Beneficial Effects of the Ketogenic Diet on Nonalcoholic Fatty Liver Disease (NAFLD/MAFLD)

The prevalence of nonalcoholic fatty liver disease (NAFLD) is likely to be approaching 38% of the world's population. It is predicted to become worse and is the main cause of morbidity and mortality due to hepatic pathologies. It is particularly worrying that NAFLD is increasingly diagnosed in children and is closely related, among other conditions, to insulin resistance and metabolic syndrome. Against this background is the concern that the awareness of patients with NAFLD is low; in one study, almost 96% of adult patients with NAFLD in the USA were not aware of their disease. Thus, studies on the therapeutic tools used to treat NAFLD are extremely important. One promising treatment is a well-formulated ketogenic diet (KD). The aim of this paper is to present a review of the available publications and the current state of knowledge of the effect of the KD on NAFLD. This paper includes characteristics of the key factors (from the point of view of NAFLD regression), on which ketogenic diet exerts its effects, i.e., reduction in insulin resistance and body weight, elimination of fructose and monosaccharides, limitation of the total carbohydrate intake, anti-inflammatory ketosis state, or modulation of gut microbiome and metabolome. In the context of the evidence for the effectiveness of the KD in the regression of NAFLD, this paper also suggests the important role of taking responsibility for one's own health through increasing self-monitoring and self-education.

A Mobile-Based Nutrition Tracker App Enhanced Dietitian-Guided 2:1:1 Diet-Induced Weight Loss: An 8-Week Retrospective Cohort Study in Taiwan

Effective weight management interventions involve a combination of behavioral strategies focusing on dietary changes. Tracing the change through mobile apps has been proven to be a valuable platform for facilitating weight management in many countries. However, the effectiveness of mobile app-based dietary intervention on weight management in Taiwan remains to be determined. By using the designated mobile app, this study aimed to assess the efficacy of the diet intervention, which is based on a 2:1:1 portion control plate and a flexible low-carbohydrate (FLC) diet. This 8-week retrospective cohort study involved 10,297 participants who were divided into two groups: the intervention group (joined an 8-week diet intervention program with the daily diet record assessed by registered dietitians) and the control group (voluntarily using the app without instructional materials or coaching). After eight weeks of intervention, the intervention group showed a higher weight loss percentage (-4.78% vs. -1.54%), body mass index (BMI) (-1.26 kg/m2 vs. 0.69 kg/m2), and diet record completeness (73.52% vs. 28.91%) compared with the control group. With respect to gender, male participants showed higher baseline weight and higher weight loss (-6.02%) in the intervention group. In the intervention group, 2871 participants (33.4%) lost less than 4% of their weight, 5071 participants (58.9%) lost 4-8% of their body weight, and 662 participants (7.7%) lost >8% of their weight. Compared to the low-effectiveness group (weight lost <4%), the high-effectiveness group (weight lost >8%) had a significantly higher diet record completeness (91.61 ± 15.99 vs. 55.81 ± 32.92), dietary compliance (green light %) (88.93 ± 9.9 vs. 77.75 ±17.5), protein intake % (26.34 ± 2.85 vs. 23.49 ± 3.56), and fat intake % (49.66 ± 6.36 vs. 44.05 ± 7.37). Most importantly, the high-effectiveness group had a lower carbohydrate intake % (24.1 ± 7.86 vs. 32.46 ± 9.61). The results remained significant after being stratified by gender. This study found that the use of online applications plus the intervention of dietitians is beneficial for short-term weight loss. The composition of nutrients and dietary compliance also significantly impacted weight loss.

The effects of carbohydrate-restricted diet on psychological outcomes: a systematic review of randomized controlled trials

CONTEXT

Carbohydrate-restricted diets are widely used as an effective treatment tool for many chronic diseases. The impact of these diets on physical health is well known, but their impact on psychological health is less well described in the scientific literature. This is an important aspect to focus on, especially if the diets are to be sustainable in the long term.

OBJECTIVE

The objective of this study was to systematically review the scientific literature describing the effect of carbohydrate-restricted diets and ketogenic diets on psychological outcomes, as observed in randomized controlled trials. Additionally, the potential synergistic effect of carbohydrate-restricted diets and exercise or social factors on these outcomes was researched.

DATA SOURCES

Five databases (Web of Science, PubMed, Scopus, ScienceDirect, and MEDLINE Complete) were searched without restriction of publication date.

DATA EXTRACTION

The first data extraction was made in October 2020 and the second in May 2022. Abstract screening was performed by 3 independent reviewers. The quality of studies was assessed using the Jadad scale.

DATA ANALYSIS

Sixteen randomized controlled studies were included in the analysis. Five studies focused on clinical populations, 9 on obese/overweight populations, and 2 on healthy populations; all studies examined adult people. Four psychological outcomes were identified (quality of life, mental health, mood, and fatigue), and they were examined in connection with a very low-carbohydrate or ketogenic diet.

CONCLUSION

Daily low-carbohydrate intake may not negatively affect psychological well-being, and low-carbohydrate diets and ketogenic diets are no worse than other diets in this respect. An intervention of 12 weeks or longer can bring benefits in psychological well-being. The synergistic effect of diet and exercise or social factors was not reviewed due to lack of evidence.

The Effectiveness of Nutritional Strategies in the Treatment and Management of Obesity: A Systematic Review

Obesity, a condition primarily resulting from positive energy balance, has become a significant global health concern. Numerous studies have demonstrated that obesity is a major risk factor for various illnesses, including different types of cancer, coronary heart disease, sleep apnea, CV stroke, type II diabetes mellitus, etc. To effectively address this issue, prevention and treatment approaches to manage body weight are crucial. There are several evidence-based approaches available for the treatment and management of obesity, taking into account factors such as body mass index classification, individual weight history, and existing comorbidities. To facilitate successful obesity treatment and management, there are pragmatic approaches and tools available, including the reduction of energy density, portion control, and diet quality enhancement. These approaches encompass the use of medications, lifestyle interventions, bariatric surgery, and formula diets. Regardless of the specific method employed, behavior change, reduction of energy intake, and increased energy expenditure are integral components for successful treatment and management of obesity. These measures allow patients to personalize and customize their dietary patterns, leading to effective and sustainable weight reduction. Incorporating physical activities and self-monitoring of individual diets are effective techniques for promoting behavior change in obesity and weight management. The main objective of this systematic review is to evaluate the effectiveness of dietary/nutritional interventions in the treatment and management of obesity through provision of valuable insights into the effectiveness of such nutritional strategies. To attain this, a comprehensive analysis of various dietary approaches and their impacts on weight will be conducted.

The Effects of Ketogenic Diet on Insulin Sensitivity and Weight Loss, Which Came First: The Chicken or the Egg?

The ketogenic diet (KD) is, nowadays, considered an interesting nutritional approach for weight loss and improvement in insulin resistance. Nevertheless, most of the studies available in the literature do not allow a clear distinction between its effects on insulin sensitivity per se, and the effects of weight loss induced by KDs on insulin sensitivity. In this review, we discuss the scientific evidence on the direct and weight loss mediated effects of KDs on glycemic status in humans, describing the KD's biochemical background and the underlying mechanisms.

Psychological Support Strategies for Adults With Type 2 Diabetes in a Very Low-Carbohydrate Web-Based Program: Randomized Controlled Trial

BACKGROUND

A very low-carbohydrate (VLC) nutritional strategy may improve glycemic control and weight loss in adults with type 2 diabetes (T2D). However, the supplementary behavioral strategies that might be able to improve outcomes using this nutritional strategy are uncertain.

OBJECTIVE

This study aims to compare the impact of adding 3 different supplementary behavioral strategies to a web-based VLC diet intervention. To our knowledge, this is the first trial to randomize participants to different frequencies of dietary self-monitoring.

METHODS

The study included 112 overweight adults with T2D (hemoglobin A1c ≥6.5%) taking no antiglycemic medications or only metformin. They received a remotely delivered 12-month VLC diet intervention. Participants were randomly assigned through a full factorial 2×2×2 design to supplementary strategies: either daily or monthly dietary self-monitoring, either mindful eating training or not, and either positive affect skills training or not. Our research goal was to determine whether 3 different supplemental strategies had at least a medium effect size (Cohen d=0.5).

RESULTS

Overall, the VLC intervention led to statistically significant improvements in glycemic control (-0.70%, 95% CI -1.04% to -0.35%; P<.001), weight loss (-6.82%, 95% CI -8.57% to -5.08%; P<.001), and depressive symptom severity (Cohen d -0.67, 95% CI -0.92 to -0.41; P<.001). Furthermore, 30% (25/83) of the participants taking metformin at baseline reduced or discontinued their metformin. Only 1 Cohen d point estimate reached 0.5; daily (vs monthly) dietary self-monitoring had a worse impact on depressive symptoms severity (Cohen d=0.47, 95% CI -0.02 to 0.95; P=.06). None of the strategies had a statistically significant effect on outcomes. For changes in our primary outcome, hemoglobin A1c, the daily (vs monthly) dietary self-monitoring impact was 0.42% (95% CI -0.28% to 1.12%); for mindful eating, it was -0.47% (95% CI -1.15% to 0.22%); and for positive affect, it was 0.12% (95% CI -0.57% to 0.82%). Other results for daily (vs monthly) dietary self-monitoring were mixed, suggesting an increase in weight (0.98%) and depressive symptoms (Cohen d=0.47), less intervention satisfaction (Cohen d=-0.20), more sessions viewed (3.02), and greater dietary adherence (Cohen d=0.24). For mindful eating, the results suggested a benefit for dietary adherence (Cohen d=0.24) and intervention satisfaction (Cohen d=0.30). For positive affect, the results suggested a benefit for depressive symptoms (Cohen d=-0.32), the number of sessions viewed (3.68), dietary adherence (Cohen d=0.16), and intervention satisfaction (Cohen d=0.25).

CONCLUSIONS

Overall, our results support the use of a VLC diet intervention in adults with T2D. The addition of monthly (not daily) dietary self-monitoring, mindful eating, and positive affect skills training did not show a definitive benefit, but it is worth further testing.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03037528; https://clinicaltrials.gov/ct2/show/NCT03037528.

The association between a low-carbohydrate diet score and the risk of diabetic nephropathy in women: A case-control study

OBJECTIVES

Because evidence linking carbohydrate consumption to diabetic nephropathy (DN) is scarce, and the association between a low-carbohydrate diet (LCD) and DN has not been investigated, we sought to investigate whether a higher LCD score is associated with DN among women.

METHODS

In a case-control study, 105 women with type 2 diabetes mellitus and DN and 105 controls with type 2 diabetes mellitus and without DN who attended Kowsar Diabetes Clinic in Semnan, Iran, were matched for age and diabetes duration. The data related to anthropometric and biochemical measures were collected and a food frequency questionnaire with 147 items was used to assess dietary intake. Based on the food frequency questionnaire, we calculated an LCD score for each study participant. Multivariate logistic regression was performed to examine the association between an LCD score and the odds of developing DN.

RESULTS

The results of the study demonstrated that the LCD score was not significantly associated with DN in the crude model (odds ratio = 0.39; 95% confidence interval, 0.14-1.07; P = 0.06). However, after adjusting for several confounders, subjects in the top quartile of the LCD score were associated with a 71% lower risk of DN (odds ratio [OR] = 0.29; 95% confidence interval, 0.10-0.86; P = 0.02). A significant trend toward decreased urinary albumin excretion was found with an increase in the LCD score (P = 0.005).

CONCLUSIONS

A diet low in carbohydrates was inversely associated with risk of DN. Further observational studies, and preferably randomized controlled trials, are needed to confirm the present results.

Prescribing diabetes nutrition therapy: a qualitative study of dietitians' experiences of carbohydrate restriction in Canada

BACKGROUND

Diabetes care has traditionally not included nutrition therapy using carbohydrate restriction, nor has carbohydrate restriction been taught to registered dietitians (RDs) to support patients living with diabetes choosing this dietary approach. We aimed to describe the experiences and views of RDs caring for patients using therapeutic carbohydrate-restricted diets (TCR), particularly metabolic conditions such as type 2 diabetes or prediabetes.

SUBJECTS/METHODS

A qualitative study design using free-text responses from an online needs assessment survey was employed. RDs who practised in Canada were invited (n=6640) and 274 completed the survey, with 45 respondents who regularly prescribed TCR to their patients providing open-text responses (2987 words), which were analysed using inductive thematic analysis.

RESULTS

We identified four themes characterising Canadian RDs' experiences around prescribing TCR: interpersonal context, personal experience/knowledge, regulatory environment and patient-centredness. While these themes often interacted, each impacted TCR prescription uniquely, with patient-centred care at the core of reported experiences of prescribing.

CONCLUSIONS

There exists a variety of experiences and perspectives related to prescribing of TCR among Canadian RDs caring for patients with diabetes, and all focus on the patient's needs, benefits and preferences. Prescribing TCR was often informed by the scientific literature yet also by RDs' experiential knowledge. Responses highlighted a desire for evidence-based educational materials and greater discussion within the diabetes nutrition community on this topic.

A bibliometric and visual analysis of low carbohydrate diet

Introduction

Numerous studies have confirmed the effects of low carbohydrate diet (LChD) on metabolism and chronic diseases. However, there were no bibliometric studies on LChD. This study was conducted through a bibliometric analysis to investigate the current status, hotspots and frontiers trends.

Methods

We searched all research publications related to LChD from 2002 to 2021 on the Web of Scientific Core Collection (WoSCC). CiteSpace and VOSviewer software was used to analyze countries/regions, institutions, journals, authors, references, and keywords.

Results

A total of 6938 papers were included, with an increasing trend of annual publication. LChD categories mainly included nutrition, endocrinology, and neurosciences which reflected the interdisciplinary characteristics. USA was with the largest number and the world science center in LChD field. Universities were main research institutions and five of the top 10 institutions were from USA. Eric Heath Kossoff had 101 publications and ranked first. Nutrients was the leading journal. "A randomized trial of a low-carbohydrate diet for obesity" and "Obesity" were considered to be the most co-cited and cited reference respectively. The hotspots of LChD are four aspects, "ketogenic diet", "metabolism disease", "cardiovascular disease" and "cancer". We summarized that "oxidative stress", "gut microbiota", and "inflammation factors" are becoming frontiers trends of LChD research in the future and deserve further study.

Discussion

Over the past 20 years research on LChD has gained great attention. To better explore LChD field, multilevel mechanism studies will be required in the future.

Revised Protein Sparing Diet in Obesity and Type 2 Diabetes Mellitus

Effective nutrition therapy is a pressing issue in obesity and type 2 diabetes mellitus (T2DM) management. As such, this research aimed to determine the performance of a revised dietary strategy built on the protein-sparing diet in obesity and type 2 diabetes mellitus with regard to obtaining a rapid and stable improvement in glucometabolic control, body weight, body composition, and energy metabolism when applying the strategy in just twenty-one days. The revised protein-sparing diet differs from the traditional protein-sparing modified fast (PSMF) because it does not include foods. The daily calorie intake of this diet is exclusively derived from Isolate whey protein in addition to a formulation of Isolate whey protein enriched with essential amino acids in free form, with the addition of lipids such as extra virgin olive oil and coconut oil as a source of medium chain fatty acids, where the latter is taken for only the first four days of the diet, together with the use, for the same duration, of extended-release metformin, as the only antihyperglycemic allowed. Anthropometric measurements, bioimpedance analysis, indirect calorimetry, and blood chemistry assessments were conducted at the beginning of the study, time 0 (T0), and at the end, time 1 (T1), i.e., on the 21st day. The main outcomes of the revised protein-sparing diet after only twenty-one days were a reduction in body weight with the predominant loss of visceral atherogenic abdominal fat and, therefore, a possible contextual reduction in ectopic fat deposits together with a simultaneous reduction in insulin resistance and normalization of insulin levels, maintenance of free fat mass and basal metabolism, restoration of metabolic flexibility, and improvement of the glucometabolic and lipidic parameters. These results demonstrate the promising potential of the revised protein-sparing diet as an "etiologic tool" in the integrated nutritional treatment of metabolic diseases such as obesity and type 2 diabetes mellitus.

The association of Carbohydrate Quality Index with cardiovascular disease risk factors among women with overweight and obesity: A cross-sectional study

Purpose

Diet is one of the most important factors influencing cardiovascular disease (CVD). The negative relationship between carbohydrate intake with lipid profiles and body weight has been previously investigated. However, this is the first study seeking to assess the association of carbohydrate quality index (CQI) with CVD risk factors.

Methods

This cross-sectional study was conducted on 291 Iranian overweight and obese women, with a body mass index (BMI) ranging between 25 and 40 kg/m², and aged 18–48 years. CQI scores were calculated by using a validated 168-item semi-quantitative food frequency questionnaire (FFQ). Biochemical and anthropometric measures were assessed using standard methods, and bioelectrical impedance was used to measure body composition.

Results

We observed that fruits (P < 0.001), vegetables (P < 0.001), and protein (P = 0.002) intake were higher in participants with a higher score of the CQI. When we adjusted for potential confounders, we observed that the CQI was negatively related to systolic blood pressure (SBP) (β = −6.10; 95% CI = −10.11, −2.10; P = 0.003) and DBP (β = −3.11; 95% CI = −6.15, −0.08; P = 0.04). Also, greater adherence to a high CQI dietary pattern, compared to the reference group, was negatively related to HOMA-IR (β = −0.53; 95% CI = −0.94, −0.12) (P for trend = 0.01), WC (β = −3.18; 95% CI = −6.26, −0.10) (P for trend = 0.04), BMI (β = −1.21; 95% CI = −2.50, 0.07) (P for trend = 0.06), and BF (β = −2.06; 95% CI = −3.82, −0.30) (P for trend = 0.02).

Conclusion

In line with previous studies, the CQI was inversely associated with blood pressure, WC, BMI, and BF. Further prospective and clinical trial studies are suggested to confirm these data.

Low-carbohydrate diet score is associated with improved blood pressure and cardio-metabolic risk factors among obese adults

Obesity is associated with numerous co-morbidities and diet, is one of the modifiable risk factors for prevention against these obesity-related metabolic disorders. In the current study, we aimed to evaluate the association between adherence to low carbohydrate diet (LCD) score and serum lipids, glycemic markers, blood pressure, and anthropometric parameters among obese individuals. The current cross-sectional study is a combination of two projects with total participants of 359 obese individuals (body mass index [BMI] ≥ 30 kg/m2 ) aged 20-50 years were included. Dietary intake was assessed by a validated semi-quantitative food frequency questionnaire (FFQ) of 132 food items. Low carbohydrate diet score was estimated by deciles of dietary intakes. Metabolic syndrome (MetS) was defined based on the guidelines of the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III). Enzymatic methods were used to assess serum lipids, glucose, and insulin concentrations. Blood pressure was measured by sphygmomanometer and body composition with bioelectrical impedance analysis (BIA). Higher adherence to LCD score was associated with significantly lower DBP and triglyceride (TG) concentrations and increased high density lipoprotein (HDL)-C levels after adjustment for the confounders (p < 0.05). A non-significant reduction in systolic blood pressure (SBP) and total cholesterol (TC) values were also observed. Also, high adherence to LCD score was associated with reduced prevalence of metabolic syndrome (p < 0.05). Higher BMI, fat mass, and lower fat-free mass were also accompanied with higher adherence to LCD score. According to our study, low carbohydrate diet score was associated with more favorable cardio-metabolic risk factors independent of some confounders like age, BMI, sex, and physical activity level. Further studies in different communities will help for generalization of our findings.

A prospective study of carbohydrate intake and risk of all-cause and specific-cause mortality

PURPOSE

To investigate the associations between carbohydrate intake and the risk of overall and specific-cause mortality in a prospective cohort study.

METHODS

Diet was measured using 24 h dietary recalls. Underlying cause of death was identified through linkage to the National Death Index. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression.

RESULTS

During a median follow-up of 7.1 years among 35,692 participants who aged 20-85 years, a total of 3854 deaths [783 cardiovascular disease (CVD)-specific and 884 cancer-specific death] were identified. Carbohydrate intake was not associated with risk of overall mortality (multivariable-adjusted HR comparing extreme quartiles 1.03, 95% CI 0.94, 1.13, p_trend = 0.799), while higher fiber intake was associated with lower mortality risk (HR 0.86, 95% CI 0.77, 0.95, p_trend = 0.004). Replacing 5% of energy from carbohydrate with both plant fat and plant protein was associated with 13% (95% CI 8%, 17%) and 13% (95% CI 3%, 22%) lower risk of total and CVD mortality, respectively. Whereas a positive or null association was found when replacing carbohydrate with both animal fat and animal protein. Higher carbohydrate-to-fiber ratio was associated with increased risk of overall (HR 1.20, 95% CI 1.09, 1.33, p_trend < 0.001) and cancer-specific (HR 1.17, 95% CI 0.95, 1.44, p_trend = 0.031) mortality.

CONCLUSIONS

Our findings suggested that high fiber diet or diet with low carbohydrate-to-fiber ratio was associated with lower long-term death risk, and provided evidence for the health benefit from dietary substitution of both plant fat and plant protein for carbohydrate.

Challenges to dietary hypertension self-management as described by a sample of African American older adults

BACKGROUND

Hypertension rates are disproportionately higher among Black or African Americans (Black/African American) compared to other racial and ethnic groups in the United States. However, research on self-management strategies to control hypertension through healthy eating such as the Dietary Approaches to Stop Hypertension (DASH), and ketogenic diets has underexplored the use of dietary strategies among older Black/African American adults. In reporting contemporary challenges with implementing dietary strategies targeting blood pressure control among Black/African American older adults living with hypertension, this study addresses a clear need.

AIMS

Prior research has only partially addressed the challenges older Black/African Americans face in implementing and maintaining dietary strategies to control hypertension, therefore the current study aimed to address this gap by reporting contemporary challenges, as reported by a sample of Black/African American older adults living with hypertension.

METHODS

Nineteen Black/African American older adults living with hypertension participated in a focus group. An interview guide with open-ended questions on dietary approaches to self-management hypertension was used to guide data collection. Responses were audio-recorded, transcribed verbatim, and interpreted using qualitative thematic analysis.

RESULTS

Study participants were 71.6 years (SD = 8.3), 87.1% were women, and all were self-identified as Black/African American. Overall, participants shared that they were interested in improving their hypertension self-management skills. They expressed uncertainty about dietary strategies related in part to a lack of knowledge about incorporating or excluding certain foods and adhering to complex dietary recommendations. Participants also related financial concerns about accessing the recommended foods to control hypertension and expressed confusion about how to manage hypertension alongside other comorbidities.

LINKING EVIDENCE TO ACTION

This study highlights several barriers that Black/African American older adults face (lack of dietary knowledge, lack of financial resources, and unique barriers to managing multiple comorbid health conditions), which often pose simultaneous and intersecting barriers to managing hypertension using existing evidence-based dietary strategies.

Impact of an online multicomponent very-low-carbohydrate program in women with polycystic ovary syndrome: a pilot study

OBJECTIVE

To study the impact of a very-low-carbohydrate (VLC) diet for 16 weeks in overweight or obese women with polycystic ovary syndrome (PCOS).

DESIGN

Single-arm prospective pilot study.

SETTING

We recruited participants using medical records from an academic medical center.

PATIENTS

Twenty-nine overweight or obese women (body mass index, 25-50 kg/m2) with PCOS.

INTERVENTIONS

We taught participants to follow a VLC diet and provided information about a variety of behavioral skills including mindfulness and positive affect using an online 16-week intervention.

MAIN OUTCOME MEASURES

Changes in body weight, glycated hemoglobin, and PCOS-related quality of life.

RESULTS

The intervention led to positive health outcomes including decreases in percent weight (mean difference = -7.67, SD = 6.10) and glycated hemoglobin level (mean difference = -0.21%, SD = 0.27), an increase in sex hormone binding globulin level (mean difference = 9.24 nmol/L, SD = 16.34), and increases in PCOS-related quality of life measures, including menstrual predictability (mean difference = 2.10, SD = 2.76) and body hair (mean difference = 1.14, SD = 1.04). The low-density lipoprotein cholesterol level increased (mean difference = 0.23 mmol/L, SD = 0.49).

CONCLUSIONS

The results suggest that a VLC dietary intervention has potential to promote both weight loss and glycemic control in overweight and obese adults with PCOS, two key components in the prevention of type 2 diabetes.

TRIAL REGISTRATION NUMBER

NCT03987854.

The association between low-carbohydrate diet score and metabolic syndrome among Iranian adults

OBJECTIVE

Assessing the relationship between low-carbohydrate diet (LCD) score and metabolic syndrome (Mets) in Iranian adults.

DESIGN

Cross-sectional study.

SETTING

Yazd Health Study and Taghzieh Mardom-e-Yazd study.

PARTICIPANTS

Data of 2074 participants were used. Dietary intakes were assessed by a validated semi-quantitative FFQ. LCD score was calculated for each person by summing up the assigned scores to deciles of energy percentages from macronutrients. Mets was evaluated using National Cholesterol Education Program Adult Treatment Panel III. Eventually, association between LCD score and Mets was examined using logistic regression.

RESULTS

Total Mets prevalence was approximately 40·5 %. After adjustment for confounders, subjects in the higher quartile of LCD score had a significant lower chance of Mets than lower quartile among all participants (Q4 v. Q1: OR: 0·68, 95 % CI (0·50, 0·92)) and separately in men (Q4 v. Q1: OR: 0·54, 95 % CI (0·34, 0·86)) and women (Q2 v. Q1: OR: 0·53, 95 % CI (0·34, 0·82)). Furthermore, more LCD adherence in men reduced abdominal obesity by 47 % (Q3 v. Q1: OR: 0·53, 95 % CI (0·28, 0·99)). A significant inverse relation was also observed between low HDL cholesterol and LCD score in all participants (Q4 versus Q1 OR: 0·74, 95% CI: 0·56-0·99) and separately in men (Q4 versus Q1 OR: 0·63, 95% CI: 0·40-0·98).

CONCLUSIONS

More adherence to LCD might be related to lower chance of Mets and some of its components such as low HDL-cholesterol and abdominal obesity specially in men. Further studies are required to confirm the findings.

The Relationship between Modern Fad Diets and Kidney Stone Disease: A Systematic Review of Literature

OBJECTIVES

Kidney stone disease (KSD) has a strong association with diet metabolic syndrome. This review aims at exploring the lithogenic risk posed by the current most popular diets. Our approach was to search for the effect of each diet type on the major urinary risk factors, to try to draw conclusions regarding the association of a specific diet type and KSD.

METHODS

This systematic review searched for the available literature exploring the association between the existing popular fad diets and KSD. Articles in English, French and Spanish were included, without restriction of the search period with the final search done in August 2021.

RESULTS

Total number of studies and studies for each diet type was as follows: 22 articles for the low carbohydrate diet, 20 articles for high protein diets, 26 articles for vegetarian and vegan diets. There exists a substantial variability in different low carbohydrate and high protein diets, and considerable overlap between modern popular fad diets. High carbohydrate intake might increase urine uric acid, calcium and oxalate levels. High protein diets increase urine calcium and uric acid and lower urine pH and citrate. Consumption of fruits and vegetables increases the urinary volume and urinary citrate. In vegan diets, sufficient daily calcium intake is important to avoid possible secondary hyperoxaluria.

CONCLUSIONS

Few studies evaluated the direct relationship between modern fad diets and KSD. In general, the reduction of carbohydrate in the diet, and counterbalancing protein rich diets with sufficient intake of fruits and vegetables, seem to play a protective role against KSD formation. Maintaining sufficient calcium intake in vegan and vegetarian diets is important. Additional research is needed to directly evaluate the link between KSD and each diet type.

[The ketogenic diet: history, mechanism of action, indications and contraindications]

Low-carb diets have been successfully used to alleviate a number of severe neurological diseases for about 100 years. The publication of the results of new studies suggesting that this type of diet may play a therapeutic role in other pathologies such as diabetes, obesity, polycystic ovary syndrome, and oncology is of particular interest for both doctors and the public. However, the long-term safety of using a low-carb or ketogenic diet, as well as its impact, primarily on the risks of developing cardiovascular diseases, remains poorly studied. This article presents the results of observation of patients against the background of a low-carbohydrate diet, both in the short-term perspective as well as provides an assessment of its long-term consequences.

Clinical Use of a Real-World Low Carbohydrate Diet Resulting in Reduction of Insulin Dose, Hemoglobin A1c, and Weight

Introduction: Type 2 Diabetes Mellitus (T2DM) is increasing in epidemic proportions. In addition to the morbidity and mortality, for those treated with insulin, the physical, psychological, and financial tolls are often greater. Our real-world study evaluated a Low Carbohydrate Diet (LCD) in patients with T2DM on insulin with respect to glycemic control, insulin reduction, and weight loss. Materials and Methods: A prospective cohort study was conducted via an Electronic Medical Record search for patients attending the Virginia Commonwealth University Medical Weight Loss Program from 2014 to 2020 with Type 2 Diabetes Mellitus who initially presented on insulin. Data was extracted for 1 year after enrollment. The weight loss program focuses on a LCD. Results: Of 185 participants, the mean (± SD) age was 56.1 (9.9) years. Seventy percent were female and 63% were black. Eighty-five completed 12 months (45.9%), reduced their median (25-75% interquartile range, IQR) insulin dose from 69 to 0 units (0-18, p < 0.0001), HbA1c from 8 to 6.9% (6.2-7.8, p < 0.0001), and weight from 116 to 99 kg (85-120, p < 001). Eighty six percent who completed 12 months were able to reduce or discontinue insulin, with 70.6% completely discontinuing. Among all participants who completed 3, 6, or 12 months, 97.6% were able to reduce or eliminate insulin use. Conclusion: In patients with T2DM on a LCD, it is possible to reduce and even discontinue insulin use while facilitating weight loss and achieving glycemic control. A Low Carbohydrate Diet should be offered to all patients with diabetes, especially those using insulin.

2020 Korean Society for the Study of Obesity Guidelines for the Management of Obesity in Korea

Obesity is a prevalent and complex disease. The prevalence of obesity in Korea increased from 29.7% in 2010 to 35.7% in 2018, with the prevalence of abdominal obesity being 23.8% in 2018. Obesity contributes to medical costs and socioeconomic burden due to associated comorbidities. The treatment and management of obesity is changing based on new clinical evidence. The 2020 Korean Society for the Study of Obesity Guideline for the Management of Obesity in Korea summarizes evidence-based recommendations and treatment guidelines.

Supporting people to implement a reduced carbohydrate diet: a qualitative study in family practice

INTRODUCTION

Much of the science behind dietary guidelines for risk reduction and chronic disease management is equivocal, and there are well-accepted uncertainties and complexities relating to diet in everyday life, as well as physiological processes. Guidelines have therefore stopped short of aligning with one particular approach, instead highlighting several evidence-based options. However, reduced carbohydrate, or 'low-carb', diets have increasing traction in the media and with patients, practitioners and the general public. This qualitative study examines healthcare practitioner (HCP) experiences of implementing a reduced carbohydrate diet.

METHODS

Semistructured, qualitative interviews were conducted with 19 HCPs in the UK family practice (including general practitioners, practice nurses and non-medical practitioners), recruited through a special interest forum, and social media. Data analysis employed social science theory and methods to produce key themes.

RESULTS

All participants self-identified as 'low-carb practitioners' who, over time, had introduced a specific focus around carbohydrate reduction into their work. They reported transformations in patients' metabolic markers, patient enthusiasm for the approach and renewed job satisfaction. Key themes highlight experiences of: (1) discovering low-carb as a new 'tool-in-the-box'; (2) promoting and supporting incremental low-carb experimentation; and (3) diverging from established dietary guidelines.

CONCLUSIONS

This study provides important experience-based evidence on a topical dietary intervention. Participants strongly advocated for the use of low-carb diets. The successes described draw attention to the need for pragmatic, formative evaluation of low-carb advice and support as a 'complex intervention' (alongside physiological research), to justify, challenge and/or shape low-carb intervention in clinical practice. The findings raise important questions about the contribution of particular care practices to the apparent success of low-carb. Social science analyses can elucidate how dietary intervention is carried out across different healthcare settings (eg, dietetics, endocrinology) and patient groups, how healthcare practices intersect with people's everyday self-management and how different forms of evidence are invoked and prioritised.

Adherence to Ketogenic and Mediterranean Study Diets in a Crossover Trial: The Keto-Med Randomized Trial

Adherence is a critical factor to consider when interpreting study results from randomized clinical trials (RCTs) comparing one diet to another, but it is frequently not reported by researchers. The purpose of this secondary analysis of the Keto-Med randomized trial was to provide a detailed examination and comparison of the adherence to the two study diets (Well Formulated Ketogenic Diet (WFKD) and Mediterranean Plus (Med-Plus)) under the two conditions: all food being provided (delivered) and all food being obtained by individual participants (self-provided). Diet was assessed at six time points including baseline (×1), week 4 of each phase when participants were receiving food deliveries (×2), week 12 of each phase when participants were preparing and providing food on their own (×2), and 12 weeks after participants completed both diet phases and were free to choose their own diet pattern (×1). The adherence scores for WFKD and Med-Plus were developed specifically for this study. Average adherence to the two diet patterns was very similar during both on-study time points of the intervention. Throughout the study, a wide range of adherence was observed among participants-for both diet types and during both the delivery phase and self-provided phase. Insight from this assessment of adherence may aid other researchers when answering the important question of how to improve behavioral adherence during dietary trials. This study is registered at clinicaltrials.gov NCT03810378.

The relation between low carbohydrate diet score and psychological disorders among Iranian adults

BACKGROUND

Since evidence regarding to low carbohydrate diet (LCD) and psychiatric disorders is little and controversial, this study aimed to assess relation between LCD score and psychological disorders including depression, anxiety, and stress among a large representative sample of Iranian adult population in Yazd city, Iran.

METHODS

This cross-sectional analysis was conducted on data of 7165 persons who participated in the recruitment phase of Yazd Health Study (YaHS) and Taghzieh Mardom-e-Yazd (TAMIZ) study. Dietary intakes were evaluated by a validated semi-quantitative food frequency questionnaire. LCD score was calculated for each person according to summing up assigned scores to deciles of percentages of energy from macronutrients. Assessment of psychological disorders was also conducted by the validated Iranian version of depression, anxiety and stress scale questionnaire (DASS 21). Eventually, association between adherence to LCD and psychological disorders was evaluated via logistic regression.

RESULTS

After adjusting the confounders, women in the third quartile of LCD score might had 38% lower chance of depression versus those in the first quartile (odds ratio (OR) = 0.62, confidence interval (CI) = 0.42-0.93). However, no significant relationship was observed for other psychological disorders.

CONCLUSIONS

More adherences to LCD might be associated with lower chance of depression only among women. Further studies special prospective studies are required to validate these results.

Physiopathology of Lifestyle Interventions in Non-Alcoholic Fatty Liver Disease (NAFLD)

Non-alcoholic fatty liver disease (NAFLD) is a major health problem, and its prevalence has increased in recent years. Diet and exercise interventions are the first-line treatment options, with weight loss via a hypocaloric diet being the most important therapeutic target in NAFLD. However, most NAFLD patients are not able to achieve such weight loss. Therefore, the requisite is the investigation of other effective therapeutic approaches. This review summarizes research on understanding complex pathophysiology underlying dietary approaches and exercise interventions with the potential to prevent and treat NAFLD.

An Almond-Based Low Carbohydrate Diet Improves Depression and Glycometabolism in Patients with Type 2 Diabetes through Modulating Gut Microbiota and GLP-1: A Randomized Controlled Trial

Background: Alow carbohydrate diet (LCD) is more beneficial for the glycometabolism in type 2 diabetes (T2DM) and may be effective in reducing depression. Almond, which is a common nut, has been shown to effectively improve hyperglycemia and depression symptoms. This study aimed to determine the effect of an almond-based LCD (a-LCD) on depression and glycometabolism, as well as gut microbiota and fasting glucagon-like peptide 1 (GLP-1) in patients with T2DM. Methods: This was a randomized controlled trial which compared an a-LCD with a low-fat diet (LFD). Forty-five participants with T2DM at a diabetes club and the Endocrine Division of the First and Second Affiliated Hospital of Soochow University between December 2018 to December 2019 completed each dietary intervention for 3 months, including 22 in the a-LCD group and 23 in the LFD group. The indicators for depression and biochemical indicators including glycosylated hemoglobin (HbA1c), gut microbiota, and GLP-1 concentration were assessed at the baseline and third month and compared between the two groups. Results: A-LCD significantly improved depression and HbA1c (p < 0.01). Meanwhile, a-LCD significantly increased the short chain fatty acid (SCFAs)-producing bacteria Roseburia, Ruminococcus and Eubacterium. The GLP-1 concentration in the a-LCD group was higher than that in the LFD group (p < 0.05). Conclusions: A-LCD could exert a beneficial effect on depression and glycometabolism in patients with T2DM. We speculate that the role of a-LCD in improving depression in patients with T2DM may be associated with it stimulating the growth of SCFAs-producing bacteria, increasing SCFAs production and GPR43 activation, and further maintaining GLP-1 secretion. In future studies, the SCFAs and GPR43 activation should be further examined.

Low carbohydrate diet and all cause and cause-specific mortality

BACKGROUND

Evidence is limited regarding the association between low-carbohydrate diet (LCD) score and mortality among Asians, a population that consumes a large amount of carbohydrates.

OBJECTIVE

The present study examined the association between low-carbohydrate diet (LCD) score (based on percentage of energy as carbohydrate, fat, and protein) and the risk of total and cause-specific mortality among Asians.

DESIGN

This study was a prospective cohort study in Japan with follow-up for a median of 16.9 years involving 43008 men and 50646 women aged 45-75 years. Association of LCD score, LCD score based on animal sources of protein and fat, and LCD score based on plant sources of protein and fat with risk of mortality was assessed using Cox proportional hazards model.

RESULTS

A U-shaped association was observed between LCD score and total mortality: the multivariable-adjusted hazard ratios (HRs) (95% CI) of total mortality for lowest through highest scores were 1.00, 0.95 (0.91, 1.01), 0.93 (0.88, 0.98), 0.93 (0.88, 0.98), and 1.01 (0.95, 1.07) (P-non-linearity <0.01). A similar association was found for mortality from cardiovascular disease (CVD) and heart disease. LCD score based on carbohydrate, animal protein, and animal fat also showed a U-shaped association for total mortality (P-non-linearity <0.01). In contrast, LCD score based on carbohydrate, plant protein, and plant fat was linearly associated with lower total (HR, 0.89; 95% CI: 0.83, 0.94 for highest versus lowest quintile), CVD [0.82 (0.73, 0.92)], heart disease [0.83 (0.71, 0.98)], and cerebrovascular disease [0.75 (0.62, 0.91) mortality.

CONCLUSIONS

Both LCD with high animal protein and fat and high-carbohydrate diet with low animal protein and fat were associated with higher risk of mortality. Meanwhile, LCD high in plant-based sources of protein and fat was associated with a lower risk of total and CVD mortality.

Low carbohydrate diet score and odds of neuromyelitis optica spectrum disorder: A case-control study

Introduction: Neuromyelitis optica spectrum disorder (NMOSD) is a demyelinating inflammatory disease of The Central nervous system. We aimed to investigate the association between low carbohydrate diet (LCD) and NMOSD odds. Method: Seventy NMOSD patients with definite diagnosis and 164 hospital-based controls were enrolled in this case-control study. Dietary data was obtained using a validated 168-item food frequency questionnaire. To determine the LCD score, participants were stratified into 11 groups according to carbohydrate, protein, fat, animal fat, animal protein, vegetable fat and vegetable protein intakes. Higher intake of protein and fat, and lower intake of carbohydrate received a higher score between 0-10. Macronutrients scores were summed together and LCD scores calculated. The association between LCD scores and likelihood of being assigned to NMOSD group was investigated using multiple regression models. Results: Total LCD scores increased from the median of 21.00 in the first decile to 53.00 in the tenth decile of LCD score. After adjustment for confounding factors including age, gender, BMI, energy intake, cigarette smoking and alcohol consumption, an inverse association was detected between LCD scores and odds of NMOSD. The odds of suffering from NMOSD declined significantly about 78% (OR: 0.22; 95% CI: 0.05-0.87) and 76% (OR: 0.24; 95% CI: 0.06-0.93) in the fifth and sixth deciles of LCD score compared to the first decile. Conclusion: From the obtained results it can be speculated that higher carbohydrate and lower protein and fat intakes may be associate with the increased odds of NMOSD. However, further studies are needed to confirm these results.

Induction of ketosis as a potential therapeutic option to limit hyperglycemia and prevent cytokine storm in COVID-19

The severe form of coronavirus disease 19 (COVID-19) is characterized by cytokine storm syndrome (CSS) and disseminated intravascular coagulation (DIC). Diabetes, obesity, and hypertension have, as minor common denominators, chronic low-grade inflammation and high plasma myeloperoxidase levels, which could be linked to pulmonary phagocytic hyperactivation and CSS. The hyperactivation of M1 macrophages with a proinflammatory phenotype, which is linked to aerobic glycolysis, leads to the recruitment of monocytes, neutrophils, and platelets from circulating blood and plays a crucial role in thrombo-inflammation (as recently demonstrated in COVID-19) through the formation of neutrophil extracellular traps and monocyte-platelet aggregates, which could be responsible for DIC. The modulation of glucose availability for activated M1 macrophages by means of a eucaloric ketogenic diet (EKD) could represent a possible metabolic tool for reducing adenosine triphosphate production from aerobic glycolysis in the M1 macrophage phenotype during the exudative phase. This approach could reduce the overproduction of cytokines and, consequently, the accumulation of neutrophils, monocytes, and platelets from the blood. Second, an EKD could be advantageous for the metabolism of anti-inflammatory M2 macrophages because these cells predominantly express oxidative phosphorylation enzymes and are best fed by the oxidation of fatty acids in the mitochondria. An EKD could guarantee the availability of free fatty acids, which are an optimal fuel supply for these cells. Third, an EKD, which could reduce high lactate formation by macrophages due to glycolysis, could favor the production of interferon type I, which are inhibited by excessive lactate production. From a practical point of view, the hypothesis, in addition to being proven in clinical studies, must obviously take into account the contraindications of an EKD, particularly type 1 or 2 diabetes treated with drugs that can cause hypoglycemia, to avoid the risk for side effects of the diet.

Beneficial effects of the ketogenic diet on nonalcoholic fatty liver disease: A comprehensive review of the literature

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease, characterized by hepatic fat accumulation and possible development of inflammation, fibrosis, and cancer. The ketogenic diet (KD), with its drastic carbohydrate reduction, is a now popular weight loss intervention, despite safety concerns on a possible association with fatty liver. However, KDs were also reported to be beneficial on hepatic pathology, with ketone bodies recently proposed as effective modulators of inflammation and fibrosis. If the beneficial impact of weight loss on NAFLD is established, less is known on the effect of macronutrient distribution on such outcome. In a hypocaloric regimen, the latter seems not to be crucial, whereas at higher calorie intake, macronutrient ratio and, theoretically, ketosis, may become important. KDs could positively impact NAFLD for their very low carbohydrate content, and whether ketosis plays an additional role is unknown. Indeed, several mechanisms may directly link ketosis and NAFLD improvement, and elucidating these aspects would pave the way for new therapeutic strategies. We herein aimed at providing an accurate revision of current literature on KDs and NAFLD, focusing on clinical evidence, metabolic pathways involved, and strict categorization of dietary interventions.

Low-carbohydrate interventions for adolescent obesity: Nutritional adequacy and guidance for clinical practice

Low-carbohydrate dietary patterns are re-emerging as a popular method of weight reduction. However, their nutritional adequacy to meet the needs of growing adolescents should be considered. This study aimed to design theoretical low-carbohydrate meal plans for clinical use in the management of adolescent obesity and assess nutritional adequacy. Meal plans were created for three levels of carbohydrate restriction (≤30, ≤50 and ≤120 g/day) without energy, protein or total fat restriction. Nutrient analysis was conducted using the FoodWorks Australia Ltd software (databases: AUSNUT 2013, AusBrands 2017, AusFoods 2017, NUTTAB 2010, New Zealand FOODfiles 2016), and compared with Australian Nutrient Reference Values for male and female adolescents aged 14 to 18 years. All low-carbohydrate meal plans met the Recommended Dietary Intake, Adequate Intake or Estimated Average Requirements for most micronutrients at an energy intake of 6.3 to 7.2 MJ/day (1510-1730 kcal/day). The proportion of energy from saturated fat exceeded recommendations across all models (11.3%-17.1%). Dietary manipulation was required to minimize saturated fat and reach micronutrient adequacy, particularly for calcium in males and females, and iron for females. In practice, this may be challenging considering individual lifestyle and preferences. Therefore, the use of low-carbohydrate diets with adolescents should be monitored by a trained professional to ensure nutritional adequacy.

Association of low-carbohydrate diet score with overweight, obesity and cardiovascular disease risk factors: a cross-sectional study in Iranian women

Introduction: This study aimed to determine the association of low-carbohydrate-diet score with overweight, obesity and cardiovascular risk factors among Iranian women. Methods: In healthy Iranian women 20-50 years, demographics, anthropometrics, physical activity, blood pressure, fasting blood glucose, blood lipids, and dietary intake (using a validated food frequency questionnaire) were assessed. Participants were divided into deciles of macronutrient intakes. Women in the lowest decile of carbohydrate intake received a score of 9 and women in the highest decile received a score of 0. For protein and fat intakes, women in the lowest decile received a score of 0 for that macronutrient and those in the highest decile received the score of 9. Macronutrient scores were summed to create the low-carbohydrate diet score and women were grouped into tertiles based on these scores. Continuous and qualitative variables were compared among the low-carbohydrate-diet score by one-way ANOVA and chi-square test, respectively. Logistic regression was used to determine the association of low-carbohydrate-diet score and cardiovascular risk factors. Results: A total of 209 women were included in the study. Socioeconomic status significantly increased from tertile 1 to 3 of the low-carbohydrate diet score (P = 0.02). Total dietary glycemic index (GI) significantly differed among tertiles (tertile 1 GI: 63.1 ±0.50, tertile 2 GI: 61.9 ± 0.5, tertile 3 GI: 59.5 ± 0.5; P < 0.001). The odds ratios for overweight, obesity and cardiovascular risk factors were not significantly different among the tertiles of low-carbohydrate diet score. Conclusion: In Iranian women, diets lower in carbohydrate and higher in protein and fat were not associated with overweight, obesity and cardiovascular risk factors.

Employing proteomics to understand the effects of nutritional intervention in cancer treatment

Lifestyle optimizations are implementable changes that can have an impact on health and disease. Nutrition is a lifestyle optimization that has been shown to be of great importance in cancer initiation, progression, and metastasis. Dozens of clinical trials are currently in progress that focus on the nutritional modifications that cancer patients can make prior to and during medical care that increase the efficacy of treatment. In this review, we discuss various nutritional inventions for cancer patients and the analytical approaches to characterize the downstream molecular effects. We first begin by briefly explaining the many different forms of nutritional intervention currently being used in cancer treatment as well as their motivating biology. The forms of nutrient modulation described in this review include calorie restriction, the different practices of fasting, and carbohydrate restriction. The review then shifts to explain how proteomics is used to determine biomarkers of cancer and how it can be utilized in the future to determine the metabolic phenotype of a tumor, and inform physicians if nutritional intervention should be recommended for a cancer patient. Nutrigenomics aims to understand the relationship of nutrients and gene expression and can be used to understand the downstream molecular effects of nutrition restriction, partially through proteomic analysis. Proteomics is just beginning to be used as cancer diagnostic and predictive tools. However, these approaches have not been used to their full potential to understand nutritional intervention in cancer. Graphical abstract ᅟ.

Atherosclerosis is a vascular stem cell disease caused by insulin

The present article proposes the hypothesis that when multipotent vascular stem cells are exposed to excessive insulin in a rhythmic pattern of sharply rising and falling concentrations, their differentiation is misdirected toward adipogenic and osteogenic cell lineages. This results in plaque-like accumulation of adipocytes with fat and cholesterol deposition from adipocyte debris, and osteogenic (progenitor) cells with a calcified matrix in advanced lesions. The ingrowth of capillaries and infiltration with macrophages, which upon uptake of lipids turn into foam cells, are unspecific pro-resolving reactions. Epidemiological, histopathological, pharmacological, and experimental evidence in favour of this hypothesis is summarised.

The Effect of Low-Carbohydrate Diet on Glycemic Control in Patients with Type 2 Diabetes Mellitus

Objective: In China, a low-fat diet (LFD) is mainly recommended to help improve blood glucose levels in patients with type 2 diabetes mellitus (T2DM). However, a low-carbohydrate diet (LCD) has been shown to be effective in improving blood glucose levels in America and England. A few studies, primarily randomized controlled trials, have been reported in China as well. Method: Firstly, we designed two ‘six-point formula’ methods, which met the requirements of LCD and LFD, respectively. Fifty-six T2DM patients were recruited and randomly allocated to the LCD group (n = 28) and the LFD group (n = 28). The LCD group received education about LCD’s six-point formula, while the LFD group received education about LFD’s six-point formula. The follow-up time was three months. The indicators for glycemic control and other metabolic parameters were collected and compared between the two groups. Results: Forty-nine patients completed the study. The proportions of calories from three macronutrients the patients consumed met the requirements of LCD and LFD. Compared to the LFD group, there was a greater decrease in HbA1c level in the LCD group (−0.63% vs. −0.31%, p < 0.05). The dosages of insulin and fasting blood glucoses (FBG) in the third month were lower than those at baseline in both groups. Compared with baseline values, body mass index (BMI) and total cholesterol (TC) in the LCD group were significantly reduced in the third month (p < 0.05); however, there were no statistically significant differences in the LFD group. Conclusions: LCD can improve blood glucose more than LFD in Chinese patients with T2DM. It can also regulate blood lipid, reduce BMI, and decrease insulin dose in patients with T2DM. In addition, the six-point formula is feasible, easily operable, and a practical educational diet for Chinese patients with T2DM.

Making the Most of Continuing Medical Education: Evidence of Transformative Learning During a Course in Evidence-Based Medicine and Decision Making

INTRODUCTION

Continuing medical information courses have been criticized for not promoting behavior change among their participants. For behavior change to occur, participants often need to consciously reject previous ideas and transform their way of thinking. Transformational learning is a process that cultivates deep emotional responses and can lead to cognitive and behavioral change in learners, potentially facilitating rich learning experiences and expediting knowledge translation. We explored participants' experiences at a 2-day conference designed to support transformative learning as they encounter new concepts within Information Mastery, which challenge their previous frameworks around the topic of medical decision making. Using the lens of transformative learning theory, we asked: how does Information Mastery qualitatively promote perspective transformation and hence behavior change?

METHODS

We used a hermeneutic phenomenologic approach to capture the lived experience of 12 current and nine previous attendees of the "Information Mastery" course through individual interviews, focus groups, and observation. Data were thematically analyzed.

RESULTS

Both prevoius and current conference attendees described how the delivery of new concepts about medical decision making evoked strong emotional responses, facilitated personal transformation, and propelled expedited behavior change around epistemological, moral, and information management themes, resulting in a newfound sense of self-efficacy, confidence, and ownership in their ability to make medical decisions.

DISCUSSION

When the topic area holds the potential to foster a qualitative reframing of learners' guiding paradigms and worldviews, attention should be paid to supporting learners' personalized meaning-making process through transformative learning opportunities to promote translation into practice.

Targeting the Warburg effect for cancer treatment: Ketogenic diets for management of glioma

Gliomas are a highly heterogeneous tumor, refractory to treatment and the most frequently diagnosed primary brain tumor. Although the current WHO grading system (2016) demonstrates promise towards identifying novel treatment modalities and better prediction of prognosis over time, to date, existing targeted and mono therapy approaches have failed to elicit a robust impact on disease progression and patient survival. It is possible that tumor heterogeneity as well as specifically targeted agents fail because redundant molecular pathways in the tumor make it refractory to such approaches. Additionally, the underlying metabolic pathology, which is significantly altered during neoplastic transformation and tumor progression, is unaccounted for. With several molecular and metabolic pathways implicated in the carcinogenesis of CNS tumors, including glioma, we postulate that a systemic, broad spectrum approach to produce robust targeting of relevant and multiple molecular and metabolic regulation of growth and survival pathways, critical to the modulation of hallmarks of carcinogenesis, without clinically limiting toxicity, may provide a more sustained impact on clinical outcomes compared to the modalities of treatment evaluated to date. The objective of this review is to examine the emerging hallmark of reprogramming energy metabolism of the tumor cells and the tumor microenvironment during carcinogenesis, and to provide a rationale for exploiting this hallmark and its biological capabilities as a target for secondary chemoprevention and treatment of glioma. This review will primarily focus on interventions to induce ketosis to target the glycolytic phenotype of many cancers, with specific application to secondary chemoprevention of low grade glioma- to halt the progression of lower grade tumors to more aggressive subtypes, as evidenced by reduction in validated intermediate endpoints of disease progression including clinical symptoms.

Cannabimimetic phytochemicals in the diet - an evolutionary link to food selection and metabolic stress adaptation?

The endocannabinoid system (ECS) is a major lipid signalling network that plays important pro-homeostatic (allostatic) roles not only in the nervous system but also in peripheral organs. There is increasing evidence that there is a dietary component in the modulation of the ECS. Cannabinoid receptors in hominids co-evolved with diet, and the ECS constitutes a feedback loop for food selection and energy metabolism. Here, it is postulated that the mismatch of ancient lipid genes of hunter-gatherers and pastoralists with the high-carbohydrate diet introduced by agriculture could be compensated for via dietary modulation of the ECS. In addition to the fatty acid precursors of endocannabinoids, the potential role of dietary cannabimimetic phytochemicals in agriculturist nutrition is discussed. Dietary secondary metabolites from vegetables and spices able to enhance the activity of cannabinoid-type 2 (CB₂ ) receptors may provide adaptive metabolic advantages and counteract inflammation. In contrast, chronic CB₁ receptor activation in hedonic obese individuals may enhance pathophysiological processes related to hyperlipidaemia, diabetes, hepatorenal inflammation and cardiometabolic risk. Food able to modulate the CB₁ /CB₂ receptor activation ratio may thus play a role in the nutrition transition of Western high-calorie diets. In this review, the interplay between diet and the ECS is highlighted from an evolutionary perspective. The emerging potential of cannabimimetic food as a nutraceutical strategy is critically discussed.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

Hyperbaric Environment: Oxygen and Cellular Damage versus Protection

The elevation of tissue pO2 induced by hyperbaric oxygen (HBO) is a physiological stimulus that elicits a variety of cellular responses. These effects are largely mediated by, or in response to, an increase in the production of reactive oxygen and nitrogen species (RONS). The major consequences of elevated RONS include increased oxidative stress and enhanced antioxidant capacity, and modulation of redox-sensitive cell signaling pathways. Interestingly, these phenomena underlie both the therapeutic and potentially toxic effects of HBO. Emerging evidence indicates that supporting mitochondrial health is a potential method of enhancing the therapeutic efficacy of, and preventing oxygen toxicity during, HBO. This review will focus on the cellular consequences of HBO, and explore how these processes mediate a delicate balance of cellular protection versus damage. © 2017 American Physiological Society. Compr Physiol 7:213-234, 2017.

Critical review of bariatric surgery, medically supervised diets, and behavioural interventions for weight management in adults

AIMS

Patient selection of weight management treatment option is often guided by a variety of factors. Currently, there is no comprehensive tool to facilitate informed decision-making for patients and clinicians. This article aims to synthesise evidence on the treatment effectiveness, health benefits, risks, and patient experiences of treatment options presently available at the Weight Management Clinic at The Ottawa Hospital (TOH), as a first step towards developing a decision aid.

METHODS

Narrative and systematic reviews published in English between 1999 and 2014 were included that focused on one or more of the following weight management treatments in adults aged 18 years and over: roux-en-y gastric bypass (RYGB), sleeve gastrectomy (SG), medically supervised meal replacement, and behavioural or lifestyle intervention.

RESULTS

Overall, bariatric surgeries have received the greatest research attention and have been associated not only with greater weight loss and health benefit but also with greater risks, complications, and financial cost. Dietary programmes demonstrated weight loss and health benefits to a lesser extent than with surgery but were associated with lower and shorter-term risks and complications. Behavioural and lifestyle interventions have been studied less yet have shown significant, albeit small, weight loss outcomes alone and in combination with dietary or surgical options; they also appear to be the lowest risk interventions. Patient experiences of weight management options are mixed and not well understood.

CONCLUSION

Further research is needed; however, this review identified some general trends related to weight loss outcomes, benefits, risks, and barriers for weight management options that have implications for shared treatment decision-making.

Caloric Restriction as a Strategy to Improve Vascular Dysfunction in Metabolic Disorders

Caloric restriction (CR) has proved to be the most effective and reproducible dietary intervention to increase healthy lifespan and aging. A reduction in cardiovascular disease (CVD) risk in obese subjects can be already achieved by a moderate and sustainable weight loss. Since pharmacological approaches for body weight reduction have, at present, a poor long-term efficacy, CR is of great interest in the prevention and/or reduction of CVD associated with obesity. Other dietary strategies changing specific macronutrients, such as altering carbohydrates, protein content or diet glycemic index have been also shown to decrease the progression of CVD in obese patients. In this review, we will focus on the positive effects and possible mechanisms of action of these strategies on vascular dysfunction.

Metabolic Correction in Patients Sample with Diabetes: Clinical Outcomes and Costs Reductions

Diabetes is a leading cause of mortality and morbidity worldwide. Diabetes complications produce profound impact on patient's quality of life and represent very significant economic cost to patients, their family, the government and society as a whole. Metabolic correction has been proposed as an efficient method to improve clinical outcomes and reduce costs in diabetes. Metabolic correction is a concept that supports health maintenance and promotes the healing processes by improving the body's biochemical-physiological mechanisms. This is done by helping activate the metabolic enzymes necessary to facilitate key physiological pathways. A group of 50 patients followed a simple metabolic correction strategy based on hydration, diet, and magnesium supplementation during a 6 months period. Outcomes measures included laboratory testing, anthropometric measures and medication use including its related costs. Patients had an average weight loss of 9.4 lbs (↓5.0%) from baseline at month 3 and 12 lbs (↓6.4%) at month 6. Waist circumference decreased on average 3.7 inches (↓9.0%) from baseline at month 3 and had further decrease to 5.5 inches (↓13.4%) from baseline at month 6. Laboratory testing of average triglycerides decreased from a baseline of 156.9 to 116.7 (↓25.6%) at month 3 and maintained a reduction of ↓24.2% by month 6. Total cholesterol concentration decreased from a baseline of 181.1 mg/dL to 173.9 (↓4.0%) in month 3 and to 171.1 (↓5.5%) at month 6. Average HgA1c decreased from baseline of 7.17 to 6.52 (↓9.1%) at month 3 and maintained 6.52 at months 6. The atherogenic index decreased from 4.18 at baseline to 3.85 at month 3 (↓7.9%) and then 3.47 (17.0%) at month 6. Medication use and cost was quantified in various ways. The average baseline monthly diabetes medication cost per patient of $124.10 was reduced to $ 78.23 (↓36.7% reduction) at month 3 and to $62.80 (↓49.4% reduction) at month 6. A simple and well structured metabolic correction program that includes a significant educational component, dietary modifications and dietary supplement intake was able to maintain or improve vital signs, anthopometric and laboratory measurements that correlate with improved clinical diabetes and cardiovascular health. This outcome was achieved while decreasing the use medications at month 3 and 6 at significant cost savings.

Low Carbohydrate Diets and Type 2 Diabetes: What is the Latest Evidence?

INTRODUCTION

Low carbohydrate diets are again in the spotlight and have been identified as particularly appropriate for people with type 2 diabetes. There is confusion amongst both health professionals and people with diabetes about the suitability of these diets. This review aims to provide an overview of the latest evidence and to explore the role of low carbohydrate diets for people with type 2 diabetes.

METHODS

An electronic search of English language articles was performed using MEDLINE (2010-May 2015), EMBASE (2010-May 2015), and the Cochrane Central Register of Controlled Trials (2010-May 2015). Only randomized controlled trials comparing interventions evaluating reduced carbohydrate intake with higher carbohydrate intake in people with diagnosed type 2 diabetes were included. Primary outcomes included weight, glycated hemoglobin, and lipid concentrations.

RESULTS

Low carbohydrate diets in people with type 2 diabetes were effective for short-term improvements in glycemic control, weight loss, and cardiovascular risk, but this was not sustained over the longer term. Overall, low carbohydrate diets failed to show superiority over higher carbohydrate intakes for any of the measures evaluated including weight loss, glycemic control, lipid concentrations, blood pressure, and compliance with treatment.

CONCLUSION

Recent studies suggest that low carbohydrate diets appear to be safe and effective over the short term, but show no statistical differences from control diets with higher carbohydrate content and cannot be recommended as the default treatment for people with type 2 diabetes.

Calories, carbohydrates, and cancer therapy with radiation: exploiting the five R's through dietary manipulation

Aggressive tumors typically demonstrate a high glycolytic rate, which results in resistance to radiation therapy and cancer progression via several molecular and physiologic mechanisms. Intriguingly, many of these mechanisms utilize the same molecular pathways that are altered through calorie and/or carbohydrate restriction. Furthermore, poorer prognosis in cancer patients who display a glycolytic phenotype characterized by metabolic alterations, such as obesity and diabetes, is now well established, providing another link between metabolic pathways and cancer progression. We review the possible roles for calorie restriction (CR) and very low carbohydrate ketogenic diets (KDs) in modulating the five R's of radiotherapy to improve the therapeutic window between tumor control and normal tissue complication probability. Important mechanisms we discuss include (1) improved DNA repair in normal, but not tumor cells; (2) inhibition of tumor cell repopulation through modulation of the PI3K-Akt-mTORC1 pathway downstream of insulin and IGF1; (3) redistribution of normal cells into more radioresistant phases of the cell cycle; (4) normalization of the tumor vasculature by targeting hypoxia-inducible factor-1α downstream of the PI3K-Akt-mTOR pathway; (5) increasing the intrinsic radioresistance of normal cells through ketone bodies but decreasing that of tumor cells by targeting glycolysis. These mechanisms are discussed in the framework of animal and human studies, taking into account the commonalities and differences between CR and KDs. We conclude that CR and KDs may act synergistically with radiation therapy for the treatment of cancer patients and provide some guidelines for implementing these dietary interventions into clinical practice.

Carbohydrates and endothelial function: is a low-carbohydrate diet or a low-glycemic index diet favourable for vascular health?

Low-carbohydrate diets have become increasingly popular in both media and clinical research settings. Although they may improve some metabolic markers, their effects on arterial function remain unclear. Endothelial dysfunction is the well-established response to cardiovascular risk factors and a pivotal feature that precedes atherosclerotic diseases. It has been demonstrated that a high carbohydrate-induced hyperglycemia and subsequent oxidative stress acutely worsen the efficacy of the endothelial vasodilatory system. Thus, in theory, a carbohydrate restricted diet may preserve the integrity of the arterial system. This review attempts to provide insight on whether low-carbohydrate diets have a favorable or detrimental impact on vascular function, or it is perhaps the quality of carbohydrate that should direct dietary recommendations. Research to date suggests that diets low in carbohydrate amount may negatively impact vascular endothelial function. Conversely, it appears that maintaining recommended carbohydrate intake with utilization of low glycemic index foods generates a more favorable vascular profile. Understanding these relationships will aid in deciphering the diverging role of modulating quantity and quality of carbohydrates on cardiovascular risk.

Effect of a 1-week, eucaloric, moderately high-fat diet on peripheral insulin sensitivity in healthy premenopausal women

OBJECTIVES

To determine whether a weight-maintaining, moderate (50%) high-fat diet is deleterious to insulin sensitivity in healthy premenopausal women.

DESIGN/SETTING/PARTICIPANTS

23 African-American and non-Hispanic white, healthy, overweight, and obese premenopausal women recruited in New York City, USA, fed either a eucaloric, 1-week long high-fat (50% of total Kcal from fat) diet or a eucaloric, 1-week long low-fat (30% of total Kcal from fat) diet, assigned in a randomized crossover design.

MAIN OUTCOME MEASURES

Peripheral insulin sensitivity and metabolic flexibility during a euglycemic hyperinsulinemic (80 mU/m(2)/min) clamp measured during the follicular phase of the menstrual cycle, at the end of each diet period.

RESULTS

Peripheral insulin sensitivity (mg kg/fat-free mass/min (µU/mL)×10(-1)) was not decreased after the high-fat diet vs the low-fat diet (0.09±0.01 vs 0.08±0.01, p=0.09, respectively) in the combined group of African-American and white women, with no significant diet by race interaction (p=0.6). Metabolic flexibility (change in substrate utilization, ΔNPRQ, in response to insulin during the clamp) was similarly unaltered by the diet (0.12±0.01 vs 0.11, p=0.48, for the high-fat diet vs the low-fat diet, respectively) in the combined group of women, with no significant diet by race interaction (p=0.9). African-American women had a lower insulin clearance compared with the white women, regardless of the diet (p<0.05).

CONCLUSIONS

We conclude that a short term (1 week), moderate (50%), eucaloric high-fat diet does not lower peripheral insulin sensitivity in healthy, overweight and obese premenopausal women.