-
Cureus Dec 2023With increasing life expectancy, the quest for skin rejuvenation has gained prominence among individuals of diverse age groups. The popularity of nutricosmetics, notably... (Review)
Review
With increasing life expectancy, the quest for skin rejuvenation has gained prominence among individuals of diverse age groups. The popularity of nutricosmetics, notably dietary supplements, has garnered significant attention in recent years. Many scientific investigations have amassed compelling evidence highlighting the positive impact of hydrolyzed collagen supplementation in mitigating the visible signs of skin aging. This study aims to know the powerful effect of hydrolyzed collagen on the skin. This research method is to conduct a systematic review followed by a meta-analysis of the clinical trial focusing on randomized, double-blind, and controlled trials that examined the oral consumption of hydrolyzed collagen and reported outcomes related to skin aging, wrinkles, moisture levels, elasticity, and firmness. The selected articles from CENTRAL, PubMed, Google Scholar, and ScienceDirect databases were published from 2017 to 2023. The subsequent meta-analysis, comprising 14 distinct studies and a collective cohort of 967 participants, revealed encouraging findings favoring hydrolyzed collagen supplementation. It consistently demonstrated substantial enhancements in skin moisture levels and elasticity compared to the placebo group, a trend robustly corroborated by subgroup analysis. These compelling findings underscore the effectiveness of a 12-week regimen of hydrolyzed collagen supplementation in revitalizing the skin by augmenting its hydration and elasticity.
PubMed: 38192916
DOI: 10.7759/cureus.50231 -
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 Apr 2023According to reports, supplementation with appropriate doses of taurine may help to reduce visual fatigue. Presently, some progress has been made in research related to... (Review)
Review
According to reports, supplementation with appropriate doses of taurine may help to reduce visual fatigue. Presently, some progress has been made in research related to taurine in eye health, but the lack of systematic summaries has led to the neglect of its application in the relief of visual fatigue. This paper, therefore, provides a systematic review of the sources of taurine, including the endogenous metabolic and exogenous dietary pathways, as well as a detailed review of the distribution and production of exogenous taurine. The physiological mechanisms underlying the production of visual fatigue are summarized and the research progress of taurine in relieving visual fatigue is reviewed, including the safety of consumption and the mechanism of action in relieving visual fatigue, in order to provide some reference basis and inspiration for the development and application of taurine in functional foods for relieving visual fatigue.
Topics: Humans; Taurine; Asthenopia; Diet; Functional Food; Dietary Supplements
PubMed: 37111062
DOI: 10.3390/nu15081843 -
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 -
Clinical Nutrition ESPEN Apr 2019Breast cancer (BC) is the most common malignancy among women in the US. Vitamin D status and intakes are thought to be inversely associated with BC occurrence. (Meta-Analysis)
Meta-Analysis
CONTEXT
Breast cancer (BC) is the most common malignancy among women in the US. Vitamin D status and intakes are thought to be inversely associated with BC occurrence.
OBJECTIVES
In our systematic review and meta-analysis, we evaluated evidence linking serum 25(OH)D (both in serum and diet) with breast cancer (BC) occurrence.
DATA SOURCES AND EXTRACTION
Only observational studies from databases such as PubMed and Cochrane (January 1st 2000 through March 15th, 2018) were included using PRISMA guidelines. Publication bias and consistency upon replication were assessed, while harmonizing risk ratios (RR, 95% CI) of BC, per fixed increment of 5 exposures [10 ng/mL of 25(OH)D; 100 IU/d for total/dietary vitamin D intakes; vitamin D deficiency; supplement use). RRs were pooled using random effect models.
DATA ANALYSIS
Pooled findings from 22 studies suggested a net direct association between 25(OH)D deficiency and BC, with RR = 1.91, 95% CI: 1.51-2.41, P < 0.001). Total vitamin D intake (RR = 0.99, 95% CI: 0.97-1.00, P = 0.022, per 100 IU/d) and supplemental vitamin D (RR = 0.97, 95% CI:0.95-1.00, P = 0.026) were inversely associated with BC. No evidence of publication bias was found; all 5 exposures of interest were consistent upon replication.
CONCLUSIONS
25(OH)D deficiency was directly related to BC while total vitamin D and supplemental vitamin D intakes had an inverse relationship with this outcome. Randomized clinical trials are warranted pending further evidence from primary meta-analyses of observational studies.
Topics: Breast Neoplasms; Dietary Supplements; Female; Humans; Nutritional Status; Observational Studies as Topic; Odds Ratio; United States; Vitamin D; Vitamin D Deficiency; Vitamins
PubMed: 30904218
DOI: 10.1016/j.clnesp.2018.12.085 -
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 -
International Journal of Environmental... Apr 2020Creatine monohydrate is a nutritional supplement often consumed by athletes in anaerobic sports. Creatine is naturally found in most meat products; therefore,...
BACKGROUND
Creatine monohydrate is a nutritional supplement often consumed by athletes in anaerobic sports. Creatine is naturally found in most meat products; therefore, vegetarians have reduced creatine stores and may benefit from supplementation.
OBJECTIVE
to determine the effects of creatine supplementation on vegetarians.
DATA SOURCES
PubMed and SPORTDiscus. Eligibility criteria: Randomized controlled trials (parallel group, cross-over studies) or prospective studies.
PARTICIPANTS
Vegetarians.
INTERVENTION
Creatine supplementation. Study appraisal and synthesis: A total of 64 records were identified, and eleven full-text articles (covering nine studies) were included in this systematic review.
RESULTS
Creatine supplementation in vegetarians increased total creatine, creatine, and phosphocreatine concentrations in vastus lateralis and gastrocnemius muscle, plasma, and red blood cells, often to levels greater than omnivores. Creatine supplementation had no effect on brain levels of phosphocreatine. Creatine supplementation increased lean tissue mass, type II fiber area, insulin-like growth factor-1, muscular strength, muscular endurance, Wingate mean power output, and brain function (memory and intelligence) in vegetarian participants. Studies were mixed on whether creatine supplementation improved exercise performance in vegetarians to a greater extent compared to omnivores.
LIMITATIONS
Studies that were reviewed had moderate-high risk of bias.
CONCLUSIONS
Overall, it appears vegetarian athletes are likely to benefit from creatine supplementation.
Topics: Athletes; Cognition; Creatine; Diet, Vegetarian; Dietary Supplements; Humans; Memory; Physical Fitness; Prospective Studies; Vegetarians
PubMed: 32349356
DOI: 10.3390/ijerph17093041 -
Journal of the International Society of... 2022Previous studies have suggested that beta-alanine supplementation may benefit exercise performance, but current evidence regarding its effects on body composition... (Meta-Analysis)
Meta-Analysis
PURPOSE
Previous studies have suggested that beta-alanine supplementation may benefit exercise performance, but current evidence regarding its effects on body composition remains unclear. This systematic review and meta-analysis aimed to investigate the effects of beta-alanine supplementation on body composition indices.
METHODS
Online databases, including PubMed/Medline, Scopus, Web of Science, and Embase, were searched up to April 2021 to retrieve randomized controlled trials (RCTs), which examined the effect of beta-alanine supplementation on body composition indices. Meta-analyses were carried out using a random-effects model. The I index was used to assess the heterogeneity of RCTs.
RESULTS
Among the initial 1413 studies that were identified from electronic databases search, 20 studies involving 492 participants were eligible. Pooled effect size from 20 studies indicated that beta-alanine supplementation has no effect on body mass (WMD: -0.15 kg; 95% CI: -0.78 to 0.47; = 0.631, I = 0.0%, = 0.998), fat mass (FM) (WMD: -0.24 kg; 95% CI: -1.16 to 0.68; = 0.612, I = 0.0%, = 0.969), body fat percentage (BFP) (WMD: -0.06%; 95% CI: -0.53 to 0.40; = 0.782, I = 0.0%, = 0.936), and fat-free mass (FFM) (WMD: 0.05 kg; 95% CI: -0.71 to 0.82; = 0.889, I = 0.0%, = 0.912). Subgroup analyses based on exercise type (resistance training [RT], endurance training [ET], and combined training [CT]), study duration (<8 and ≥8 weeks), and beta-alanine dosage (<6 and ≥6 g/d) demonstrated similar results. Certainty of evidence across outcomes ranged from low to moderate.
CONCLUSIONS
This meta-analysis study suggests that beta-alanine supplementation is unlikely to improve body composition indices regardless of supplementation dosage and its combination with exercise training. No studies have examined the effect of beta-alanine combined with both diet and exercise on body composition changes as the primary variable. Therefore, future studies examining the effect of the combination of beta-alanine supplementation with a hypocaloric diet and exercise programs are warranted.
Topics: Body Composition; Dietary Supplements; Exercise; Humans; beta-Alanine
PubMed: 35813845
DOI: 10.1080/15502783.2022.2079384 -
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 -
The American Journal of Clinical... Dec 2012Protein ingestion after a single bout of resistance-type exercise stimulates net muscle protein accretion during acute postexercise recovery. Consequently, it is... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Protein ingestion after a single bout of resistance-type exercise stimulates net muscle protein accretion during acute postexercise recovery. Consequently, it is generally accepted that protein supplementation is required to maximize the adaptive response of the skeletal muscle to prolonged resistance-type exercise training. However, there is much discrepancy in the literature regarding the proposed benefits of protein supplementation during prolonged resistance-type exercise training in younger and older populations.
OBJECTIVE
The objective of the study was to define the efficacy of protein supplementation to augment the adaptive response of the skeletal muscle to prolonged resistance-type exercise training in younger and older populations.
DESIGN
A systematic review of interventional evidence was performed through the use of a random-effects meta-analysis model. Data from the outcome variables fat-free mass (FFM), fat mass, type I and II muscle fiber cross-sectional area, and 1 repetition maximum (1-RM) leg press strength were collected from randomized controlled trials (RCTs) investigating the effect of dietary protein supplementation during prolonged (>6 wk) resistance-type exercise training.
RESULTS
Data were included from 22 RCTs that included 680 subjects. Protein supplementation showed a positive effect for FFM (weighted mean difference: 0.69 kg; 95% CI: 0.47, 0.91 kg; P < 0.00001) and 1-RM leg press strength (weighted mean difference: 13.5 kg; 95% CI: 6.4, 20.7 kg; P < 0.005) compared with a placebo after prolonged resistance-type exercise training in younger and older subjects.
CONCLUSION
Protein supplementation increases muscle mass and strength gains during prolonged resistance-type exercise training in both younger and older subjects.
Topics: Aging; Dietary Proteins; Dietary Supplements; Humans; Muscle Development; Muscle Strength; Muscle, Skeletal; Randomized Controlled Trials as Topic; Resistance Training
PubMed: 23134885
DOI: 10.3945/ajcn.112.037556