Energy-restricted Diet Research Articles

Relationship between Ketones, Ghrelin, and, Appetite on Isocaloric Diets with Varying Carbohydrate Quality and Amount: Results from a Randomized Controlled Trial in People with Obesity (CARBFUNC)

BackgroundLow-carbohydrate high-fat (LCHF) diets may suppress the increase in appetite otherwise seen after diet-induced fat loss. However, studies of diets without severe energy restriction are lacking, and the effects of carbohydrate quality relative to quantity have not been directly compared. ObjectivesTo evaluated short- (3 mo) and long-term (12 mo) changes in fasting plasma concentrations of total ghrelin, β-hydroxybutyrate (βHB), and subjective feelings of appetite on 3 isocaloric eating patterns within a moderate caloric range (2000–2500 kcal/d) and with varying carbohydrate quality or quantity. MethodsWe performed a randomized controlled trial of 193 adults with obesity, comparing eating patterns based on “acellular” carbohydrate sources (e.g., flour-based whole-grain products; comparator arm), “cellular” carbohydrate sources (minimally processed foods with intact cellular structures), or LCHF principles. Outcomes were compared by an intention-to-treat analysis using constrained linear mixed modeling. This trial was registered at clinicaltrials.gov as NCT03401970. ResultsOf the 193 adults, 118 (61%) and 57 (30%) completed 3 and 12 mo of follow-up. Throughout the intervention, intakes of protein and energy were similar with all 3 eating patterns, with comparable reductions in body weight (5%−7%) and visceral fat volume (12%−17%) after 12 mo. After 3 mo, ghrelin increased significantly with the acellular (mean: 46 pg/mL; 95% CI: 11, 81) and cellular (mean: 54 pg/mL; 95% CI: 21, 88) diets but not with the LCHF diet (mean: 11 pg/mL; 95% CI: −16, 38). Although βHB increased significantly more with the LCHF diet than with the acellular diet after 3 m (mean: 0.16 mmol/L; 95% CI: 0.09, 0.24), this did not correspond to a significant group difference in ghrelin (unless the 2 high-carbohydrate groups were combined [mean: −39.6 pg/mL; 95% CI: −76, −3.3]). No significant between-group differences were seen in feelings of hunger. ConclusionsModestly energy-restricted isocaloric diets differing in carbohydrate cellularity and amount showed no significant differences in fasting total ghrelin or subjective hunger feelings. An increase in ketones with the LCHF diet to 0.3–0.4 mmol/L was insufficient to substantially curb increases in fasting ghrelin during fat loss.

Differential effects of bariatric surgery and lifestyle interventions on plasma levels of Lp(a) and fatty acids

BackgroundLimited evidence suggests that surgical and non-surgical obesity treatment differentially influence plasma Lipoprotein (a) [Lp(a)] levels. Further, a novel association between plasma arachidonic acid and Lp(a) has recently been shown, suggesting that fatty acids are a possible target to influence Lp(a). Here, the effects of bariatric surgery and lifestyle interventions on plasma levels of Lp(a) were compared, and it was examined whether the effects were mediated by changes in plasma fatty acid (FA) levels.MethodsThe study includes two independent trials of patients with overweight or obesity. Trial 1: Two-armed intervention study including 82 patients who underwent a 7-week low energy diet (LED), followed by Roux-en-Y gastric bypass and 52-week follow-up (surgery-group), and 77 patients who underwent a 59-week energy restricted diet- and exercise-program (lifestyle-group). Trial 2: A clinical study including 134 patients who underwent a 20-week very-LED/LED (lifestyle-cohort).ResultsIn the surgery-group, Lp(a) levels [median (interquartile range)] tended to increase in the pre-surgical LED-phase [17(7–68)-21(7–81)nmol/L, P = 0.05], but decreased by 48% after surgery [21(7–81)—11(7–56)nmol/L, P < 0.001]. In the lifestyle-group and lifestyle-cohort, Lp(a) increased by 36%[14(7–77)—19(7–94)nmol/L, P < 0.001] and 14%[50(14–160)—57(19–208)nmol/L, P < 0.001], respectively. Changes in Lp(a) were independent of weight loss. Plasma levels of total saturated FAs remained unchanged after surgery, but decreased after lifestyle interventions. Arachidonic acid and total n-3 FAs decreased after surgery, but increased after lifestyle interventions. Plasma FAs did not mediate the effects on Lp(a).ConclusionBariatric surgery reduced, whereas lifestyle interventions increased plasma Lp(a), independent of weight loss. The interventions differentially influenced changes in plasma FAs, but these changes did not mediate changes in Lp(a).Trial registrationTrial 1: Clinicaltrials.gov NCT00626964.Trial 2: Netherlands Trial Register NL2140 (NTR2264).Graphical abstract

Avaliação da ocorrência de síndrome metabólica em cães obesos e o papel da dieta de restrição calórica como uma terapia adjuvante

Metabolic syndrome, or metabolic dysfunction related to obesity in dogs, is a set of factors that may predispose comorbidities secondary to obesity. Adjuvant therapy with an energy-restricted diet, especially with low levels of carbohydrate and fat, is essential for weight loss, in addition to controlling snacks intake. The aim of this study was to evaluate the biochemical profile of obese dogs compared to lean dogs, and also to compare these profiles before and after a 30-day treatment, thus evaluating the possibility of obesity-related metabolic dysfunction and the action of adjuvant dietary therapy in this condition. Cholesterol and its fractions (HDL, LDL and VLDL), triglycerides, systemic blood pressure and glycemia of obese and lean dogs were measured, and seven obese dogs were treated only with a low-calorie diet with low levels of fat and carbohydrates for 30 days; these patients were evaluated before and after treatment. Obese dogs showed higher levels of triglycerides than lean dogs, and dogs treated with low-calorie diet presented weight loss and better outcomes related to biochemical profile, especially triglycerides levels, after treatment.

The Interplay of Sirtuin-1, LDL-Cholesterol, and HDL Function: A Randomized Controlled Trial Comparing the Effects of Energy Restriction and Atorvastatin on Women with Premature Coronary Artery Disease.

HDL function has gained prominence in the literature as there is a greater predictive capacity for risk in early coronary artery disease when compared to the traditional parameters. However, it is unclear how dietary energy restriction and atorvastatin influence HDL function. A randomized controlled trial with 39 women with early CAD divided into three groups (n = 13): energy restriction (30% of VET), atorvastatin (80 mg), and control. Analyses of traditional biochemical markers (lipid and glucose profile), circulating Sirt-1, and HDL function (lipid composition, lipid transfer, and antioxidant capacity). Participants' mean age was 50.5 ± 3.8 years. Energy restriction increased Sirt-1 by 63.6 pg/mL (95%CI: 1.5-125.7; p = 0.045) and reduced BMI by 0.8 kg/m2 (95%CI: -1.349--0.273; p = 0.004) in a manner independent of other cardiometabolic factors. Atorvastatin reduced LDL-c by 40.0 mg/dL (95%CI: -69.910--10.1; p = 0.010). Increased Sirt-1 and reduced BMI were independently associated with reduced phospholipid composition of HDL (respectively, β = -0.071; CI95%:-0.136--0.006; p = 0.033; β = 7.486; CI95%:0.350-14.622; p = 0.040). Reduction in BMI was associated with lower HDL-free cholesterol (β = 0.818; CI95%:0.044-1.593; p = 0.039). LDL-c reduction by statins was associated with reduced maximal lipid peroxide production rate of HDL (β = 0.002; CI95%:0.000-0.003; p = 0.022) and total conjugated diene generation (β = 0.001; CI95%:0.000-0.001; p = 0.029). This study showed that energy restriction and atorvastatin administration were associated with changes in lipid profile, serum Sirt-1 concentrations, and HDL function.

Plasma FGF21 Levels Are Not Associated with Weight Loss or Improvements in Metabolic Health Markers upon 12 Weeks of Energy Restriction: Secondary Analysis of an RCT.

Recent studies suggest that circulating fibroblast growth factor 21 (FGF21) may be a marker of metabolic health status. We performed a secondary analysis of a 12-week randomized controlled trial to investigate the effects of two energy restriction (ER) diets on fasting and postprandial plasma FGF21 levels, as well as to explore correlations of plasma FGF21 with metabolic health markers, (macro)nutrient intake and sweet-taste preference. Abdominally obese subjects aged 40-70 years (n = 110) were randomized to one of two 25% ER diets (high-nutrient-quality diet or low-nutrient-quality diet) or a control group. Plasma FGF21 was measured in the fasting state and 120 min after a mixed meal. Both ER diets did not affect fasting or postprandial plasma FGF21 levels despite weight loss and accompanying health improvements. At baseline, the postprandial FGF21 response was inversely correlated to fasting plasma glucose (ρ = -0.24, p = 0.020) and insulin (ρ = -0.32, p = 0.001), HOMA-IR (ρ = -0.34, p = 0.001), visceral adipose tissue (ρ = -0.24, p = 0.046), and the liver enzyme aspartate aminotransferase (ρ = -0.23, p = 0.021). Diet-induced changes in these markers did not correlate to changes in plasma FGF21 levels upon intervention. Baseline higher habitual polysaccharide intake, but not mono- and disaccharide intake or sweet-taste preference, was related to lower fasting plasma FGF21 (p = 0.022). In conclusion, we found no clear evidence that fasting plasma FGF21 is a marker for metabolic health status. Circulating FGF21 dynamics in response to an acute nutritional challenge may reflect metabolic health status better than fasting levels.

Effects of protein intake from an energy-restricted diet on the skeletal muscle composition of overweight and obese rats

Excess weight and obesity are often associated with ectopic adipose tissue accumulation in skeletal muscles. Intermuscular adipose tissue (IMAT) impairs muscle quality and reduces insulin-stimulated skeletal muscle glucose uptake. Although energy restriction and high protein intake can decrease IMAT, the effects and mechanisms of protein intake from an energy-restricted diet on protein and fat masses in skeletal muscle have received little attention. After establishing a diet-induced overweight and obese Sprague-Dawley rat model (half male and half female), rats were divided into five groups: normal control (NC; normal weight, general maintenance diet), model control (MC; overweight and obesity, high-fat diet), energy-restricted low protein (LP; overweight and obesity, 60% energy intake of NC, general maintenance diet), energy-restricted normal protein (NP; overweight and obesity, 60% energy intake of NC, high-protein diet 1), and energy-restricted high protein (HP; overweight and obesity, 60% energy intake of NC, high-protein diet 2). After 8 weeks, plasma and skeletal muscle (quadriceps femoris and gastrocnemius) samples were collected. Plasma levels of glucose, triglycerides, and hormones were analyzed, while contents of protein, fat, and factors associated with their synthesis and degradation were evaluated in skeletal muscles. Plasma concentrations of hormones contrasted protein and fat contents in skeletal muscles. Fat weights and contents of quadriceps femoris and gastrocnemius muscles in the NP group were significantly lower compared with LP and HP groups (P < 0.05). Moreover, concentrations of factors associated with the degradation of muscle fat were significantly higher in the NP group compared with LP and HP groups (P < 0.05). During energy restriction, protein intake equal to that of a normal protein diet increased lipolysis of quadriceps femoris and gastrocnemius muscles in rats of both sexes.

Nut-enriched energy restricted diet has potential to decrease hunger in women at cardiometabolic risk: a randomized controlled trial (Brazilian Nuts Study)

Successful weight management represents a challenge to obesity control. Evidence suggests that nut consumption promotes a prolonged satiety response. Therefore, we hypothesize that nuts could be associated with greater weight loss in comparison to a control group, and we evaluate the acute and long-term effects of Brazilian nuts (BN: 15 g of Brazil nuts+30 g of cashew nuts) included in an energy-restricted intervention on food intake, appetite, and peptide hormones. We conducted an 8-week, randomized, open-label, controlled, parallel-arm clinical trial with 28 women at cardiometabolic risk who received an energy-restricted diet containing BN or an energy-restricted nut-free diet (control). At baseline and after 8 weeks of intervention, subjective postprandial appetite ratings were assessed using a visual analog scale (VAS) before and after consumption (0, 10, 60, 120, 180, and 240 minutes) of a 437-kcal nut-enriched (BN group) or nut-free (control) breakfast meal. Subsequently, an ad libitum lunch was served, and the participants completed another VAS at 280 minutes. Plasma concentrations of ghrelin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and leptin were measured at fasting and postprandially at 60, 120, and 240 minutes. Last, subsequent reported 24-hour energy intake was assessed in a free-living setting. BN consumption did not have acute effects on food intake, appetite, or peptide hormones. However, after an 8-week intervention, postprandial ghrelin (difference between post- and preintervention area under the curve) decreased in the BN group in comparison to the control (mean difference, 1978 pg/mL/min, 95% CI, 27-3929 pg/mL/min; P=.047) and therefore, an energy-restricted diet containing demonstrated potential to decrease hunger in cardiometabolic risk women.

Reduced brain activity during a working memory task in middle-aged apolipoprotein E ε4 carriers with overweight/obesity.

The apolipoprotein E ε4 (APOE ε4) allele and midlife obesity are independent risk factors for Alzheimer's disease (AD). Both of these risk factors are also associated with differences in brain activation, as measured by blood oxygenation level-dependent (BOLD) responses, in the absence of detectable cognitive deficits. Although the presence of these risk factors may influence brain activity during working memory tasks, no study to date has examined whether the presence of the ε4 allele explains variation in working memory brain activity while matching for levels of overweight/obesity. The primary aim of this study was to determine whether the presence of the ε4 allele is associated with differences in task-functional magnetic resonance imaging (fMRI) brain activation in adults with overweight/obesity. We predicted that ε4 carriers would have greater brain activation in regions that support working memory. This ancillary study included 48 (n = 24 APOE ε4 carriers; n = 24 APOE ε4 non-carriers), sedentary middle-aged adults (Mean age = 44.63 ± 8.36 years) with overweight/obesity (Mean BMI = 32.43 ± 4.12 kg/m2) who were matched on demographic characteristics. Participants were a subsample enrolled in 12-month randomized clinical trial examining the impact of energy-restricted diet and exercise on cardiovascular health outcomes. Participants completed a n-back working memory task with fMRI, which were completed within one month of the start of the intervention. Participants also underwent pseudo-continuous arterial spin labeling scans, a MRI measure of cerebral blood flow (CBF). Compared to non-ε4 carriers with overweight/obesity, ε4 carriers with overweight/obesity had lower fMRI brain activity in the middle frontal gyrus, pre and post central gyrus, supramarginal gyrus, superior temporal gyrus, lateral occipital cortex, and angular gyrus (z range = 2.52-3.56) during the n-back working memory task. Differences persisted even when controlling for CBF in these brain regions. These results indicate that presence of the APOE ε4 allele in middle-aged adults with overweight/obesity is related to altered brain activity during a working memory paradigm, which may confer risk for accelerated neurocognitive decline in late adulthood. Future research is needed to clarify the clinical implications of these findings in the context of risk for AD.

Mental health and quality of life during weight loss in females with clinically severe obesity: a randomized clinical trial.

The purpose of this investigation was to explore the effects of dietary weight loss intervention, with and without the addition of exercise on health-related quality of life, depressive symptoms, and anxiety. As part of the EMPOWER study for women, sixty premenopausal women (BMI of 40.4 ± 6.7) were randomized to energy restriction only (ER) or to exercise plus energy restriction (EXER) for 12months. Health-related quality of life was assessed using the SF-36, depressive symptoms were assessed using the Beck Depression Inventory II (BDI), and anxiety symptoms using the Spielberger state and trait anxiety questionnaire. All measures were completed at baseline, 3, 6 and 12months. At 12months, there were significant (p < 0.05) group-by-time interactions favouring the EXER group for five of the eight domains and the mental component summary score. At 12months, a significant group-by-time interaction favouring the EXER group is reported for both state and trait anxiety (p = .005 and p = .001, respectively). At 12months, there was a significant group-by-time interaction for depressive symptoms favouring EXER (p < 0.05). Within-group changes for BDI scores were improved at all follow-up time points in the EXER group. Exercise training confers an additional benefit to energy restriction in the absence of additional weight loss at 12months for health-related quality of life, depressive symptoms, and state and trait anxiety scores when compared to energy restriction only. Exercise and an energy-restricted diet improve health-related quality of life and mental health. Exercise may protect mental health without further weight loss for women with severe obesity.

Dietary energy restriction inneurologicaldiseases: what's new?

Energy-restricted diet is a specific dietary regimen, including the continuous energy-restricted diet and the intermittent energy-restricted diet. It has been proven effective not only to reduce weight and extend the lifespan in animal models, but also to regulate the development and progression of various neurological diseases such as epilepsy, cerebrovascular diseases (stroke), neurodegenerative disorders (Alzheimer's disease and Parkinson's disease) and autoimmune diseases (multiple sclerosis). However, the mechanism in this field is still not clear and a systematic neurological summary is still missing. In this review, we first give a brief summary of the definition and mainstream strategies of energy restrictions. We then review evidence about the effects of energy-restricted diet from both animal models and human trials, and update the current understanding of mechanisms underlying the biological role of energy-restricted diet in the fight against neurological diseases. Our review thus contributes to the modification of dietary regimen and the search for special diet mimics.

An Energy-Restricted Diet Including Yogurt, Fruit, and Vegetables Alleviates High-Fat Diet–Induced Metabolic Syndrome in Mice by Modulating the Gut Microbiota

The importance of the composition of an energy-restricted diet in the treatment of metabolic syndrome (MetS) is unknown. In this study we aimed to investigate the benefits of a novel dietary treatment (50% calorie restriction diet composed of yogurt, fruit, and vegetables [CR-YD]) in mice with MetS. Forty 7-wk-old male C57BL/6 J mice were randomly assigned to 4 groups (n = 10/group) that were fed for 14 wk ad libitum with a normal diet (ND; 10%:70%:20% energy from fat: carbohydrate: protein) or for 12 wk with a high-fat diet (HFD; 60:20:20) or the HFD followed by 2 wk of feeding with a 50% calorie-restricted HFD (CR-HFD) or YD (CR-YD, 21.2%:65.4%:13.4% energy). Body weight, fat deposition, hepatic steatosis, serum concentrations of inflammatory biomarkers, and glucose homeostasis were assessed. Fecal microbiota transplantation (FMT) was used to validate the roles of gut microbiota in MetS. The HFD group had 50% greater body weight and 475% greater fat deposition than the ND group (P < 0.05). Compared with the HFD group, the CR-HFD and CR-YD groups had 22% and 31% lower body weight and 49% and 75% less fat deposition, respectively (P < 0.05). Compared with the CR-HFD group, the CR-YD group had 11% lower body weight, 96% less fat deposition, 500% less hepatic steatosis, 75% lower glucose, and 450% more hepatic Akkermansia bacteria (P < 0.05). The CR-YD group also had 50% lower histopathology scores and 1.35-fold higher levels of Claudin4 than the CR-HFD group (P < 0.05). The HFD + CR-YD fecal group had 10.6% lower body weight, 119% lower steatosis, and 17.9% lower glucose (P < 0.05) than the HFD + CR-HFD fecal group. Compared with CR alone, the CR-YD diet has a better therapeutic effect in mice with HFD-induced MetS.

Are the Modern Diets for the Treatment of Obesity Better than the Classical Ones?

Conventional hypocaloric diets, providing continuous energy restriction, are considered to be the cornerstone of dietary management of obesity. Although energy-restricted diets are overall safe, healthy, and modestly effective, their long-term adherence is difficult to accomplish. Intermittent fasting and ketogenic diets have emerged as attractive alternative dietary options for weight loss and improvement in cardiometabolic risk. Intermittent fasting is a unique dietary pattern characterized by periods of eating alternated with periods of fasting. Ketogenic diets are very low in carbohydrate, modest in protein, and high in fat. Several systematic reviews and meta-analyses of randomized controlled trials (RCTs) have reported beneficial but short-lived effects of intermittent fasting and ketogenic diets on various obesity-related health outcomes. Although for both diets, the current evidence is promising and steadily evolving, whether they are better than traditional calorie-restricted diets, whether they can safely lead to sustained weight loss and overall health benefits, and their effects on body composition, weight loss maintenance, energy intake and expenditure, diet quality, and cardiometabolic risk factors are still not unequivocally proven. The aim of the present review is to summarize the current state of evidence regarding the effects of these two popular modern diets, namely intermittent fasting and ketogenic diets. We describe the rationale and characteristics of different dietary protocols, we analyze the major mechanisms explaining their weight loss and cardiometabolic effects, and we provide a concise update on their effects on body weight and cardiometabolic risk factors, focusing on meta-analyses of RCTs. We also discuss knowledge gaps in the field of these diets, and we indicate directions for future research.

A Comparative Study of the Anti-Obesity Effects of Dietary Sea Cucumber Saponins and Energy Restriction in Response to Weight Loss and Weight Regain in Mice.

Dietary supplementation of sea cucumber saponins and calorie restriction have been proved to be effective in alleviating obesity, but the differences of anti-obesity effects between sea cucumber saponins and energy restriction during weight loss and weight regain are still unknown. In the present study, high-fat-induced obesity mice were randomly divided into three groups, including a high-fat diet group (HF), an energy restriction by 40% group (HF-L), and a sea cucumber saponins group (HF-S), to compare the effects of dietary sea cucumber saponins and energy restriction on the weight, glucose, and lipid metabolism of obese mice during weight loss and weight regain. The results showed that dietary 0.06% sea cucumber saponins and limiting energy intake by 40% had the same weight loss effect. Interestingly, sea cucumber saponins could alleviate impaired glucose tolerance and insulin resistance caused by obesity. In addition, the inhibited SREBP-1c mediated lipogenesis might lead to the alleviation of weight regain after resuming the high-fat diet even when sea cucumber saponins were no longer supplemented. In contrast, limiting energy intake tended to promote lipid synthesis in the liver and white adipose tissue after restoring a high-fat diet, and inflammation was also induced. The findings indicated that sea cucumber saponins could replace calorie restriction to prevent obesity and might be used as a functional food or drug to resist obesity and related diseases caused by obesity.

Dietary Energy Intake and Presence of Aberrant Crypt Foci Are Associated with Phospholipid, Purine, and Taurine Metabolite Abundances in C57BL/6N Mouse Colon.

Colon metabolomes associated with high-fat (H) versus energy-restricted (E) diets in early colorectal cancer (CRC) models have never been directly compared. The objectives of this study are to elucidate metabolites associated with diet, aberrant crypt foci (ACF), and diet:ACF interaction, using a lifetime murine model. Three-week-old mice consumed control (C), E, or H initiation diets for 18 weeks. ACF formation is initiated weeks 16-21 with azoxymethane injections, followed by progression diet crossover (to C, E, or H) through week 60. Colon extracts are analyzed using ultra-high-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Metabolites associated with diet, ACF, or diet:ACF are determined using regression models (FDR-adjusted p-value &lt;0.05). No metabolites are significantly associated with initiation diets, but concentrations of acylcarnitines and phospholipids are associated with C, E, and H progression diets. Purines, taurine, and phospholipids are associated with ACF presence. No significant associations between metabolites and diet:ACF interaction are observed. These results suggest that recent, rather than early-life, diet is more closely associated with the colon metabolome, particularly lipid metabolism. Results from this study also provide candidate biomarkers of early CRC development and provide support for the importance of early diet on influencing pre-CRC risk.

Research progress on the relationship between dietary patterns and metabolic-associated fatty liver disease

Globally, metabolic-asssociated fatty liver disease has become a significant health burden due to its complex pathogenesis, and there are no specific and effective therapeutic drugs to date. The onset and progression of metabolic-asssociated fatty liver disease is closely associated with improper dietary habits. The cornerstone to treat metabolic-asssociated fatty liver disease is weight loss through a well-balanced diet. This article summarizes and discusses the research progress at home and abroad in relationship to metabolic-asssociated fatty liver disease and dietary patterns such as the Mediterranean diet, the DASH diet, an energy-restricted balanced diet, a low fat diet, a low carbohydrate diet, a western diet, an animal food diet, a traditional diet, and others. In addition, it categorizes the effects of various dietary patterns on the prevention, treatment, or induction of several issues that need further metabolic-asssociated fatty liver disease research for subsequent reference.

Changes in Novel Anthropometric Indices of Abdominal Obesity during Weight Loss with Selected Obesity-Associated Single-Nucleotide Polymorphisms: A Small One-Year Pilot Study.

Whether BMI and the competing waist circumference (WC)-based anthropometric indices are associated with obesity-related single-nucleotide polymorphisms (SNPs) is as yet unknown. The current study aimed to evaluate the anthropometric indices (fat mass index, body shape index, visceral adiposity index, relative fat mass, body roundness index, and conicity index) during a weight loss intervention in 36 obese individuals. Blood biochemical parameters (total cholesterol, low-density lipoprotein, high-density lipoprotein, and triglycerides) and three SNPs (FTO rs9939609, TFAP2B rs987237, and PLIN1 rs894160) were assessed in 22 women and 14 men (35.58 ± 9.85 years, BMI 35.04 ± 3.80 kg/m2) who completed a 12-month balanced energy-restricted diet weight loss program. Body composition was assessed via bioelectrical impedance (SECA mBCA515). At the end of the weight loss intervention, all anthropometric indices were significantly reduced (p < 0.05). For the SNP FTO rs9939609, the higher risk allele (A) was characteristic of 88.9% of the study group, in which 10 participants (27.8%) were homozygous. We found a similar distribution of alleles in TFAP2B and PLIN1. Heterozygous genotypes in FTO rs9939609 and TFAP2B rs987237 were predisposed to significant reductions in WC-based novel anthropometric indices during weight loss. The influence of PLIN1 rs894160 polymorphisms on the changes in the analyzed indices during weight loss has not been documented in the present study.

Are methods of estimating fat-free mass loss with energy-restricted diets accurate?

Fat-free mass (FFM) often serves as a body composition outcome variable in weight loss studies. An important assumption is that the proportions of components that make up FFM remain stable following weight loss; some body composition models rely on these "constants". This exploratory study examined key FFM component proportions before and following weight loss in two studies of participants with overweight and obesity. 201 men and women consumed calorie-restricted moderate- or very-low carbohydrate diets leading to 10-18% weight loss in 9-15 weeks. Measured total body fat, lean mass, bone mineral, total body water (TBW), and body weight at baseline and follow-up were used to derive FFM and its chemical proportions using a four-component model. A consistent finding in both studies was a non-significant reduction in bone mineral and a corresponding increase (p < 0.001) in bone mineral/FFM; FFM density increased significantly in one group of women and in all four participant groups combined (both, p < 0.05). FFM hydration (TBW/FFM) increased in all groups of men and women, one significantly (p < 0.01), and in the combined sample (borderline, p < 0.10). The proportion of FFM as protein decreased across all groups, two significantly (p < 0.05-0.01) and in the combined sample (p < 0.05). FFM relative proportions of chemical components may not be identical before and after short-term weight loss, an observation impacting some widely used body composition models and methods. Caution is thus needed when applying FFM as a safety signal or to index metabolic evaluations in clinical trials when these body composition approaches are used.

The impact of dieting culture is different between sexes in endurance athletes: a cross-sectional analysis

BackgroundFrequent dieting is common in athletes attempting to achieve a body composition perceived to improve performance. Excessive dieting may indicate disordered eating (DE) behaviors and can result in clinical eating disorders. However, the current nutrition patterns that underly dieting culture are underexplored in endurance athletes. Therefore, the purpose of this study was to identify the sex differences in nutrition patterns among a group of endurance athletes.MethodsTwo-hundred and thirty-one endurance athletes (females = 124) completed a questionnaire regarding their dieting patterns and associated variables.ResultsThe majority of athletes did not follow a planned diet (70.1%). For endurance athletes on planned diets (n = 69), males were more likely follow a balanced diet (p = 0.048) and females were more likely to follow a plant-based diet (p = 0.021). Female endurance athletes not on a planned diet (n = 162) were more likely to have attempted at least one diet (p < 0.001). Male athletes attempted 2.0 ± 1.3 different diets on average compared to 3.0 ± 2.0 for females (p = 0.002). Female athletes were more likely to attempt ≥ three diets (p = 0.022). The most common diet attempts included carbohydrate/energy restrictive, plant-based, and elimination diets. Females were more likely to attempt ketogenic (p = 0.047), low-carbohydrate (p = 0.002), and energy restricted diets (p = 0.010). Females made up the entirety of those who attempted gluten-/dairy-free diets (F = 22.0%, M = 0.0%).ConclusionsBeing a female athlete is a major determinant of higher dieting frequency and continual implementation of popular restrictive dietary interventions. Sports dietitians and coaches should prospectively assess eating behavior and provide appropriate programming, education, and monitoring of female endurance athletes.

Effects of daily functional acorn cake consumption on insulin resistance in individuals with obesity or overweight and the metabolic syndrome: a placebo-controlled randomised clinical trial

AbstractThe metabolic syndrome is a multi-factorial condition and functional foods need more investigation as novel adjunct treatments for this group. This study aimed to determine the effects of daily consumption of a functional acorn cake in conjunction with energy restriction (119.50 kJ) on individuals with overweight or obesity and the metabolic syndrome. In this randomised double-blinded study, eighty-four participants were randomly allocated to either an energy-restricted diet plus two servings (2 × 30 g)/d of functional acorn cake (a cake made of acorn for the intervention group) (FC) (n 42) or an energy-restricted diet plus placebo cake (PC) (n 42). Body composition and biochemical parameters were measured before and after 10 weeks of intervention. Seventy-three participants completed this trial. No differences in loss of body weight, waist circumference, fat mass, fasting blood glucose and blood pressure were shown between two groups. Body weight decreased by 4·2 (sd 1·9) kg and 5·1 (sd 2·8) kg in PC and FC groups, respectively. Compared with PC, the consumption of FC resulted in a significant reduction in serum insulin (P = 0·02), homoeostasis model assessment for insulin resistance (P = 0·02), high-sensitivity C-reactive protein (P = 0·04) and a significant increase in adiponectin concentration (P = 0·04). Although lipid metabolism did not differ among groups, total cholesterol and HDL-cholesterol improved non-significantly in the FC group. Functional acorn cake as an adjunct to energy restriction could possibly improve insulin resistance in individuals with obesity. Further research is needed to elucidate whether functional acorn cake can be used as a preventive strategy for the metabolic syndrome in individuals with obesity.

Soy protein intake increased bone mineral density under nonenergy-deficiency conditions but decreased it under energy-deficiency conditions in young female rats

Many young individuals attempt to lose too much weight because of a false body image, which induces low bone mineral density (BMD) resulting from energy restriction. In addition, a decrease in estrogen has been observed along with the decrease in BMD. Estrogen is responsible for maintaining bone mass, and soybeans contain high levels of isoflavones, which have estrogen-like effects. Thus, we hypothesized that soy protein prevents low BMD caused by energy deficiency in young female rats. The purpose of this study was to examine the effect of soy protein intake on bone loss by energy deficiency in young female rats. Female Sprague-Dawley rats (6 weeks old) were randomly divided into the following 4 experimental groups: ad libitum feeding and casein diet (AL-Cas); ad libitum feeding and soy diet (AL-Soy); 40% energy restriction and casein diet (ER-Cas); and 40% energy restriction and soy diet (ER-Soy). The experimental period was 10.5 weeks. The AL-soy group had significantly higher BMD of the femur than the AL-Cas group (AL-Cas = 156 ± 5 mg/cm2, AL-Soy = 165 ± 7 mg/cm2; P < .05). Meanwhile, the ER-Soy group had significantly lower BMD of the tibia, femur, and lumbar spine than the ER-Cas group (ER-Cas = 147 ± 7 mg/cm2, ER-Soy = 133 ± 10 mg/cm2; P < .01). These results show that compared with ad libitum control groups, soy protein resulted in higher BMD under nonenergy deficiency, but under energy-deficiency conditions, it resulted in lower BMD.