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Magnesium Research Nov 2017Increasing evidence supports a role of magnesium (Mg) in skeletal muscle function. However, no systematic review or meta-analysis has summarized data on Mg... (Meta-Analysis)
Meta-Analysis Review
Increasing evidence supports a role of magnesium (Mg) in skeletal muscle function. However, no systematic review or meta-analysis has summarized data on Mg supplementation in relation to muscle fitness in humans. Thus, this study aimed to quantitatively assess the effect of Mg supplementation on muscle fitness. A meta-analysis and systematic review. Medline database and other sources were searched for randomized clinical trials through July 2017. Studies that reported results regarding at least one of the following outcomes: leg strength, knee extension strength, peak torque, muscle power, muscle work, jump, handgrip, bench press weights, resistant exercise, lean mass, muscle mass, muscle strength, walking speed, Repeated Chair Stands, and TGUG were included. Measurements of the association were pooled using a fixed-effects model and expressed as weighted mean differences (WMDs) with 95% confidence intervals (95% CIs). Fourteen randomized clinical trials targeting 3 different populations were identified: athletes or physically active individuals (215 participants; mean age: 24.9 years), untrained healthy individuals (95 participants; mean age: 40.2 years), and elderly or alcoholics (232 participants; mean age: 62.7 years). The beneficial effects of Mg supplementation appeared to be more pronounced in the elderly and alcoholics, but were not apparent in athletes and physically active individuals. The results of the meta-analysis suggested that no significant improvements in the supplementation group were observed regarding isokinetic peak torque extension [WMD = 0.87; 95% CI = (-1.43, 3.18)], muscle strength [WMD = 0.87; 95% CI = (-0.12, 1.86)] or muscle power [WMD = 3.28; 95% CI = (-14.94, 21.50)]. Evidence does not support a beneficial effect of Mg supplementation on muscle fitness in most athletes and physically active individuals who have a relatively high Mg status. But Mg supplementation may benefit individuals with Mg deficiency, such as the elderly and alcoholics.
Topics: Adult; Aged; Alcoholism; Athletes; Dietary Supplements; Exercise; Female; Humans; Magnesium; Male; Muscle Strength
PubMed: 29637897
DOI: 10.1684/mrh.2018.0430 -
Nutrients Feb 2022High carbohydrate intakes are commonly recommended for athletes of various sports, including strength trainees, to optimize performance. However, the effect of... (Review)
Review
High carbohydrate intakes are commonly recommended for athletes of various sports, including strength trainees, to optimize performance. However, the effect of carbohydrate intake on strength training performance has not been systematically analyzed. A systematic literature search was conducted for trials that manipulated carbohydrate intake, including supplements, and measured strength, resistance training or power either acutely or after a diet and strength training program. Studies were categorized as either (1) acute supplementation, (2) exercise-induced glycogen depletion with subsequent carbohydrate manipulation, (3) short-term (2-7 days) carbohydrate manipulation or (4) changes in performance after longer-term diet manipulation and strength training. Forty-nine studies were included: 19 acute, six glycogen depletion, seven short-term and 17 long-term studies. Participants were strength trainees or athletes (39 studies), recreationally active (six studies) or untrained (four studies). Acutely, higher carbohydrate intake did not improve performance in 13 studies and enhanced performance in six studies, primarily in those with fasted control groups and workouts with over 10 sets per muscle group. One study found that a carbohydrate meal improved performance compared to water but not in comparison to a sensory-matched placebo breakfast. There was no evidence of a dose-response effect. After glycogen depletion, carbohydrate supplementation improved performance in three studies compared to placebo, in particular during bi-daily workouts, but not in research with isocaloric controls. None of the seven short-term studies found beneficial effects of carbohydrate manipulation. Longer-term changes in performance were not influenced by carbohydrate intake in 15 studies; one study favored the higher- and one the lower-carbohydrate condition. Carbohydrate intake per se is unlikely to strength training performance in a fed state in workouts consisting of up to 10 sets per muscle group. Performance during higher volumes may benefit from carbohydrates, but more studies with isocaloric control groups, sensory-matched placebos and locally measured glycogen depletion are needed.
Topics: Athletes; Dietary Carbohydrates; Dietary Supplements; Humans; Muscle, Skeletal; Physical Endurance; Resistance Training
PubMed: 35215506
DOI: 10.3390/nu14040856 -
BMJ (Clinical Research Ed.) Feb 2017To assess the overall effect of vitamin D supplementation on risk of acute respiratory tract infection, and to identify factors modifying this effect. Systematic... (Meta-Analysis)
Meta-Analysis Review
To assess the overall effect of vitamin D supplementation on risk of acute respiratory tract infection, and to identify factors modifying this effect. Systematic review and meta-analysis of individual participant data (IPD) from randomised controlled trials. Medline, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, ClinicalTrials.gov, and the International Standard Randomised Controlled Trials Number registry from inception to December 2015. Randomised, double blind, placebo controlled trials of supplementation with vitamin D or vitamin D of any duration were eligible for inclusion if they had been approved by a research ethics committee and if data on incidence of acute respiratory tract infection were collected prospectively and prespecified as an efficacy outcome. 25 eligible randomised controlled trials (total 11 321 participants, aged 0 to 95 years) were identified. IPD were obtained for 10 933 (96.6%) participants. Vitamin D supplementation reduced the risk of acute respiratory tract infection among all participants (adjusted odds ratio 0.88, 95% confidence interval 0.81 to 0.96; P for heterogeneity <0.001). In subgroup analysis, protective effects were seen in those receiving daily or weekly vitamin D without additional bolus doses (adjusted odds ratio 0.81, 0.72 to 0.91) but not in those receiving one or more bolus doses (adjusted odds ratio 0.97, 0.86 to 1.10; P for interaction=0.05). Among those receiving daily or weekly vitamin D, protective effects were stronger in those with baseline 25-hydroxyvitamin D levels <25 nmol/L (adjusted odds ratio 0.30, 0.17 to 0.53) than in those with baseline 25-hydroxyvitamin D levels ≥25 nmol/L (adjusted odds ratio 0.75, 0.60 to 0.95; P for interaction=0.006). Vitamin D did not influence the proportion of participants experiencing at least one serious adverse event (adjusted odds ratio 0.98, 0.80 to 1.20, P=0.83). The body of evidence contributing to these analyses was assessed as being of high quality. Vitamin D supplementation was safe and it protected against acute respiratory tract infection overall. Patients who were very vitamin D deficient and those not receiving bolus doses experienced the most benefit. PROSPERO CRD42014013953.
Topics: Dietary Supplements; Humans; Randomized Controlled Trials as Topic; Respiratory Tract Infections; Vitamin D
PubMed: 28202713
DOI: 10.1136/bmj.i6583 -
Reproductive Sciences (Thousand Oaks,... Jan 2022A patients' increasing interest in dietary modifications as a possible complementary or alternative treatment of endometriosis is observed. Unfortunately, the...
A patients' increasing interest in dietary modifications as a possible complementary or alternative treatment of endometriosis is observed. Unfortunately, the therapeutic potential of dietary interventions is unclear and to date no guidelines to assist physicians on this topic exist. The aim of this study, therefore, was to systematically review the existing studies on the effect of dietary interventions on endometriosis. An electronic-based search was performed in MEDLINE and COCHRANE. We included human and animal studies that evaluated a dietary intervention on endometriosis-associated symptoms or other health outcomes. Studies were identified and coded using standard criteria, and the risk of bias was assessed with established tools relevant to the study design. We identified nine human and 12 animal studies. Out of the nine human studies, two were randomized controlled trials, two controlled studies, four uncontrolled before-after studies, and one qualitative study. All of them assessed a different dietary intervention, which could be classified in one of the following principle models: supplementation with selected dietary components, exclusion of selected dietary components, and complete diet modification. Most of the studies reported a positive effect on endometriosis; they were however characterized by moderate or high-risk bias possibly due to the challenges of conducting dietary intervention trials. According to the available level of evidence, we suggest an evidence-based clinical approach for physicians to use during consultations with their patients. Further well-designed randomized controlled trials are needed to accurately determine the short-term and long-term effectiveness and safety of different dietary interventions.
Topics: Diet; Endometriosis; Female; Humans; Randomized Controlled Trials as Topic
PubMed: 33761124
DOI: 10.1007/s43032-020-00418-w -
Atherosclerosis Feb 2017Epidemiological evidence suggests an association between consumption of tomato products or lycopene and lower risk for cardiovascular diseases (CVD). Our aim was to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND AND AIMS
Epidemiological evidence suggests an association between consumption of tomato products or lycopene and lower risk for cardiovascular diseases (CVD). Our aim was to evaluate the state of the evidence from intervention trials on the effect of consuming tomato products and lycopene on markers of cardiovascular (CV) function. We undertook a systematic review and meta-analysis on the effect of supplementing tomato and lycopene on CV risk factors.
METHODS
Three databases including Medline, Web of science, and Scopus were searched from inception to August 2016. Inclusion criteria were: intervention trials reporting effects of tomato products and lycopene supplementation on CV risk factors among adult subjects >18 years of age. The outcomes of interest included blood lipids (total-, HDL-, LDL-cholesterol, triglycerides, oxidised-LDL), endothelial function (flow-mediated dilation (FMD), pulse wave velocity (PWV)) and blood pressure (BP) inflammatory factors (CRP, IL-6) and adhesion molecules (ICAM-1). Random-effects models were used to determine the pooled effect sizes.
RESULTS
Out of 1189 publications identified, 21 fulfilled inclusion criteria and were meta-analysed. Overall, interventions supplementing tomato were associated with significant reductions in LDL-cholesterol (-0.22 mmol/L; p = 0.006), IL-6 (standardised mean difference -0.25; p = 0.03), and improvements in FMD (2.53%; p = 0.01); while lycopene supplementation reduced systolic-BP (-5.66 mmHg; p = 0.002). No other outcome was significantly affected by these interventions.
CONCLUSIONS
The available evidence on the effects of tomato products and lycopene supplementation on CV risk factors supports the view that increasing the intake of these has positive effects on blood lipids, blood pressure and endothelial function. These results support the development of promising individualised nutritional strategies involving tomatoes to tackle CVD.
Topics: Adult; Biomarkers; Blood Pressure; Cardiovascular Diseases; Carotenoids; Chi-Square Distribution; Diet, Healthy; Dietary Supplements; Endothelium, Vascular; Female; Health Status; Humans; Inflammation Mediators; Lipids; Lycopene; Solanum lycopersicum; Male; Middle Aged; Odds Ratio; Prognosis; Protective Factors; Risk Assessment; Risk Factors; Young Adult
PubMed: 28129549
DOI: 10.1016/j.atherosclerosis.2017.01.009 -
Nutrients Aug 2020Fibromyalgia syndrome (FMS) is characterised by chronic widespread pain alongside fatigue, poor sleep quality and numerous comorbidities. It is estimated to have a...
Fibromyalgia syndrome (FMS) is characterised by chronic widespread pain alongside fatigue, poor sleep quality and numerous comorbidities. It is estimated to have a worldwide prevalence of 1.78%, with a predominance in females. Treatment interventions for fibromyalgia have limited success, leading to many patients seeking alternative forms of treatment, including modifications to their diet and lifestyle. The effectiveness of dietary changes in fibromyalgia has not been widely researched or evaluated. This systematic review identified twenty-two studies, including 18 randomised control trials (RCTs) and four cohort studies which were eligible for inclusion. In total these studies investigated 17 different nutritional interventions. Significant improvements in reported pain were observed for those following a vegan diet, as well as with the low fermentable oligo di-mono-saccharides and polyols (FODMAP) diets. Supplementation with green algae, coenzyme Q10, acetyl-l-carnitine or a combination of vitamin C and E significantly improved measures of pain. Interpretation of these studies was limited due to the frequent poor quality of the study design, the wide heterogeneity between studies, the small sample size and a high degree of bias. Therefore, there is insufficient evidence to recommend any one particular nutritional intervention for the management of fibromyalgia and further research is needed.
Topics: Acetylcarnitine; Ascorbic Acid; Chlorella; Diet, Vegan; Dietary Supplements; Fermented Foods; Fibromyalgia; Humans; Nigella sativa; Pain; Phytotherapy; Quality of Life; Randomized Controlled Trials as Topic; Seeds; Treatment Outcome; Ubiquinone; Vitamin E
PubMed: 32878326
DOI: 10.3390/nu12092664 -
Effects of dietary supplements on athletic performance in elite soccer players: a systematic review.Journal of the International Society of... Dec 2023Dietary supplements are widely used among athletes, and soccer players are no exception. Nevertheless, evidence supporting the use of dietary supplements aiming to... (Review)
Review
Dietary supplements are widely used among athletes, and soccer players are no exception. Nevertheless, evidence supporting the use of dietary supplements aiming to enhance performance in soccer is somewhat contradictory, scarce, or even nonexistent. Thus, the present study aimed to systematically review and synthesize the effects of dietary supplements on athletic performance (e.g. distance covered, sprinting, jump performance) in elite soccer players. Studies enrolling highly trained, elite, and world-class soccer players using dietary supplements were searched in MEDLINE/PubMed, Web of Science, Scopus, and EBSCO databases in June 2022. In total, 1043 studies were identified, and 18 met the eligibility criteria. The studies evaluated the impacts on athletic performance of several dietary supplements, including caffeine, creatine, protein, beverages with carbohydrates and electrolytes, tart cherry juice, nitrate-rich beetroot juice, sodium bicarbonate with minerals, yohimbine, and a proprietary nutraceutical blend. Caffeine supplementation in doses between 3 and 6 mg/kg of body mass may improve jump height and sprint ability, particularly in female players, but individual response to caffeine must be considered. Creatine may improve sprint, agility, and in female players, jump performance. Protein supplementation can improve sprint and jump performance between matches, especially if protein ingested from food is not up to recommendations. Beverages containing carbohydrates and electrolytes can be used as part of the strategies to achieve carbohydrate intake during training and match-days but used alone do not benefit athletic performance. Tart cherry juice might be useful for maintaining athletic performance after matches that produce higher force loss and exercise-induced muscle damage, although polyphenols from the diet might attenuate the effects of tart cherry supplementation. Nitrate-rich beetroot concentrate can attenuate performance decrease in the days following matches. Further investigation with sodium bicarbonate alone is necessary, as supplementation protocols with elite players included other substances. Finally, the available data does not support yohimbine supplementation or the use of Resurgex Plus® to improve athletic performance in elite soccer players. Still, more well-designed research with elite soccer players is needed to improve support and advice regarding the use of dietary supplements for athletic performance enhancement.
Topics: Humans; Female; Soccer; Caffeine; Sodium Bicarbonate; Creatine; Nitrates; Athletic Performance; Dietary Supplements; Electrolytes; Carbohydrates
PubMed: 37462346
DOI: 10.1080/15502783.2023.2236060 -
International Journal of Environmental... Jan 2022Dietary nitrate supplementation is evidenced to induce physiological effects on skeletal muscle function in fast-twitch muscle fibers and may enhance high-intensity... (Review)
Review
Dietary nitrate supplementation is evidenced to induce physiological effects on skeletal muscle function in fast-twitch muscle fibers and may enhance high-intensity exercise performance. An important component of sport-specific skills is the ability to perform explosive movements; however, it is unclear if nitrate supplementation can impact explosive efforts. We examined the existing evidence to determine whether nitrate supplementation improves explosive efforts lasting ≤ 6 s. PubMed, Scopus and Directory of Open Access Journals (DOAJ) were searched for articles using the following search strategy: (nitrate OR nitrite OR beetroot) AND (supplement OR supplementation) AND (explosive OR power OR high intensity OR high-intensity OR sprint* OR "athletic performance"). Out of 810 studies, 18 were eligible according to inclusion criteria. Results showed that 4 of the 10 sprint-type studies observed improved sprint time, power output, and total work in cycling or running, whereas 4 of the 10 resistance-based exercise studies observed improvements to power and velocity of free-weight bench press as well as isokinetic knee extension and flexion at certain angular velocities. These results suggest that nitrate potentially improves explosive exercise performance, but further work is required to clarify the factors influencing the efficacy of nitrate in different exercise modalities.
Topics: Athletic Performance; Dietary Supplements; Double-Blind Method; Explosive Agents; Nitrates; Nitrites
PubMed: 35055584
DOI: 10.3390/ijerph19020762 -
Frontiers in Immunology 2020Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple organ involvement, including the skin, joints, kidneys, lungs, central nervous...
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by multiple organ involvement, including the skin, joints, kidneys, lungs, central nervous system and the haematopoietic system, with a large number of complications. Despite years of study, the etiology of SLE remains unclear; thus, safe and specifically targeted therapies are lacking. In the last 20 years, researchers have explored the potential of nutritional factors on SLE and have suggested complementary treatment options through diet. This study systematically reviews and evaluates the clinical and preclinical scientific evidence of diet and dietary supplementation that either alleviate or exacerbate the symptoms of SLE. For this review, a systematic literature search was conducted using PubMed, Scopus and Google Scholar databases only for articles written in the English language. Based on the currently published literature, it was observed that a low-calorie and low-protein diet with high contents of fiber, polyunsaturated fatty acids, vitamins, minerals and polyphenols contain sufficient potential macronutrients and micronutrients to regulate the activity of the overall disease by modulating the inflammation and immune functions of SLE.
Topics: Animals; Diet; Diet Therapy; Dietary Supplements; Fatty Acids, Unsaturated; Humans; Immunomodulation; Lupus Erythematosus, Systemic; Minerals; Polyphenols
PubMed: 32793202
DOI: 10.3389/fimmu.2020.01477 -
Nutrients May 2020Lactose intolerance (LI) is characterized by the presence of primarily gastrointestinal clinical signs resulting from colonic fermentation of lactose, the absorption of... (Meta-Analysis)
Meta-Analysis
Lactose intolerance (LI) is characterized by the presence of primarily gastrointestinal clinical signs resulting from colonic fermentation of lactose, the absorption of which is impaired due to a deficiency in the lactase enzyme. These clinical signs can be modified by several factors, including lactose dose, residual lactase expression, concurrent ingestion of other dietary components, gut-transit time, and enteric microbiome composition. In many of individuals with lactose malabsorption, clinical signs may be absent after consumption of normal amounts of milk or, in particular, dairy products (yogurt and cheese), which contain lactose partially digested by live bacteria. The intestinal microbiota can be modulated by biotic supplementation, which may alleviate the signs and symptoms of LI. This systematic review summarizes the available evidence on the influence of prebiotics and probiotics on lactase deficiency and LI. The literature search was conducted using the MEDLINE (via PUBMED) and SCOPUS databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and included randomized controlled trials. For each study selected, the risk of bias was assessed following the Cochrane Collaboration methodology. Our findings showed varying degrees of efficacy but an overall positive relationship between probiotics and LI in relation to specific strains and concentrations. Limitations regarding the wide heterogeneity between the studies included in this review should be taken into account. Only one study examined the benefits of prebiotic supplementation and LI. So further clinical trials are needed in order to gather more evidence.
Topics: Abdominal Pain; Animals; Databases, Factual; Diarrhea; Diet; Flatulence; Food, Fortified; Gastrointestinal Microbiome; Humans; Lactase; Lactose; Lactose Intolerance; Milk; Prebiotics; Probiotics; Vomiting
PubMed: 32443748
DOI: 10.3390/nu12051487