Clinical update: the low-glycaemic-index diet

Factors Associated With Treatment Adherence to a Lifestyle Intervention Program for Children With Obesity: The Experience of a Large Tertiary Care Pediatric Hospital

Early dropout and treatment adherence are main challenges in the treatment of children with obesity. The aim of this study was to identify factors associated with attrition and adherence to weight loss intervention program. We retrospectively reviewed the medical records of all the children who entered the program for pediatric weight loss over 5 years and retrieved demographic and clinical characteristics. Attrition and adherence were documented. Ninety-two of the 248 enrolled children (52% women, mean age 11.1 ± 3.9 years, mean body mass index 31.1 ± 7 kg/m²) dropped out (37%). Dropping out correlated with male sex, low parental education, and self-referral to the clinic (P < .05 for all). Adherence correlated with older age and the mother's healthy lifestyle (P < .05 for all). Sex, parental education, and referral source may predict treatment attrition. Early recognition of children at risk of attrition may help to facilitate better care of those children.

The Glycemic Response to Infant Formulas: A Randomized Clinical Trial

Background: Commercial infant formulas attempt to imitate human milk’s unique composition. However, lactose-free and milk protein-free formulas are often chosen due to medical reasons or personal preferences. The aim of this study was to determine the glycemic and insulinemic indices of a variety of infant formulas. Methods: We conducted a three-arm, randomized, double-blind, crossover study. Participants were 25–40-year-old healthy adults. Three commercial infant formulas (cow’s milk protein-based [“standard”], soy protein-based, and lactose-free) were randomly given to each participant. Glycemic and insulinemic responses were determined and compared between the three formulas. Results: Twenty subjects were enrolled (11 females/9 males, mean age 32.8 ± 2.9 years). No significant difference was found in the glycemic index between the three formulas (21.5, 29.1, and 21.5 for the standard, soy protein-based, and lactose-free formulas, respectively, p = 0.21). However, maximal glucose levels were significantly higher for the soy protein-based formula compared to both the standard and lactose-free formulas (111.5 compared to 101.8 and 105.8 mg/dL, respectively, p = 0.001). Conclusion: Cow’s milk protein-based, soy protein-based, and lactose-free formulas have a similar glycemic index. However, soy protein-based formula produced a significantly higher increase in postprandial glucose levels. The implication and biological significance of these results have yet to be determined.

The association between carbohydrate quality index and anthropometry, blood glucose, lipid profile and blood pressure in people with type 1 diabetes mellitus: a cross-sectional study in Iran

BACKGROUND & AIM

Both types and amounts of dietary carbohydrates have always been issues of discussion in diabetes mellitus. Therefore, this study aimed to investigate the association between carbohydrate quality index (CQI) and anthropometry, fasting blood glucose (FBG), lipid profile, systolic (SBP), and diastolic (DBP) blood pressure in adults with type 1 diabetes mellitus (T1DM).

MATERIALS & METHODS

This was a cross-sectional study conducted on 261 adults with T1DM aged 17-36 years who referred to the Iranian Diabetes Association or Diabetes Clinic of Tehran University of Medical Sciences. Dietary data were collected using a 147-item food frequency questionnaire (FFQ). The CQI was calculated from the three indices including dietary fiber, glycemic index (GI), and solid carbohydrates/total carbohydrates ratio. The weight, height, waist circumference, physical activity, HcA1c, SBP, DBP of all participants were measured. Biochemical assessment including serum lipids and FBG levels were analyzed on 81 individuals.

RESULTS

Participants with a higher CQI had a lower body weight, GI, glycemic load, energy, and macronutrient intake (p < 0.05). In addition, after adjustment for age, sex, duration of diabetes, body mass index, physical activity, and energy intake, the lowest level of glycated hemoglobin A1c (HbA1c) was observed in the third tertile of CQI (β = -0.2; SE = 0.1; p-trend = 0.04). No significant association was observed with respect to CQI with FBG, lipid profile, and blood pressure.

CONCLUSION

It was concluded that there was an inverse association between CQI and HbA1c. No significant association was found with respect to CQI with FBG, lipid profile and blood pressure.

Chickpeas suppress postprandial blood glucose concentration, and appetite and reduce energy intake at the next meal

The current study was designed to explore the beneficial properties of chickpeas consumption on suppressing appetite, excessive blood glucose excursions, and energy intake (EI) from a subsequent meal. Two caloric preloaded foods, chickpeas, and white bread were compared to water control, fed to healthy female subjects at equal energy density, volume, and available carbohydrate content in two experiments spanning over 60 and 120 min. Blood glucose was measured by a portable glucometer and satiety by using a visual analogue scale questionnaire at baseline and every 15 up to 60 min in both experiments and then every 30 until 120 min in Experiment 2 after the preloads ingestion. A test meal was served at the end of both experiments to calculate EI and percent energy compensation (%EC). The results suggest a reduction of 29-36% in blood glucose concentration, and 83-98% EC after the chickpeas in Experiments 1 and 2 respectively compared to white bread. The average appetite showed a positive association with EI. We conclude that the consumption of chickpeas is beneficial on glycemic control and may help in body weight management through suppressing appetite and energy intake.

The effect of healthy dietary consumption on executive cognitive functioning in children and adolescents: a systematic review

A systematic review was conducted to evaluate whether healthier dietary consumption among children and adolescents impacts executive functioning. PubMed, Education Resources Information Center, PsychINFO and Thomson Reuters’ Web of Science databases were searched, and studies of executive functioning among children or adolescents aged 6–18 years, which examined food quality, macronutrients and/or foods, were included. Study quality was also assessed. In all, twenty-one studies met inclusion criteria. Among the twelve studies examining food quality (n 9) or macronutrient intakes (n 4), studies examining longer-term diet (n 6) showed positive associations between healthier overall diet quality and executive functioning, whereas the studies examining the acute impact of diet (n 6) were inconsistent but suggestive of improvements in executive functioning with better food quality. Among the ten studies examining foods, overall, there was a positive association between healthier foods (e.g. whole grains, fish, fruits and/or vegetables) and executive function, whereas less-healthy snack foods, sugar-sweetened beverages and red/processed meats were inversely associated with executive functioning. Taken together, evidence suggests a positive association between healthy dietary consumption and executive functioning. Additional studies examining the effects of healthier food consumption, as well as macronutrients, on executive functioning are warranted. These studies should ideally be conducted in controlled environments and use validated cognitive tests.

Lifestyle-induced decrease in fat mass improves adiponectin secretion in obese adults

PURPOSE

Several studies have identified relationships between weight loss and adipokine levels; however, none have looked at the combined effect of aerobic exercise training with the consumption of a low- or a high-glycemic diet. We examined the effects of 12 wk of aerobic exercise combined with either a low-glycemic index diet (∼40 U) plus exercise (LoGIX) or a high-glycemic index diet (∼80 U) diet plus exercise (HiGIX) on plasma leptin and adiponectin (total and high molecular weight [HMW]) in 27 older obese adults (age = 65 ± 0.5 yr, body mass index = 34.5 ± 0.7 kg·m).

METHODS

Insulin sensitivity was calculated from an oral glucose tolerance test. Fasting HMW adiponectin and leptin were quantified from plasma samples obtained before the insulin sensitivity index obtained from the oral glucose tolerance test. Glucose and insulin measures were obtained before and every 30 min during the test. Dual-energy x-ray absorptiometry and computerized tomography were used to determine body composition and to quantify subcutaneous and visceral abdominal adiposity, respectively.

RESULTS

Fasting leptin was significantly decreased in both groups (LoGIX: preintervention = 33.8 ± 4.7, postintervention = 19.2 ± 4.5; HiGIX: preintervention = 27.9 ± 4.2, postintervention = 11.9 ± 2.2 ng·mL; P = 0.004), and HMW adiponectin was significantly increased (LoGIX: preintervention = 1606.9 ± 34.6, postintervention = 3502.3 ± 57; HiGIX: preintervention = 3704.8 ± 38.1, postintervention = 4284.3 ± 52.8 pg·mL; P = 0.003) after the 12-wk intervention. Total body fat was reduced after both interventions. Visceral fat mass was inversely correlated with HMW adiponectin, whereas subcutaneous fat correlated with leptin.

CONCLUSIONS

The data suggest that exercise training, independent of dietary glycemic index, favorably alters HMW adiponectin and leptin secretion and that a reduction in visceral fat mass is a key factor regulating HMW adiponectin in older obese persons.

A randomized controlled trial to investigate the impact of a low glycemic index (GI) diet on body mass index in obese adolescents

BACKGROUND

The role of a low glycemic index (GI) diet in the management of adolescent obesity remains controversial. In this study, we aim to evaluate the impact of low GI diet versus a conventional Chinese diet on the body mass index (BMI) and other obesity indices of obese adolescents.

METHODS

Obese adolescents aged 15-18 years were identified from population-recruited, territory-wide surveys. Obesity was defined as BMI ≥95th percentile of Hong Kong local age- and sex-specific references. Eligible subjects were randomized to either an intervention with low GI diet (consisting of 45-50% carbohydrate, 30-35% fat and 15-20% protein) or conventional Chinese diet as control (consisting of 55-60% carbohydrate, 25-30% fat and 10-15% protein). We used random intercept mixed effects model to compare the differential changes across the time points from baseline to month 6 between the 2 groups.

RESULTS

104 obese adolescents were recruited (52 in low GI group and 52 in control group; 43.3% boys). Mean age was 16.7 ± 1.0 years and 16.8 ±1.0 years in low GI and control group respectively. 58.7% subjects completed the study at 6 months (65.4% in low GI group and 51.9% in control group). After adjustment for age and sex, subjects in the low GI group had a significantly greater reduction in obesity indices including BMI, body weight and waist circumference (WC) compared to subjects in the control group (all p <0.05). After further adjustment for physical activity levels, WC was found to be significantly lower in the low GI group compared to the conventional group (p = 0.018).

CONCLUSION

Low GI diet in the context of a comprehensive lifestyle modification program may be an alternative to conventional diet in the management of obese adolescents.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Ref. No: NCT01278563.

Nutrition as a link between obesity and cardiovascular disease: how can we stop the obesity epidemic?

Overweight and obesity are associated with excess cardiovascular risk. To reduce cardiovascular risk at the population level, the prevention of overweight and obesity is key. This requires adoption of a healthy lifestyle, including less inactivity and more moderate-to-vigorous physical activity, and a healthy diet. Diet composition may facilitate weight gain prevention and weight loss. Effects of dietary fats, carbohydrates and proteins will be discussed in this context. Current evidence indicates that moderation of the intake of (saturated) fat, a moderate increase in protein content of the diet, a replacement of refined grain/high glucose index (GI) by whole-grain/low GI carbohydrates and limitation of the consumption of calorically-sweetened beverages are likely to facilitate weight control.

A low-glycemic-load versus low-fat diet in the treatment of fatty liver in obese children

BACKGROUND

Fatty liver is highly prevalent among obese children and represents a major risk factor for chronic liver diseases and severe metabolic complications.

METHODS

We randomly assigned 17 obese children 8-17 years of age with fatty liver to either an experimental low-glycemic-load or conventional low-fat diet for 6 months. Participants in both groups received nutrition education and behavioral counseling of equal intensity. The primary outcome was hepatic lipid content measured by proton magnetic resonance spectroscopy. Secondary outcomes included change in visceral fat, BMI, anthropometrics, alanine aminotransferase (ALT), and insulin resistance.

RESULTS

A total of 16 participants completed the study. Reported glycemic load decreased in the low-glycemic-load group and reported dietary fat decreased in the low-fat group. At baseline, liver fat was 23.8% [standard deviation (SD) 12.2] in the low-glycemic-load group and 29.3% (14.1) in the low-fat group. Liver fat decreased substantially in both groups at 6 months expressed as absolute percentage change, with no between-group differences [-8.8 (standard error (SE) 4.1) vs. -10.5 (3.7)%, respectively, p=0.76 for group×time interaction]. Secondary outcomes also improved on both diets, with no between-group differences. Baseline and change in ALT were strongly associated with hepatic fat content.

CONCLUSIONS

Weight-reducing diets focused either on glycemic load or dietary fat improved hepatic steatosis over 6 months. Additional research is needed to determine whether these diets differ in effectiveness over the long term.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00480922.

Methodology for adding glycemic index to the National Health and Nutrition Examination Survey nutrient database

Generating valid estimates of dietary glycemic index (GI) and glycemic load (GL) has been a challenge in nutritional epidemiology. The methodologic issues may have contributed to the wide variation of GI/GL associations with health outcomes observed in existing literature. We describe a standardized methodology for assigning GI values to items in the National Health and Nutrition Examination Survey (NHANES) nutrient database using the new International Tables to develop research-driven, systematic procedures and strategies to estimate dietary GI/GL exposures of a nationally representative population sample. Nutrient databases for NHANES 2003-2006 contain information on 3,155 unique foods derived from the US Department of Agriculture National Nutrient Database for Standard Reference versions 18 and 20. Assignment of GI values were made to a subset of 2,078 carbohydrate-containing foods using systematic food item matching procedures applied to 2008 international GI tables and online data sources. Matching protocols indicated that 45.4% of foods had identical matches with existing data sources, 31.9% had similar matches, 2.5% derived GI values calculated with the formula for combination foods, 13.6% were assigned a default GI value based on low carbohydrate content, and 6.7% of GI values were based on data extrapolation. Most GI values were derived from international sources; 36.1% were from North American product information. To confirm data assignments, dietary GI and GL intakes of the NHANES 2003-2006 adult participants were estimated from two 24-hour recalls and compared with published studies. Among the 3,689 men and 4,112 women studied, mean dietary GI was 56.2 (men 56.9, women 55.5), mean dietary GL was 138.1 (men 162.1, women 116.4); the distribution of dietary GI was approximately normal. Estimates of population GI and GL compare favorably with other published literature. This methodology of adding GI values to an existing population nutrient database utilized systematic matching protocols and the latest comprehensive data sources on food composition. The database can be applied in clinical and survey research settings where there is interest in estimating individual and population dietary exposures and relating them to health outcomes.

Growth in Long-Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency

Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency is an inborn error of fatty acid metabolism that affects the degradation of long chain fatty acids and causes insufficient energy production and accumulation of toxic intermediates. The treatment consists of a diet low in fat, with supplementation of medium-chain triglycerides that bypass the metabolic block. In addition, frequent feeds and extra carbohydrates are given during febrile illnesses to reduce lipolysis. Hence, this diet differs from the general dietary recommendations for growing children. Furthermore, the Swedish dietary instructions for fat intake in LCHAD deficiency are given in grams, which differ from most guidelines that recommend fat intake as percentage shares of total caloric intake.

AIMS

To assess growth in patients with LCHAD deficiency, in relation to dietary treatment and to evaluate if overweight/obesity is more common than in the normal population.

RESULTS

The growth velocity showed acceleration after diagnosis and the start of treatment, followed by a period of stable or decelerated growth. The majority of the patients developed overweight to a greater extent than children without LCHAD deficiency. Several patients also went through a phase of obesity. Data on final height (FH) showed that three out of five patients had grown according to their genetic potential.

CONCLUSIONS

Regular and frequent follow-up and careful monitoring of weight are essential to avoid the development of overweight and obesity. The Swedish dietary instructions defining fat intake in total grams per day may be an alternative approach to achieve a moderate total caloric intake.

Overview of paediatric obesity for the paediatric mental health provider

Childhood obesity represents a significant challenge for paediatric healthcare delivery. As obesity rates increase, obese children and adolescents are at significant risk for the development of a myriad of medical and surgical problems as well as mental health problems. Moreover, children with mental health problems are increasingly presenting to their psychiatrists with obesity. Treatment of paediatric obesity requires a multidisciplinary approach with incorporation of the family into the treatment plan although still typically only offering suboptimal results. Paediatric providers from all disciplines should focus efforts primarily on obesity prevention and encouragement of healthy lifestyles, while incorporating treatment for obesity when such efforts fail. The goals of this article are to provide an overview of the epidemiology, pathophysiology, genetics, clinical features and treatment strategies for paediatric obesity.

Weight loss and improvements in fatigue in systemic lupus erythematosus: a controlled trial of a low glycaemic index diet versus a calorie restricted diet in patients treated with corticosteroids

Background: Patients with systemic lupus erythematosus (SLE) may require prolonged periods of corticosteroid therapy which lead to excessive weight gain and increased cardiovascular risk. Objective: To assess the utility of a low glycaemic index diet in patients with corticosteroid dependent SLE in achieving weight loss and improving glycaemic control. Design: A total of 23 women were enrolled in a 6 week study. All had mild, stable SLE, were receiving corticosteroids and had a body mass index > 25 kg/m2. Subjects were randomly assigned to a low glycaemic index (Low GI) diet or a calorie restricted (Low Cal) diet. The primary end point was weight loss. Secondary end points included tolerability of diet, bio-markers of cardiovascular risk, disease activity, fatigue and sleep quality. Results: Weight loss in both treatment groups was significant (mean ± SD: Low GI diet 3.9 ± 0.9 kg; Low Cal diet 2.4 ± 2.2 kg, p < 0.01 from baseline in each group). There were also significant improvements in waist and hip measurements. However, the difference in weight loss and waist and hip measurements between the two diet groups was not statistically significant. There was a statistically significant reduction in Fatigue Severity Scale in both diet groups, ( p < 0.03). Both Low GI and Low Cal diets were well tolerated, resulting in no serious adverse effects or increase in disease activity. Conclusion: Significant weight loss is achievable over 6 weeks in a diet-specific trial in subjects with stable SLE, who are on low dose prednisolone. Both diets were equally tolerable, and did not cause flares in disease activity. Our results suggest that dietary manipulation may significantly improve fatigue in subjects with SLE.

Reduced carbohydrate diet to improve metabolic outcomes and decrease adiposity in obese peripubertal African American girls

OBJECTIVE

Obesity prevalence among African American (AA) girls is higher than that in other groups. Because typical energy-restriction obesity treatment strategies have had limited success, alterations in macronutrient composition may effectively improve metabolic outcomes in this population and affect future body composition trajectories. The objective was to evaluate the efficacy of a moderately restricted carbohydrate (CHO) versus a standard CHO diet on weight/fat loss and metabolic parameters in overweight/obese AA girls ages 9 to 14 years.

METHODS

A total of 26 AA girls (ranging from 92nd body mass index percentile and above) were assigned to either a reduced- (SPEC: 42% energy from CHO, n = 12) or a standard- (STAN: 55% of energy from CHO, n = 14) CHO diet (protein held constant) for 16 weeks. All of the meals were provided and clinically tailored to meet the estimated energy requirements (resting energy expenditure × 1.2 in eucaloric phase and resting energy expenditure × 1.2 - 1000 kcal in energy deficit phase). The first 5 weeks encompassed a eucaloric phase evaluating metabolic changes in the absence of weight change. The subsequent 11 weeks were hypocaloric (1000 kcal/day deficit) to promote weight/fat loss. Meal tests were performed during the eucaloric phase for metabolic analyses. Dual-energy x-ray absorptiometry was used to evaluate body composition.

RESULTS

Both groups experienced reductions in weight/adiposity, but the difference did not reach significance. The solid meal test indicated improved glucose/insulin homeostasis on the SPEC diet up to 3 hours postingestion. In addition, significantly lower triglycerides (P < 0.001) were observed on the SPEC diet.

CONCLUSIONS

Dietary CHO reduction favorably influences metabolic parameters but did not result in greater weight/fat loss relative to a standard diet in obese AA girls. Future research is needed to determine long-term effectiveness of a reduced CHO diet on glucose and insulin homeostasis and how it may apply to weight maintenance/fat loss during development alone and/or in combination with additional weight loss/metabolic improvement strategies.

Essentials of healthy eating: a guide

Enough solid evidence now exists to offer women several fundamental strategies for healthy eating. They include emphasizing healthful unsaturated fats, whole grains, good protein "packages," and fruits and vegetables; limiting consumption of trans and saturated fats, highly refined grains, and sugary beverages; and taking a multivitamin with folic acid and extra vitamin D as a nutritional safety net. A diet based on these principles is healthy through virtually all life stages, from young adulthood through planning for pregnancy, pregnancy, and on into old age.

Dietary hyperglycemia, glycemic index and metabolic retinal diseases

The glycemic index (GI) indicates how fast blood glucose is raised after consuming a carbohydrate-containing food. Human metabolic studies indicate that GI is related to patho-physiological responses after meals. Compared with a low-GI meal, a high-GI meal is characterized with hyperglycemia during the early postprandial stage (0-2h) and a compensatory hyperlipidemia associated with counter-regulatory hormone responses during late postprandial stage (4-6h). Over the past three decades, several human health disorders have been related to GI. The strongest relationship suggests that consuming low-GI foods prevents diabetic complications. Diabetic retinopathy (DR) is a complication of diabetes. In this aspect, GI appears to be useful as a practical guideline to help diabetic people choose foods. Abundant epidemiological evidence also indicates positive associations between GI and risk for type 2 diabetes, cardiovascular disease, and more recently, age-related macular degeneration (AMD) in people without diabetes. Although data from randomized controlled intervention trials are scanty, these observations are strongly supported by evolving molecular mechanisms which explain the pathogenesis of hyperglycemia. This wide range of evidence implies that dietary hyperglycemia is etiologically related to human aging and diseases, including DR and AMD. In this context, these diseases can be considered as metabolic retinal diseases. Molecular theories that explain hyperglycemic pathogenesis involve a mitochondria-associated pathway and four glycolysis-associated pathways, including advanced glycation end products formation, protein kinase C activation, polyol pathway, and hexosamine pathway. While the four glycolysis-associated pathways appear to be universal for both normoxic and hypoxic conditions, the mitochondria-associated mechanism appears to be most relevant to the hyperglycemic, normoxic pathogenesis. For diseases that affect tissues with highly active metabolism and that frequently face challenge from low oxygen tension, such as retina in which metabolism is determined by both glucose and oxygen homeostases, these theories appear to be insufficient. Several lines of evidence indicate that the retina is particularly vulnerable when hypoxia coincides with hyperglycemia. We propose a novel hyperglycemic, hypoxia-inducible factor (HIF) pathway, to complement the current theories regarding hyperglycemic pathogenesis. HIF is a transcription complex that responds to decrease oxygen in the cellular environment. In addition to playing a significant role in the regulation of glucose metabolism, under hyperglycemia HIF has been shown to increase the expression of HIF-inducible genes, such as vascular endothelial growth factor (VEGF) leading to angiogenesis. To this extent, we suggest that HIF can also be described as a hyperglycemia-inducible factor. In summary, while management of dietary GI appears to be an effective intervention for the prevention of metabolic diseases, specifically AMD and DR, more interventional data is needed to evaluate the efficacy of GI management. There is an urgent need to develop reliable biomarkers of exposure, surrogate endpoints, as well as susceptibility for GI. These insights would also be helpful in deciphering the detailed hyperglycemia-related biochemical mechanisms for the development of new therapeutic agents.

Effective dietary therapies for pediatric obesity treatment

Dietary changes combined with behavioral management techniques, such as short term attainable goal setting, is effective for treating pediatric obesity. Dietary interventions combined with increasing physical activity are essential for weight loss. We review the basic nutrition concepts that should be employed to treat pediatric obesity and summarize the available literature on effective dietary interventions that have been studied to date.

Dietary energy density in relation to subsequent changes of weight and waist circumference in European men and women

Background

Experimental studies show that a reduction in dietary energy density (ED) is associated with reduced energy intake and body weight. However, few observational studies have investigated the role of ED on long-term weight and waist circumference change.

Methods and Principal Findings

This population-based prospective cohort study included 89,432 participants from five European countries with mean age 53 years (range: 20–78 years) at baseline and were followed for an average of 6.5 years (range: 1.9–12.5 years). Participants were free of cancer, cardiovascular diseases and diabetes at baseline. ED was calculated as the energy intake (kcal) from foods divided by the weight (g) of foods. Multiple linear regression analyses were performed to investigate the associations of ED with annual weight and waist circumference change.

Mean ED was 1.7 kcal/g and differed across study centers. After adjusting for baseline anthropometrics, demographic and lifestyle factors, follow-up duration and energy from beverages, ED was not associated with weight change, but significantly associated with waist circumference change overall. For 1 kcal/g ED, the annual weight change was −42 g/year [95% confidence interval (CI): −112, 28] and annual waist circumference change was 0.09 cm/year [95% CI: 0.01, 0.18]. In participants with baseline BMI<25 kg/m², 1 kcal/g ED was associated with a waist circumference change of 0.17 cm/year [95% CI: 0.09, 0.25].

Conclusion

Our results suggest that lower ED diets do not prevent weight gain but have a weak yet potentially beneficial effect on the prevention of abdominal obesity as measured by waist circumference.

Effects of a high-fat, low- versus high-glycemic index diet: retardation of insulin resistance involves adipose tissue modulation

Beneficial effects of low glycemic index (GI) diets in rodents have been studied using healthy low-fat diets, while the effects might be different on high-fat diets inducing progression of insulin resistance. We fed C57BL/6J male mice high-fat low/high-GI (LGI/HGI) diets for 13 wk. Glucose and insulin tolerance and serum substrates, including adipokines, were measured longitudinally. The LGI group showed a significantly higher glucose tolerance from wk 2 onwards, which was supported by lower serum insulin and free fatty acids levels at 8 wk, and a tendency for lower leptin levels, while resistin levels remained similar. At 11 wk, when differences in serum resistin started to increase, differences in serum insulin were diminished. Although food intake was similar throughout the study, body weights and epididymal adipose tissue mass became significantly lower in the LGI group at necropsy. Several serum substrates and adipose tissue leptin mRNA levels, as analyzed by Q-PCR, were, again, significantly lower, whereas adiponectin mRNA levels were higher. Taken together, an LGI high-fat diet maintains higher glucose tolerance and insulin sensitivity via adipose tissue modulation solely because of a difference in the type of carbohydrate, supporting a nutritional approach in the fight against insulin resistance.

Inflammation markers are modulated by responses to diets differing in postprandial insulin responses in individuals with the metabolic syndrome

BACKGROUND

Inflammation may be a mechanism by which high postprandial insulin and glucose responses increase the risk of type 2 diabetes mellitus.

OBJECTIVE

We hypothesized that dietary carbohydrates characterized by different postprandial insulin responses may differentially modify cytokine concentrations in plasma and gene expression in subcutaneous adipose tissue.

DESIGN

Individuals (n = 47) with the metabolic syndrome were randomly assigned to a 12-wk diet with oat and wheat bread and potato (high postprandial insulin response) or rye bread and pasta (low postprandial insulin response). Postprandial glucose and insulin responses to the oat and wheat bread meal and to the rye bread meal were determined in 19 individuals before intervention.

RESULTS

During the 12-wk diet, the change in the gene expression of interleukin (IL)-10 receptor alpha and tumor necrosis factor-alpha in subcutaneous adipose tissue differed between the groups (P = 0.002 and P = 0.083, respectively). Moreover, the change in fasting plasma concentrations of IL-1beta and IL-6 differed between the groups (P = 0.020 and P = 0.055, respectively). In the postprandial challenge, the insulin response to the rye bread meal was lower than that to the oat and wheat bread meal (P < 0.001), whereas there were no differences in the mean blood glucose response. In contrast, plasma glucose concentrations decreased more below fasting concentrations 2.5-3 h after the oat and wheat bread meal than after the rye bread meal. A late postprandial rebound of free fatty acids was detected after the oat and wheat bread meal (P = 0.048).

CONCLUSIONS

Long-term intake of cereal foods with differing postprandial insulin responses may be a factor that modulates the inflammatory status in individuals with the metabolic syndrome.

Low-carbohydrate, high-protein diets revisited

PURPOSE OF REVIEW

There has been continued interest in the physiological, nutritional and clinical aspects of low-carbohydrate diets. This review will discuss the effects on appetite regulation, metabolic parameters, body weight and body composition, the role of glycemic index and glycemic load, as well as long-term outcomes.

RECENT FINDINGS

Low-carbohydrate, high-protein diets appear to improve satiety through their actions on measures of adiposity and gut peptides that influence appetite and caloric intake. Specific macronutrients such as low glycemic index carbohydrates and dietary protein impact appetite, calorie intake and metabolic parameters independent of weight loss. Long-term data, however, continue to support that total weight loss among low-carbohydrate dieters is not significantly different from low-fat dieters. The long-term safety of low-carbohydrate, high-protein diets on cardiovascular disease risk remains undetermined.

SUMMARY

Low-carbohydrate, high-protein diets may be an effective choice for weight loss, enhanced satiety and improved metabolic parameters.

Treatment of childhood obesity

PURPOSE OF REVIEW

To provide an overview of treatments for childhood obesity, highlighting recent advances and recommendations.

RECENT FINDINGS

The three main treatment modalities are lifestyle interventions, medications, and bariatric surgery. Recent data support the short-term effectiveness of lifestyle interventions, and show that continued behavioral intervention increases the likelihood of a sustained effect for up to 2 years. New studies and regulatory decisions on medications for obesity (including orlistat, sibutramine, and metformin) are discussed. Emerging data suggest substantial weight loss after bariatric surgery in morbidly obese adolescents but also indicate adverse effects. An expert panel recently provided guidelines that alter definitions of obesity and offer a framework for obesity management. These guidelines are compared with others, and integrated recommendations presented.

SUMMARY

While primary prevention of childhood obesity is important, broadly effective methods to do so are not yet available. Given the large population of obese children and the risks they face, an emphasis on treatment is also critical. We suggest a staged approach, emphasizing early intervention and lifestyle changes. We also suggest limiting bariatric surgery to selected adolescents in Institutional Review Board-approved research studies. Health-policy interventions can facilitate both prevention and treatment of childhood obesity.

Complementary and alternative medicine therapies to promote healthy moods

Pediatric mood disorders (unipolar depression and bipolar disorder) are serious, common, persistent, and recurrent medical conditions. Depression is the second leading cause of illness and disability among young people worldwide. A healthy lifestyle and healthy environment are the cornerstones for promoting positive moods. In addition, several complementary therapies, including nutritional supplements, herbs, mind-body therapies, massage, and acupuncture can be helpful. The focus of this article is the fundamental lifestyle approaches and complementary therapies that enhance mental health in young people. Various resources are available to clinicians to help patients and families promote mental health.