-
1.
Interventions for the prevention of weight gain during festive and holiday periods in children and adults: A systematic review.
Guerrero-Magaña, DE, Urquijo-Ruiz, LG, Ruelas-Yanes, AL, Martínez-Contreras, TJ, Díaz-Zavala, RG, Candia-Plata, MDC, Esparza-Romero, J, Haby, MM
Obesity reviews : an official journal of the International Association for the Study of Obesity. 2025;26(1):e13836
-
-
-
Free full text
-
Plain language summary
Festive and holiday periods are often associated with weight gain due to changes in eating and activity patterns. For example, it has been suggested that there may be an accelerated gain in weight in children and adolescents during the summer school holidays and that this may especially affect high-risk groups, such as certain racial populations (black, Hispanic) and those with overweight or obesity. The aim of this study was to assess the impact of interventions designed to prevent weight gain during festive and holiday periods in children and adults. This study was a systematic review of twelve studies - randomised controlled trials (RCTs), cluster-RCTs, and non-RCTs. Results showed that the evidence for interventions targeting prevention of BMI increases in children during summer showed positive results, while interventions to prevent weight gain in adults during December holiday periods also showed consistent positive effects. Authors concluded by highlighting potential interventions that may help prevent weight gain during holiday periods. However, the evidence quality is generally low, and further research is needed to improve the robustness of these findings and extend them to more diverse populations.
Abstract
Some periods during the year, such as festive and summer holiday periods, have been associated with weight gain. We aimed to assess the effect of interventions for the prevention of body weight gain during festive and holiday periods in children and adults. A systematic search was conducted in six databases and supplementary sources until January 4, 2023. We included randomized controlled trials (RCTs), cluster-RCTs, and non-RCTs. Our primary outcome measure was the change in body weight in adults or the change in BMI z-score or BMI percentile in children and adolescents. From 4216 records, 12 primary studies (from 22 reports) met the inclusion criteria-10 from the United States, one from the United Kingdom, and one from Chile. Two studies had a low risk of bias, two moderate, seven high, and one critical risk of bias. The meta-analysis in children included four of seven studies during the summer holidays (six interventions) and showed a mean difference in BMI z-score favoring the intervention group (-0.06 [95% CI -0.10, -0.01], p = 0.01, I2 = 0%, very low certainty evidence). The meta-analysis in adults included five studies during festive periods with a mean difference in weight favoring the intervention group (-0.99 kg [95% CI -2.15, 0.18], p = 0.10, I2 = 89%, very low certainty evidence). This review has highlighted potential interventions to prevent the increase in body weight during holiday periods. More work is needed to improve the quality of the evidence and to extend it to countries outside of the United States and United Kingdom and to the adolescent population.
-
2.
Physical activity and risk of depression in adolescents: A systematic review and meta-analysis of prospective observational studies.
Hou, J, Deng, Q, Sha, L, Zhu, J, Xiang, R, Zhao, X, Xiao, C, Qin, C, Qu, Y, Han, T, et al
Journal of affective disorders. 2025;371:279-288
-
-
-
Free full text
-
Plain language summary
Depression is often considered as an adult mental health condition, yet children in particular adolescents, commonly suffer from it. Physical activity (PA) has been demonstrated to pose a positive impact on mental health. This beneficial effect could involve both physiological and psychosocial mechanisms. This study aimed to evaluate the overall association between PA and depression in adolescents. This research was a systematic review and meta-analysis of eleven prospective observational studies with a total of 59,786 adolescents. Results showed that higher levels of PA were associated with a reduced risk of depression in the target population. Authors concluded that their findings highlight the importance of policies targeting increased levels of PA in adolescents.
Abstract
BACKGROUND While the benefits of physical activity (PA) on depression in adults have been well-established, its impact on depression in adolescents remains understudied. This study aimed to examine the relationship between PA and depression in adolescents, aggregating published prospective observational studies. METHODS We searched MEDLINE, Embase, Cochrane, and PsycINFO, for prospective observational studies that examined the relationship between PA and depression in adolescents from the inception of these databases to November 17, 2022, without any language restrictions. Two independent reviewers performed data extraction and assessed the risk of bias. We utilized a random-effects model to calculate the pooled odds ratios (ORs) and 95 % confidence intervals (95%CIs). Subgroup analyses were conducted to explore potential sources of heterogeneity. RESULTS This study included 11 original articles, involving 59,786 adolescents (46.4 % male). Primary analysis revealed that adolescents who engaged in higher levels of PA showed a 3 % significantly decreased risk of developing depression compared to those with lower levels (OR = 0.97, 95%CI = 0.94-0.99, P = 0.01; I2 = 41.7 %). Sensitivity analyses confirmed the robustness of these findings. Subgroup analyses demonstrated heterogeneity to be primarily attributed to data source, geographic region, and follow-up period (Pinteraction< 0.01, 0.01 and 0.01, respectively), while no significant sex-specific association was found (Pinteraction = 0.30). CONCLUSIONS Our systematic review and meta-analysis of prospective observational studies indicates that higher levels of PA are associated with a reduced risk of depression in adolescents. This highlights the need for policies to promote increased PA levels among adolescents for the prevention of depression.
-
3.
The impact of behavioral weight management interventions on eating behavior traits in children with overweight or obesity: Systematic review and meta-analysis.
Colombo, PE, Wickramarachchi, M, Lakshmi, A, Kudlek, L, Ahern, A, Tait, S, Reid, N, Jones, RA, Smith, AD
Obesity reviews : an official journal of the International Association for the Study of Obesity. 2025;26(1):e13839
-
-
-
Free full text
-
Plain language summary
Childhood obesity is challenging to reverse, tracks into adolescence and adulthood, and the negative health effects follow into adulthood also. The high prevalence of childhood obesity and negative associated consequences highlights the need for effective weight management treatments. Behavioural weight management interventions (BWMIs) addressing diet, physical activity, and lifestyle habits are key treatments for childhood and adolescent obesity. This study aimed to assess the impact of child BWMIs on eating behaviour traits (EBTs) compared to the usual care, inactive, or minimal intervention group. This research was a systematic review with narrative synthesis and meta-analysis of randomised controlled trials of eight articles with a total of 11,384 participants (children living with overweight or obesity). Results showed that paediatric BWMIs resulted in positive short-term effects on dietary restraint at programme completion. Additionally, the interventions resulted in positive improvements in children's emotional eating, external eating, food responsiveness, and enjoyment of food. However, these improvements were predominantly observed at the end of the intervention, with effects no longer significant at later follow-up. Authors concluded that BWMIs are beneficial for the improvement of some EBTs at intervention end, including dietary restraint, emotional eating, external eating, food responsiveness, and enjoyment of food.
Abstract
INTRODUCTION Behavioral weight management interventions (BWMIs) are an evidence-based strategy for addressing childhood obesity. Targeting eating behavior traits (EBTs; individual tendencies determining food intake/occasions) could play a pivotal role in improving the effectiveness of these behavioral interventions. The present study describes a systematic review and meta-analysis of the impact of BWMIs on eating behavior traits in children with overweight or obesity. METHODS Seven databases were searched, and eligible studies included randomized controlled trials reporting EBT outcomes following BWMIs delivered to children with overweight or obesity (<18 years of age). Random effects meta-analyses were conducted to compare EBT outcomes for intervention and control groups. Synthesis without meta-analysis (SWiM) was applied for EBTs where meta-analysis was not feasible. RESULTS The review identified eight trials characterizing the impact of BWMIs on 15 EBTs. Meta-analyses of data from three trials at intervention completion and post-intervention (average of 28 weeks [±8]) revealed positive short-term increases in dietary restraint (SMD random effect 0.42 [95% CI 0.13, 0.70]). However, these effects were not sustained at follow-up. Improvements in emotional eating, external eating, food responsiveness, and enjoyment of food were shown in studies which could not be pooled quantitatively. CONCLUSION BWMIs in children living with overweight/obesity are beneficial for the improvement of some EBTs at intervention completion including dietary restraint, emotional eating, external eating, food responsiveness, and enjoyment of food. However, this remains a relatively unexplored area and more research is needed to strengthen understanding of the multifaceted impact of child BWMIs on a comprehensive range of EBTs.
-
4.
Efficacy of probiotics or synbiotics in critically ill patients: A systematic review and meta-analysis.
Lou, J, Cui, S, Huang, N, Jin, G, Chen, C, Fan, Y, Zhang, C, Li, J
Clinical nutrition ESPEN. 2024;59:48-62
-
-
-
Free full text
-
Plain language summary
The intestinal microbiota is a complex microbial community that plays an irreplaceable role in human life. Intestinal dysbiosis is very common in patients with critical illnesses. The aim of this study was to assess the efficacy and safety of probiotics or synbiotics in preventing ventilator associated pneumonia (VAP) in critically ill patients in the intensive care unit (ICU). This study was a systematic review and meta-analysis of thirty-three trials (n=4 retrospective studies and n=29 randomised controlled studies). A total of 7886 patients were grouped into the probiotics or synbiotics group (n= 4065) and control group (n= 3821). Results showed that probiotics or synbiotics significantly reduced the incidence of VAP and sepsis, as well as the duration of mechanical support, length of hospital stay, length of ICU stay, and ICU morality. Authors concluded that probiotics or synbiotics supplementation plays a beneficial role in critically ill patients and presents a novel approach to the management of critical diseases.
Abstract
BACKGROUND This latest systematic review and meta-analysis aim to examine the effects of probiotic and synbiotic supplementation in critically ill patients. METHODS Relevant articles were retrieved from PubMed, Embase, the Cochrane Database, and the Web of Science. The primary output measure was the incident of ventilator-associated pneumonia, and the secondary outputs were diarrhea, Clostridium diffusion infection (CDI), incident of sepsis, incident of hospital acquired pneumonia, duration of mechanical exploitation, ICU mortality rate, length of ICU stay, in hospital mortality, and length of hospital stay. Data were pooled and expressed as Relative Risk(RR) and Standardized Mean Difference (SMD) with a 95 % confidence interval (CI). RESULTS 33 studies were included in this systematic review and meta-analysis, with 4065 patients who received probiotics or synbiotics (treatment group) and 3821 patients who received standard care or placebo (control group). The pooled data from all included studies demonstrated that the treatment group has significantly reduced incidence of ventilation-associated pneumonia (VAP) (RR = 0.80; 95 % CI: 0.67-0.96; p = 0.021, I2 = 52.5 %) and sepsis (RR = 0.97; 95 % CI: 0.66-1.42; p = 0.032, I2 = 54.4 %), As well as significantly increased duration of mechanical exploitation (SMD = -0.47; 95 % CI: -0.74-0.20, p = 0.012, I2 = 63.4 %), ICU mobility (RR = 0.95; 95 % CI: 0.71-1.27; p = 0.004, I2 = 62.8 %), length of ICU stay (SMD = -0.29; 95 % CI: -0.58-0.01; p = 0.000, I2 = 82.3 %) and length of hospital stay (SMD = -0.33; 95 % CI: -0.57-0.08, p = 0.000, I2 = 74.2 %) than the control group. There were no significant differences in diarrhea, CDI, incidence of hospital acquired pneumonia, and in hospital mortality between the two groups. CONCLUSION Our meta-analysis showed that probiotic and synbiotic supplements are beneficial for critically ill patients as they significantly reduce the incidence of ventilator associated pneumonia and sepsis, as well as the duration of mechanical exploitation, length of hospital stay, length of ICU stay, and ICU mortality. However, this intervention has minimal impact on diarrhea, CDI, incidence of hospital acquired pneumonia, and in hospital mortality in critically ill patients.
-
5.
Effect of probiotics or prebiotics on thyroid function: A meta-analysis of eight randomized controlled trials.
Shu, Q, Kang, C, Li, J, Hou, Z, Xiong, M, Wang, X, Peng, H
PloS one. 2024;19(1):e0296733
-
-
-
-
Free full text
Plain language summary
The gut microbiome is thought to play a role in thyroid disorders, mediated by regulating iodine uptake, degradation and enterohepatic cycling of thyroid hormones, and differences in microbiome composition between patients with thyroid disorders and healthy individuals have been observed. The aim of this systematic review and meta-analysis was to evaluate the effect of pro-, pre- and synbiotics on thyroid function (thyroid stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) and thyroid stimulating hormone receptor antibody (TRAb)) in patients with and without thyroid disorders. 8 randomised controlled trials including 367 participants were included in the review and meta-analysis. Neither pro-, pre- nor synbiotics had a significant effect on TSH, fT4 or fT3 but pre- and probiotics lead to a significant reduction in TRAb in patients with Graves’ disease.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Current evidence does not support a measurable effect of probiotic, prebiotic or symbiotic supplementation on thyroid hormone levels.
- There may be some benefits of these supplements for patients with Grave’s disease, in terms of lowering their thyroid stimulating hormone antibody levels.
Evidence Category:
-
X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Introduction
Research has highlighted the important role that the gut microbiome might play in thyroid function. As such, the potential role for probiotics and prebiotics to manipulate thyroid function has been considered. Given the inconsistencies in study findings, this systematic review aimed to assess the current consensus in the research.
Methods
- This systematic review was completed in accordance with the PRISMA guidelines.
- The search was performed using the following databases: MEDLINE, Scopus, Web of Science and Embase, plus a manual search and search of grey literature.
- After exclusions, eight peer-reviewed randomised controlled trials were included in the systematic review and meta analysis.
- Studies were conducted in China, Iran and Italy and included a range of different probiotic, prebiotic and synbiotic supplements at varying doses.
- The study included a heterogeneous sample of 367 participants, comprising individuals at risk of thyroid disorders, those diagnosed with thyroid disorders, individuals with obesity, and postmenopausal women.
- A number of outcome measures were considered including: free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), and thyroid stimulating hormone receptor antibody (TRAb) levels.
- Three studies were found to have low risk of bias, with four studies raising concerns of bias and one being deemed to have a high risk of bias.
Results
- The meta-analysis showed no significant differences (following supplementation) in a number of key hormones: thyroid stimulating hormone (TSH) (SMD: -0.01, 95% CI: −0.21, 0.20); free thyroxine (fT4) (SMD: 0.04, 95% CI: −0.29, 0.21); free triiodothyronine (FT3) (SMD: 0.45, 95% CI: −0.14, 1.03).
- Analysis revealed supplementation was associated with a significant reduction in thyroid stimulating hormone receptor antibody (TRAb) levels (SMD: -0.85, 95% CI: -1.54, -0.15).
Conclusion
- The meta-analysis would suggest that supplementing with probiotics, prebiotics and synbiotics has little impact on the level of thyroid hormones.
- Supplementing with probiotics, prebiotics and synbiotics may, however, have an impact on thyroid stimulating hormone receptor antibody levels, by reducing them.
Clinical practice applications:
- Current research evidence does not support the role of probiotics, prebiotics or synbiotics in influencing thyroid hormone levels.
- The use of probiotics, prebiotics and synbiotics may be a helpful additional strategy in managing patients with Grave’s disease, where thyroid stimulating hormone receptor antibody levels are raised.
Considerations for future research:
- Future research would benefit from focusing on individual sample groups with specific thyroid diagnoses.
- Additional studies would benefit from comparing the effects of probiotics, prebiotics and synbiotics in patients with Grave’s Disease.
- Since hormone levels do not always correlate well with subjective experience of thyroid symptoms, future studies might like to consider patient-report measures of health and wellbeing.
Abstract
BACKGROUND Microbiome-directed therapies are increasingly utilized to optimize thyroid function in both healthy individuals and those with thyroid disorders. However, recent doubts have been raised regarding the efficacy of probiotics, prebiotics, and synbiotics in improving thyroid function. This systematic review aimed to investigate the potential relationship between probiotics/prebiotics and thyroid function by analyzing the impact on thyroid hormone levels. METHODS We conducted a comprehensive systematic review and meta-analysis of randomized controlled trials that investigated the effects of probiotics, prebiotics, and synbiotics on free triiodothyronine (fT3), free thyroxine (fT4), thyroid stimulating hormone (TSH), and thyroid stimulating hormone receptor antibody (TRAb) levels. We searched for articles from PubMed, Scopus, Web of Science, and Embase up until April 1st, 2023, without any language restriction. Quantitative data analysis was performed using a random-effects model, with standardized mean difference (SMD) and 95% confidence interval as summary statistics. The methods and results were reported according to the PRISMA2020 statement. RESULTS A total of eight articles were included in this review. The meta-analysis showed no significant alterations in TSH (SMD: -0.01, 95% CI: -0.21, 0.20, P = 0.93; I2: 0.00%), fT4 (SMD: 0.04, 95% CI: -0.29, 0.21, P = 0.73; I2: 0.00%) or fT3 (SMD: 0.45, 95% CI: -0.14, 1.03, P = 0.43; I2: 78.00%), while a significant reduction in TRAb levels was observed (SMD: -0.85, 95% CI: -1.54, -0.15, P = 0.02; I2: 18.00%) following probiotics/prebiotics supplementation. No indication of publication bias was found. CONCLUSIONS Probiotics/prebiotics supplementation does not influence thyroid hormone levels, but may modestly reduce TRAb levels in patients with Graves' disease.
-
6.
The synergistic effect of herbal medicine and probiotics in pediatric functional constipation: A systematic review and meta-analysis.
Kim, E, Chang, S, Nam, J, Park, N, Min, SY
Medicine. 2024;103(7):e36899
-
-
-
Free full text
-
Plain language summary
Paediatric functional constipation (PFC) is a prevalent gastrointestinal disorder in children. The initial approach to managing PFC involves demystification, education, toilet training, and the use of laxatives. Using laxatives can lead to various adverse effects therefore, patients with functional constipation typically adopt a self-management approach and explore complementary and alternative therapies. The aim of this study was to analyse the synergistic effect of herbal medicine (HM) combined with probiotics in the treatment of PFC, by comparing it to the use of probiotics alone. This study was a systematic review and meta-analysis of twenty-two randomised controlled trials. Results showed that the combination of HM with probiotics may yield significantly greater benefits for total effective rate when compared to probiotics alone. Furthermore, HM combined with probiotics could potentially reduce the recurrence rate by 70% compared to probiotics alone. Authors concluded that HM could potentially offer advantages in enhancing the efficacy rate and Bristol faecal score, influencing gastrointestinal peptide hormones, decreasing inflammation indicators and lowering the recurrence rate among children with functional constipation.
Abstract
BACKGROUND Pediatric functional constipation (PFC) is a prevalent and persistent gastrointestinal disorder, that requires various treatments, including alternative approaches. This review assessed the synergistic efficacy of herbal medicine (HM) and probiotics for PFC. METHODS We conducted a comprehensive search of 11 databases, including English, Chinese, and Korean databases, until June 29, 2023. The inclusion criteria were randomized clinical trials (RCTs) comparing the intervention of HM with probiotics to that of the same probiotics. Statistical analyses included calculation of the mean difference (MD), standardized MD, risk ratio (RR) with a 95% confidence interval (CI), and assessment of risk of bias using Review Manager Version 5.4 software. The Grading of Recommendations Assessment, Development, and Evaluation rating system was used to evaluate evidence quality. Potential publication bias was assessed using funnel plots, Egger test, the fail-safe N test, and Duval and Tweedie trim and fill method. RESULTS A total of 22 RCTs involving 2228 patients were included in the meta-analysis. The HM and probiotics group exhibited superior outcomes compared to the probiotics alone group in various parameters: total effective rate (RR: 1.24, 95% CI: 1.19-1.29, P < .001), Bristol fecal Score (MD: 0.80, 95% CI: 0.71-0.89, P < .001), gastrointestinal peptide hormone (motilin) (MD: 35.37, 95% CI: 24.64-64.10, P < .001), inflammation indicator (nitrous oxide) (MD: -12.45, 95% CI: -15.12 to -9.77, P < .001), minimal sensitive volume of the rectum (MD: -8.7, 95% CI: -10.91 to -6.49, P < .001), and recurrence rate (RR: 0.30, 95% CI: 0.21-0.43, P < .001). CONCLUSION The combination of HM and probiotics may exhibit a synergistic effect on PFC. Nevertheless, it is imperative to undertake rigorously planned RCTs to comprehensively evaluate the synergistic efficacy of HM and probiotics.
-
7.
Effects of Intermittent Energy Restriction Compared with Those of Continuous Energy Restriction on Body Composition and Cardiometabolic Risk Markers - A Systematic Review and Meta-Analysis of Randomized Controlled Trials in Adults.
Schroor, MM, Joris, PJ, Plat, J, Mensink, RP
Advances in nutrition (Bethesda, Md.). 2024;15(1):100130
-
-
-
Free full text
-
Plain language summary
Intermittent energy restriction (IER) diets, such as the 5:2 diet, time-restricted eating (TRE), and alternate-day fasting (ADF), are gaining popularity. According to previous research, IER protocols effectively manage obesity and may have many other health benefits, including improving metabolic health. This systematic review and meta-analysis of twenty-eight parallel-design randomised controlled trials looked at the benefits of IER protocols, such as ADF, TRE, and the 5:2 diet, and the effects of continuous energy restriction (CER) on anthropometric and cardiometabolic outcomes. The results of this systematic review and meta-analysis showed that both the IER and CER are equally beneficial. However, IER protocols showed greater but clinically insignificant improvements in fat-free mass and waist circumference in healthy adults. IER and CER protocols were not different in improving the lipid profile, glucose and insulin levels and blood pressure. Different IER diets showed different positive effects on metabolic parameters. Future robust studies are required to assess the effects of these energy-restriction diets on metabolic and anthropometric parameters because of the high variability in the included studies. However, healthcare professionals can use the results of this review to understand the potential clinical utility of various energy-restriction diets.
Abstract
The interest in intermittent energy restriction (IER) diets as a weight-loss approach is increasing. Different IER protocols exist, including time-restricted eating (TRE), alternate-day fasting (ADF), and the 5:2 diet. This meta-analysis compared the effects of these IER diets with continuous energy restriction (CER) on anthropometrics and cardiometabolic risk markers in healthy adults. Twenty-eight trials were identified that studied TRE (k = 7), ADF (k = 10), or the 5:2 diet (k = 11) for 2-52 wk. Energy intakes between intervention groups within a study were comparable (17 trials), lower in IER (5 trials), or not reported (6 trials). Weighted mean differences (WMDs) were calculated using fixed- or random-effects models. Changes in body weight [WMD: -0.42 kg; 95% confidence interval (CI): -0.96 to 0.13; P = 0.132] and fat mass (FM) (WMD: -0.31 kg; 95% CI: -0.98 to 0.36; P = 0.362) were comparable when results of the 3 IER diets were combined and compared with those of CER. All IER diets combined reduced fat-free mass (WMD: -0.20 kg; 95% CI: -0.39 to -0.01; P = 0.044) and waist circumference (WMD: -0.91 cm; 95% CI: -1.76 to -0.06; P = 0.036) more than CER. Effects on body mass index [BMI (kg/m2)], glucose, insulin, homeostatic model assessment for insulin resistance (HOMA-IR), serum lipid and lipoprotein concentrations, and blood pressure did not differ. Further, TRE reduced body weight, FM, and fat-free mass more than CER, whereas ADF improved HOMA-IR more. BMI was reduced less in the 5:2 diet compared with CER. In conclusion, the 3 IER diets combined did not lead to superior improvements in anthropometrics and cardiometabolic risk markers compared with CER diets. Slightly greater reductions were, however, observed in fat-free mass and waist circumference. To what extent differences in energy intakes between groups within studies may have influenced these outcomes should be addressed in future studies.
-
8.
Effect of Calorie Restriction and Intermittent Fasting Regimens on Brain-Derived Neurotrophic Factor Levels and Cognitive Function in Humans: A Systematic Review.
Alkurd, R, Mahrous, L, Zeb, F, Khan, MA, Alhaj, H, Khraiwesh, HM, Faris, ME
Medicina (Kaunas, Lithuania). 2024;60(1)
-
-
-
Free full text
Plain language summary
Brain-derived neurotrophic factor (BDNF) is a protein that plays a crucial role in brain development, cognition and metabolism. Intermittent fasting (IF) is a promising therapeutic strategy for managing metabolic disorders and improving cognitive function. Therefore, this systematic review of sixteen experimental and observational studies investigated the effect of IF on BDNF production and improvements in cognition through the BDNF pathway in healthy adults and people with metabolic disorders. Included studies focused on different IF regimens such as calorie restriction (CR), alternate-day fasting (ADF), time-restricted eating (TRE) and Ramadan model of intermittent fasting (RIF) Future, well-controlled, long-term, robust studies are required to assess the effect of different IF regimens on the production of BDNF and cognitive function in people with metabolic disorders, as the current research is inconclusive. However, healthcare professionals can use the review to understand the potential beneficial effects of IF on cognition and metabolic health in humans.
Abstract
Background: The potential positive interaction between intermittent fasting (IF) and brain-derived neurotrophic factor (BDNF) on cognitive function has been widely discussed. This systematic review tried to assess the efficacy of interventions with different IF regimens on BDNF levels and their association with cognitive functions in humans. Interventions with different forms of IF such as caloric restriction (CR), alternate-day fasting (ADF), time-restricted eating (TRE), and the Ramadan model of intermittent fasting (RIF) were targeted. Methods: A systematic review was conducted for experimental and observational studies on healthy people and patients with diseases published in EMBASE, Scopus, PubMed, and Google Scholar databases from January 2000 to December 2023. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statements (PRISMA) for writing this review. Results: Sixteen research works conducted on healthy people and patients with metabolic disorders met the inclusion criteria for this systematic review. Five studies showed a significant increase in BDNF after the intervention, while five studies reported a significant decrease in BDNF levels, and the other six studies showed no significant changes in BDNF levels due to IF regimens. Moreover, five studies examined the RIF protocol, of which, three studies showed a significant reduction, while two showed a significant increase in BDNF levels, along with an improvement in cognitive function after RIF. Conclusions: The current findings suggest that IF has varying effects on BDNF levels and cognitive functions in healthy, overweight/obese individuals and patients with metabolic conditions. However, few human studies have shown that IF increases BDNF levels, with controversial results. In humans, IF has yet to be fully investigated in terms of its long-term effect on BDNF and cognitive functions. Large-scale, well-controlled studies with high-quality data are warranted to elucidate the impact of the IF regimens on BDNF levels and cognitive functions.
-
9.
Reducing meat and/or dairy consumption in adults: a systematic review and meta-analysis of effects on protein intake, anthropometric values, and body composition.
Habumugisha, T, Engebretsen, IMS, Måren, IE, Kaiser, CWM, Dierkes, J
Nutrition reviews. 2024;82(3):277-301
-
-
-
Free full text
-
Plain language summary
Reduced consumption of meat and dairy is being encouraged over climate change fears, and health implications. However, meat and dairy provide high quality protein and nutrients and concerns have grown over nutrient deficiencies in people on plant-based diets. This systematic review and meta-analysis of 19 randomised control trials (RCTs) aimed to determine the effect of a reduced meat/dairy diet in protein intake, and body shape and composition. The results showed that the RCTs included ran for a median duration of 12 weeks. Participants on a reduced meat/dairy diet had lower protein intakes, and reduced meat/dairy diet had no effect on body weight, body mass index, waist circumference, body fat, or muscle mass. It was concluded that a low meat/dairy diet decreases protein intake, however it does not affect body shape, or composition. It was also concluded that studies of longer duration are warranted to determine long-term effects. This study could be used by healthcare professionals to understand that reduced meat/dairy intake over a moderate period of time may have no effect on body shape or composition but will result in lower protein intakes.
Abstract
CONTEXT Consumers are increasingly encouraged to reduce meat and dairy consumption. However, few meta-analyses of randomized controlled trials (RCTs) on the effect of reducing meat and/or dairy on (absolute) protein intake, anthropometric values, and body composition are available. OBJECTIVE The aim of this systematic review and meta-analysis was to evaluate the effect of reducing meat and/or dairy consumption on (absolute) protein intake, anthropometric values, and body composition in adults aged ≥ 45 years. DATA SOURCES The MEDLINE, Cochrane CENTRAL, Embase, ClinicalTrials.gov, and International Clinical Trials Registry Platform databases were searched up to November 24, 2021. DATA EXTRACTION Randomized controlled trials reporting protein intake, anthropometric values, and body composition were included. DATA ANALYSIS Data were pooled using random-effects models and expressed as the mean difference (MD) with 95%CI. Heterogeneity was assessed and quantified using Cochran's Q and I2 statistics. In total, 19 RCTs with a median duration of 12 weeks (range, 4-24 weeks) and a total enrollment of 1475 participants were included. Participants who consumed meat- and/or dairy-reduced diets had a significantly lower protein intake than those who consumed control diets (9 RCTs; MD, -14 g/d; 95%CI, -20 to -8; I2 = 81%). Reducing meat and/or dairy consumption had no significant effect on body weight (14 RCTs; MD, -1.2 kg; 95%CI, -3 to 0.7; I2 = 12%), body mass index (13 RCTs; MD, -0.3 kg/m2; 95%CI, -1 to 0.4; I2 = 34%), waist circumference (9 RCTs; MD, -0.5 cm; 95%CI, -2.1 to 1.1; I2 = 26%), amount of body fat (8 RCTs; MD, -1.0 kg; 95%CI, -3.0 to 1.0; I2 = 48%), or lean body mass (9 RCTs; MD, -0.4 kg; 95%CI, -1.5 to 0.7; I2 = 0%). CONCLUSION Reduction of meat and/or dairy appears to reduce protein intake. There is no evidence of a significant impact on anthropometric values or body composition. More long-term intervention studies with defined amounts of meat and dairy are needed to investigate the long-term effects on nutrient intakes and health outcomes. SYSTEMATIC REVIEW REGISTRATION PROSPERO registration no. CRD42020207325.
-
10.
Systematic review and meta-analysis of nutrient supplements for treating sarcopenia in people with chronic obstructive pulmonary disease.
Huang, WJ, Ko, CY
Aging clinical and experimental research. 2024;36(1):69
-
-
-
Free full text
-
Plain language summary
Tobacco smoking and air pollution are leading causes of chronic obstructive pulmonary disease (COPD). Mortality and morbidity are on the rise worldwide due to the increase in COPD. COPD is a risk factor for sarcopenia, an age-related reduction in muscle mass and muscle strength. Non-pharmaceutical interventions, such as nutritional supplementation, are considered a management strategy for sarcopenia related to COPD, as they can address nutritional deficiencies and energy requirements in old age. This systematic review and meta-analysis included twenty-nine randomised controlled trials to assess the effects of nutritional supplementation for reducing sarcopenia in patients with COPD. The included studies used different nutritional supplements such as energy-type nutritional supplements, essential amino acids, essential amino acid-enriched nutritional supplements, whey protein, β-hydroxy β-methyl butyrate, creatine, creatine in combination with coenzyme Q10, vitamin D, vitamin B12, polyunsaturated fatty acids, magnesium citrate or nutritional antioxidant supplements. The intervention duration ranged from four weeks to twenty-four weeks. The result of this systematic review and meta-analysis showed a significant improvement in body weight, fat-free mass, and a 6-minute walk test. There was a non-significant improvement in handgrip strength and quadriceps muscle strength. Healthcare professionals can use the results of this study to understand the benefits of nutritional supplementation in improving body composition and muscle strength. However, further robust studies are required to evaluate the efficacy of nutritional supplementation in COPD patients due to the high heterogeneity of the included studies.
Abstract
Individuals with chronic obstructive pulmonary disease (COPD) are prone to malnutrition and sarcopenia as a result of nutritional deficiencies and increased energy metabolism. However, the effects of nutrient supplements (NS) on treating sarcopenia in patients with COPD are not well established from systematic evidence. This meta-analysis examined the effect of NS on sarcopenia in patients with COPD. A systematic search of multiple databases was conducted, and 29 randomized controlled trials involving 1625 participants (age, mean [SD] = 67.9 [7.8] years) were analyzed. NS demonstrated significant improvements in body weight (MD,1.33 kg; 95% CI, 0.60, 2.05 kg; P = 0.0003; I2 = 87%), fat-free mass index (MD, 0.74 kg/m2; 95% CI, 0.21, 1.27 kg/m2; P = 0.007; I2 = 75%), and 6-min walk test (MD, 19.43 m; 95% CI, 4.91, 33.94 m; P = 0.009; I2 = 81%) compared with control. However, NS had nonsignificant effects on handgrip strength (SMD, 0.36; 95% CI, - 0.15, 0.88; P = 0.16; I2 = 87%) and quadriceps muscle strength (SMD, 0.11; 95% CI, - 0.06, 0.27; P = 0.20; I2 = 25%) compared with the control. In conclusion, NS may be an effective treatment for improving body composition and physical performance in COPD. Future studies should explore the effects of intervention durations, specific NS types, or combined training in patients with COPD and sarcopenia.