeneous, and it remains unclear to what degree dietary carbohydrate intake must be restricted in order to induce ketosis. Despite concern that they are often relatively high in fat, ketogenic low-carbohydrate diets have been generally shown to compare favourably with low-fat diets in terms of weight loss and improvements in triglyceride and high-density lipoprotein levels. This review includes a brief overview of ketone body metabolism, and summarises the literature regarding the safety and efficacy of ketogenic diets for weight loss.:

Evaluation of effects of EarlyBird associated with FloraMax-B11 on Salmonella Enteritidis, intestinal morphology, and performance of broiler chickens

A posthatch fasting period of 24 to 72 h is a common and inevitable practice in commercial poultry production. This delay in start of feed intake has been reported to negatively affect yolk utilization, gastrointestinal development, slaughter weight, breast meat yield, performance, and to also depress immunological development, making the birds more susceptible to infection from pathogens such as Salmonella. Furthermore, public concerns regarding the considerable human rates of illness reported and the emergence of antibiotic-resistant strains of Salmonella have doubled the challenge on the poultry industry to find alternative means of Salmonella control. In the present study, we evaluated the effects of a combination of early feeding with probiotic supplementation on morphological development of mucosa, control of Salmonella, and overall performance in broiler chickens. We used a blend of a commercially available perinatal supplement, EarlyBird (EB; Pacific Vet Group USA Inc., Fayetteville, AR), and a successful probiotic supplement, FloraMax-B11 (FM; Pacific Vet Group USA Inc.), to evaluate the effects on gut morphology, Salmonella intestinal colonization, and horizontal transmission, along with its effects on BW and related performance in broiler chickens under simulated commercial hatching management and shipping conditions. Morphometric analysis showed increased villus height, villus width, villus to crypt ratio, and villus surface area index in chickens treated with EB + FM groups. Significant reductions in Salmonella recovery, incidence, and horizontal transmission were also observed among the same groups, suggesting beneficial effects of early feeding and competitive exclusion by probiotic bacteria. Improved gut morphology and Salmonella exclusion was very well supported by BW data with significantly lower early BW loss and overall BW gains in birds treated with EB + FM mixture. The results of this study demonstrated that the combination of EB and FM improved gut morphology, reduced the amount of Salmonella that could be recovered, as well as improved BW when compared with controls and each product individually. These data address both animal welfare and food safety concerns faced by the poultry industry.

Ketosis and appetite-mediating nutrients and hormones after weight loss

BACKGROUND/OBJECTIVES

Diet-induced weight loss is accompanied by compensatory changes, which increase appetite and encourage weight regain. There is some evidence that ketogenic diets suppress appetite. The objective is to examine the effect of ketosis on a number of circulating factors involved in appetite regulation, following diet-induced weight loss.

SUBJECTS/METHODS

Of 50 non-diabetic overweight or obese subjects who began the study, 39 completed an 8-week ketogenic very-low-energy diet (VLED), followed by 2 weeks of reintroduction of foods. Following weight loss, circulating concentrations of glucose, insulin, non-esterified fatty acids (NEFA), β-hydroxybutyrate (BHB), leptin, gastrointestinal hormones and subjective ratings of appetite were compared when subjects were ketotic, and after refeeding.

RESULTS

During the ketogenic VLED, subjects lost 13% of initial weight and fasting BHB increased from (mean±s.e.m.) 0.07±0.00 to 0.48±0.07 mmol/l (P<0.001). BHB fell to 0.19±0.03 mmol/l after 2 weeks of refeeding (P<0.001 compared with week 8). When participants were ketotic, the weight loss induced increase in ghrelin was suppressed. Glucose and NEFA were higher, and amylin, leptin and subjective ratings of appetite were lower at week 8 than after refeeding.

CONCLUSIONS

The circulating concentrations of several hormones and nutrients which influence appetite were altered after weight loss induced by a ketogenic diet, compared with after refeeding. The increase in circulating ghrelin and subjective appetite which accompany dietary weight reduction were mitigated when weight-reduced participants were ketotic.

Short-term carbohydrate-restricted diet for weight loss in severely obese women

BACKGROUND

Weight loss in bariatric pre-surgery period reduces surgical complications, surgery time, blood loss, and length of hospital stay. Carbohydrate-restricted diets have been used as an alternative for weight loss. We tested the efficacy of a low-calorie carbohydrate-restricted diet (RD) for short-term weight loss in women with severe obesity and evaluate its metabolic effects in relation to a conventional low-calorie diet (CD).

METHODS

The subjects received a 1,200-kcal diet with or without carbohydrate restriction for a period of 1 week in the hospital. Nineteen obesity class III women were distributed into two groups: experimental (n = 10) and control (n = 9). The following variables were assessed at the beginning and end of the study: anthropometric measurements, body composition, resting energy expenditure, substrate oxidation, and biochemical tests.

RESULTS

Compared with CD, RD led to larger weight loss (2.6 and 4.4 kg, respectively; p = 0.01) and waist circumference reduction (p < 0.01). Among the assessed biochemical indicators, only plasma and urine acetone levels were different (p < 0.01); higher values were found in the experimental group with no symptoms and other diet-related complaints. There was also a significant decrease in triglycerides and carbohydrate oxidation, as well as a significant enhancement in lipid oxidation in the RD group.

CONCLUSION

Short-term RD was more efficient than CD regarding quick weight loss and waist circumference reduction, which may favor gastroplasty. Also, RD did not lead adverse metabolic effects.

Nutrition and acne: therapeutic potential of ketogenic diets

The influence of nutrition on skin health is a growing research area but the findings of various studies on the effect of diet on the development of acne have often been contradictory. The general opinion among researchers has oscillated between two different, opposing positions: that diet either is or is not a key factor for acne development. This review examines the evidence supporting an influence of various dietary components on the development of acne particularly focusing on the role played by carbohydrates. The physiological and biochemical effects of the ketogenic diet are examined from this perspective and mechanisms will be proposed via which this type of diet could have a role in the treatment of acne.

Low-carbohydrate diets: a matter of love or hate

Low-carbohydrate diets (LChD) have become very popular among the general population. These diets have been used to lose body weight and to ameliorate various abnormalities like diabetes, nonalcoholic fatty liver disease, polycystic ovary syndrome, narcolepsy, epilepsy, and others. Reports suggest that body weight reduction and glycemic control could be attained while following LChD. However, these advantages are more notably found in short periods of time consuming an LChD. Indeed, the safety and efficacy of the latter diets in the long term have not been sufficiently explored. In contrast to what has been proposed, other mentioned pathologies are not improved or are even worsened by carbohydrate restriction. Therefore, the aim of this review is to define the concept of LChD and to explain their clinical effects in the short and long term, their influence on metabolism, and the opinion of nutrition or health authorities. Finally, evincing the research gaps of LChD that are here exposed will later allow us to reach a consensus with regard to their utilization.

Lifestyle intervention leading to moderate weight loss normalizes postprandial triacylglycerolemia despite persisting obesity

Obesity is associated with impaired postprandial triacylglycerolemia, an independent risk factor for cardiovascular disease. Given that obesity is hard to treat, efforts should focus on treating its comorbidities. We aimed to investigate whether moderate weight loss normalizes postprandial triacylglycerol (TAG) concentrations, in the absence of the acute effects of negative energy balance. For this purpose, postprandial lipemia was investigated in eight obese but otherwise healthy, sedentary men (age: 41.3 ± 4.1 years, BMI: 36.5 ± 1.6 kg·m(-2)), once before and again after a 10% weight loss followed by ≥4 weeks of weight maintenance, and was compared with that of eight age-matched healthy lean men (BMI: 24.7 ± 0.6 kg·m(-2)). Dietary intervention consisted of reduced carbohydrate and saturated fat intake and increased monounsaturated fat intake. Obese volunteers were advised to increase physical activity using pedometers to record daily activity. Postprandial triacylglycerolemia after weight loss was reduced by 27-46% (P < 0.05), and became similar to that of lean men despite persisting obesity (BMI after weight loss: 32.9 ± 1.5 kg·m(-2)). Reduction in postprandial TAG responses was inversely correlated with the decrease in postprandial insulin sensitivity index (ISI) after weight loss (r = -0.714, P = 0.047). We conclude that moderate weight loss induced by a low-carbohydrate and saturated fat diet and a slight increase in daily physical activity normalizes postprandial triacylglycerolemia in obese men, independently of acute diet-induced negative energy balance, and possibly through enhancement of insulin action.

A ketogenic diet impairs energy and glucose homeostasis by the attenuation of hypothalamic leptin signaling and hepatic insulin signaling in a rat model of non-obese type 2 diabetes

Ketogenic diets (KTD) are reported to have beneficial effects on the regulation of energy and glucose homeostasis, but remain controversial. We investigated the effects of KTD and ketones on insulin resistance and secretion in non-obese type 2 diabetic rats and their mechanism. KTD (82% energy as fat), intraperitoneal injection of β-hydroxybutyrate (IHB; 150 mg/kg bw/12 h) with a control diet (COD; 20% energy as fat) or saline injection with COD was given to 90% pancreatectomized (Px) diabetic rats for five weeks. KTD increased epididymal fat pads and serum leptin levels without increasing energy intake, but IHB decreased them. KTD, but not IHB, attenuated hypothalamic signal transducer and activator of transcription 3 and 5'-adenosine monophosphate-activated protein kinase (AMPK) phosphorylation in KTD. Serum glucagon levels were markedly higher in the KTD group than in other groups. During an oral glucose tolerance test, serum glucose levels slowly increased until 80 min in the KTD group and then decreased very slowly. Insulin secretion capacity during a hyperglycemic clamp was significantly lower in the IHB group than in other groups. However, a euglycemic hyperinsulinemic clamp revealed that KTD decreased glucose infusion rates and increased hepatic glucose output in hyperinsulinemic states while IHB had opposite effects to KTD. The increased hepatic glucose output in KTD was associated with increased hepatic phosphoenolpyruvate carboxykinase expression through attenuated tyrosine phosphorylation of IRS2 and phosphorylation of Akt(Ser473). Hepatic AMPK(Thr172) phosphorylation was reduced in KTD. In conclusion, KTD impairs energy and glucose homeostasis by exacerbating insulin resistance and attenuating hypothalamic leptin signaling in non-obese type 2 diabetic rats. These changes are not associated with increased serum ketone levels.

Ketonuria after fasting may be related to the metabolic superiority

Obese individuals are less able to oxidize fat than non-obese individuals. Caloric reduction or fasting can detect ketonuria. We investigated the differences of metabolic parameters in the presence of ketonuria after a minimum 8 hr fast in a cross-sectional analysis of 16,523 Koreans (6,512 women and 10,011 men). The relationship between the presence of ketonuria of all subjects and prevalence of obesity, central obesity, metabolic syndrome, and obesity-related metabolic parameters were assessed. The ketonuria group had lower prevalence of obesity, central obesity, and metabolic syndrome than the non-ketonuria group. In addition, all metabolic parameters (including body weight, waist circumference, blood glucose, high-density lipoprotein, triglyceride, blood pressure, and insulin) were favorable in the ketonuria group than in the non-ketonuria group, even after adjustment for age, tobacco use, and alcohol consumption. The odds ratios of having obesity (odds ratio [OR]=1.427 in women, OR=1.582 in men, P<0.05), central obesity (OR=1.675 in women, OR=1.889 in men, P<0.05), and metabolic syndrome (OR=3.505 in women, OR=1.356 in men, P<0.05) were increased in the non-ketonuria group compared to the ketonuria group. The presence of ketonuria after at least an 8 hr fast may be indicative of metabolic superiority.

State of the Art Reviews: Relationship Between Diet/ Physical Activity and Health

Obesity and 4 of the leading causes of death—heart disease, cancer, stroke, and type 2 diabetes mellitus—are related to lifestyle. The combination of a healthy weight, prudent diet, and daily physical activity clearly plays a role in primary, secondary, and tertiary prevention of these and other chronic diseases. Because nearly 65% of the adult population is overweight or obese, weight loss and maintenance are central to this review article. Improved lipid profiles, blood pressure, insulin sensitivity, and euglycemia are associated with weight loss or a normal body weight; thus, maintaining a healthy weight is a universal recommendation for health. The methods for improving lifestyle described in the section on obesity include assessing nutritional status and stages of change of the client, setting realistic goals, eating a diet high in fruits and vegetables with low-fat sources of dairy and protein, and achieving appropriate physical activity levels. The importance of physicians discussing weight with clients and vice versa is stressed. The common features of lifestyle-related diseases make them amenable to similar lifestyle interventions.

Popular weight-loss diets: from evidence to practice

The increasing number of overweight and obese individuals has become one of the leading public health concerns in many countries around the world. Concomitant with this increase in the prevalence of obesity has been the rise in the number of weight-loss diets, many of which alter macronutrient composition, but with the majority focused on carbohydrate restriction. Low-carbohydrate diets are attractive because they promise rapid weight loss without having to count calories and compromise the consumption of many palatable foods. By contrast, traditional dietary recommendations for weight loss endorse a fat-restricted and calorie-restricted diet high in complex carbohydrates. Evidence indicates that low-carbohydrate diets could be better in terms of short-term weight loss relative to traditional low-fat diets, but little is known about their long-term utility and safety. Diets based on the traditional Mediterranean dietary pattern are becoming increasingly popular because of their healthful benefits, particularly regarding cardiovascular outcomes. Mediterranean diets encourage consumption of a variety of palatable foods, optimizing adherence and sustainability. In this Review we discuss the current evidence on the efficacy of low-fat, low-carbohydrate and Mediterranean dietary patterns for weight loss, their potential mechanisms of action and important clinical considerations.

From birth to adolescence: Vienna 2005 European Childhood Obesity Group International Workshop

BACKGROUND

In the last 15 y there has been a tremendous increase in the number of studies on pediatric obesity looking at epidemiology, health-related risks, etiology, methodology and treatment. During the early 1990s, the European Childhood Obesity Group (ECOG) was born as a group of scientists' expert in the field of pediatric obesity. ECOG this year celebrates the approach to early maturity with an excited and omni-comprehensive program developing through eight different tracks.

METHODS

Comments on different 'key' papers in each of the eight tracks.

RESULTS

The eight tracks were (1) Nutrition requirements and food habits, (2) physical activity, (3) prevention and political actions/strategies, (4) diabetes, (5) metabolism, (6) psychology, (7) pathology, and (8) treatment with emphasis on drugs.

CONCLUSION

Looking at the overall picture of the ECOG workshop we could conclude that despite the fact that childhood obesity is a crisis facing worldwide youth, it is necessary that action to control it must be taken now. All the six relevant levels (ie, family, schools, health professionals, government, industry and media) could be involved in prevention of child and adolescent obesity.