Clinical Evidence and Mechanisms of High-Protein Diet-Induced Weight Loss

Common questions and misconceptions about protein supplementation: what does the scientific evidence really show?

Protein supplementation often refers to increasing the intake of this particular macronutrient through dietary supplements in the form of powders, ready-to-drink shakes, and bars. The primary purpose of protein supplementation is to augment dietary protein intake, aiding individuals in meeting their protein requirements, especially when it may be challenging to do so through regular food (i.e. chicken, beef, fish, pork, etc.) sources alone. A large body of evidence shows that protein has an important role in exercising and sedentary individuals. A PubMed search of "protein and exercise performance" reveals thousands of publications. Despite the considerable volume of evidence, it is somewhat surprising that several persistent questions and misconceptions about protein exist. The following are addressed: 1) Is protein harmful to your kidneys? 2) Does consuming "excess" protein increase fat mass? 3) Can dietary protein have a harmful effect on bone health? 4) Can vegans and vegetarians consume enough protein to support training adaptations? 5) Is cheese or peanut butter a good protein source? 6) Does consuming meat (i.e., animal protein) cause unfavorable health outcomes? 7) Do you need protein if you are not physically active? 8) Do you need to consume protein ≤ 1 hour following resistance training sessions to create an anabolic environment in skeletal muscle? 9) Do endurance athletes need additional protein? 10) Does one need protein supplements to meet the daily requirements of exercise-trained individuals? 11) Is there a limit to how much protein one can consume in a single meal? To address these questions, we have conducted a thorough scientific assessment of the literature concerning protein supplementation.

Associations Between Body Weight Dissatisfaction and Diet Quality in Women With a Body Mass Index in the Healthy Weight Category: Results From the 2014-2015 Swiss National Nutrition Survey

BACKGROUND

Few studies have examined whether diet quality is lower in women with body weight dissatisfaction compared with women without body weight dissatisfaction.

OBJECTIVES

(1) Examine the association between body weight dissatisfaction and diet quality among women (18-65 years old) in the healthy weight body mass index (BMI) category, and (2) explore dietary and behavioral patterns among women with body weight dissatisfaction.

DESIGN

Data were extracted from the cross-sectional 2014-2015 Swiss National Nutrition Survey.

PARTICIPANTS/SETTING

Population-based sample of 507 women with BMI ≥ 18.5 and < 25.

OUTCOME MEASURES

Dietary intakes assessed by registered dietitians using 2 nonconsecutive computer-assisted multi-pass 24-hour dietary recalls. Diet quality was measured with a slightly modified version of the Healthy Eating Index (HEI)-2020.

STATISTICAL ANALYSES PERFORMED

Multiple linear regressions were performed to test the association between body weight dissatisfaction and total HEI-2020 score. Hierarchical cluster analysis was used to identify subgroups of women with body weight dissatisfaction.

RESULTS

Body weight dissatisfaction was not found to be associated with diet quality (β = -1.73 [-4.18; 0.71], P = .16). However, women who were dissatisfied with their body weight had lower scores for the HEI-2020 total fruits (P = .050) and whole grains (P = .014) components than women who were satisfied with their body weight. Four profiles with different dietary patterns were identified among women with body weight dissatisfaction: "Unhealthy diet with dairy," "Protein and fat," "Vegetables without protein," and "Healthier diet without dairy."

CONCLUSIONS

Among women with a BMI in the healthy weight category, overall diet quality was not observed to differ between those with or without body weight dissatisfaction. More research is needed to explore the different profiles of dietary intake in women with body weight dissatisfaction.

Associations of Amino Acids with the Risk of Prediabetes: A Case-Control Study from Kazakhstan

BACKGROUND

The high global prevalence of prediabetes requires its early identification. Amino acids (AAs) have emerged as potential predictors of prediabetes. This study investigates the association between amino acids and prediabetes in the Kazakh population.

MATERIALS AND METHODS

In this case-control study, serum AAs levels were measured using the Trace GC 1310 gas chromatography system coupled with the TSQ 8000 triple quadrupole mass spectrometer (Thermo Scientific, Austin, TX, USA) followed by silylation with the BSTFA + 1% TMCS derivatization method. Biochemical parameters, including total cholesterol, HDL-C, LDL-C, triglycerides, fasting glucose, HbA1c, and Creatinine, were assessed for each participant. Trained professionals conducted anthropometric and physical examinations (which included taking blood pressure and heart rate measurements) and family history collection.

RESULTS

A total of 112 Kazakh individuals with prediabetes and 55 without prediabetes, aged 36-65 years, were included in the study. Only Alanine and valine showed a significant association with prediabetes risk among the 13 AAs analyzed. Our findings revealed an inverse relationship between Alanine and Valine and prediabetes in individuals of Kazakh ethnicity.

CONCLUSION

A lower serum level of Alanine and Valine may serve as a predictive biomarker for prediabetes in the Kazakh population.

Anti-Obesity Effects of a Collagen with Low Digestibility and High Swelling Capacity: A Human Randomized Control Trial

BACKGROUND/OBJECTIVES

Collagen is a protein formed by very long amino acid chains. When conveniently treated, it can incorporate water into the net, thus increasing its volume and mass. The present work aimed to evaluate the potential anti-obesity effects of bovine collagen that has been technologically treated to increase its water retention capacity in an acid pH medium, with the objective of inducing satiation.

METHODS

Collagen's digestibility was tested with a pepsin digestion test. Its swelling capacity was tested in an acid pH medium simulating gastric conditions. Postprandial levels of ghrelin in response to collagen supplementation were tested in rats. In a randomized control trial, 64 subjects with overweight/obesity were allocated in two groups: supplemented daily with two protein bars enriched with collagen (20 g per day) for 12 weeks, or control group. Anthropometric and biochemical measurements were assessed in all the participants.

RESULTS

This collagen showed a low digestibility (<60%) and high swelling capacity (>1900%) in vitro. In humans with overweight and obesity, this collagen significantly reduced body weight, body mass index (BMI), systolic blood pressure (SBP), and fatty liver index (FLI) and increased fat-free mass when compared with the control group. A significant reduction in the sarcopenic index; total, troncular, and visceral fat (measured by DEXA); and serum leptin levels were observed in the collagen group at the end of the intervention, with no differences with respect to controls. Collagen reduced the sensation of hunger and increased fullness and satisfaction. In male Wistar rats, collagen decreased postprandial blood ghrelin levels.

CONCLUSIONS

Collagen supplementation (20 g per day for 12 weeks) reduced body weight, BMI, waist circumference, fat mass, FLI, and SBP in humans with overweight and obesity, which might be related to the increased sensation of fullness and satisfaction reported by the volunteers after the intake.

Low-calorie, high-protein diets, regardless of protein source, improve glucose metabolism and cardiometabolic profiles in subjects with prediabetes or type 2 diabetes and overweight or obesity

AIM

The aim was to study the effect of two low-calorie, high-protein (HP) diets, with most of the protein coming from animal or plant sources, on glycaemic and other cardiometabolic outcomes in subjects with overweight or obesity and glucose metabolism disorders.

MATERIALS AND METHODS

A total of 117 participants aged >18 years with body mass index over 27.5 kg/m2 and prediabetes or type 2 diabetes mellitus (T2DM) were randomized to one of two HP low-calorie diets (35% of total calories from protein), in which 75% of the protein was from either plant-based sources (HPP) or animal sources (HPA). For both diets, 30% and 35% of the total calories were from fat and carbohydrates, respectively. The dietary intervention lasted 6 months.

RESULTS

Both diets improved body composition to a similar extent, including weight loss (-8.05 ± 5.12 kg for the HPA diet and -7.70 ± 5.47 kg for the HPP diet at 6 months) and fat mass, mainly visceral fat. Both diets had a similar beneficial effect on glucose metabolism, including fasting glucose, insulin, homeostasis model assessment of insulin resistance index and glycated haemoglobin. Other biochemical parameters, including lipid profiles, liver enzymes, adipokines and inflammatory biomarkers, similarly improved in both groups. Fasting incretins, mainly glucagon-like peptide 1, decreased significantly in both groups, and this effect correlated with weight loss.

CONCLUSIONS

Low-calorie HP diets improved body composition, glucose metabolism and other cardiometabolic outcomes, regardless of protein source (either animal or plant sources), in outpatients with prediabetes or T2DM.

CLINICAL TRIAL REGISTRATION

The clinical trial was registered in ClinicalTrials.gov (identifier: NCT05456347) https://clinicaltrials.gov/study/NCT05456347?term=NCT05456347&rank=1.

Lumbar localized fat distribution parameters are independent predictors of osteoporotic vertebral compression re-fractures (OVCRFs) following Percutaneous Kyphoplasty (PKP): a retrospective matched case-control study

OBJECTIVE

To investigate potential risk factors for osteoporotic vertebral compression re-fractures (OVCRFs) following percutaneous kyphoplasty (PKP).

MATERIALS AND METHODS

Patients who underwent PKP from January 2012 to January 2020 were included in this study within the same institution. Cases were defined as patients who experienced OVCRFs, while controls were matched based on corresponding clinical characteristics from those patients without OVCRFs. The lumbar localized fat distribution parameters, including the fat infiltration ratio (FIR) in muscles [multifidus (MF), erector spinae (ES), paravertebral muscles (PVM), and psoas major (PS)] and subcutaneous fat thickness (SFT), were compared between the two groups through radiological data. And other clinical data that may be relevant were also compared. Independent risk factors for OVCRFs after PKP were identified through a binary logistic regression analysis.

RESULT

A total of 1391 patients who underwent PKP were included in this study. 51 patients were categorized into the re-fracture group, and 102 patients were selected as matched controls from the remaining cohort. There were statistically significant differences between the two groups in metrics including MF-FIR, ES-FIR, PVM-FIR, PS-FIR, bone mineral density (BMD), body-mass index (BMI), SFT, hemoglobin (Hb), albumin (ALB), alkaline phosphatase (ALP), and triglycerides (TG) (P < 0.05). Binary logistic regression analysis demonstrated that PVM-FIR (P = 0.003), SFT (P < 0.001), BMD (P = 0.011), and ALP (P = 0.005) were independent predictors for the occurrence of OVCRFs.

CONCLUSION

This study discovered that lumbar localized fat distribution parameters including PVM-FIR and SFT are independent predictors of OVCRFs. Additionally, BMD and ALP were found to be independent predictors of OVCRFs.

Efficacy of a High-Protein Diet to Lower Glycemic Levels in Type 2 Diabetes Mellitus: A Systematic Review

Diabetes is a metabolic disease with a high worldwide prevalence and an important factor in mortality and disability in the population. Complications can be reduced or prevented with lifestyle changes in physical activity, dietary habits, and smoking cessation. High-protein diets (HPDs, >30% or >1.0 g/Kg/day) decrease hyperglycemia in part due to their content of branched-chain amino acids (BCAAs), mainly leucine. Leucine (and other BCAAs) improve glucose metabolism by directly signaling in the medio-basal hypothalamus (MBH), increasing liver insulin sensitivity. To determine the effectiveness of an HPD to lower hyperglycemia, we analyzed the results of published clinical studies focusing on the levels of fasting plasma glucose and/or glycosylated hemoglobin (HbA1c) in patients with type 2 diabetes mellitus (T2DM). We carried out a systematic search for clinical studies using HPDs. We searched five databases (Scopus, Web of Science, PubMed, Epistemonikos, and Cochrane), collecting 179 articles and finally selecting 8 articles to analyze their results. In conclusion, HPDs are an effective alternative to reduce hyperglycemia in patients with T2DM, especially so-called Paleolithic diets, due to their higher-quality protein from animal and vegetal sources and their exclusion of grains, dairy products, salt, refined fats, and added sugars.

Duckweed protein: Extraction, modification, and potential application

Discovering alternative protein sources that are both nutritious and environmentally friendly is essential to meet the growing global population's needs. Duckweed offers promise due to its cosmopolitan distribution, rapid growth, high protein content, and scalability from household tanks to large lagoons without requiring arable land that competes for the major crops. Rich in essential amino acids, particularly branched-chain amino acids, duckweed supports human health. Extraction methods, such as ultrasound and enzymatic techniques, enhance protein yield compared to traditional methods. However, low protein solubility remains a challenge, addressed by protein modification techniques (physical, chemical, and biological) to broaden its applications. Duckweed proteins hold potential as functional food ingredients due to their unique physicochemical properties. This review also includes patents and regulations related to duckweed protein, filling a gap in current literature. Overall, duckweed presents a sustainable protein source with a lower environmental impact compared to conventional crops.

Enhanced protein intake on maintaining muscle mass, strength, and physical function in adults with overweight/obesity: A systematic review and meta-analysis

BACKGROUND & AIMS

Weight loss in individuals with obesity and overweight leads to metabolic and health benefits but also poses the risk of muscle mass reduction. This systematic review and meta-analysis of randomized controlled trials aims to determine the initial protein amount necessary for achieving weight loss while maintaining muscle mass, strength, and physical function in adults with overweight and obesity.

METHODS

Relevant literature databases, including Medical Literature Analysis and Retrieval System Online (Medline), Excerpta Medica (Embase), the Cumulative Index to Nursing and Allied Health Literature (CINHAL), and Web of Science, were electronically searched up to 15 March 2023. We examined the effect of additional protein intake on muscle mass, strength, and physical function in adults with overweight or obesity targeting weight loss. The risk of bias was assessed using the Cochrane RoB 2.0 tool. Results were synthesized using standardized mean differences (SMD) and 95% confidence intervals (CI) via a random-effects model.

RESULTS

Forty-seven studies (n = 3218) were included. In the muscle mass analysis, twenty-eight trials with 1989 participants were encompassed. Results indicated that increased protein intake significantly prevents muscle mass decline in adults with overweight or obesity aiming for weight loss (SMD 0.75; 95% CI 0.41 to 1.10; p < 0.001). Enhanced protein intake did not significantly prevent decreases in muscle strength and physical function. An intake exceeding 1.3 g/kg/day is anticipated to increase muscle mass, while an intake below 1.0 g/kg/day is associated with a higher risk of muscle mass decline. The risk of bias in studies regarding muscle mass ranged from low to high.

CONCLUSIONS

Adults with overweight or obesity and aim for weight loss can more effectively retain muscle mass through higher protein intake, as opposed to no protein intake enhancement.

A double-blind, randomized control trial to investigate the therapeutic potential of garlic scapes for high apoprotein E levels in a high-Fat diet-induced hypercholesteremic rat model

Hypercholesteremia is the main contributor to metabolic diseases, including obesity, hypertension, and diabetes, which are the primary global sources of morbidity and death rates. Garlic scapes, a member of the Allium sativum family and a rich source of antioxidants, are utilized in various cuisine preparations due to their unique flavors and tastes. The current study examined garlic scape powder's effect on apoprotein E and its ability to decrease cholesterol. In an in vivo experiment, normal, healthy Wistar albino rats (weeks) were divided into a negative control group (NC, n = 10) and a high-fat diet-raised group (n = 50) until they achieved cholesterol ≥250 mg/dL. Hypercholesteremic rats were further divided randomly into five groups: positive control (PC), standard group (fenofibrate 20 mg/kg bwt), and treatment groups G1, G2, and G3 that were administered with garlic scape powder 400 mg, 800 mg, and 1200 mg/kg bwt orally, respectively, for 3 months. The blood samples were examined for cholesterol, triglycerides, high-density lipoproteins (HDLs), low-density lipoproteins, apoprotein E, albumin levels, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). The liver tissues of the rats were subjected to histopathology. The lipid profile was assessed using serum kit techniques, whereas an ELISA kit was used to evaluate apoprotein E, and a serum kit was used to estimate ALT and AST. In comparison to all other groups except NC, the highest dose of 1200 mg/kg bwt of garlic scapes significantly (p ≤ .05) increased serum insulin (13.66 ± 0.72 μU/mL), apoprotein E levels (6.08 ± 0.10 mg/dL), HDL (42.1 ± 1.81 mg/dL), and reduce TG (88.7 ± 1.64 mg/dL) and decreased overall cholesterol levels (67.9 ± 1.17 mg/dL). Except for NC, all treatment groups had significantly (p ≤ .05) lower ALT and AST values than PC. To sum up, powdered garlic scapes may be a great way to avoid hyperlipidemia, which raises the risk of cardiovascular illnesses. ALT and AST levels were significantly (p ≤ .05) reduced in all treatment groups compared to PC, except for NC. In conclusion, garlic scape powder may be an excellent source to prevent hyperlipidemia, a risk factor for cardiovascular diseases. In addition, powdered garlic scapes supplementation at high doses may be used as an alternative natural source in functional foods to halt hyperlipidemia without liver toxicity in the long term.

Contrasting Effects of an Atherogenic Diet and High-Protein/Unsaturated Fatty Acids Diet on the Accelerated Aging Mouse Model SAMP8 Phenotype

Background/Objectives: Aging has been extensively studied, with a growing interest in memory impairment by a neurobiological approach. Mitochondrial dysfunction is a hallmark of aging, contributing to the aging phenotype; therefore, mitochondrial interventions seem fundamental. The diet is a physiological approximation for modifying mitochondria, which could impact the age-related phenotype. Methods: We studied two diets with low-carbohydrate and high-fat compositions, differing in the amount of protein and the fat type disposable-the atherogenic diet Cocoa (high protein/high saturated fat/high cholesterol) and the South Beach diet (very high-protein/high-unsaturated fat)-on oxidative stress, mitochondrial state, and hippocampus-dependent memory in 3-month-old Senescence-Accelerated Mouse Model (SAMP8) seed over 3 months to determine their pro- or anti-aging effects. Results: Despite its bad reputation, the Cocoa diet reduces the reactive oxygen species (ROS) content without impacting the energy state and hippocampus-dependent spatial acuity. In contrast to the beneficial impact proposed for the South Beach diet, it induced a pro-aging phenotype, increasing oxidative damage and the levels of NR2B subunit of the NMDA, impairing energy and spatial acuity. Surprisingly, despite the negative changes observed with both diets, this led to subtle memory impairment, suggesting the activation of compensatory mechanisms preventing more severe cognitive decline. Conclusions: Our results demonstrated that diets usually considered good could be detrimental to the onset of aging. Also, probably due to the brain plasticity of non-aged animals, they compensate for the damage, preventing a more aggravated phenotype. Nevertheless, these silent changes could predispose or increase the risk of suffering pathologies at advanced age.

Effectiveness of a protein-supplemented very-low-calorie diet program for weight loss: a randomized controlled trial in South Korea

Introduction

Weight-loss strategies through meal replacements are effective and sustainable options. However, few studies have assessed their effects on weight loss including body composition through protein-supplemented meal replacements targeting the Asian population, including Koreans. This study aimed to assess the effectiveness and safety of a protein-supplemented very-low-calorie diet (PSVLCD) for weight reduction and changes in body composition in individuals with obesity over a 12-month long-term period.

Methods

In total, 106 participants with obesity were randomly assigned to a PSVLCD or control group (food-based calorie-restricted diet). Body weight, waist circumference, body composition, and blood marker levels were measured throughout the study. Statistical analyses were performed to compare outcomes between the groups.

Results

Among the 106 participants, 84 completed the 12-month follow-up. Intention-to-treat analysis showed that the mean weight loss from baseline to 12 months was -6.86 kg (8.21% of baseline weight) in the PSVLCD group and - 4.66 kg (5.47% of initial body weight) in the control group; the difference was -2.20 kg with a marginally significant interval (95% confidence interval [CI], -4.90; 0.50). Waist circumference (-8.35 cm vs. -4.85 cm; mean difference, -3.49 cm; 95% CI, -6.48 to -0.50) and visceral fat area (-28.28 cm2 vs. -13.26 cm2; mean difference, -15.03cm2; 95% CI, -29.01 to -1.04) also significantly decreased in the PSVLCD group at 12 months.

Discussion

The PSVLCD group demonstrated a substantial initial reduction in waist circumference that was sustained over the study period, alongside a marginally significant decrease in weight. These findings suggest that a protein-supplemented very-low-calorie diet may be an effective strategy for long-term weight management and body composition improvement in individuals with obesity.

Clinical trial registration

ClinicalTrials.gov, identififer NCT04597788.

Nutritional Considerations During Major Weight Loss Therapy: Focus on Optimal Protein and a Low-Carbohydrate Dietary Pattern

PURPOSE OF REVIEW

Considering the high prevalence of obesity and related metabolic impairments in the population, the unique role nutrition has in weight loss, reversing metabolic disorders, and maintaining health cannot be overstated. Normal weight and well-being are compatible with varying dietary patterns, but for the last half century there has been a strong emphasis on low-fat, low-saturated fat, high-carbohydrate based approaches. Whereas low-fat dietary patterns can be effective for a subset of individuals, we now have a population where the vast majority of adults have excess adiposity and some degree of metabolic impairment. We are also entering a new era with greater access to bariatric surgery and approval of anti-obesity medications (glucagon-like peptide-1 analogues) that produce substantial weight loss for many people, but there are concerns about disproportionate loss of lean mass and nutritional deficiencies.

RECENT FINDINGS

No matter the approach used to achieve major weight loss, careful attention to nutritional considerations is necessary. Here, we examine the recent findings regarding the importance of adequate protein to maintain lean mass, the rationale and evidence supporting low-carbohydrate and ketogenic dietary patterns, and the potential benefits of including exercise training in the context of major weight loss. While losing and sustaining weight loss has proven challenging, we are optimistic that application of emerging nutrition science, particularly personalized well-formulated low-carbohydrate dietary patterns that contain adequate protein (1.2 to 2.0 g per kilogram reference weight) and achieve the beneficial metabolic state of euketonemia (circulating ketones 0.5 to 5 mM), is a promising path for many individuals with excess adiposity.

FoxO transcription factors regulate urea cycle through Ass1

When amino acids are plentiful in the diet, the liver upregulates most enzymes responsible for amino acid degradation. In particular, the activity of urea cycle enzymes increases in response to high-protein diets to facilitate the excretion of excess nitrogen. KLF15 has been established as a critical regulator of amino acid catabolism including ureagenesis and we have recently identified FoxO transcription factors as an important upstream regulator of KLF15 in the liver. Therefore, we explored the role of FoxOs in amino acid metabolism under high-protein diet. Our findings revealed that the concentrations of two urea cycle-related amino acids, arginine and ornithine, were significantly altered by FoxOs knockdown. Additionally, using KLF15 knockout mice and an in vivo Ad-luc analytical system, we confirmed that FoxOs directly regulate hepatic Ass1 expression under high-protein intake independently from KLF15. Moreover, ChIP analysis showed that the high-protein diet increased FoxOs DNA binding without altering the nuclear protein amount. Therefore, FoxOs play a direct role in regulating ureagenesis via a KLF15-independent pathway in response to high-protein intake.

A randomized controlled trial of a weight loss maintenance program in adults with obesity: the WLM3P study

BACKGROUND/OBJECTIVES

The escalating obesity epidemic necessitates effective, sustainable weight loss (WL) and maintenance strategies. This study aimed to evaluate the effectiveness of the Weight Loss Maintenance 3 Phases Program (WLM3P) in achieving a clinically significant long-term weight loss (WL) (≥5% initial WL at 18 months) in adults with obesity compared to a standard low-carbohydrate diet (LCD).

SUBJECTS/METHODS

In this two-phase trial, 112 participants targeting initial WL (0-6 months) and subsequent maintenance (7-18 months) were randomly assigned to either WLM3P or LCD groups. Outcomes assessed included change in body weight (kg, %), improvements in body composition, and metabolic profile.

RESULTS

Of 112 randomized participants, 69% (n = 77) completed the study. At 18 months, WL in the WLM3P group (n = 40) was 15.5 ± 8.3% compared to 9.6 ± 8.5% in the LCD group (n = 37) (p < 0.001). The odds ratio of achieving WL ≥ 10% and ≥15% were significantly higher in the WLM3P group. Complete-case analysis revealed significantly greater improvements in BMI, body fat mass, visceral fat area, waist circumference, waist-to-hip ratio, HDL, and triglyceride/HDL ratio in WLM3P than in LCD. No serious adverse events were reported.

CONCLUSION

Both programs effectively promoted clinically relevant WL and its maintenance. However, the WLM3P program was more successful in helping participants achieve greater WL targets of ≥10% and ≥15%, along with other clinical benefits, after an 18-month intervention.

TRIAL REGISTRATION NUMBER

NCT04192357.

Deciphering the complex interplay of obesity, epithelial barrier dysfunction, and tight junction remodeling: Unraveling potential therapeutic avenues

Obesity stands as a formidable global health challenge, predisposing individuals to a plethora of chronic illnesses such as cardiovascular disease, diabetes, and cancer. A confluence of genetic polymorphisms, suboptimal dietary choices, and sedentary lifestyles significantly contribute to the elevated incidence of obesity. This multifaceted health issue profoundly disrupts homeostatic equilibrium at both organismal and cellular levels, with marked alterations in gut permeability as a salient consequence. The intricate mechanisms underlying these alterations have yet to be fully elucidated. Still, evidence suggests that heightened inflammatory cytokine levels and the remodeling of tight junction (TJ) proteins, particularly claudins, play a pivotal role in the manifestation of epithelial barrier dysfunction in obesity. Strategic targeting of proteins implicated in these pathways and metabolites such as short-chain fatty acids presents a promising intervention for restoring barrier functionality among individuals with obesity. Nonetheless, recognizing the heterogeneity among affected individuals is paramount; personalized medical interventions or dietary regimens tailored to specific genetic backgrounds and allergy profiles may prove indispensable. This comprehensive review delves into the nexus of obesity, tight junction remodeling, and barrier dysfunction, offering a critical appraisal of potential therapeutic interventions.

Microbiota-bone axis in ageing-related bone diseases

Bone homeostasis in physiology depends on the balance between bone formation and resorption, and in pathology, this homeostasis is susceptible to disruption by different influences, especially under ageing condition. Gut microbiota has been recognized as a crucial factor in regulating host health. Numerous studies have demonstrated a significant association between gut microbiota and bone metabolism through host-microbiota crosstalk, and gut microbiota is even an important factor in the pathogenesis of bone metabolism-related diseases that cannot be ignored. This review explores the interplay between gut microbiota and bone metabolism, focusing on the roles of gut microbiota in bone ageing and aging-related bone diseases, including osteoporosis, fragility fracture repair, osteoarthritis, and spinal degeneration from different perspectives. The impact of gut microbiota on bone metabolism during aging through modification of endocrinology system, immune system and gut microbiota metabolites are summarized, facilitating a better grasp of the pathogenesis of aging-related bone metabolic diseases. This review offers innovative insights into targeting the gut microbiota for the treatment of bone ageing-related diseases as a clinical therapeutic strategy.

A protein-rich meal provides beneficial glycemic and hormonal responses as compared to meals enriched in carbohydrate, fat or fiber, in individuals with or without type-2 diabetes

Introduction

Diet stands as a pivotal modifiable risk factor influencing weight gain and the onset of type-2 diabetes (T2D). This study delves into the variation in glucose and regulatory pancreatic hormone levels subsequent to the consumption of meals with differing macronutrient compositions.

Methods

The cohort comprised 20 individuals diagnosed with T2D and 21 without diabetes. Participants underwent a cross-over design, consuming four isocaloric meals (600 kcal) enriched in carbohydrate, fiber, fat and protein. Plasma glucose, insulin and glucagon levels were measured at -30, and -5 min, followed by subsequent measurements every 30 min for 240 min post meal intake. Quantification of alterations in the postprandial state was accomplished through the incremental area under the curve (iAUC) and the incremental peak height for the insulin:glucagon ratio (IGR) and plasma glucose levels. The meal demonstrating the lowest responses across these variables was deemed the optimal meal.

Results

Meals rich in protein and fat, and consequently low in carbohydrate, exhibited reduced incremental peak and iAUC for both glucose and the IGR in comparison to the other meals. While the protein-enriched meal neared optimal standards, it proved less efficient for individuals without T2D and possessing a low BMI, as well as in those with T2D and poor glycemic control.

Conclusion

Our findings endorse the adoption of protein-enriched, low-carbohydrate meals to curtail the meal-induced anabolic hormonal response while averting excessive fluctuations in glucose levels.

Origin and Roles of Alanine and Glutamine in Gluconeogenesis in the Liver, Kidneys, and Small Intestine under Physiological and Pathological Conditions

Alanine and glutamine are the principal glucogenic amino acids. Most originate from muscles, where branched-chain amino acids (valine, leucine, and isoleucine) are nitrogen donors and, under exceptional circumstances, a source of carbons for glutamate synthesis. Glutamate is a nitrogen source for alanine synthesis from pyruvate and a substrate for glutamine synthesis by glutamine synthetase. The following differences between alanine and glutamine, which can play a role in their use in gluconeogenesis, are shown: (i) glutamine appearance in circulation is higher than that of alanine; (ii) the conversion to oxaloacetate, the starting substance for glucose synthesis, is an ATP-consuming reaction for alanine, which is energetically beneficial for glutamine; (iii) most alanine carbons, but not glutamine carbons, originate from glucose; and (iv) glutamine acts a substrate for gluconeogenesis in the liver, kidneys, and intestine, whereas alanine does so only in the liver. Alanine plays a significant role during early starvation, exposure to high-fat and high-protein diets, and diabetes. Glutamine plays a dominant role in gluconeogenesis in prolonged starvation, acidosis, liver cirrhosis, and severe illnesses like sepsis and acts as a substrate for alanine synthesis in the small intestine. Interactions among muscles and the liver, kidneys, and intestine ensuring optimal alanine and glutamine supply for gluconeogenesis are suggested.

Milk protein concentrate supplementation improved appetite, metabolic parameters, adipocytokines, and body composition in dieting women with obesity: a randomized controlled trial

BACKGROUND

Dairy consumption is associated with many health benefits. However, to our knowledge, no clinical trials examined the effects of milk protein concentrate (MPC) on metabolic health in overweight and obese adults. This study investigated the effect of supplementation with MPC on glycaemic status, lipid profile, biomarkers of inflammation, and anthropometric measurements in women with obesity under a weight loss diet.

METHODS

This is a single-blind, open-labelled, parallel-group, randomized trial. Forty-four healthy women with obesity were randomized into a control (n = 22) or MPC (n = 22) group. Participants in the MPC group were supplemented with 30 g of MPC per day for 8 weeks. Both groups were on a calorie-restricted diet plan with 800 Kcal lower intakes than their needs. Blood samples, dietary intake, and body composition were assessed before and after the intervention.

RESULTS

MPC group had a significantly lower body mass index (P = 0.009), waist circumference (P = 0.013), fat mass (P = 0.021), appetite score (P = 0.002), fasting blood sugar (P < 0.001), insulin (P = 0.027), low-density lipoprotein cholesterol (P = 0.025), and leptin (P = 0.014) levels and higher high-density lipoprotein cholesterol (P = 0.001) and adiponectin (P = 0.032) compared to the control group after supplementation. Lean body mass, total cholesterol, and triglyceride did not differ significantly (P > 0.05).

CONCLUSION

Daily intake of 30 g of MPC for 8 weeks may improve several anthropometric and metabolic markers in women with obesity under a hypocaloric diet.

[Strategies for the prevention and non-pharmacological treatment of obesity. Models of care]

The prevalence of obesity has increased in recent years worldwide. In this context, strategies for management obesity in primary care are essential. The first step in the treatment of obesity are lifestyle intervention programs. The three pillars of these programs, ideally of high intensity (high frequency of visits), are dietary intervention, exercise and behavioral therapy. There is no universal model of care for patients with obesity, but it must take into account key aspects, such as facilitating the access and adherence of the patient and a multidisciplinary and coordinated care among professionals at different levels of healthcare. The components of the model of care and its format should be defined according to the resources available and the characteristics of the population to be treated.

A dairy-based, protein-rich breakfast enhances satiety and cognitive concentration before lunch in overweight to obese young females: A randomized controlled crossover study

The purpose of this study was to investigate if consumption of a high-protein, low-carbohydrate breakfast (PRO) leads to a lower subsequent ad libitum energy intake at lunch and the rest of the day compared with ingestion of an isocaloric low-protein, high-carbohydrate breakfast (CHO) or no breakfast (CON). The study was designed as a randomized controlled 3-period crossover study. Thirty young (18-30 yr) females with overweight to obesity (body mass index >25 kg/m2) in random order completed 3 separate experimental days where they consumed either a PRO, CHO, or CON breakfast test meal followed by an ad libitum lunch meal 3 h after breakfast. Participants were allocated to a sequence group by their inclusion number. The PRO and CHO breakfasts were matched in dietary fiber and fat content. Energy intake at lunch was calculated and dietary records were obtained for the rest of the day to calculate the total daily energy intake and macronutrient intake. Ratings of appetite sensations between meals and palatability of the test meals were assessed using visual analog scale sheets in intervals ranging from 10 to 30 min. In addition, blood samples were obtained at multiple time points separated by 10 to 60 min intervals between breakfast and lunch and were analyzed for appetite-regulating gut hormones, insulin, and glucose. Finally, performance in a cognitive concentration test was tested 150 min after breakfast. Compared with CHO and CON, the area under the curves for satiety, fullness, and satisfaction in the 3 h after breakfast were significantly higher after PRO, whereas the areas under the curve for hunger, desire to eat, and prospective eating were significantly lower after PRO. The appetite-regulating gut hormones cholecystokinin, glucagon-like peptide-1, and ghrelin in the hours after breakfast, energy intake during the ad libitum lunch meal, and the total daily energy intake did not differ significantly between PRO, CHO, and CON. However, the cognitive concentration test score was 3.5 percentage points higher for PRO, but not CHO, versus CON. A dairy-based high-protein, low-carbohydrate breakfast increased satiety sensation in the hours after breakfast but did not reduce total daily energy intake compared with an isocaloric low-protein, high-carbohydrate breakfast or omitting breakfast. However, performance in a cognitive concentration test before lunch was enhanced after the high-protein, low-carbohydrate breakfast, but not the low-protein, high-carbohydrate breakfast, compared with omitting breakfast.

A Narrative Review of the Significance of Popular Diets in Diabetes Mellitus Management

Diabetes mellitus is a collection of metabolic disorders marked by elevated levels of glucose in the blood due to irregularities in the generation or functioning of insulin. Medical nutrition therapy and weight loss are crucial elements in the management of diabetes and the prevention of complications. Several diets have become popular over time for the goal of achieving weight loss, but their popularity has declined due to a lack of reliable scientific evidence. This study classifies popular diets into three categories: diets that manage the composition of macronutrients, diets that restrict specific foods or food groups, and diets that manipulate meal timing. The review includes research studies that investigated the effects of popular diets on the prevention, management, and complications of diabetes. It is clear that different popular diets can have positive effects on both preventing and treating diabetes and preventing and treating complications related to diabetes. However, it is not practical to determine which diet is the most effective option for preventing or controlling diabetes. Thus, the main focus should be on common underlying factors that support well-being, such as decreasing the intake of refined grains and added sugar, choosing non-starchy vegetables, and giving priority to whole foods over processed foods whenever possible, until there is stronger evidence supporting the specific benefits of different dietary patterns.

High-protein high-konjac glucomannan diets changed glucose and lipid metabolism by modulating colonic microflora and bile acid profiles in healthy mouse models

High protein and fiber diets are becoming increasingly popular for weight loss; however, the benefits or risks of high protein and fiber diets with a normal calorie level for healthy individuals still need to be elucidated. In this study, we explored the role and mechanisms of long-term high protein and/or konjac glucomannan diets on the metabolic health of healthy mouse models. We found that high konjac glucomannan contents improved the glucose tolerance of mice and both high protein and high konjac glucomannan contents improved the serum lipid profile but increased the TNF-α levels. In the liver, high dietary protein contents reduced the expression of the FASN gene related to fatty acid synthesis. Interactions of dietary protein and fiber were shown in the signaling pathways related to lipid and glucose metabolism of the liver and the inflammatory status of the colon, wherein the high protein and high konjac glucomannan diet downregulated the expression of the SREBF1 and FXR genes in the liver and downregulated the expression of TNF-α genes in the colon compared to the high protein diet. High konjac glucomannan contents reduced the colonic secondary bile acid levels including DCA and LCA; this was largely associated with the changed microbiota profile and also contributed to improved lipid and glucose homeostasis. In conclusion, high protein diets improved lipid homeostasis and were not a risk to metabolic health, while high fiber diets improved glucose and lipid homeostasis by modulating colonic microbiota and bile acid profiles, and a high protein diet supplemented with konjac glucomannan might improve hepatic lipid homeostasis and colonic inflammation in healthy mouse models through long-term intervention.

Daily Dietary Protein Distribution Does Not Influence Changes in Body Composition During Weight Loss in Women of Reproductive Years with Overweight or Obesity: A Randomized Controlled Trial

BACKGROUND

Preservation of fat-free mass (FFM) during intentional weight loss is challenging yet important to maintain a resting metabolic rate. A balanced protein distribution of 25-30 g per meal improves 24-h muscle protein synthesis, which may promote FFM maintenance and greater reductions in fat mass (FM) during weight loss in women.

OBJECTIVES

We aimed to determine whether the daily dietary protein distribution pattern during energy restriction influences changes in body composition in women of reproductive age. We hypothesized that evenly distributing protein across meals compared with the usual intake pattern of consuming most of the protein at the dinner meal would be superior in preserving FFM while reducing FM during weight loss.

METHODS

Healthy women (n = 43) aged 20-44 y with a BMI of 28-45 kg/m2 completed a randomized parallel feeding study testing 2 patterns of daily protein intake (even distribution across all meals compared with a skewed distribution with most protein consumed at the evening meal). Participants completed an 8-wk controlled 20% energy restriction (all foods provided), followed by an 8-wk self-choice phase in which participants were asked to maintain a similar diet and dietary pattern when purchasing and consuming their own foods. Body composition was measured at baseline, week 8, and week 16. Data were analyzed using mixed models. Statistical significance was set at P < 0.05. Data are presented as differences in least squares means ± SE.

RESULTS

No significant main effects of group or group-by-time interactions were observed. All measures exhibited the main effect of time (P < 0.001). Overall, body weight, FFM, FM, and body fat percentage decreased 5.6 ± 0.4, 1.0 ± 0.2, 4.6 ± 0.4 kg, and 2.3 ± 0.2%, respectively, during this 16-wk study.

CONCLUSION

Daily dietary protein distribution at a fixed protein level does not appear to influence changes in body composition during weight loss in women of reproductive age.

CLINICAL TRIAL REGISTRY NUMBER AND WEBSITE WHERE IT WAS OBTAINED

NCT03202069 https://classic.

CLINICALTRIALS

gov/ct2/show/NCT03202069.

A systematic review of the effect of semaglutide on lean mass: insights from clinical trials

INTRODUCTION

Semaglutide, a glucagon-like peptide-1 receptor agonist, is associated with significant weight loss, yet its impact on lean body mass remains insufficiently understood. This review investigates the effect of semaglutide on lean mass in the context of obesity management.

METHODOLOGY

This study investigates through different databases (PubMed, Elsevier, and Google Scholar) from 2016 for randomized control trials (RCTs) or observational studies that assessed the use of semaglutide in overweight or obese patients, regardless of whether they have type 2 diabetes or not. The studies compared semaglutide to a placebo or alternative medications.

RESULTS

Six studies with 1,541 overweight or obese adults were included, and significant weight reductions were observed primarily due to fat mass loss. While the lean mass remained stable in some cases, notable reductions ranging from almost 0% to 40% of total weight reduction were observed in others. Noteworthy decreases in lean mass were particularly evident in larger trials, yet the proportion of lean mass relative to total body mass increased, suggesting a positive overall outcome.

CONCLUSION

Semaglutide displays potential for weight loss primarily through fat mass reduction. However, concerns arise from notable reductions in lean mass, especially in trials with a larger number of patients.

Associations between ultraprocessed and minimally processed snacks consumption and overweight/obesity among college students in South Florida

OBJECTIVE

Evaluate the association between ultraprocessed and minimally processed snack consumption and overweight/obesity among college students.

PARTICIPANTS

College students.

METHODS

Cross-sectional study. Participants completed an online survey with questions on socio-demographics, beverages and snacks consumption, and weight status. ANCOVA and logistic regression was used; analyses were adjusted for age, sex, race/ethnicity, physical activity, and sleep duration.

RESULTS

A total of 435 students completed all questions in the survey. Most students were female (73.3%), Hispanics (61.1%), had a mean age of 24.7-year old and 40% had overweight/obesity. Those with overweight/obesity also had higher odds of consuming soft drinks in higher frequency and quantity than those without overweight/obesity (p < .05). Never consuming unsweetened yogurt/cheese and lower frequency and consumption of fruits were associated with higher odds of overweight/obesity (p < .05).

CONCLUSION

Higher frequency and consumption of soft drinks while lower frequency and consumption of unsweetened yogurt/cottage cheese and fruits were associated with overweight/obesity.

Fried food consumption, genetic risk, and incident obesity: a prospective study

Background and aims: Genetic and dietary factors contribute to adiposity risk, but little evidence supports genetic personalization of fried food intake recommendations for the management of obesity. This study aimed to assess the associations between fried food consumption and adiposity incidence and whether the associations were modified by an individual's genotype. Methods: We included 27 427 participants who had dietary data assessed by a validated 24 h dietary recall and available anthropometric information from the UK Biobank study. The genetic risk score (GRS) was calculated using 940 BMI associated variants. Results: With an average of 8.1 years of follow-up, 1472 and 2893 participants were defined as having overall obesity and abdominal obesity, respectively. Individuals in the highest categories of fried food consumption were positively associated with the risk of obesity (HR = 1.31; 95% CI 1.10-1.56) and abdominal obesity (HR = 1.27; 95% CI 1.12-1.45) compared with the lowest categories. Moreover, fried food consumption had a significant interatction with obesity GRS for abdominal obesity risk (P interaction = 0.016). Fried food intake was associated with a higher abdominal obesity risk (HR = 1.59, 95% CI: 1.25-2.00) among participants with a lower genetic risk. Conclusions: Our findings indicated that fried food consumption had a higher abdominal obesity risk among individuals with a lower genetic risk, suggesting the restriction of fried food intake for this group of people.

What could be the reasons for not losing weight even after following a weight loss program?

INTRODUCTION

Approximately four million people worldwide die annually because of obesity. Weight loss is commonly recommended as a first-line therapy in overweight and obese patients. Although many individuals attempt to lose weight, not everyone achieves optimal success. Few studies point out that weight loss eventually slows down, stagnates or reverses in 85% of the cases.

RESEARCH QUESTION

What could be the reasons for not losing weight even after following a weight loss program?

METHODS

A scoping review of the literature was performed using weight loss-related search terms such as 'Obesity,' 'Overweight,' 'Lifestyle,' 'weight loss,' 'Basal Metabolism,' 'physical activity,' 'adherence,' 'energy balance,' 'Sleep' and 'adaptations. The search involved reference tracking and database and web searches (PUBMED, Science Direct, Elsevier, Web of Science and Google Scholar). Original articles and review papers on weight loss involving human participants and adults aged > 18 years were selected. Approximately 231 articles were reviewed, and 185 were included based on the inclusion criteria.

DESIGN

Scoping review.

RESULTS

In this review, the factors associated with not losing weight have broadly been divided into five categories. Studies highlighting each subfactor were critically reviewed and discussed. A wide degree of interindividual variability in weight loss is common in studies even after controlling for variables such as adherence, sex, physical activity and baseline weight. In addition to these variables, variations in factors such as previous weight loss attempts, sleep habits, meal timings and medications can play a crucial role in upregulating or downregulating the association between energy deficit and weight loss results.

CONCLUSION

This review identifies and clarifies the role of several factors that may hinder weight loss after the exploration of existing evidence. Judging the effectiveness of respective lifestyle interventions by simply observing the 'general behavior of the groups' is not always applicable in clinical practice. Each individual must be monitored and advised as per their requirements and challenges.

Microalgae: potential novel protein for sustainable human nutrition

To support a global population of ~10 billion people in 2050, dietary protein demand is forecast to increase 32-78% compared to 2017, requiring significantly higher planetary resources. Microalgae are an attractive sustainable protein source compared with current plant and animal sources. Benefits include mass scalability, low CO2 emissions, and significantly reduced land and freshwater use per unit protein. Microalgae are already used as food products and numerous species exhibit high total protein contents and well-balanced essential amino acid (EAA) compositions for human dietary requirements. Microalgae proteins are also bioavailable for human digestion, and downstream processing steps are likely to further enhance protein digestibility. Species, cultivation, and process/product optimisation are actively being developed to enhance their nutritional, social, and environmental benefits.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

Higher Imported Food Patterns Are Associated with Obesity and Severe Obesity in Tuvalu: A Latent Class Analysis

Background

Tuvalu is a Pacific Island country within the small island developing states that has observed a significant and alarming increase in obesity rates over the past 40 years, affecting ∼60 %-70 % of the current population.

Objectives

This study aimed to investigate the association between food patterns and the proportion of obesity in a Pacific Island country.

Methods

The 2022 COMmunity-based Behavior and Attitude survey in Tuvalu (COMBAT) included 985 adults with complete data on sociodemographic information and the frequency of consumption of 25 common foods. A latent class analysis determined 4 food patterns. Bayesian multilevel logistic and linear regression models estimated the association between food patterns and the proportion of obesity [body mass index (BMI) ≥30 kg/m2], severe obesity (BMI ≥40 kg/m2), and weight (kg), adjusting for potential confounders and accounting for clustering by region.

Results

The latent class analysis revealed 4 food patterns with an entropy of 0.94 and an average posterior probability of class assignment for each individual of 0.97, described as follows: 1) local: locally produced foods with moderate food diversity (proportion of individuals = 28 %); 2) diverse-local: local with greater food diversity (17 %); 3) restricted-imported: more imported with restricted diversity (29 %); and 4) imported: heavily imported with high diversity (26 %). Compared to those following the diverse-local pattern, the odds of having obesity were greater for those classified with the imported pattern [odds ratio (OR): 2.52; 95 % credible interval (CrI): 1.59, 3.99], restricted-imported pattern (OR: 1.89; 95 % CrI: 1.59, 3.99), and local pattern (OR: 1.54; 95 % CrI: 0.94, 2.50). Similar trends were observed for severe obesity while body weight was positively associated with both restricted-imported and imported food patterns.

Conclusions

The high consumption of imported foods, together with the low consumption of plant-based foods and protein-rich foods, could be a relevant modifiable lifestyle factor explaining the high levels of obesity and severe obesity in Tuvalu, a Pacific Island country.

Protein intake and body weight, fat mass and waist circumference: an umbrella review of systematic reviews for the evidence-based guideline on protein intake of the German Nutrition Society

PURPOSE

This umbrella review aimed to assess whether dietary protein intake with regard to quantitative (higher vs. lower dietary protein intake) and qualitative considerations (total, plant-based or animal-based protein intake) affects body weight (BW), fat mass (FM) and waist circumference (WC).

METHODS

A systematic literature search was conducted in PubMed, Embase and Cochrane Database of Systematic Reviews for systematic reviews (SRs) with and without meta-analyses of prospective studies published between 04 October 2007 and 04 January 2022. Methodological quality and outcome-specific certainty of evidence of the retrieved SRs were assessed by using AMSTAR 2 and NutriGrade, respectively, in order to rate the overall certainty of evidence using predefined criteria.

RESULTS

Thirty-three SRs were included in this umbrella review; 29 were based on randomised controlled trials, a few included cohort studies. In studies without energy restriction, a high-protein diet did not modulate BW, FM and WC in adults in general (all "possible" evidence); for older adults, overall certainty of evidence was "insufficient" for all parameters. Under hypoenergetic diets, a high-protein diet mostly decreased BW and FM, but evidence was "insufficient" due to low methodological quality. Evidence regarding an influence of the protein type on BW, FM and WC was "insufficient".

CONCLUSION

"Possible" evidence exists that the amount of protein does not affect BW, FM and WC in adults under isoenergetic conditions. Its impact on the reduction in BW and FM under hypoenergetic conditions remains unclear; evidence for an influence of protein type on BW, FM and WC is "insufficient".

Anorexia Nervosa With Intermittent Fever Due to Diet-Induced Thermogenesis: A Case Report

Diet-induced thermogenesis, influenced primarily by protein intake, generates energy from food. Herein, we present the case of anorexia nervosa in a 30-year-old woman, who developed intermittent fever while transitioning from continuous to intermittent tube feeding, with an increase in protein intake. Extensive investigations ruled out infection- or drug-related causes, indicating that intermittent fever resulted from diet-induced thermogenesis due to high protein administration. Recognizing the potential for diet-induced thermogenesis in cases of fever during tube feeding is crucial to avoid unnecessary antibiotic use and prevent the discontinuation of essential medications.

8. Obesity and Weight Management for the Prevention and Treatment of Type 2 Diabetes: Standards of Care in Diabetes-2024

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, an interprofessional expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Protein - a scoping review for Nordic Nutrition Recommendations 2023

Proteins are needed for providing essential amino acids, nitrogen, and fuel for the body's needs in all age groups. Proteins are especially required during active growth in pregnancy, lactation, childhood, and tissue growth in general. An adequate protein intake is needed in old adults to avoid premature muscle loss. According to the current dietary surveys, protein intake in the Nordic and Baltic countries varies from 15 to 19% of the total energy intake in adults. Comprehensive data regarding children and older adults are lacking. No good measure for protein status exists, and the estimation of physiological requirements is based on N-balance studies having some weaknesses. Protein quality is assessed by considering the protein digestibility of individual indispensable amino acids and their utilization (bioavailability), which is affected by food antinutrients and processing. The evidence regarding the association of protein intake per se with health outcomes is limited or suggestive. It is difficult to separate from the effect of other nutrients or ingredients in protein-rich foods. Proteins are widespread in foods, deriving from both animal and plant sources. Animal-sourced protein production puts more strain on the environment than plant-sourced proteins and contributes significantly to greenhouse gas emissions, thereby enhancing climate change. In Nordic and Baltic countries, consumption of animal-sourced proteins is relatively high. A shift toward more plant-based protein diets would be advisable for promoting a healthy and sustainable diet.

Chronic Thermogenic Dietary Supplement Consumption: Effects on Body Composition, Anthropometrics, and Metabolism

Multi-ingredient thermogenic supplements can acutely increase resting energy expenditure (REE) and subjective energy. However, less is understood about the effects of chronic consumption on body composition, metabolism, and subjective variables such as mood, sleep quality, and eating behaviors. Fifty-two healthy, exercise-trained participants (50% female; mean ± SD age: 23.5 ± 3.0 years; body fat percentage: 27.3 ± 8.0%) were randomized 2:2:1 to take a whey protein supplement alone (PRO; n = 20), in combination with a thermogenic supplement (PRO + FB; n = 19), or no supplement at all (CON; n = 13) for four weeks. Body composition, anthropometric, metabolic, hemodynamic, and subjective outcomes were collected before and after the intervention. Greater changes in REE occurred in PRO + FB as compared to CON (111.2 kcal/d, 95% CI 2.4 to 219.9 kcal/d, p = 0.04), without significant differences between PRO and CON (42.7 kcal/d, 95% CI -65.0 to 150.3 kcal/d, p = 0.61) or between PRO + FB and PRO (68.5 kcal/d, 95% CI -28.3, 165.3, p = 0.21). No changes in hemodynamic outcomes (blood pressure and heart rate) were observed. In exercising adults, four weeks of supplementation with protein and a multi-ingredient thermogenic product maintained fasted REE as compared to no supplementation, for which a decrease in REE was observed, without differential effects on body composition, anthropometrics, or subjective variables.

Protein and amino acids in obesity: friends or foes?

PURPOSE OF REVIEW

Nutritional interventions using protein and amino acids in obesity are popular therapeutical strategies to limit obesity development. However, the effects of dietary protein intake and amino acid metabolic alterations involved in obesity pathophysiology have not been completely unravelled. Significant recent studies have brought to light new findings in these areas, which are the primary focus of this review.

RECENT FINDINGS

We describe the effects of protein intake on weight regain prevention, the influence on gut microbiota, the response to low-protein highly processed foods, and the contrasting impacts of a high-protein diet on adults and children. We also explore newly discovered correlations between amino acids, liver fat accumulation, and the dysregulation of the liver-pancreas axis due to alterations in amino acid levels in the context of obesity. Lastly, we consider branched-chain amino acids, along with glycine and tryptophan, as significant biomarkers during periods of positive or negative energy balance.

SUMMARY

Interventions using dietary protein in obesity may be useful, especially during energy restriction but also in sarcopenic obesity. Furthermore, metabolic profiles that encompass alterations in certain amino acids can provide valuable insights into the metabolic condition of patients with obesity, particularly in relation to insulin resistance and the risk of developing type 2 diabetes.

Exploring high-protein diets in the context of cardiac rehabilitation

The review aims to explore the potential benefit and risk of high-protein diets (HPD) regarding the comorbidity of sarcopoenia and CVD in the setting of cardiac rehabilitation (CR). CR is standard care for individuals who have experienced a cardiac event, but the current practice of predominantly aerobic exercise, a lower-fat diet and weight loss poorly addresses the issue of sarcopoenia. HPD, especially when combined with resistance exercise (RE), may be valuable adjuncts to current CR practice and benefit both muscle and cardiovascular health. Meta-analyses and randomised controlled trials of HPD and CVD risk show beneficial but variable effects regarding weight loss, the lipid profile, insulin resistance and lean body mass in those living with or high risk of CVD. Meta-analyses of prospective cohort studies on hard CVD endpoints favour lower- and plant-protein diets over higher animal protein, but the evidence is inconsistent. HPD augment the strength and muscle gaining benefits of RE in older populations, but there are no published data in those living with CVD providing promising opportunities for CR research. HPD raise concern regarding renal and bone health, the microbiome, branched chain amino acids and environmental sustainability and findings suggest that plant-based HPD may confer ecological and overall health advantages compared to animal-based HPD. However, incorporating RE with HPD might alleviate certain health risks. In conclusion, a largely plant-based HPD is deemed favourable for CR when combined with RE, but further research regarding efficacy and safety in CR populations is needed.

Benefits of Chronic Administration of a Carbohydrate-Free Diet on Biochemical and Morphometric Parameters in a Rat Model of Diet-Induced Metabolic Syndrome

Carbohydrate intake restriction positively affects markers related to metabolic syndrome (MS). However, the effects of long-term carbohydrate-free diets (CFD) have yet to be studied. The main objective of this study was to report the effects on biochemical and morphometric parameters in a rat model of MS. Male Wistar rats were initially divided into two groups: the standard diet group (SD, n = 20); and the MS group (n = 30) fed a high-glucose diet. Ten animals from each group were sacrificed after 20 weeks on their respective diets to verify MS development. The remaining MS animals were divided into two subgroups: one continued with the MS diet (n = 10); and the other transitioned to a carbohydrate-free diet (MS + CFD group, n = 10) for 20 more weeks. At week 40, parameters, including glucose, insulin, lipid profile, ketone bodies, C-reactive protein (CRP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, creatinine, liver and muscle glycogen, and serum, hepatic, renal, and pancreatic malondialdehyde (MDA) levels were assessed. Transitioning to CFD resulted in decreased caloric intake and body weight, with normalized parameters including MDA, insulin, lipid profile, ALT, liver glycogen, creatinine, and CRP levels. This shift effectively reversed the MS-induced alterations, except for glycemia and uremia, likely influenced by the diet's high protein content stimulating gluconeogenesis. This research underscores the potential benefits of long-term carbohydrate restriction in mitigating MS-related markers.

Towards the characterisation of sustainable diet's gut microbiota composition and functions: A narrative review

The gut microbiome is a key element for health preservation and disease prevention. Nevertheless, defining a healthy gut microbiome is complex since it is modulated by several factors, such as host genetics, sex, age, geographical zone, drug use, and, especially, diet. Although a healthy diet has proven to increase microbial alpha and beta diversity and to promote the proliferation of health-related bacteria, considering the current environmental and nutritional crisis, such as climate change, water shortage, loss of diversity, and the obesity pandemic, it should be highlighted that a healthy diet is not always sustainable. Sustainable diets are dietary patterns that promote all dimensions of people's health and well-being while exerting low pressure on the environment, and being accessible, affordable, safe, equitable, and culturally acceptable. Examples of diets that tend to be sustainable are the Planetary Health Diet of the EAT-Lancet Commission or territorial diets such as the Mediterranean and the Traditional Mexican diet (milpa diet), adapted to specific contexts. These diets are principally plant-based but include small or moderate amounts of animal-based foods. Characterising the effects of sustainable diets on gut microbiota is urgent to ensure that the benefits for human health are aligned with environmental preservation and respect the sociocultural aspects of individuals.

The Role of Artificial Intelligence in Deciphering Diet-Disease Relationships: Case Studies

Modernization of society from a rural, hunter-gatherer setting into an urban and industrial habitat, with the associated dietary changes, has led to an increased prevalence of cardiometabolic and additional noncommunicable diseases, such as cancer, inflammatory bowel disease, and neurodegenerative and autoimmune disorders. However, while dietary sciences have been rapidly evolving to meet these challenges, validation and translation of experimental results into clinical practice remain limited for multiple reasons, including inherent ethnic, gender, and cultural interindividual variability, among other methodological, dietary reporting-related, and analytical issues. Recently, large clinical cohorts with artificial intelligence analytics have introduced new precision and personalized nutrition concepts that enable one to successfully bridge these gaps in a real-life setting. In this review, we highlight selected examples of case studies at the intersection between diet-disease research and artificial intelligence. We discuss their potential and challenges and offer an outlook toward the transformation of dietary sciences into individualized clinical translation.

A Study on the Amelioration of Circadian Rhythm Disorders in Fat Mice Using High-Protein Diets

This innovative study investigates the effects of high-protein diets (milk protein) on the circadian rhythm of hepatic lipid metabolism. We aimed to understand how high-protein interventions regulate biological clock genes, maintain lipid metabolism balance, and affect the circadian rhythm of antioxidant levels in vivo. We divided 120 SPF-class C57BL/6J mice into the control, high-fat/low-protein (HF-LP), and high-fat/high-protein (HF-HP) groups. Mice were sacrificed during active (2 a.m. and 8 a.m.) and rest periods (2 p.m. and 8 p.m.). In the HF-LP group, hepatic lipid anabolic enzymes were consistently expressed at high levels, while key lipolytic enzymes slowly increased after feeding with no significant diurnal differences. This led to an abnormal elevation in blood lipid levels, a slow increase in and low levels of superoxide dismutase, and a rapid increase in malondialdehyde levels, deviating from the diurnal trend observed in the control group. However, high-protein interventions in the HF-HP group restored lipid synthase activity and the expression of key catabolic enzymes, exhibiting a precise circadian rhythm. It also improved the lipid-metabolism rhythm, which was disrupted by the high-fat diet. Overall, high-protein interventions restored the expression of key enzymes involved in lipid metabolism, improving the lipid-metabolism rhythm, which was disrupted by the high-fat diet.

Effects of 12 weeks of low molecular collagen peptide supplementation on body composition in overweight Korean adults aged 50 years and older.. [DOI: 10.21203/rs.3.rs-3016558/v2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

After the age of 50, their muscle mass gradually declines each year, and the lost muscle is often replaced by fat mass. Insufficient protein intake after middle age further accelerates this process. Previous studies that have used collagen as a supplementation, which accounts for about 30% of the body's protein, have combined it with resistance exercise. This study investigated the effects of collagen supplementation on body composition in individuals over the age of 50 (23≤BMI≤32), while maintaining their daily activity levels constant. Participants were assigned to either the collagen group (n=42) or the placebo group(n=42). Collagen supplementation (15g of collagen) and placebo product (xanthan gum) were offered. Bioactive Collagen Peptides, which is a type of low molecular weight collagen extracted from porcine raw materials, was used. Body composition was measured by bioelectrical impedance analysis and dual-energy X-ray absorptiometry. Blood samples were taken for analysis. Physical activities and dietary intake were measured by international physical activity questionnaire and a 3-day food record, respectively. 74 participants in the collagen group (n=37) and placebo group (n=37) were used in the final analysis. Physical activity and dietary intake showed no significant difference between the two groups. The collagen group showed a significant reduction in total body fat mass compared to the placebo group, as evidenced by both BIA (P=0.021) and DEXA (P=0.041) measurements. There were no significant differences in blood measurements between the two groups. Therefore, the intake of collagen supplementation after middle age may be used for preventing age related fat mass accumulation.

The PCOS puzzle: putting the pieces together for optimal care

Polycystic ovary syndrome (PCOS) is a multifaceted hormonal disorder that has significant ramifications for both women's reproductive and metabolic well-being. This analysis aims to offer a thorough comprehension of PCOS by investigating the various contributing factors that are crucial for its effective management. We delve into the topic of hormonal imbalances, such as elevated androgens and disrupted estrogen-progesterone dynamics, and their effects on reproductive and metabolic health. Furthermore, we explore the intricate connection between insulin resistance, hyperinsulinemia, and PCOS, highlighting their pivotal role in metabolic dysfunction. Additionally, we examine fertility challenges, irregular menstrual patterns, and metabolic complications while also reviewing current treatment methodologies. Moreover, we address the latest research concerning genetic, environmental, and epigenetic influences on PCOS. By piecing together these essential elements, healthcare professionals can attain a comprehensive understanding of PCOS and deliver optimal care for those affected by the condition.

Obesity management in the Saudi population

Obesity is an alarming public health concern and needs to be addressed promptly in the Kingdom of Saudi Arabia. Sedentary lifestyle, changes in dietary intake and choice, culture, gender, climatic conditions and, lately, COVID-19 have contributed to obesity as a near epidemic in the Kingdom of Saudi Arabia. Interventions targeting obesity includes lifestyle management, pharmacotherapy, and surgery. Lifestyle interventions qualify as first-line therapies. Diets include a low-fat diet, low-calorie diet, low-carbohydrate diet, high-protein diet, and low-glycemic-index diet. Diet and exercise interventions can have a huge impact on weight loss. Pharmacotherapy is considered a treatment option at a later stage. Surgery is only for severely obese individuals. Above all, the government has to intervene and implement regulations and policies that can curb the incidence of obesity. This review aims to address obesity in the Kingdom of Saudi Arabia, interventions to curb it, and the impact of COVID-19 on obesity.

Effects of collagen supplementation on body composition and muscle strength in Korean adults aged 50 years and older.. [DOI: 10.21203/rs.3.rs-3016558/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

BACKGROUND: Insufficient protein intake can accelerate the loss of muscle mass as one ages. A decrease in muscle mass leads to an increase in fat mass, creating a vicious cycle that can result in sarcopenic obesity. Previous studies that have used collagen as a supplementation, which accounts for about 30% of the body's protein, have combined it with resistance exercise. OBJECTIVE: This study investigated the effects of collagen supplementation on body composition in individuals over the age of 50, while maintaining their daily activity levels constant. DESIGN: Double-blind randomized controlled trial PARTICIPANTS: Participants were assigned to either the collagen group (n=42) or the placebo group(n=42). MEASUREMENTS: Collagen supplementation (14g of collagen) and placebo product (xanthan gum) were offered to collagen group and placebo group respectively, once a day. Body composition was measured by bioelectrical impedance analysis and dual-energy X-ray absorptiometry. Participants were instructed to maintain their dietary intake and physical activity levels, which were evaluated through a 3-day food record analysis and an international physical activity questionnaire (IPAQ) analysis, respectively. RESULTS: 74 participants in the collagen group (n=37) and placebo group (n=37) completed the follow-up, and there was no significant difference between the two groups in terms of physical activity levels. The collagen group showed a significant reduction in total body fat mass compared to the placebo group, as evidenced by both BIA (P=0.021) and DEXA (P=0.041) measurements. However, there was no significant difference between the two groups in terms of muscle mass. Conclusion: From this study, the consumption of collagen supplementation is effective in reducing fat mass, which is significant in preventing sarcopenic obesity after middle age.

Effects of Animal and Vegetable Proteins on Gut Microbiota in Subjects with Overweight or Obesity

The gut microbiota plays a pivotal role in the balance between host health and obesity. The composition of the gut microbiota can be influenced by external factors, among which diet plays a key role. As the source of dietary protein is important to achieve weight loss and gut microbiota modulation, in the literature there is increasing evidence to suggest consuming more plant proteins than animal proteins. In this review, a literature search of clinical trials published until February 2023 was conducted to examine the effect of different macronutrients and dietary patterns on the gut microbiota in subjects with overweight and obesity. Several studies have shown that a higher intake of animal protein, as well as the Western diet, can lead to a decrease in beneficial gut bacteria and an increase in harmful ones typical of obesity. On the other hand, diets rich in plant proteins, such as the Mediterranean diet, lead to a significant increase in anti-inflammatory butyrate-producing bacteria, bacterial diversity and a reduction in pro-inflammatory bacteria. Therefore, since diets rich in fiber, plant protein, and an adequate amount of unsaturated fat may help to beneficially modulate the gut microbiota involved in weight loss, further studies are needed.

Effects of Poria cocos extract and protein powder mixture on glucolipid metabolism and rhythm changes in obese mice

Herein, we explored the effects of Poria cocos extract, protein powder mixture, and their combined intervention on weight loss in high-fat diet (HFD)-induced obese mice. Male C57BL/6J mice were selected and fed a HFD for 8 weeks; obese mice that were successfully modeled were divided into modeling and five intervention groups, and given the corresponding treatment for 10 weeks. Body weight, fat, and muscle tissue, blood glucose, lipids, inflammatory factors, and other glucose and lipid metabolism-related indicators were measured to evaluate the effect of P. cocos and protein powder intervention on weight loss in obese mice. The body weight of the intervention group was reduced compared with the HFD group. Fat content of mice in F3PM group decreased significantly (p < .05). Levels of blood glucose, lipids, adiponectin, leptin, and inflammatory factors, including interleukin-1 β and tumor necrosis factor- α showed improvement. Lipoprotein lipase (lower about 2.97 pg/ml, vs. HFD mice 10.65 mmoL/ml) and sterol regulatory element-binding transcription factor (lower about 1413.63 pg/ml, vs. HFD mice 3915.33 pg/ml) levels in liver tissue were decreased. The respiratory exchange rate (RER) of mice in the HFD and subject intervention groups had no circadian rhythm and was maintained at approximately 0.80. The protein powder mixture (PM) group had the lowest RER (p < .05), the P. cocos extract (FL) and F1PM groups had similar RER to the HFD group (p < .05), and the F2PM group had a higher RER than the HFD group (p < .05). And food intake and energy metabolism returned to circadian rhythm, with an increase in the dose of P. cocos extract, the feeding rhythms of F1PM, F2PM, and F3PM were closer to that of the normal diet (ND) group. Feeding intervention with P. cocos and protein powder improved fat distribution, glucolipid metabolism, and energy metabolism, with the combination of F3PM showing more diverse benefits.