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Journal of the International Society of... Sep 2020L-carnitine (LC) is used as a supplement by recreationally-active, competitive and highly trained athletes. This systematic review aims to evaluate the effect of...
BACKGROUND
L-carnitine (LC) is used as a supplement by recreationally-active, competitive and highly trained athletes. This systematic review aims to evaluate the effect of prolonged LC supplementation on metabolism and metabolic modifications.
METHODS
A literature search was conducted in the MEDLINE (via PubMed) and Web of Science databases from the inception up February 2020. Eligibility criteria included studies on healthy human subjects, treated for at least 12 weeks with LC administered orally, with no drugs or any other multi-ingredient supplements co-ingestion.
RESULTS
The initial search retrieved 1024 articles, and a total of 11 studies were finally included after applying inclusion and exclusion criteria. All the selected studies were conducted with healthy human subjects, with supplemented dose ranging from 1 g to 4 g per day for either 12 or 24 weeks. LC supplementation, in combination with carbohydrates (CHO) effectively elevated total carnitine content in skeletal muscle. Twenty-four-weeks of LC supplementation did not affect muscle strength in healthy aged women, but significantly increased muscle mass, improved physical effort tolerance and cognitive function in centenarians. LC supplementation was also noted to induce an increase of fasting plasma trimethylamine-N-oxide (TMAO) levels, which was not associated with modification of determined inflammatory nor oxidative stress markers.
CONCLUSION
Prolonged LC supplementation in specific conditions may affect physical performance. On the other hand, LC supplementation elevates fasting plasma TMAO, compound supposed to be pro-atherogenic. Therefore, additional studies focusing on long-term supplementation and its longitudinal effect on the cardiovascular system are needed.
Topics: Age Factors; Body Composition; Carnitine; Cognition; Dietary Carbohydrates; Dietary Supplements; Energy Metabolism; Exercise; Exercise Tolerance; Humans; Lipid Metabolism; Methylamines; Muscle Proteins; Muscle Strength; Muscle, Skeletal; Obesity; Oxidation-Reduction; Physical Conditioning, Human; Sarcopenia
PubMed: 32958033
DOI: 10.1186/s12970-020-00377-2 -
Nutrition (Burbank, Los Angeles County,... Oct 2022With increasing life expectancy of patients with cystic fibrosis (CF), gastrointestinal manifestations of the disease have been increasingly brought into focus. This was... (Review)
Review
With increasing life expectancy of patients with cystic fibrosis (CF), gastrointestinal manifestations of the disease have been increasingly brought into focus. This was a systematic review of the PubMed database and ongoing phase III clinical trials that aimed to summarize recent (published after June 1 2016) studies reporting the effects of nutritional interventions on anthropometric measures (weight, height, and body mass index) in patients with CF. Two ongoing trials and 40 published studies (18 interventional and 22 observational) were identified. Key results supported the benefits of comprehensive, individualized nutritional plans, high-fat, high-calorie diet including high-quality carbohydrates, and enteric tube feeding (albeit the latter was derived from observational studies only). In contrast, the supplementation of probiotics, lipids, docosahexaenoic, glutathione, or antioxidant-enriched multivitamin appeared to have little effect on anthropometric measures.
Topics: Body Height; Body Mass Index; Cystic Fibrosis; Enteral Nutrition; Humans; Nutritional Status
PubMed: 35816813
DOI: 10.1016/j.nut.2022.111725 -
Nutrients Jan 2023Diabetes disrupts one in six pregnancies, bestowing immediate and long-term health risks to mother and child. Diet and exercise are commonly prescribed to control... (Meta-Analysis)
Meta-Analysis Review
Nutritional and Exercise-Focused Lifestyle Interventions and Glycemic Control in Women with Diabetes in Pregnancy: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.
Diabetes disrupts one in six pregnancies, bestowing immediate and long-term health risks to mother and child. Diet and exercise are commonly prescribed to control dysglycemia, but their effectiveness across sub-populations and types of diabetes (type-1; type-2; or gestational diabetes mellitus, GDM) is uncertain. Therefore, a systematic review and meta-analysis on the effect of diet and/or exercise on glycemia in pregnant women with diabetes was conducted. Random effects models were used to evaluate effect sizes across studies and anticipated confounders (e.g., age, ethnicity, BMI). Of the 4845 records retrieved, 26 studies (8 nutritional supplements, 12 dietary, and 6 exercise interventions) were included. All studies were conducted in patients with GDM. Overall, supplement- and exercise-based interventions reduced fasting glucose (−0.30 mmol/L; 95% CI = −0.55, −0.06; p = 0.02; and 0.10 mmol/L; 95% CI = −0.20, −0.01; p = 0.04); and supplement- and diet-based interventions reduced HOMA-IR (−0.40; 95% CI = −0.58, −0.22; p < 0.001; and −1.15; 95% CI = −2.12, −0.17; p = 0.02). Subgroup analysis by confounders only confirmed marginal changed effect sizes. Our results suggest a favorable role of certain nutritional supplements, diet, and exercise practices on glycemia in women with GDM and underline a lack of evidence in ~20% of other diabetes-related pregnancies (i.e., women with pre-existing diabetes).
Topics: Female; Humans; Pregnancy; Diabetes, Gestational; Diet; Glycemic Control; Life Style; Randomized Controlled Trials as Topic
PubMed: 36678193
DOI: 10.3390/nu15020323 -
Nutrients Oct 2022(1) Background: Whey protein (WP) in combination with resistance training (RT) is beneficial in improving sarcopenic obesity and its damaging effects in older adults,... (Meta-Analysis)
Meta-Analysis
(1) Background: Whey protein (WP) in combination with resistance training (RT) is beneficial in improving sarcopenic obesity and its damaging effects in older adults, while the difference between men and women should be considered while interpreting results. This review aims to investigate WP's efficacy on postmenopausal women with or without RT; (2) Material and Methods: We searched electronic databases including PubMed, EMBASE, and the Cochrane Library from inception to August 2021 for randomized controlled trials that included comparison groups to evaluate WP's efficacy in women aged 55 years and above. The outcomes included body composition, muscular strength, functional capacity, and dietary intake. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were used to estimate the effect of WP. We also performed subgroup analysis with or without RT; (3) Results: We included 14 studies in the systematic review and 10 studies in the meta-analysis. Subgroup analyses showed RT was a major confounder for muscle strength, lean mass, and dietary protein intake (PI). In the RT subgroup, WP supplementation had a significant positive effect on biceps curl strength (BC) (SMD: 0.6805, 95% CI: 0.176, 1.185, : 0%), and lower limb lean-mass (LLLM) (SMD: 1.103, 95% CI: 0.632, 1.574, : 14%). In the subgroup without RT, a significant negative effect on PI (SMD: -0.4225, 95% CI: -0.774, -0.071, : 47%) was observed, while no significant effect on muscle strength or lean mass was revealed. WP supplementation did not show a significantly different effect on fat mass or body weight loss in both the subgroups; (4) Conclusions: In postmenopausal women, WP supplementation only in combination with RT enhances BC and LLLM compared to placebo controls. Without RT, WP has no significant benefit on muscle strength or lean mass.
Topics: Aged; Body Composition; Dietary Proteins; Dietary Supplements; Female; Humans; Male; Muscle Strength; Muscle, Skeletal; Postmenopause; Resistance Training; Whey Proteins
PubMed: 36235862
DOI: 10.3390/nu14194210 -
Nutrition (Burbank, Los Angeles County,... Feb 2021CrossFit (CF) is characterized as a constantly varied, high-intensity, functional movement training program, performed with little or no rest between bouts, combining... (Review)
Review
Effects of diet interventions, dietary supplements, and performance-enhancing substances on the performance of CrossFit-trained individuals: A systematic review of clinical studies.
CrossFit (CF) is characterized as a constantly varied, high-intensity, functional movement training program, performed with little or no rest between bouts, combining strength and endurance exercises, such as running, cycling, rowing, Olympic weightlifting, power weightlifting, and gymnastic-type exercises. Several nutritional strategies are used to improve sports performance of CF practitioners; however, most of them are empirical and lack scientific evidence. Thus, the aim of this review was to determine the effects of diet intervention, dietary supplements, and performance-enhancing substances on exercise-performance parameters of CF practitioners. MEDLINE/PubMed, Web of Science, LILACS, SciELO, and Scopus databases were searched using specific Medical Subject Headings and keywords for clinical studies that enrolled CF athletes in an intervention using diet, dietary supplements, or performance-enhancing substances. Athletic performance was considered as the primary outcome. No other filters were applied. Including grey literature search, 219 studies were identified; however only 14 studies met the eligibility criteria. Two studies evaluated the effects of caffeine supplementation on exercise performance; five studies evaluated high- or low-carbohydrate effects on performance and other parameters. One study verified the effects of multi-ingredient supplementation on CF-specific performance and body composition. One study compared the intake of protein supplements on performance and body composition. Two studies assessed the effect of green tea and (-)-epicatechin on performance and other parameters. One study evaluated the effects of nitrate supplementation on exercise performance. One study investigated the effect of betaine supplementation on body composition and muscle performance. Finally, one study examined the effects of sodium bicarbonate (SB) ingestion on exercise performance and aerobic capacity. Only SB supplementation improved CF performance. These outcomes may have been obtained due to methodological limitations such as small sample size, lack of control over influencing variables, short period of exercise intervention. Despite the popularity and growing evidence about CF, little is known about the relationship between performance-enhancing substances or dietary interventions and CF performance. Given the lack of scientific evidence, new studies with potential ergogenic supplements, a better methodological model, and practical application are required.
Topics: Athletes; Athletic Performance; Caffeine; Diet; Dietary Supplements; Humans; Performance-Enhancing Substances
PubMed: 33051114
DOI: 10.1016/j.nut.2020.110994 -
Nutrients Apr 2023Sarcopenia is a progressive and frequent syndrome among older adults highly related to physical inactivity and malnutrition. Nowadays, it is considered a pathology that... (Review)
Review
Sarcopenia is a progressive and frequent syndrome among older adults highly related to physical inactivity and malnutrition. Nowadays, it is considered a pathology that triggers multiple health complications associated with the loss of muscle mass, strength, autonomy, and quality of life. The objective of the present systematic review was to evaluate the effect of exercise programs combined with dietary supplementation on body composition as the primary outcome. This systematic review was carried out in accordance with the elements considered for planning a systematic review by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and the search was performed in the Scopus, EBSCO, and PubMed databases for the last 10 years. A total of 16 studies met the inclusion criteria and were included in this systematic review. Regular resistance exercise together with daily essential amino acids or whey protein and vitamin D supplementation improve the maintenance or gains in appendiceal/skeletal muscle mass and total lean mass in sarcopenic older adults. The data suggest a synergistic effect not only on the primary outcome, but also on other variables such as strength, speed, stability, and other indicators of quality of life. This systematic review was registered in PROSPERO, ID: CRD42022344284.
Topics: Humans; Aged; Sarcopenia; Muscle Strength; Quality of Life; Dietary Supplements; Body Composition; Resistance Training; Diet; Muscle, Skeletal
PubMed: 37111217
DOI: 10.3390/nu15081998 -
Journal of the American College of... Feb 2021This is an update of the previous 2018 systematic review and meta-analysis of vitamin and mineral supplementation on cardiovascular disease outcomes and all-cause... (Meta-Analysis)
Meta-Analysis
This is an update of the previous 2018 systematic review and meta-analysis of vitamin and mineral supplementation on cardiovascular disease outcomes and all-cause mortality. New randomized controlled trials and meta-analyses were identified by searching the Cochrane library, Medline, and Embase, and data were analyzed using random effects models and classified by the Grading of Recommendations Assessment Development and Evaluation approach. This updated review shows similar findings to the previous report for preventive benefits from both folic acid and B vitamins for stroke and has been graded with moderate quality. No effect was seen for the commonly used multivitamins, vitamin D, calcium, and vitamin C, and an increased risk was seen with niacin (with statin) for all-cause mortality. Conclusive evidence for the benefit of supplements across different dietary backgrounds, when the nutrient is sufficient, has not been demonstrated.
Topics: Cardiovascular Diseases; Diet, Vegetarian; Dietary Supplements; Humans; Stroke; Vitamin B Complex
PubMed: 33509399
DOI: 10.1016/j.jacc.2020.09.619 -
Nutrients Aug 2020Although a cholesterol-lowering diet and the addition of plant sterols and stanols are suggested for the lipid management of children and adults with familial... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Although a cholesterol-lowering diet and the addition of plant sterols and stanols are suggested for the lipid management of children and adults with familial hypercholesterolemia, there is limited evidence evaluating such interventions in this population.
OBJECTIVES
To investigate the impact of cholesterol-lowering diet and other dietary interventions on the incidence or mortality of cardiovascular disease and lipid profile of patients with familial hypercholesterolemia.
SEARCH METHODS
Relevant trials were identified by searching US National Library of Medicine National Institutes of Health Metabolism Trials Register and clinicaltrials.gov.gr using the following terms: diet, dietary, plant sterols, stanols, omega-3 fatty acids, fiber and familial hypercholesterolemia.
SELECTION CRITERIA
Randomized controlled trials evaluating the effect of cholesterol-lowering diet or other dietary interventions in children and adults with familial hypercholesterolemia were included.
DATA COLLECTION AND ANALYSIS
Two authors independently assessed the eligibility of the included trials and their bias risk and extracted the data which was independently verified by other colleagues.
RESULTS
A total of 17 trials were finally included, with a total of 376 participants across 8 comparison groups. The included trials had either a low or unclear bias risk for most of the assessed risk parameters. Cardiovascular incidence or mortality were not evaluated in any of the included trials. Among the planned comparisons regarding patients' lipidemic profile, a significant difference was noticed for the following comparisons and outcomes: omega-3 fatty acids reduced triglycerides (mean difference (MD): -0.27 mmol/L, 95% confidence interval (CI): -0.47 to -0.07, < 0.01) when compared with placebo. A non-significant trend towards a reduction in subjects' total cholesterol (MD: -0.34, 95% CI: -0.68 to 0, mmol/L, = 0.05) and low-density lipoprotein cholesterol (MD: -0.31, 95% CI: -0.61 to 0, mmol/L, = 0.05) was noticed. In comparison with cholesterol-lowering diet, the additional consumption of plant stanols decreased total cholesterol (MD: -0.62 mmol/L, 95% CI: -1.13 to -0.11, = 0.02) and low-density lipoprotein cholesterol (MD: -0.58 mmol/L, 95% CI: -1.08 to -0.09, = 0.02). The same was by plant sterols (MD: -0.46 mmol/L, 95% CI: -0.76 to -0.17, < 0.01 for cholesterol and MD: -0.45 mmol/L, 95% CI: -0.74 to -0.16, < 0.01 for low-density lipoprotein cholesterol). No heterogeneity was noticed among the studies included in these analyses.
CONCLUSIONS
Available trials confirm that the addition of plant sterols or stanols has a cholesterol-lowering effect on such individuals. On the other hand, supplementation with omega-3 fatty acids effectively reduces triglycerides and might have a role in lowering the cholesterol of patients with familial hypercholesterolemia. Additional studies are needed to investigate the efficacy of cholesterol-lowering diet or the addition of soya protein and dietary fibers to a cholesterol-lowering diet in patients with familial hypercholesterolemia.
Topics: Adult; Anticholesteremic Agents; Cardiovascular Diseases; Child; Cholesterol; Cholesterol, LDL; Clinical Trials as Topic; Diet; Dietary Supplements; Fatty Acids, Omega-3; Female; Heart Disease Risk Factors; Humans; Hyperlipoproteinemia Type II; Male; Phytosterols; Triglycerides
PubMed: 32823643
DOI: 10.3390/nu12082436 -
The Cochrane Database of Systematic... Feb 2023Gestational diabetes with onset or first recognition during pregnancy is an increasing problem worldwide. Myo-inositol, an isomer of inositol, is a naturally occurring... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Gestational diabetes with onset or first recognition during pregnancy is an increasing problem worldwide. Myo-inositol, an isomer of inositol, is a naturally occurring sugar commonly found in cereals, corn, legumes and meat. Myo-inositol is one of the intracellular mediators of the insulin signal and correlates with insulin sensitivity in type 2 diabetes. The potential beneficial effect of improving insulin sensitivity suggests that myo-inositol may be useful for women in preventing gestational diabetes. This is an update of a review first published in 2015.
OBJECTIVES
To assess if antenatal dietary supplementation with myo-inositol is safe and effective, for the mother and fetus, in preventing gestational diabetes.
SEARCH METHODS
We searched the Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, WHO ICTRP (17 March 2022) and the reference lists of retrieved studies.
SELECTION CRITERIA
We included published and unpublished randomised controlled trials (RCTs) including cluster-RCTs and conference abstracts, assessing the effects of myo-inositol for the prevention of gestational diabetes in pregnant women. We included studies that compared any dose of myo-inositol, alone or in a combination preparation, with no treatment, placebo or another intervention. Quasi-randomised and cross-over trials were not eligible. We excluded women with pre-existing type 1 or type 2 diabetes.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed studies for inclusion, assessed risk of bias and extracted the data. We checked the data for accuracy. We assessed the certainty of the evidence using the GRADE approach.
MAIN RESULTS
We included seven RCTs (one conducted in Ireland, six conducted in Italy) reporting on 1319 women who were 10 weeks to 24 weeks pregnant at the start of the studies. The studies had relatively small sample sizes and the overall risk of bias was low. For the primary maternal outcomes, meta-analysis showed that myo-inositol may reduce the incidence of gestational diabetes (risk ratio (RR) 0.53, 95% confidence interval (CI) 0.31 to 0.90; 6 studies, 1140 women) and hypertensive disorders of pregnancy (RR 0.34, 95% CI 0.19 to 0.61; 5 studies, 1052 women). However, the certainty of the evidence was low to very low. For the primary neonatal outcomes, only one study measured the risk of a large-for-gestational-age infant and found myo-inositol was associated with both appreciable benefit and harm (RR 1.40, 95% CI 0.65 to 3.02; 1 study, 234 infants; low-certainty evidence). None of the included studies reported on the other primary neonatal outcomes (perinatal mortality, mortality or morbidity composite). For the secondary maternal outcomes, we are unclear about the effect of myo-inositol on weight gain during pregnancy (mean difference (MD) -0.25 kilogram (kg), 95% CI -1.26 to 0.75 kg; 4 studies, 831 women) and perineal trauma (RR 4.0, 95% CI 0.45 to 35.25; 1 study, 234 women) because the evidence was assessed as being very low-certainty. Further, myo-inositol may result in little to no difference in caesarean section (RR 0.91, 95% CI 0.77 to 1.07; 4 studies, 829 women; low-certainty evidence). None of the included studies reported on the other secondary maternal outcomes (postnatal depression and the development of subsequent type 2 diabetes mellitus). For the secondary neonatal outcomes, meta-analysis showed no neonatal hypoglycaemia (RR 3.07, 95% CI 0.90 to 10.52; 4 studies; 671 infants; very low-certainty evidence). However, myo-inositol may be associated with a reduction in the incidence of preterm birth (RR 0.35, 95% CI 0.17 to 0.70; 4 studies; 829 infants). There were insufficient data for a number of maternal and neonatal secondary outcomes, and no data were reported for any of the long-term childhood or adulthood outcomes, or for health service utilisation outcomes.
AUTHORS' CONCLUSIONS
Evidence from seven studies shows that antenatal dietary supplementation with myo-inositol during pregnancy may reduce the incidence of gestational diabetes, hypertensive disorders of pregnancy and preterm birth. Limited data suggest that supplementation with myo-inositol may not reduce the risk of a large-for-gestational-age infant. The current evidence is based on small studies that were not powered to detect differences in outcomes such as perinatal mortality and serious infant morbidity. Six of the included studies were conducted in Italy and one in Ireland, which raises concerns about the lack of generalisability to other settings. There is evidence of inconsistency among doses of myo-inositol, the timing of administration and study population. As a result, we downgraded the certainty of the evidence for many outcomes to low or very low certainty. Further studies for this promising antenatal intervention for preventing gestational diabetes are encouraged and should include pregnant women of different ethnicities and varying risk factors. Myo-inositol at different doses, frequency and timing of administration, should be compared with placebo, diet and exercise, and pharmacological interventions. Long-term follow-up should be considered and outcomes should include potential harms, including adverse effects.
Topics: Adult; Female; Humans; Pregnancy; Diabetes Mellitus, Type 2; Diabetes, Gestational; Dietary Supplements; Hypertension, Pregnancy-Induced; Inositol; Insulin Resistance; Perinatal Death; Premature Birth
PubMed: 36790138
DOI: 10.1002/14651858.CD011507.pub3 -
BJOG : An International Journal of... Oct 2022Calcium supplementation reduces the risk of pre-eclampsia, but questions remain about the dosage to prescribe and who would benefit most. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Calcium supplementation reduces the risk of pre-eclampsia, but questions remain about the dosage to prescribe and who would benefit most.
OBJECTIVES
To evaluate the effectiveness of high (≥1 g/day) and low (<1 g/day) calcium dosing for pre-eclampsia prevention, according to baseline dietary calcium, pre-eclampsia risk and co-interventions, and intervention timing.
SEARCH STRATEGY
CENTRAL, PubMed, Global Index Medicus and CINAHL, from inception to 2 February 2021, clinical trial registries, reference lists and expert input (CRD42018111239).
SELECTION CRITERIA
Randomised controlled trials of calcium supplementation for pre-eclampsia prevention, for women before or during pregnancy. Network meta-analysis (NMA) also included trials of different calcium doses.
DATA COLLECTION AND ANALYSIS
Two independent reviewers extracted published data. The meta-analysis employed random-effects models and the NMA, a Bayesian random-effects model, to obtain direct and indirect effect estimates.
MAIN RESULTS
The meta-analysis included 30 trials (N = 20 445 women), and the NMA to evaluate calcium dosage included 25 trials (N = 15 038). Calcium supplementation prevented pre-eclampsia similarly with a high dose (RR 0.49, 95% CI 0.36-0.66) or a low dose (RR 0.49, 95% CI 0.36-0.65). By NMA, high-dose (vs low-dose) calcium did not differ in effect (RR 0.79, 95% CI 0.43-1.40). Calcium was similarly effective regardless of baseline pre-eclampsia risk, vitamin D co-administration or timing of calcium initiation, but calcium was ineffective among women with adequate average baseline calcium intake.
CONCLUSIONS
Low- and high-dose calcium supplementation are effective for pre-eclampsia prevention in women with low calcium intake. This has implications for population-level implementation where dietary calcium is low, and targeted implementation where average intake is adequate.
TWEETABLE ABSTRACT
A network meta-analysis of 25 trials found that low-dose calcium supplementation (<1 g/day) is as effective as high-dose calcium supplementation (≥1 g/day) in halving the risk of pre-eclampsia when baseline calcium intake is low.
Topics: Bayes Theorem; Calcium; Calcium, Dietary; Dietary Supplements; Female; Humans; Network Meta-Analysis; Pre-Eclampsia; Pregnancy; Prenatal Care
PubMed: 35596262
DOI: 10.1111/1471-0528.17222