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1.
Mol Cell ; 69(6): 923-937.e8, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29547721

RESUMO

Dietary supplements such as vitamins and minerals are widely used in the hope of improving health but may have unidentified risks and side effects. In particular, a pathogenic link between dietary supplements and specific oncogenes remains unknown. Here we report that chondroitin-4-sulfate (CHSA), a natural glycosaminoglycan approved as a dietary supplement used for osteoarthritis, selectively promotes the tumor growth potential of BRAF V600E-expressing human melanoma cells in patient- and cell line-derived xenograft mice and confers resistance to BRAF inhibitors. Mechanistically, chondroitin sulfate glucuronyltransferase (CSGlcA-T) signals through its product CHSA to enhance casein kinase 2 (CK2)-PTEN binding and consequent phosphorylation and inhibition of PTEN, which requires CHSA chains and is essential to sustain AKT activation in BRAF V600E-expressing melanoma cells. However, this CHSA-dependent PTEN inhibition is dispensable in cancer cells expressing mutant NRAS or PI3KCA, which directly activate the PI3K-AKT pathway. These results suggest that dietary supplements may exhibit oncogene-dependent pro-tumor effects.


Assuntos
Carcinógenos/toxicidade , Transformação Celular Neoplásica/genética , Sulfatos de Condroitina/toxicidade , Suplementos Nutricionais/toxicidade , Melanoma/induzido quimicamente , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/induzido quimicamente , Animais , Antinematódeos/farmacologia , Caseína Quinase II/metabolismo , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , GTP Fosfo-Hidrolases/genética , Células HEK293 , Células HT29 , Humanos , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Melanoma/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos Transgênicos , Células NIH 3T3 , Proteínas Nucleares/genética , PTEN Fosfo-Hidrolase/antagonistas & inibidores , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/genética , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Annu Rev Nutr ; 43: 179-197, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37196365

RESUMO

Precise dietary assessment is critical for accurate exposure classification in nutritional research, typically aimed at understanding how diet relates to health. Dietary supplement (DS) use is widespread and represents a considerable source of nutrients. However, few studies have compared the best methods to measure DSs. Our literature review on the relative validity and reproducibility of DS instruments in the United States [e.g., product inventories, questionnaires, and 24-h dietary recalls (24HR)] identified five studies that examined validity (n = 5) and/or reproducibility (n = 4). No gold standard reference method exists for validating DS use; thus, each study's investigators chose the reference instrument used to measure validity. Self-administered questionnaires agreed well with 24HR and inventory methods when comparing the prevalence of commonly used DSs. The inventory method captured nutrient amounts more accurately than the other methods. Reproducibility (over 3 months to 2.4 years) of prevalence of use estimates on the questionnaires was acceptable for common DSs. Given the limited body of research on measurement error in DS assessment, only tentative conclusions on these DS instruments can be drawn at present. Further research is critical to advancing knowledge in DS assessment for research and monitoring purposes.


Assuntos
Dieta , Suplementos Nutricionais , Humanos , Estados Unidos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Nutrientes
3.
BMC Cancer ; 24(1): 591, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750410

RESUMO

BACKGROUND: There is little evidence that dietary supplements are beneficial for patients with breast cancer; therefore, they are usually not recommended by treatment guidelines. The aim of the present analysis was to assess the prevalence of dietary supplement (DS) intake among women before and after a breast cancer diagnosis. METHODS: Participants in the SUCCESS C lifestyle intervention study, a randomized controlled trial in women with newly diagnosed intermediate- to high-risk breast cancer, completed two questionnaires on dietary supplement intake 24 months (QS1) and 48 months (QS2) after beginning the lifestyle intervention. The study was registered on 12.17.2008 under the EU Clinical Trials Register https://www.clinicaltrialsregister.eu/ , trial registration number: 2008-005453-38. The questionnaires collected data on DS intake during the 5-year period prediagnosis (QS1) and in the period postdiagnosis (QS2). Multivariate logistic regression models were fitted to examine differences in DS intake between the two intervention groups. The groups were then pooled to examine differences in DS use between the prediagnostic and postdiagnostic period. RESULTS: A total of 320 questionnaires from 58.5% of intervention group completers and 416 questionnaires from 46.6% of low-level intervention group completers were included in the analysis. Overall, 20.2% of all respondents reported taking DS prior to their diagnosis. After a cancer diagnosis, the percentage of women taking DS significantly increased to 56.4% (p for time effect < 0.0001). No differences in DS intake between the intervention groups were observed. Single or combined preparations of vitamins and minerals/trace elements were the most frequently reported supplements. Notably, a 9-fold increase in vitamin D intake was reported postdiagnosis, where the proportion of women increased from 3.8 to 34.5%. CONCLUSION: A 3-fold increase in the reported intake of dietary supplements was seen in women after a breast cancer diagnosis. These observations underscore the need to incorporate patient education surrounding the use of dietary supplements in a treatment care plan, particularly addressing the negligible benefits as well as the potential risks and treatment interactions.


Assuntos
Neoplasias da Mama , Suplementos Nutricionais , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto , Idoso , Estilo de Vida
4.
Eur J Vasc Endovasc Surg ; 67(4): 570-582, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38013062

RESUMO

OBJECTIVE: Large abdominal aortic aneurysms (AAAs) present a significant mortality risk. While numerous medical interventions have been proposed, no drugs have convincingly reduced AAA progression, rupture rates, or repair risk. This systematic review and meta-analysis aimed to assess the impact of re-purposed drugs or dietary supplements on slowing expansion rates, reducing the risk of rupture, or minimising the risk of repair for individuals with AAA. METHODS: A systematic search was conducted in five databases. Both observational studies and randomised controlled trials were included. Unpublished data from two screening trials were incorporated. Risk of bias was assessed using the Newcastle-Ottawa scale and revised Cochrane risk of bias tool. Meta-analyses were performed for each identified drug subclass and were stratified by overall risk of bias. Results were reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Of 7 484 screened studies, 39 met the inclusion criteria. No studies on dietary supplements were included. A total of 84 cohorts were derived from the included studies, and twelve distinct drug groups underwent meta-analyses. Two drug groups, metformin and statins, were statistically significant in slowing AAA growth. No low risk of bias studies were included for these two drug groups, and the results had very high heterogeneity (I2 > 80%). Both groups had a GRADE certainty of very low. Metformin, excluding high risk of bias studies, presented an estimated mean growth difference of AAA diameter between users and non-users of -0.73 mm/year, whilst statins had an overall estimated mean difference of -0.84 mm/year. CONCLUSION: This systematic review and meta-analysis suggests that metformin and statins may provide some effect in slowing AAA progression. However, no definitive evidence was found for any of the investigated drugs included in this study. Further research is needed to identify effective medical treatments for AAA progression with more robust methodology.


Assuntos
Aneurisma da Aorta Abdominal , Inibidores de Hidroximetilglutaril-CoA Redutases , Metformina , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/tratamento farmacológico
5.
Br J Nutr ; 131(3): 461-473, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-37641937

RESUMO

Rhodiola rosea (RR) is a plant whose bioactive components may function as adaptogens, thereby increasing resistance to stress and improving overall resilience. Some of these effects may influence exercise performance and adaptations. Based on studies of rodents, potential mechanisms for the ergogenic effects of RR include modulation of energy substrate stores and use, reductions in fatigue and muscle damage and altered antioxidant activity. At least sixteen investigations in humans have explored the potential ergogenicity of RR. These studies indicate acute RR supplementation (∼200 mg RR containing ∼1 % salidroside and ∼3 % rosavin, provided 60 min before exercise) may prolong time-to-exhaustion and improve time trial performance in recreationally active males and females, with limited documented benefits of chronic supplementation. Recent trials providing higher doses (∼1500 to 2400 mg RR/d for 4­30 d) have demonstrated ergogenic effects during sprints on bicycle ergometers and resistance training in trained and untrained adults. The effects of RR on muscle damage, inflammation, energy system modulation, antioxidant activity and perceived exertion are presently equivocal. Collectively, it appears that adequately dosed RR enhances dimensions of exercise performance and related outcomes for select tasks. However, the current literature does not unanimously show that RR is ergogenic. Variability in supplementation dose and duration, concentration of bioactive compounds, participant characteristics, exercise tests and statistical considerations may help explain these disparate findings. Future research should build on the longstanding use of RR and contemporary clinical trials to establish the conditions in which supplementation facilitates exercise performance and adaptations.


Assuntos
Substâncias para Melhoria do Desempenho , Rhodiola , Masculino , Adulto , Feminino , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Antioxidantes/farmacologia , Rhodiola/química , Substâncias para Melhoria do Desempenho/farmacologia , Exercício Físico/fisiologia
6.
Eur J Nutr ; 63(1): 323-335, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37874350

RESUMO

PURPOSE: The primary aim of this study was to examine whether a glycine-rich collagen peptides (CP) supplement could enhance sleep quality in physically active men with self-reported sleep complaints. METHODS: In a randomized, crossover design, 13 athletic males (age: 24 ± 4 years; training volume; 7 ± 3 h·wk1) with sleep complaints (Athens Insomnia Scale, 9 ± 2) consumed CP (15 g·day1) or a placebo control (CON) 1 h before bedtime for 7 nights. Sleep quality was measured with subjective sleep diaries and actigraphy for 7 nights; polysomnographic sleep and core temperature were recorded on night 7. Cognition, inflammation, and endocrine function were measured on night 7 and the following morning. Subjective sleepiness and fatigue were measured on all 7 nights. The intervention trials were separated by ≥ 7 days and preceded by a 7-night familiarisation trial. RESULTS: Polysomnography showed less awakenings with CP than CON (21.3 ± 9.7 vs. 29.3 ± 13.8 counts, respectively; P = 0.028). The 7-day average for subjective awakenings were less with CP vs. CON (1.3 ± 1.5 vs. 1.9 ± 0.6 counts, respectively; P = 0.023). The proportion of correct responses on the baseline Stroop cognitive test were higher with CP than CON (1.00 ± 0.00 vs. 0.97 ± 0.05 AU, respectively; P = 0.009) the morning after night 7. There were no trial differences in core temperature, endocrine function, inflammation, subjective sleepiness, fatigue and sleep quality, or other measures of cognitive function or sleep (P > 0.05). CONCLUSION: CP supplementation did not influence sleep quantity, latency, or efficiency, but reduced awakenings and improved cognitive function in physically active males with sleep complaints.


Assuntos
Privação do Sono , Sonolência , Adulto , Humanos , Masculino , Adulto Jovem , Cognição , Fadiga/tratamento farmacológico , Fadiga/psicologia , Inflamação , Sono/fisiologia , Privação do Sono/tratamento farmacológico , Estudos Cross-Over
7.
J Toxicol Environ Health A ; 87(6): 245-265, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38115604

RESUMO

The consumption of dietary supplements to enhance physical performance has increased significantly in the last century, especially thermogenic pre-workout supplements. Nevertheless, this industry has faced criticism for inadequate safety measures surveillance in regulatory issues regarding their products. The aims of our study were to investigate two pre-workout supplements with respect to (1) mutagenicity utilizing Salmonella/microsome assay; (2) genotoxicity employing cytokinesis-block micronucleus (CBMN) assay protocols; and (3) hepatocytoxicity using WST cell proliferation, activities of lactate dehydrogenase (LDH) and alkaline phosphatase using human liver carcinoma (HepG2) and mouse fibroblast (F C3H) cells. Oxidative stress was determined through glutathione (GSH) measurement and in silico for predictions of pharmacokinetics and toxicity for the most abundant isolated substances present in these supplements. Both supplements induced mutagenicity in all examined bacterial strains, especially in the presence of exogenous metabolism. Further, tested supplements significantly elevated the formation of micronuclei (MN) as well as other cellular phenomena. Concentration- and time-dependent curves were observed for hepatotoxicity in both studied cell lines. In addition, both supplements decreased levels of intracellular and extracellular GSH. In silico predictions showed that the isolated individual compounds failed to induce the observed outcomes. Our findings provide contributions to the molecular mechanisms underlying two pre-workout supplement-induced toxicity and the need for surveillance.


Assuntos
Aminas , Cafeína , Suplementos Nutricionais , Camundongos , Animais , Humanos , Cafeína/farmacologia , Camundongos Endogâmicos C3H , Suplementos Nutricionais/toxicidade , Estresse Oxidativo , Glutationa , Mutagênicos/toxicidade , Dano ao DNA
8.
J Appl Toxicol ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724177

RESUMO

Dietary supplements containing usnic acid have been increasingly marketed for weight loss over the past decades, even though incidences of severe hepatotoxicity and acute liver failure due to their overuse have been reported. To date, the toxic mechanism of usnic acid-induced liver injury at the molecular level still remains to be fully elucidated. Here, we conducted a transcriptomic study on usnic acid using a novel in vitro hepatotoxicity model employing human induced pluripotent stem cell (iPSC)-derived hepatocytes. Treatment with 20 µM usnic acid for 24 h caused 4272 differentially expressed genes (DEGs) in the cells. Ingenuity Pathway Analysis (IPA) based on the DEGs and gene set enrichment analysis (GSEA) using the whole transcriptome expression data concordantly revealed several signaling pathways and biological processes that, when taken together, suggest that usnic acid caused oxidative stress and DNA damage in the cells, which further led to cell cycle arrest and eventually resulted in cell death through apoptosis. These transcriptomic findings were subsequently corroborated by a variety of cellular assays, including reactive oxygen species (ROS) generation and glutathione (GSH) depletion, DNA damage (pH2AX detection and 8-hydroxy-2'-deoxyguanosine [8-OH-dg] assay), cell cycle analysis, and caspase 3/7 activity. Collectively, the results of the current study accord with previous in vivo and in vitro findings, provide further evidence that oxidative stress-caused DNA damage contributes to usnic acid-induced hepatotoxicity, shed new light on molecular mechanisms of usnic acid-induced hepatotoxicity, and demonstrate the usefulness of iPSC-derived hepatocytes as an in vitro model for hepatotoxicity testing and prediction.

9.
Scand J Prim Health Care ; 42(1): 16-28, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37982720

RESUMO

OBJECTIVE: The use of dietary supplements (DS) may cause harm through direct and indirect effects. Patients with dementia may be particularly vulnerable. This study aims to explore general practitioners' (GPs') experiences with DS use by these patients, the GPs perceived responsibilities, obstacles in taking on this responsibility, their attitudes toward DS, and suggestions for improvements to safeguard the use of DS in this patient group. DESIGN: Qualitative individual interview study conducted February - December 2019. Data were analysed using systematic text condensation. SETTING: Primary healthcare clinics in Norway. SUBJECTS: Fourteen Norwegian GPs. FINDINGS: None of the informants were dismissive of patients using DS. They were aware of the possible direct risks and had observed them in patients. Most GPs showed little awareness of potential indirect risks to patients with dementia who use DS. They acknowledged the need for caretaking of these patients. Although there were differences in practice styles, most of the GPs wished to help their patients safeguarding DS use but found it difficult due to the lack of quality assurance of product information. Furthermore, there were no effective ways for the GPs to document DS use in the patients' records. Several suggestions for improvement were given by the GPs, such as increased attention from GPs, inclusion of DS in the prescription software, and stricter regulatory systems for DS from the authorities. CONCLUSION: The GPs had initially little awareness of this safety risk, but there were differences in practice style and attitudes towards DS. The GPs did not perceive themselves as main responsible for safe use of DS in patient with dementia. The most important reason to disclaim responsibility was lack of information about the products. One suggestion for improvement was better integration of DS in patients' medical record.


Currently, little is known about general practitioners (GPs) caretaking of patients with dementia who use dietary supplements (DS). Our study showed that:The GPs in this study showed little awareness of the potential safety risk that DS use may represent for patients with dementia.Several obstacles in the treatment setting and in the regulation of DS make it difficult for the GPs to assume full responsibility for patients with dementia who use DS.Lack of evidence about DS safety and effect adds to professional uncertainty and may cause frustration or reluctance to address the issue.


Assuntos
Demência , Clínicos Gerais , Humanos , Pesquisa Qualitativa , Atitude do Pessoal de Saúde , Suplementos Nutricionais
10.
Phytother Res ; 38(2): 1071-1088, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38168043

RESUMO

A sudden outbreak of the COVID-19 pandemic was a big blow to the world community on every level. Created by a novel coronavirus, SARS-CoV-2, which was previously unknown to the human immune system. The expert opinion almost immediately united on the fact that the most effective way of fighting the pandemic would be by building immunity artificially via a mass immunization program. However, it took about a year for the approval of the first vaccine against COVID-19. In the meantime, a big part of the general population started adapting nutritious diet plans and dietary supplements to boost natural immunity as a potential prophylactic strategy against SARS-CoV-2 infection. Whether they originate from mainstream medicine, such as synthetic supplements, or traditional herbal remedies in the form of single or poly-herbs, these supplements may comprise various components that exhibit immunomodulatory, anti-inflammatory, antioxidant, and antimicrobial characteristics. There is a substantial body of predictions and expert opinions suggesting that enhancing one's diet with dietary supplements containing additional nutrients and bioactive compounds like vitamins, minerals, amino acids, fatty acids, phytochemicals, and probiotics can enhance the immune system's ability to develop resistance against COVID-19, although none of them have any conclusive evidence nor officially recommended by World Health Organization (WHO). The current review critically acclaims the gap between public perception-based preference and real evidence-based study to weigh the actual benefit of dietary supplements in relation to COVID-19 prevention and management.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Pandemias/prevenção & controle , Vacinas contra COVID-19 , Suplementos Nutricionais
11.
Int J Food Sci Nutr ; 75(4): 349-368, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38659110

RESUMO

This review aims to analyse the efficacy of dietary supplements in reducing plasma cholesterol levels. Focusing on evidence from meta-analyses of randomised controlled clinical trials, with an emphasis on potential mechanisms of action as supported by human, animal, and cell studies. Certain dietary supplements including phytosterols, berberine, viscous soluble dietary fibres, garlic supplements, soy protein, specific probiotic strains, and certain polyphenol extracts could significantly reduce plasma total and low-density lipoprotein (LDL) cholesterol levels by 3-25% in hypercholesterolemic patients depending on the type of supplement. They tended to be more effective in reducing plasma LDL cholesterol level in hypercholesterolemic individuals than in normocholesterolemic individuals. These supplements worked by various mechanisms, such as enhancing the excretion of bile acids, inhibiting the absorption of cholesterol in the intestines, increasing the expression of hepatic LDL receptors, suppressing the activity of enzymes involved in cholesterol synthesis, and activating the adenosine monophosphate-activated protein kinase signalling pathway.


Assuntos
Anticolesterolemiantes , LDL-Colesterol , Suplementos Nutricionais , Hipercolesterolemia , Humanos , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/dietoterapia , Anticolesterolemiantes/farmacologia , Anticolesterolemiantes/uso terapêutico , LDL-Colesterol/sangue , Colesterol/sangue , Animais , Fitosteróis/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Probióticos/farmacologia , Probióticos/uso terapêutico , Fibras na Dieta/farmacologia , Receptores de LDL/metabolismo , Berberina/farmacologia , Berberina/uso terapêutico , Alho
12.
Int J Mol Sci ; 25(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474096

RESUMO

Aflatoxins are harmful natural contaminants found in foods and are known to be hepatotoxic. However, recent studies have linked chronic consumption of aflatoxins to nephrotoxicity in both animals and humans. Here, we conducted a systematic review of active compounds, crude extracts, herbal formulations, and probiotics against aflatoxin-induced renal dysfunction, highlighting their mechanisms of action in both in vitro and in vivo studies. The natural products and dietary supplements discussed in this study alleviated aflatoxin-induced renal oxidative stress, inflammation, tissue damage, and markers of renal function, mostly in animal models. Therefore, the information provided in this review may improve the management of kidney disease associated with aflatoxin exposure and potentially aid in animal feed supplementation. However, future research is warranted to translate the outcomes of this study into clinical use in kidney patients.


Assuntos
Aflatoxinas , Produtos Biológicos , Nefropatias , Animais , Humanos , Aflatoxinas/toxicidade , Aflatoxina B1/toxicidade , Suplementos Nutricionais
13.
Plant Foods Hum Nutr ; 79(1): 90-97, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38060143

RESUMO

Global population growth poses a threat to sustainable development. Meanwhile, the use of plant proteins as healthy and sustainable alternatives to animal proteins needs further research. Therefore, this investigation was designed to study the nutritive, structural, and thermal properties of isolated protein fractions from different legumes, i.e., faba bean (FPI), soybean (SPI), and lupine (LPI). As a prospective plant-based protein powder, an equal mixture (MPI) of the three prior legume samples was formulated to study its properties compared to each sole sample. The alkaline extraction and isoelectric precipitation (AE-IP) technique was used for protein isolation. Results showed that all protein isolates had reasonable levels of protein with maximum protein content in SPI (96.15%). The MPI sample, however, came out on top in terms of amino acid profile followed by FBI. Compared to SPI and LPI, it had the highest isoleucine content and higher methionine, valine, leucine, phenylalanine, and lysine. Moreover, MPI showed a median particle charge (-37.1 mV) compared to FPI, SPI, and LPI samples. MPI sample peak showed resistance to heat denaturation at a temperature greater than 200 °C when the DSC test was conducted. With respect to its rheological characteristics, it outperformed the other three protein isolates and exhibited the highest values of storage modulus G' and loss modulus G". Consequently, our study suggests that pulse-derived protein isolate mixture can be used as a unique type of nutritious dietary protein supplement. It could be a good nutritional alternative to proteins derived from animals.


Assuntos
Lupinus , Vicia faba , Animais , Humanos , Veganos , Glycine max , Dieta Vegana , Verduras , Proteínas de Plantas
14.
J Exerc Sci Fit ; 22(2): 140-144, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38404749

RESUMO

Purpose: The performance of sodium citrate has been investigated in high-intensity exercises, but fewer studies have addressed the role of citrate in weight-bearing exercises. Methods: Twenty fitness challenge athletes, aged 24-32 years, volunteered to participate in this crossover, placebo-controlled, double-blind study. Initially, ten athletes were given a placebo and asked to complete a fitness challenge (i.e., chin-ups, squat jumps, dips, walking lunges, sit-ups, and burpees-devil press). Another ten athletes were supplemented with sodium citrate 0.5 g/kg body mass supplements 3 h prior to performing the fitness challenges. The same procedures were completed two days later with the supplement and placebo dextrose groups switched in a cross-over design. Athletes and assessors were blinded for the experimental condition (placebo vs. verum). Lactate levels were measured 5 min after exercise. The athletes' performance on each item of the fitness challenge as well as their lactate levels, were compared. Differences between the means of the measured variables were contrasted using a dependent t-test. Results: Supplementing sodium citrate substantially improved athletes' performance in all six fitness challenge items (p < 0.05, 0.69

15.
J Intern Med ; 293(3): 384-397, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36208176

RESUMO

BACKGROUND: Meta-analyses of randomized controlled trials (RCTs) have demonstrated the efficacy of vitamin D supplementation for reduced cancer mortality, all-cause mortality, and respiratory tract infections. However, whether and to what extent this translates into effectiveness in real-world practice is unknown. METHODS: We assessed the association of vitamin D supplement use (as an over-the-counter drug or as part of a multivitamin product), vitamin D deficiency (25-hydroxyvitamin D, 25[OH]D <30 nmol/L), and insufficiency (25[OH]D 30 to <50 nmol/L) with all-cause and cause-specific mortality in 445,601 participants, aged 40-73 years, from the UK Biobank cohort. RESULTS: A total of 4.3% and a further 20.4% of the study participants reported regularly taking vitamin D or multivitamin supplements, respectively. Still, the majority had either vitamin D deficiency (21.0%) or insufficiency (34.3%). We detected 49 independent determinants of vitamin D deficiency and vitamin D supplement use and used them to adjust Cox regression models for all mortality outcomes. A total of 29,107 (6.5%) participants died during a median follow-up time of 11.8 years. Both vitamin D deficiency and insufficiency were strongly associated with all mortality outcomes. Self-reported vitamin D supplement use (83% over-the-counter/17% prescription drugs) and multivitamin intake were significantly associated with 10% and 5% lower all-cause mortality, respectively. Furthermore, regular vitamin D supplement users had 11%, 11%, and 29% lower cancer, cardiovascular disease, and respiratory disease mortality than nonusers, respectively (not significant for cardiovascular disease mortality). CONCLUSION: This large study suggests that in the real world, the efficacy of vitamin D supplements in reducing mortality may be at least as good as observed in RCTs.


Assuntos
Doenças Cardiovasculares , Neoplasias , Infecções Respiratórias , Deficiência de Vitamina D , Humanos , Doenças Cardiovasculares/prevenção & controle , Causas de Morte , Vitamina D , Vitaminas/uso terapêutico , Deficiência de Vitamina D/tratamento farmacológico , Suplementos Nutricionais
16.
J Nutr ; 152(12): 2789-2801, 2023 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35918260

RESUMO

BACKGROUND: Dietary supplement (DS) use is widespread in the United States and contributes large amounts of micronutrients to users. Most studies have relied on data from 1 assessment method to characterize the prevalence of DS use. Combining multiple methods enhances the ability to capture nutrient exposures from DSs and examine trends over time. OBJECTIVES: The objective of this study was to characterize DS use and examine trends in any DS as well as micronutrient-containing (MN) DS use in a nationally representative sample of the US population (≥1 y) from the 2007-2018 NHANES using a combined approach. METHODS: NHANES obtains an in-home inventory with a frequency-based dietary supplement and prescription medicine questionnaire (DSMQ), and two 24-h dietary recalls (24HRs). Trends in the prevalence of use and selected types of products used were estimated for the population and by sex, age, race/Hispanic origin, family income [poverty-to-income ratio (PIR)], and household food security (food-secure vs. food-insecure) using the DSMQ or ≥ 1 24HR. Linear trends were tested using orthogonal polynomials (significance set at P < 0.05). RESULTS: DS use increased from 50% in 2007 to 56% in 2018 (P = 0.001); use of MN products increased from 46% to 49% (P = 0.03), and single-nutrient DS (e.g., magnesium, vitamins B-12 and D) use also increased (all P < 0.001). In contrast, multivitamin-mineral use decreased (70% to 56%; P < 0.001). In adults (≥19 y), any (54% to 61%) and MN (49% to 54%) DS use increased, especially in men, non-Hispanic blacks and Hispanics, and low-income adults (PIR ≤130%). In children (1-18 y), any DS use remained stable (∼38%), as did MN use, except for food-insecure children, whose use increased from 24% to 31% over the decade (P = 0.03). CONCLUSIONS: The prevalence of any and MN DS use increased over time in the United States. This may be partially attributed to increased use of single-nutrient products. Population subgroups differed in their DS use.


Assuntos
Micronutrientes , Oligoelementos , Masculino , Humanos , Adulto , Criança , Estados Unidos , Inquéritos Nutricionais , Suplementos Nutricionais , Dieta , Vitaminas
17.
J Nutr ; 153(6): 1771-1782, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37044210

RESUMO

BACKGROUND: Although reported dietary supplement use is common in older adults, evaluations of dietary supplement use over the past 10 y are lacking. OBJECTIVE: This analysis determined changes in reported dietary supplement use in cognitively normal older adults (aged ≥ 55 y) using the National Alzheimer's Coordinating Center data from 2015 to 2019 using a serial cross-sectional study design. METHODS: The first available visit for cognitively normal participants aged ≥ 55 y from 2015 to 2019 with a complete medication form was used, resulting in 9357 participants. Associations between visit year categories and reported use of dietary supplement categories/individual supplements were tested using categorical statistics. To determine whether the probabilities of reported supplement use changed in 2019 compared with those of 2015, z-scores and two-sided P values were used. Weighted analyses were used to confirm analytical findings. RESULTS: When comparing 2015 and 2019, the reported use of any dietary supplement decreased from 77.7% in 2015 to 71.0% in 2019 (P < 0.0001); any vitamin from 72.5% to 65.5% (P < 0.0001); any mineral from 39.2% to 30.4% (P < 0.0001); "other" nonvitamin/nonmineral supplements from 34.4% to 26.9% (P < 0.0001), calcium from 31.2% to 21.7% (P < 0.0001), multivitamins from 48.4% to 38.4% (P < 0.0001), potassium from 5.6% to 3.5% (P = 0.001), vitamin C from 13.0% to 9.2% (P = 0.0002), chondroitin from 6.0% to 4.1% (P = 0.006), glucosamine from 11.1% to 6.5% (P < 0.0001), and all omega fatty acids from 25.2% to 17.0% (P < 0.0001). Reported use increased for vitamin B7/biotin from 3.1% in 2015 to 5.8% in 2019 (P = 0.0003), melatonin from 3.1% to 5.8% (P = 0.0002), and turmeric from 1.2% to 4.7% (P < 0.0001). CONCLUSION: Although the reported use of many major dietary supplement categories and individual supplements significantly decreased in older adults from 2015 to 2019, biotin, turmeric, and melatonin significantly increased. Because biotin may interfere with some laboratory tests, this may have important public health implications.


Assuntos
Doença de Alzheimer , Melatonina , Humanos , Idoso , Biotina , Estudos Transversais , Suplementos Nutricionais , Vitaminas
18.
J Nutr ; 153(1): 301-311, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36913466

RESUMO

BACKGROUND: Vitamins, minerals, and natural product (NP)-derived dietary supplements are commonly used among women with breast cancer, where interactions with treatments and the disease are possible, emphasizing the importance for health care providers to be aware of supplement use. OBJECTIVES: The study aimed to investigate current vitamin/mineral (VM) and NP supplement use among those diagnosed with breast cancer, including usage based on tumor type or concurrent breast cancer treatments and primary information sources for specific supplements. METHODS: Social media recruiting to complete an online questionnaire self-reporting current VM and NP use and breast cancer diagnosis and treatment information primarily attracted US participants. Analyses, including multivariate logistic regression, were performed on 1271 women who self-reported breast cancer diagnosis and completed the survey. RESULTS: Most participants reported current VM (89.5%) and NP (67.7%) use, with 46.5% (VM) and 26.7% (NP) using at least 3 products concurrently. Top-reported (>15% prevalence) products were vitamin D, calcium, multivitamin, and vitamin C for VM and probiotics, turmeric, fish oil/omega-3 fatty acids, melatonin, and cannabis for NP. Overall, VM or NP use was higher among those with hormone receptor-positive tumors. Although overall NP use did not differ according to current breast cancer treatments, VM use was significantly less common among those currently undergoing chemotherapy or radiation, but higher with current endocrine therapy. Among current chemotherapy users, specific VM and NP supplements with possible adverse effects were still used by 23% of respondents. Medical providers were the primary information source for VM, whereas NP information sources were more varied. CONCLUSIONS: Because women diagnosed with breast cancer commonly reported concurrent use of multiple VM and NP supplements, including those with known or underexplored risks (or benefits) in breast cancer, it is important for health care providers to inquire about and facilitate discussions regarding supplement use in this population.


Assuntos
Suplementos Nutricionais , Neoplasias , Suplementos Nutricionais/efeitos adversos , Vitaminas/uso terapêutico , Minerais , Inquéritos e Questionários , Modelos Logísticos
19.
Crit Rev Food Sci Nutr ; 63(21): 4855-4866, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34859731

RESUMO

Although creatine supplementation is well-known to increase exercise performance in acute high-intensity exercises, its role in aerobic performance based on VO2max is more controversial. Thus, we performed a systematic review and meta-analysis on the effects of creatine supplementation on VO2max. PubMed, Cochrane, Embase, and ScienceDirect were searched for randomized controlled trials (RCTs) reporting VO2max in creatine supplementation and placebo groups before and after supplementation. We computed a random-effects meta-analysis on VO2max at baseline, within groups following supplementation, on changes on VO2max between groups, and after supplementation between groups. Sensitivity analyses and meta-regression were conducted. We included 19 RCTs for a total of 424 individuals (mean age 30 years old, 82% men). VO2max did not differ at baseline between groups (creatine and placebo). Participants in both groups were engaged in exercise interventions in most studies (80%). Using changes in VO2max, VO2max increased in both groups but increased less after creatine supplementation than placebo (effect size [ES] = -0.32, 95%CI = -0.51 to -0.12, p = 0.002). Comparisons after creatine supplementation confirmed a lower VO2max in the creatine group compared to the placebo group (ES= -0.20, 95%CI = -0.39 to -0.001, p = 0.049). Meta-analysis after exclusion from meta-funnel resulted in similar outcomes in a subgroup of young and healthy participants. Meta-regressions on characteristics of supplementation, physical training, or sociodemographic were not statistically significant. Creatine supplementation has a negative effect on VO2max, regardless of the characteristics of training, supplementation, or population characteristics.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2021.2008864 .


Assuntos
Creatina , Exercício Físico , Masculino , Humanos , Adulto , Feminino , Suplementos Nutricionais
20.
Crit Rev Food Sci Nutr ; 63(31): 10659-10677, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38054787

RESUMO

In recent years, plant-based diets have experienced increasing popularity. However, plant-based diets may not always ensure an adequate supply of micronutrients, in particular calcium. We performed a systematic review and meta-analysis of calcium intake in vegan and vegetarian diets as compared to omnivorous diets. We searched PubMed and Web of Science and identified 2,009 potentially relevant articles. Mean calcium intake values were pooled and standardized mean differences (SMD) and 95% confidence intervals (CI) were computed.We analyzed 74 studies, including 7,356 vegan, 51,940 vegetarian, and 107,581 omnivorous participants. Of these, dietary calcium intake was examined in 23 studies of vegans, 60 studies of vegetarians and 74 studies of omnivores. Vegans showed a substantially lower calcium intake than vegetarians (SMD = -0.57; 95%CI = -0.83 to -0.32; p = <0.0001) and omnivores (SMD = -0.70; 95%CI = -0.95 to -0.59; p < 0.0001), whereas no statistically significant difference in calcium intake was noted between vegetarians and omnivores (SMD = 0.07; 95%CI = -0.04 to 0.19; p = 0.1976). In conclusion, vegans show a lower calcium intake than vegetarians and omnivores. This finding emphasizes the need for vegans to monitor their calcium status.


Assuntos
Cálcio , Veganos , Humanos , Dieta Vegetariana , Dieta , Dieta Vegana
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