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Obesity (Silver Spring, Md.) Jun 2020The objective of this study was to evaluate the effect of skipping breakfast on body composition and cardiometabolic risk factors. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
The objective of this study was to evaluate the effect of skipping breakfast on body composition and cardiometabolic risk factors.
METHODS
This study conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) evaluating breakfast skipping compared with breakfast consumption. Inclusion criteria included age ≥ 18, intervention duration ≥ 4 weeks, ≥ 7 participants per group, and ≥ 1 body composition measure. Random-effects meta-analyses of the effect of breakfast skipping on body composition and cardiometabolic risk factors were performed.
RESULTS
Seven RCTs (n = 425 participants) with an average duration of 8.6 weeks were included. Compared with breakfast consumption, breakfast skipping significantly reduced body weight (weighted mean difference [WMD] = -0.54 kg [95% CI: -1.05 to -0.03], P = 0.04, I = 21.4%). Percent body fat was reported in 5 studies and was not significantly different between breakfast skippers and consumers. Three studies reported on low-density lipoprotein cholesterol (LDL), which was increased in breakfast skippers as compared with breakfast consumers (WMD = 9.24 mg/dL [95% CI: 2.18 to 16.30], P = 0.01). Breakfast skipping did not lead to significant differences in blood pressure, total cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, C-reactive protein, insulin, fasting glucose, leptin, homeostatic model assessment of insulin resistance, or ghrelin.
CONCLUSIONS
Breakfast skipping may have a modest impact on weight loss and may increase LDL in the short term. Further studies are needed to provide additional insight into the effects of breakfast skipping.
Topics: Adolescent; Adult; Aged; Body Composition; Breakfast; Cardiovascular Diseases; Female; Humans; Middle Aged; Randomized Controlled Trials as Topic; Risk Factors; Young Adult
PubMed: 32304359
DOI: 10.1002/oby.22791 -
Nutrients Feb 2023There has been an emerging concern that non-nutritive sweeteners (NNS) can increase the risk of cardiometabolic disease. Much of the attention has focused on acute... (Meta-Analysis)
Meta-Analysis
There has been an emerging concern that non-nutritive sweeteners (NNS) can increase the risk of cardiometabolic disease. Much of the attention has focused on acute metabolic and endocrine responses to NNS. To examine whether these mechanisms are operational under real-world scenarios, we conducted a systematic review and network meta-analysis of acute trials comparing the effects of non-nutritive sweetened beverages (NNS beverages) with water and sugar-sweetened beverages (SSBs) in humans. MEDLINE, EMBASE, and The Cochrane Library were searched through to January 15, 2022. We included acute, single-exposure, randomized, and non-randomized, clinical trials in humans, regardless of health status. Three patterns of intake were examined: (1) uncoupling interventions, where NNS beverages were consumed alone without added energy or nutrients; (2) coupling interventions, where NNS beverages were consumed together with added energy and nutrients as carbohydrates; and (3) delayed coupling interventions, where NNS beverages were consumed as a preload prior to added energy and nutrients as carbohydrates. The primary outcome was a 2 h incremental area under the curve (iAUC) for blood glucose concentration. Secondary outcomes included 2 h iAUC for insulin, glucagon-like peptide 1 (GLP-1), gastric inhibitory polypeptide (GIP), peptide YY (PYY), ghrelin, leptin, and glucagon concentrations. Network meta-analysis and confidence in the network meta-analysis (CINeMA) were conducted in R-studio and CINeMA, respectively. Thirty-six trials involving 472 predominantly healthy participants were included. Trials examined a variety of single NNS (acesulfame potassium, aspartame, cyclamate, saccharin, stevia, and sucralose) and NNS blends (acesulfame potassium + aspartame, acesulfame potassium + sucralose, acesulfame potassium + aspartame + cyclamate, and acesulfame potassium + aspartame + sucralose), along with matched water/unsweetened controls and SSBs sweetened with various caloric sugars (glucose, sucrose, and fructose). In uncoupling interventions, NNS beverages (single or blends) had no effect on postprandial glucose, insulin, GLP-1, GIP, PYY, ghrelin, and glucagon responses similar to water controls (generally, low to moderate confidence), whereas SSBs sweetened with caloric sugars (glucose and sucrose) increased postprandial glucose, insulin, GLP-1, and GIP responses with no differences in postprandial ghrelin and glucagon responses (generally, low to moderate confidence). In coupling and delayed coupling interventions, NNS beverages had no postprandial glucose and endocrine effects similar to controls (generally, low to moderate confidence). The available evidence suggests that NNS beverages sweetened with single or blends of NNS have no acute metabolic and endocrine effects, similar to water. These findings provide support for NNS beverages as an alternative replacement strategy for SSBs in the acute postprandial setting.
Topics: Humans; Sugar-Sweetened Beverages; Aspartame; Ghrelin; Glucagon; Cyclamates; Network Meta-Analysis; Blood Glucose; Glucose; Non-Nutritive Sweeteners; Beverages; Sucrose; Insulin; Sugars; Glucagon-Like Peptide 1; Water
PubMed: 36839408
DOI: 10.3390/nu15041050 -
International Journal of Molecular... Mar 2023The study aimed to perform a systematic review and meta-analysis of the evidence for the prevention of future cancers following bariatric surgery. A systematic... (Meta-Analysis)
Meta-Analysis Review
The study aimed to perform a systematic review and meta-analysis of the evidence for the prevention of future cancers following bariatric surgery. A systematic literature search of the Cochrane Library, Embase, Scopus, Web of Science and PubMed databases (2007-2023), Google Scholar and grey literature was conducted. A meta-analysis was performed using the inverse variance method and random effects model. Thirty-two studies involving patients with obesity who received bariatric surgery and control patients who were managed with conventional treatment were included. The meta-analysis suggested bariatric surgery was associated with a reduced overall incidence of cancer (RR 0.62, 95% CI 0.46-0.84, < 0.002), obesity-related cancer (RR 0.59, 95% CI 0.39-0.90, = 0.01) and cancer-associated mortality (RR 0.51, 95% CI 0.42-0.62, < 0.00001). In specific cancers, bariatric surgery was associated with reduction in the future incidence of hepatocellular carcinoma (RR 0.35, 95% CI 0.22-0.55, < 0.00001), colorectal cancer (RR 0.63, CI 0.50-0.81, = 0.0002), pancreatic cancer (RR 0.52, 95% CI 0.29-0.93, = 0.03) and gallbladder cancer (RR 0.41, 95% CI 0.18-0.96, = 0.04), as well as female specific cancers, including breast cancer (RR 0.56, 95% CI 0.44-0.71, < 0.00001), endometrial cancer (RR 0.38, 95% CI 0.26-0.55, < 0.00001) and ovarian cancer (RR 0.45, 95% CI 0.31-0.64, < 0.0001). There was no significant reduction in the incidence of oesophageal, gastric, thyroid, kidney, prostate cancer or multiple myeloma after bariatric surgery as compared to patients with morbid obesity who did not have bariatric surgery. Obesity-associated carcinogenesis is closely related to metabolic syndrome; visceral adipose dysfunction; aromatase activity and detrimental cytokine, adipokine and exosomal miRNA release. Bariatric surgery results in long-term weight loss in morbidly obese patients and improves metabolic syndrome. Bariatric surgery may decrease future overall cancer incidence and mortality, including the incidence of seven obesity-related cancers.
Topics: Male; Humans; Female; Obesity, Morbid; Metabolic Syndrome; Bariatric Surgery; Risk; Incidence; Neoplasms
PubMed: 37047163
DOI: 10.3390/ijms24076192 -
Journal of the American Heart... Jun 2015Guidelines recommend exercise for cardiovascular health, although evidence from trials linking exercise to cardiovascular health through intermediate biomarkers remains... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Guidelines recommend exercise for cardiovascular health, although evidence from trials linking exercise to cardiovascular health through intermediate biomarkers remains inconsistent. We performed a meta-analysis of randomized controlled trials to quantify the impact of exercise on cardiorespiratory fitness and a variety of conventional and novel cardiometabolic biomarkers in adults without cardiovascular disease.
METHODS AND RESULTS
Two researchers selected 160 randomized controlled trials (7487 participants) based on literature searches of Medline, Embase, and Cochrane Central (January 1965 to March 2014). Data were extracted using a standardized protocol. A random-effects meta-analysis and systematic review was conducted to evaluate the effects of exercise interventions on cardiorespiratory fitness and circulating biomarkers. Exercise significantly raised absolute and relative cardiorespiratory fitness. Lipid profiles were improved in exercise groups, with lower levels of triglycerides and higher levels of high-density lipoprotein cholesterol and apolipoprotein A1. Lower levels of fasting insulin, homeostatic model assessment-insulin resistance, and glycosylated hemoglobin A1c were found in exercise groups. Compared with controls, exercise groups had higher levels of interleukin-18 and lower levels of leptin, fibrinogen, and angiotensin II. In addition, we found that the exercise effects were modified by age, sex, and health status such that people aged <50 years, men, and people with type 2 diabetes, hypertension, dyslipidemia, or metabolic syndrome appeared to benefit more.
CONCLUSIONS
This meta-analysis showed that exercise significantly improved cardiorespiratory fitness and some cardiometabolic biomarkers. The effects of exercise were modified by age, sex, and health status. Findings from this study have significant implications for future design of targeted lifestyle interventions.
Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Biomarkers; Cardiovascular Diseases; Exercise; Female; Health Status; Humans; Male; Middle Aged; Physical Fitness; Prognosis; Protective Factors; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Risk Reduction Behavior; Sex Factors; Young Adult
PubMed: 26116691
DOI: 10.1161/JAHA.115.002014 -
Neuroscience and Biobehavioral Reviews Sep 2017The brain-gut-axis is an interdependent system affecting neural functions and controlling our eating behaviour. In recent decades, neuroimaging techniques have... (Review)
Review
The brain-gut-axis is an interdependent system affecting neural functions and controlling our eating behaviour. In recent decades, neuroimaging techniques have facilitated its investigation. We systematically looked into functional and neurochemical brain imaging studies investigating how key molecules such as ghrelin, glucagon-like peptide-1 (GLP-1), peptide tyrosine-tyrosine (PYY), cholecystokinin (CCK), leptin, glucose and insulin influence the function of brain regions regulating appetite and satiety. Of the 349 studies published before July 2016 identified in the database search, 40 were included (27 on healthy and 13 on obese subjects). Our systematic review suggests that the plasma level of ghrelin, the gut hormone promoting appetite, is positively correlated with activation in the pre-frontal cortex (PFC), amygdala and insula and negatively correlated with activation in subcortical areas such as the hypothalamus. In contrast, the plasma levels of glucose, insulin, leptin, PYY, GLP-1 affect the same brain regions conversely. Our study integrates previous investigations of the gut-brain matrix during food-intake and homeostatic regulation and may be of use for future meta-analyses of brain-gut interactions.
Topics: Appetite; Brain; Gastrointestinal Tract; Hormones; Humans; Satiation
PubMed: 28669754
DOI: 10.1016/j.neubiorev.2017.06.013 -
Nutrients May 2021A disequilibrium of the gut microbial community has been closely associated with systemic inflammation and metabolic syndromes including type 2 diabetes. While low fibre... (Meta-Analysis)
Meta-Analysis
The Effect of Dietary Fibre on Gut Microbiota, Lipid Profile, and Inflammatory Markers in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomised Controlled Trials.
BACKGROUND
A disequilibrium of the gut microbial community has been closely associated with systemic inflammation and metabolic syndromes including type 2 diabetes. While low fibre and high fat diets may lead to dysbiosis of the gut microbiome as a result of the loss of useful microbes, it has been reported that a high fibre diet may prevent the fermentation of protein and may promote eubiosis of gut microbiota.
AIM
This review aims to evaluate the effect of dietary fibre (DF) on gut microbiota, lipid profile, and inflammatory markers in patients with type 2 diabetes.
METHODS
The PRISMA framework was relied on to conduct this systematic review and meta-analysis. Searches were carried out using electronic databases and reference list of articles.
RESULTS
Eleven studies were included in the systematic review, while ten studies were included in the meta-analysis. The findings revealed five distinct areas including the effects of DF on (a) gut microbiota (122 participants); (b) lipopolysaccharides (LPS, 79 participants) and lipopolysaccharides binding protein (LBP, 81 participants); (c) lipid profile; (d) inflammatory markers; and (e) body mass index (BMI, 319 participants). The relative abundance of increased by 0.73 (95% CI: 0.57, 0.89) in the DF group in contrast to the control ( < 0.05). With respect to LPS, the level was lower in the DF group than the control and the difference was significant ( < 0.05). The standardised mean difference for LPS was -0.45 (95% CI: -0.90, -0.01) although the difference between the two groups in relation to LBP was not significant ( = 0.08) and the mean difference was 0.92 (95% CI: -0.12, 1.95). While there was a decrease of -1.05 (95% CI: -2.07, -0.02) with respect to total cholesterol (356 participants) in the DF group as compared with the control ( < 0.05), both groups were not significantly different ( > 0.05) in the other lipid parameters. The difference between the groups was significant ( < 0.05) in relation to C-reactive protein, and the mean difference was 0.43 (95% CI: 0.02, 0.84). This could be due to the short duration of the included studies and differences in participants' diets including the amount of dietary fibre supplements. However, the groups were not significantly different ( > 0.05) with respect to the other inflammatory markers. The meta-analysis of the BMI showed that the DF group decreased by -0.57 (95% CI: -1.02, -0.12) as compared with the control and this was significant ( < 0.01).
CONCLUSION
DF significantly ( < 0.05) increased the relative abundance of and significantly decreased ( < 0.05) LPS, total cholesterol, and BMI as compared with the control. However, DF did not seem to have an effect that was significant on LBP, triglyceride, HDL cholesterol, LDL cholesterol, IL-6, TNF-α, adiponectin, and leptin. These findings have implications for public health in relation to the use of dietary fibre in nutritional interventions and as strategies for managing type 2 diabetes.
Topics: Acute-Phase Proteins; Bifidobacterium; Biomarkers; Body Mass Index; C-Reactive Protein; Carrier Proteins; Databases, Factual; Diabetes Mellitus, Type 2; Dietary Fiber; Dysbiosis; Gastrointestinal Microbiome; Humans; Lipids; Membrane Glycoproteins; Metabolic Syndrome; Randomized Controlled Trials as Topic; Triglycerides
PubMed: 34073366
DOI: 10.3390/nu13061805 -
Journal of Sport and Health Science Mar 2023This study investigates the effects of exercise training on exerkines in patients with type 2 diabetes mellitus to determine the optimal exercise prescription. (Meta-Analysis)
Meta-Analysis Review
Exercise training-induced changes in exerkine concentrations may be relevant to the metabolic control of type 2 diabetes mellitus patients: A systematic review and meta-analysis of randomized controlled trials.
BACKGROUND
This study investigates the effects of exercise training on exerkines in patients with type 2 diabetes mellitus to determine the optimal exercise prescription.
METHODS
A systematic search for relevant studies was performed in 3 databases. Randomized controlled trials investigating the effects of exercise training on at least one of the following exerkines were included: adiponectin, apelin, brain-derived neurotrophic factor, fetuin-A, fibroblast growth factor-21, follistatin, ghrelin, interleukin (IL)-6, IL-8, IL-10, IL-15, IL-18, leptin, myostatin, omentin, resistin, retinol-binding protein 4, tumor necrosis factor-α, and visfatin.
RESULTS
Forty randomized controlled trials were selected for data extraction (n = 2160). Exercise training induces changes in adiponectin, fetuin-A, fibroblast growth factor-21, IL-6, IL-10, leptin, resistin, and tumor necrosis factor-α levels but has no significant effects on apelin, IL-18, and ghrelin compared to controls. Physical exercise training favored large and positive changes in pooled exerkines (i.e., an overall effect size calculated from several exerkines) (Hedge's g = 1.02, 95% confidence interval (95%CI): 0.76-1.28), which in turn were related to changes in glycated hemoglobin (mean difference (MD) = -0.81%, 95%CI: -0.95% to -0.67%), fasting glucose (MD = -23.43 mg/dL, 95%CI: -30.07 mg/dL to -16.80 mg/dL), waist circumference (MD = -3.04 cm, 95%CI: -4.02 cm to -2.07 cm), and body mass (MD = -1.93 kg, 95%CI: -2.00 kg to -1.86 kg). Slightly stronger effects were observed with aerobic, resistance, or high-intensity interval protocols at moderate- to vigorous-intensity and with programs longer than 24 weeks that comprise at least 3 sessions per week and more than 60 min per session.
CONCLUSION
Exercise training represents an anti-inflammatory therapy and metabolism-improving strategy with minimal side effects for patients with type 2 diabetes mellitus.
Topics: Humans; Diabetes Mellitus, Type 2; Resistin; Apelin; Leptin; Ghrelin; Interleukin-10; Interleukin-18; Adiponectin; alpha-2-HS-Glycoprotein; Tumor Necrosis Factor-alpha; Randomized Controlled Trials as Topic; Exercise; Fibroblast Growth Factors
PubMed: 36351545
DOI: 10.1016/j.jshs.2022.11.003 -
Iranian Journal of Public Health Jan 2024Leptin has a great effect on bone through direct or indirect involvement in bone remodeling. Considering the ambiguities that exist regarding the effect of leptin on... (Review)
Review
BACKGROUND
Leptin has a great effect on bone through direct or indirect involvement in bone remodeling. Considering the ambiguities that exist regarding the effect of leptin on bone and bone-related diseases including osteoporosis, in this study, we aimed to conduct a systematic review of various studies on the effect of leptin on osteoporosis, which may find an answer to the existing ambiguities.
METHODS
The search was performed to review studies on the effects of leptin on osteoporosis by using several databases including Scopus, PubMed, Web of Science, and Google Scholar. Electronic searches were conducted on 5 Jan 2023. There was no limit on the publication date of the articles. The risk of bias for the animal study was assessed with the CAMARADES checklist, and the study quality assessment was also assessed based on the guidelines for in vivo experiments (ARRIVE). In this study, the risk of bias (quality) of human studies was assessed using the quality assessment checklists by NHLBI.
RESULTS
Overall, 34 articles were included for data extraction and quality assessment. Overall, 27 human studies and seven animal studies were included in the article. The results of most of the studies conducted in this study showed that leptin has a physiological role in maintaining bone mass and better bone quality and reduces bone marrow adipogenesis and increases bone mineral density (BMD). As plasma leptin levels increased, BMD values or bone formation biomarkers increased.
CONCLUSION
Leptin has an inhibitory role against bone resorption and increasing osteoprotegerin (OPG) levels, which, as a result, maintains bone density and reduces osteoclast activity, and has a positive relationship with increasing osteocalcin.
PubMed: 38694865
DOI: 10.18502/ijph.v53i1.14686 -
Journal of Clinical Medicine Oct 2019The effects of an intermittent fasting diet (IFD) in the general population are still controversial. In this study, we aimed to systematically evaluate the effectiveness...
The effects of an intermittent fasting diet (IFD) in the general population are still controversial. In this study, we aimed to systematically evaluate the effectiveness of an IFD to reduce body mass index and glucose metabolism in the general population without diabetes mellitus. Cochrane, PubMed, and Embase databases were searched to identify randomized controlled trials and controlled clinical trials that compared an IFD with a regular diet or a continuous calorie restriction diet. The effectiveness of an IFD was estimated by the weighted mean difference (WMD) for several variables associated with glucometabolic parameters including body mass index (BMI) and fasting glucose. The pooled mean differences of outcomes were calculated using a random effects model. From 2814 studies identified through a literature search, we finally selected 12 articles (545 participants). Compared with a control diet, an IFD was associated with a significant decline in BMI (WMD, -0.75 kg/m; 95% CI, -1.44 to -0.06), fasting glucose level (WMD, -4.16 mg/dL; 95% CI, -6.92 to -1.40), and homeostatic model assessment of insulin resistance (WMD, -0.54; 95% CI, -1.05 to -0.03). Fat mass (WMD, -0.98 kg; 95% CI, -2.32 to 0.36) tended to decrease in the IFD group with a significant increase in adiponectin (WMD, 1008.9 ng/mL; 95% CI, 140.5 to 1877.3) and a decrease in leptin (WMD, -0.51 ng/mL; 95% CI, -0.77 to -0.24) levels. An IFD may provide a significant metabolic benefit by improving glycemic control, insulin resistance, and adipokine concentration with a reduction of BMI in adults.
PubMed: 31601019
DOI: 10.3390/jcm8101645 -
BMC Oral Health Jun 2017This study aimed to assess the difference in serum levels of leptin and adiponectin in patients with periodontitis and in periodontally healthy individuals and evaluate... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
This study aimed to assess the difference in serum levels of leptin and adiponectin in patients with periodontitis and in periodontally healthy individuals and evaluate the changes in circulating leptin and adiponectin after periodontal therapy. Leptin and adiponectin are the most generally studied adipokines that function as inflammatory cytokines. Although the association between periodontitis and serum levels of leptin and adiponectin has been studied extensively, the results were not consistent.
METHODS
A systematic search of the Pubmed, Embase, Web of Science, and Cochrane Library up to September 2016 was conducted. The studies were screened and selected by two writers according to the specific eligibility criteria. The quality of included cross-sectional studies was assessed using the quality assessment form recommended by the Agency for Healthcare Research and Quality and Methodological Index for Nonrandomized Studies. The meta-analyses were conducted using the STATA 12.0 software.
RESULTS
A total of 399 manuscripts were yielded and 25 studies were included in the present meta-analysis. Significantly elevated serum levels of leptin and decreased serum levels of adiponectin in patients with periodontitis were observed in the subgroup analysis of body mass index (BMI) <30. The overall and subgroup analyses showed no significant change in the serum levels of leptin in patients with periodontitis after periodontal treatment. The subgroup analysis of systemically healthy patients showed no significant change in serum levels of adiponectin in patients with periodontitis after periodontal treatment.
CONCLUSIONS
The present meta-analysis supported elevated serum levels of leptin and decreased serum levels of adiponectin in patients with periodontitis compared with controls in the BMI <30 population. In systemically healthy patients with periodontitis, serum levels of leptin and adiponectin do not significantly change after periodontal treatment.
Topics: Adiponectin; Humans; Leptin; Periodontitis
PubMed: 28662701
DOI: 10.1186/s12903-017-0395-0