Use Of Dietary Supplements Research Articles

Dietary Intake and Supplement Use in Competitive Women Bodybuilders.

(1) Background: Women bodybuilders use extreme diets, dietary supplementation, and training regimes to sculpt their physiques. Women's participation in bodybuilding competitions has increased since the 1980s. Currently, studies on their dietary intake and supplement use are limited. Their dietary intake may be of poor quality and low in several micronutrients, while supplement use appears to be omnipresent. Thus, the aim of this study was to examine and compare the dietary intake, supplement use, and diet quality of in-season and off-season women bodybuilders. (2) Methods: In a cross-sectional design, we compared dietary intake, supplement use, and diet quality between seasons in women bodybuilders (n = 227). An online questionnaire was developed, validated, and administered to assess all non-dietary and supplement variables. The Automated Self-Administered 24 h Dietary Assessment Tool was used to collect four 24 h dietary recalls. The Healthy Eating Index-2015 (HEI-2015) was used to calculate diet quality. The analysis of covariance and Welch's t-tests were used to assess the differences between in-season and off-season women bodybuilders' dietary intake, supplement, and HEI-2015 variables. (3) Results: In-season competitors reported consuming significantly less energy, carbohydrates, and fat but more protein than off-season competitors. All competitors consumed excess protein, while in-season competitors consumed excess fat and off-season competitors consumed less energy than the physique athlete nutrition recommendations. All competitors' micronutrient intakes were above the Dietary Reference Intakes. Supplements were used by all competitors, and the mean number used was similar between seasons. The HEI-2015 scores were not significantly different between seasons yet were below the US Dietary Guidelines for Americans. (4) Conclusion: Women bodybuilders would benefit from health education to achieve physique athlete nutrition recommendations, improve diet quality, and safe/efficacious supplement use to reach physique goals and improve overall health.

A national anti-doping education programme reduces doping susceptibility in British athletes

The World Anti-Doping Agency’s International Standard for Education instructs that national and international sport organisations evaluate their education programmes. We addressed this directive by examining the effectiveness of a national anti-doping programme. Athletes (N = 302, 41% female) completed measures of doping susceptibility, intention to use dietary supplements, Spirit of Sport and moral values, anti-doping knowledge and practice, and whistleblowing, prior-to and three-months after attending an anti-doping education programme. At three-month follow-up, athletes reported decreased doping susceptibility and intention to use dietary supplements coupled with increased importance of values, anti-doping knowledge, anti-doping practice and whistleblowing. Within-participant, moderated-mediation analyses revealed that programme-related changes in doping susceptibility were indirectly related to changes in intention to use dietary supplements, and, that this indirect relationship was moderated by moral values. These findings confirm the effectiveness of a national anti-doping education programme and highlight the contribution of dietary supplement use and personal values to changes in doping susceptibility.

Prevalence and Reasons for Use of Dietary Supplements and Energy Drinks Among Air Force Personnel

Prevalence and Reasons for Use of Dietary Supplements and Energy Drinks Among Air Force Personnel

Motivational Drivers behind the Consumption of Dietary Supplements by Leisure-Time Athletes.

The prevalence of dietary supplement use has been growing continuously worldwide. Nevertheless, limited research evidence is available on dietary supplement usage related to the segment of leisure-time athletes with the determinants of motivational drivers, sport types, and demographic characteristics. This research, which was conducted in Hungary among leisure-time athletes, aims to learn about the demographic and sports characteristics of consumers who identified themselves as active dietary supplement consumers in the survey. The motivational drivers for consuming dietary supplements and their differences, as well as the frequency of dietary supplement consumption in each sports category, are examined. The findings of the study provide valuable insights into the key motivational drivers, among which health preservation, improvement in physical well-being, and cartilage protection are predominant. The results show that there are significant differences between segments taking part in different leisure-time sport activities and age groups when it comes to dietary supplement usage. Three different segments were identified based on the motivational drivers examined. As a limitation, to note is that due to the sample size, the study can be considered as prospective. In practical terms, the results of the study can be used to support marketing projects that aim to reach leisure-time sport athletes.

Perspectives and practices of nutritionists on dietary supplements for elite soccer teams: a cross-sectional survey study.

Dietary supplements are part of the nutritional strategies frequently applied in sports performance support. With growing research on this subject and high demand from athletes, nutritionists need to keep up to date with the latest evidence and utility of dietary supplements, particularly in real-world contexts. As information about the use of dietary supplements among elite soccer players is still scarce, this work aimed to know how nutritionists working with elite soccer teams perceive and use these substances in their daily practice. A questionnaire previously used to describe nutritionists' beliefs and attitudes regarding the use of dietary supplements in a clinical context was adapted for this study. The online questionnaire was addressed to nutritionists working with elite soccer teams from six European Leagues and Brazil, between November 2022 and February 2023. Overall, the participants considered themselves well-trained (76.9%), knowledgeable (95.4%), and interested in dietary supplements (95.4%). The majority (70.8%) of the participants agreed or strongly agreed to recommend dietary supplements to soccer players. Personal usage of dietary supplements was associated with recommending supplements (p < 0.001), but no relationships were found with years of experience and academic level. Nutritionists working with elite soccer players consider the use of dietary supplements for performance-enhancement purposes and not only to compensate for nutritional deficits, which might contribute to their higher interest, training and perceived knowledge about this topic. Participants recognize players' interest in dietary supplements, and are mindful of the safety and efficacy of these products. The present study suggests that nutritionists working with elite soccer teams are among the highest prescribers of dietary supplements, although personal usage is lower than that of nutritionists working in a clinical context.

Association between dietary supplement use and mortality among US adults with diabetes: a longitudinal cohort study

BackgroundDespite the popularity of dietary supplements, their effectiveness and safety in patients with diabetes remain controversial. Furthermore, evidence from clinical trials may not be generalizable to real-world settings. This study examined the association between dietary supplement use and mortality outcomes among patients with diabetes based on a nationally representative sample of US adults.MethodsThis study analyzed data from National Health and Nutrition Examination Survey (NHANES) 1999–2018. Supplement users referred to adults with diabetes who reported the use of any dietary supplements in the last 30 days, and with a cumulative duration of ≥ 90 days. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between supplement use and all-cause mortality, and mortality from cardiovascular diseases (CVD), diabetes, and cancer. Subgroup analysis of different supplement classes (vitamins, minerals, botanicals, amino acids, fatty acids, probiotics and glucosamine) were also conducted.ResultsWe included 8,122 adults with diabetes (mean age: 59.4 years; 48.7% female), of whom 3,997 (54.0%) reported using supplements regularly. Vitamins (87.3%), minerals (75.3%) and botanicals (51.8%) were the most popular supplements. At a median follow-up of 6.9 years, 2447 all-cause deaths had occurred. Overall supplement use was not associated with risk of all-cause mortality among patients with diabetes (HR = 0.97, 95% CI: 0.87 to 1.08, P = 0.56). Subgroup analyses suggested that amino acid use was associated with a lower all-cause mortality (HR = 0.66, 95% CI: 0.46 to 0.96, P = 0.028), while the use of fatty acids (HR = 0.62, 95% CI: 0.42 to 0.92, P = 0.018) and glucosamine (HR = 0.69, 95% CI: 0.51 to 0.95, P = 0.022) supplements were significantly associated with lower CVD mortality.ConclusionsOur results derived from real-world data suggested that overall supplement use was not associated with any mortality benefit in patients with diabetes. However, there is preliminary evidence that suggests a protective effect of amino acid use on all-cause mortality, and a benefit of fatty acids and glucosamine supplement use on CVD mortality. Future large-scale longitudinal studies are needed to investigate the association between dietary supplement use and other intermediate diabetes-related outcomes, such as glucose control and reducing diabetes-related complications.

Nootropic supplements for esports.

Background: esports, or organized video game competitions, have been expanding quickly. The use of dietary supplements by esports players appears vulgarized but lacks supporting evidence. Objectives: To outline studies that tested the effects of dietary supplements on video gaming, summarize their findings, highlight knowledge gaps, and recommend future research. Eligibility criteria: Clinical trials published in English between 1990 and 2023 that assessed the effects of dietary supplements on the cognitive performance of video gamers. Sources of evidence: The Web of Science, PubMed, Scopus, and Google Scholar databases. Charting methods: PRISMA's (2020) flow diagram was used to create the data chart. Results: Sixteen studies were outlined. Thirteen were randomized, thirteen applied acute interventions, ten applied a crossover design and only three weren't placebo-controlled. Of the 10 studies that included caffeine (40-200 mg), four reported significant positive effects on cognition (attention, processing speed, working memory), two on first-person shooter video gaming performance (reaction time, hit accuracy, time to hit 60 targets), and one on Tetris game score. All 3 studies that included arginine silicate (1500 mg) reported significant improvements in one or more aspects of cognition (reaction time, attention, visual representation, and spatial planning). Two studies that tested sucrose (21 and 26.8 g) didn't report significant improvements, while one study that tested 26.1 g of glucose registered significant positive effects on processing speed and sustained attention. Conclusions: The published literature has focused on the effects of caffeine, which may exert both positive and negative effects on esports players. Additional, high-quality research is needed.

Development and Validation of Gas Chromatography–Mass Spectrometry Method for Quantification of Sibutramine in Dietary Supplements

The use of dietary supplements (DSs) has dramatically increased in recent decades. However, around 20% of these products are reported to contain pharmacologically active undeclared compounds, most of which could expose consumers to serious side effects. According to recent data, some of the most commonly detected undeclared compounds are also considered doping and are prohibited by the World Anti-Doping Agency (WADA). One of the most frequently detected undeclared substances in DSs used for promoting weight loss is sibutramine. In 2011, all medicines containing sibutramine were urgently withdrawn from Europe and US markets because of serious side effects. In the present study, in order to detect and quantify sibutramine in DSs, a rapid, sensitive, and reliable gas chromatography with mass spectrometry (GC-MS) method was developed. The method was validated according to the ICH guidelines and demonstrated good linearity, accuracy, precision, and robustness. The limits of detection and quantification were 0.181 μg/mL and 0.5488 μg/mL, respectively. The method was applied to analyze 50 DSs promoting weight loss, fat burning, and performance enhancement. Sibutramine was detected in six of them in a range of 16.59–14,854.94 μg/per capsule. The high concentrations of sibutramine detected in some samples raise concerns about the potential health risks associated with the use of adulterated DSs. The proposed GC-MS method could be used successfully in the quality control of DSs or in different research programs, contributing to safety and the prevention of associated side effects.

NAFLD and nutraceuticals: a review of completed phase III and IV clinical trials.

Nonalcoholic Fatty Liver Disease (NAFLD) has become a significant public health concern, affecting approximately one-fourth of the population. Despite its prevalence, no FDA-approved drug treatments specifically target NAFLD. To provide a review of clinical trials investigating the use of herbal remedies and dietary supplements in NAFLD management, utilizing the ClinicalTrials.gov database. This review evaluates the current evidence by examining completed phase III and IV clinical trials registered on ClinicalTrials.gov. An exhaustive search was performed on April 17, 2023, using the terms "Nonalcoholic Fatty Liver Disease" and "NAFLD." Two independent reviewers appraised eligible trials based on pre-defined inclusion and exclusion criteria. An initial search yielded 1,226 clinical trials, with 12 meeting the inclusion criteria after filtration. The majority of trials focused on Omega-3 fatty acids (20.0%) and vitamin D (26.7%), followed by caffeine, chlorogenic acid, ginger, phosphatidylcholine, Trigonella Foenum-graecum seed extract, vitamin C, and vitamin E (each 6.7%). Most studies were Phase 3 (75.0%) and used a parallel assignment model (91.7%). Quadruple masking was the most prevalent technique (58.3%), and Iran was the leading country in terms of trial locations (25.0%). These interventions constitute two herbal interventions and nine supplement interventions. This reveals a diverse range of nutraceuticals, with Omega-3 fatty acids and vitamin D being predominant in the management of NAFLD. The global distribution of trials highlights the widespread interest in these therapeutics. However, more rigorous, large-scale trials are needed to establish safety, efficacy, and optimal dosages.

Association between Nonfood Pre- or Probiotic Use and Cognitive Function: Results from NHANES 2011-2014.

In this study, we collected data from the National Health and Nutrition Examination Survey (NHANES) for the years 2011-2014. Multiple linear regression and logistic regression were used to analyse the association between nonfood pro- or prebiotic use and cognitive function among elderly Americans. To estimate the potential unobserved results, propensity score matching (PSM) was used to analyse the causal effect. Nonfood pro- or prebiotic use was analysed through the Dietary Supplement Use 30-Day Study. Cognitive function was evaluated by the Digit Symbol Substitution Test (DSST), the Animal Fluency Test (AFT), the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), and a composite Z-score calculated by summing the Z-scores of three tests. Male participants who used nonfood pro- or prebiotics tended to have higher comprehensive cognitive function (sum.z) with a β-coefficient of 0.64 (95% CI: 0.08-1.19). Probiotics or prebiotics may be a protective factor against cognitive impairment in males, with an odds ratio of 0.08 (95% CI: 0.02-0.29). Furthermore, the average treatment effect for the treated (ATT) with nonfood pro- or prebiotics (0.555) on sum.z in males was statistically significant (p < 0.05). Our research revealed that nonfood pre- or probiotic use was an effective method to improve cognitive function in elderly men from the USA.

Relevance of Dietary Supplement Use in Gastrointestinal-Cancer-Associated Cachexia.

Cancer cachexia is a multi-organ syndrome with unintentional weight loss, sarcopenia, and systemic inflammation. Gastrointestinal (GI) cancer patients are more susceptible to cachexia development due to impaired nutrient absorption and digestion. Given the widespread availability and relatively low cost of dietary supplements, we examined the evidence and effects of fish oil (omega-3 fatty acids), melatonin, probiotics, and green tea for managing symptoms of GI cancer cachexia. A literature review of four specific supplements was conducted using PubMed, Google Scholar, and CINAHL without a date restriction. Of 4621 available literature references, 26 articles were eligible for review. Fish oil decreased C-reactive protein and maintained CD4+ cell count, while melatonin indicated inconsistent findings on managing cachexia, but was well-tolerated. Probiotics decreased serum pro-inflammatory biomarkers and increased the tolerability of chemotherapy by reducing side effects. Green tea preparations and extracts showed a decreased risk of developing various cancers and did not impact tumor growth, survival, or adverse effects. Among these four supplements, probiotics are most promising for further research in preventing systemic inflammation and maintaining adequate absorption of nutrients to prevent the progression of cancer cachexia. Supplements may benefit treatment outcomes in cancer cachexia without side effects while supporting nutritional and therapeutic needs.

The Relationship between Knowledge, Dietary Supplementation, and Sleep Quality in Young Adults after the COVID-19 Pandemic.

Sleep is one of the most important factors affecting the quality of life. More than 50% of Polish adults have sleeping disorders, and young adults are the ones particularly vulnerable to this. This is why the analysis of the predictors of sleep quality, such as sleep hygiene knowledge and dietary knowledge, in young adults is a very important topic, especially after the COVID-19 pandemic, which may have affected sleeping habits. 402 young adults (mean age 28.12 ± 6.08 years old) were enrolled in the study during the COVID-19 pandemic. Sleep quality was assessed with the Pittsburgh Sleep Quality Questionnaire, while dietary knowledge and sleep hygiene knowledge were assessed with dedicated questionnaires. The participants were also asked about the use of specific dietary supplements. The analysis showed that sleep hygiene knowledge was significantly associated with sleep length (R = -0.17, p = 0.003) and overall sleep quality (R = -0.17, p = 0.005), while dietary knowledge significantly correlated with time to fall asleep (R = -0.12, p = 0.026). The regression analysis revealed that sleep hygiene knowledge was a significant negative predictor of sleep quality impairment (β = -0.13, p = 0.028). Significant results were also obtained for the use of supplements (β = -0.20; p = 0.001) and the use of medications (β = -0.32, p = 0.001), which were negative predictors of sleep quality impairment. This study showed that increased sleep hygiene knowledge promoted improved sleep length and overall sleep quality. In addition, dietary knowledge significantly correlated with time to fall asleep. On the other hand, decreased sleep quality was observed in participants who used medications or dietary supplements.

An Exploratory Study Investigating the Prevalence of Gastrointestinal Symptoms in Collegiate Division I American Football Athletes.

Gastrointestinal (GI) symptoms may limit performance, but their prevalence and impact among team sports athletes is not well-documented. The objective of this study was to examine the prevalence of GI symptoms in a small sample of collegiate DI American football athletes, using a survey including the Gastrointestinal Symptoms Ratings Scale (GSRS). Forty-six athletes responded to the survey and reported scores for the 15-question GSRS with additional questions about dietary habits and supplement use. A total of 44 athletes were included in the study (45% of the current roster, age: 20.7 ± 1.7 years, 50% Afro-American or black, 39% skill position, 18% NSAIDs use, and 41% reporting protein supplement use); approximately half of the athletes (52%) reported experiencing GI complaints during exercise. Two-thirds of the athletes (61%) reported at least one or more GI symptoms in general, and 50% reported at least four moderate complaints. Seven athletes (16%) reported ≥2 severe GI symptoms with 5-13 moderate complaints. The most reported symptom was stomach pain (39%, n = 17), followed by hunger pain (36%, n = 16). Athletes reporting the use of protein supplements reported a higher GSRS score (22.0 and interquartile range (IQR) 17.0-31.8) vs. athletes not reporting protein use (15.0 and IQR 15.0-19.3), p = 0.001. Most athletes surveyed reported experiencing GI symptoms. A small group of these athletes reported multiple, varied, and severe symptoms that were associated with self-reported protein supplement use. In conclusion, the number of complaints varied among athletes, confirming the value of integrating the GSRS for screening purposes, and the expected need for individual dietary treatment approaches.

A Global Overview of Dietary Supplements: Regulation, Market Trends, Usage during the COVID-19 Pandemic, and Health Effects.

Over the last 20 years, the use of dietary supplements (DS) has continued to grow in many countries. Due to the public health crisis brought on by the COVID-19 pandemic and amidst fears regarding COVID-19 vaccines and their low supply in many regions of the world, there has been a marked interest in the use of DS as alternative means of protecting against and treating this emerging disease, as well as boosting the immune system and minimizing the risk of inflammation. Despite a lack of evidence to suggest their efficacy, a surge in the sales of DS has been reported in many parts of the world. Questions have also been raised about the health effects associated with DS due to their increased use during the health crisis. Numerous scientific studies have demonstrated their beneficial properties as well as some adverse and even toxic effects. In addition, given the current global interest in this issue, a review is needed to establish the status of dietary supplements before and during the health crisis. The aim of this review is to summarize the current evidence on the impact of dietary supplements on the incidence of the COVID-19 pandemic, as well as their regulation and associated market trends. First, we provide an overview of DS, including a comprehensive review of the legislative and regulatory aspects of DS in the USA, China, the EU, and Algeria. Second, we describe the prevalence of the most commonly consumed DS and their efficacy as a prophylactic modality in the era of COVID-19. Additionally, we examine the structure and size of the DS market in the countries that predominantly produce and import them, its global market trend, and the impact of the COVID-19 pandemic on market growth. Finally, in this review, we also discuss the profile of DS users.

Leveraging blockchain to improve nutraceutical supply chain resilience under post-pandemic disruptions

Due to the pandemic, there has been an increase in the use of dietary supplements to boost the body's immune system. A demand–supply mismatch exists as a result of the unexpected increase in demand. The nutraceutical industry has been working on mechanisms to improve manufacturing efficiency and address bottlenecks in sourcing and production. The current study is attempting to address the issue of identifying these bottleneck problems by proposing a mathematical model to devise the optimal costs associated with the operations, as well as attempting to see the possibility of blockchain technology adoption as a better alternative to addressing these bottlenecks. The study compares adding an assembly line to existing infrastructure to implementing blockchain technology to improve manufacturing process efficiency. The study increases the likelihood of blockchain technology being used in the nutraceutical industry and calls for more research at the intersection of blockchain, nutraceuticals, and optimization.

Recommendations for Nutritional Supplementation in Pediatric Oncology: A Compilation of the Facts.

As one of the few modifiable risk factors, the importance of dietary patterns for both disease prevention and treatment outcome in pediatric oncology has gained increasing popularity. Malnutrition is associated with lower survival rates, tolerance to treatment, and quality of life. Yet, especially in children with malignancies, nutritional deterioration is common, and pediatric cancer patients often present with inadequate intake of micro- and macronutrients alike. Despite the reported widespread use of dietary supplements, few empirical data provide a basis for clinical recommendations, and evidence for their efficacy is inconsistent. Current literature lacks a systematic approach as to how and which supplements should be recommended for specific patients, types of cancer, or during specific treatments. The aim of this review is to highlight the role of the most frequently used nutrients in pediatric malignant diseases and to give a practical guide based on current scientific evidence. A comprehensive literature search was conducted on PubMed through April 2023 to select meta-analyses, systematic reviews, observational studies, and individual randomized controlled trials (RCTs) of macro- and micronutrient supplementation in pediatric oncology. The search strategy included the following medical subject headings (MeSH) and keywords: "childhood cancer", "pediatric oncology", "nutritional status", "dietary supplements", "vitamins", "micronutrients", "calcium", "magnesium", "vitamin D", "zinc" "glutamine", "selen", and "omega-3 fatty acids". The reference lists of all relevant articles were screened to include potentially pertinent studies. The present review provides a comprehensive and updated overview of the latest evidence about the role of nutrition and diet in pediatric oncology, also focusing on different nutritional interventions available for the management of the disease. We summarize evidence about the importance of adequate nutrition in childhood cancer and the role of several micronutrients and critically interpret the findings. Possible effects and benefits of supplementation during chemotherapy are discussed, as are strategies for primary and secondary prevention. We here describe the obvious benefits of dietary supplementation for childhood cancer. Further large-scale clinical trials are required to verify the impacts of deficiencies and the possible benefits of supplementation and optimal dosages. (337 words).

Prevalence of dietary supplement use and associated factors among fitness center users in Madrid, Spain

Consumption of supplements is common among fitness center users worldwide, including in Spain. The aim of this study was to evaluate the association between dietary supplement use and associated factors (demographic and sports practice) among fitness center users from Madrid, Spain. A cross-sectional study was carried out with users of fitness centers in Madrid, Spain. An online questionnaire was used, containing questions about demographic data, physical exercise, and consumption of dietary supplements. Data were analyzed using Student's t-test for continuous variables and Fisher's exact or χ-square test for categorical variables. The significance level used was p&lt;0.05. Of the 179 individuals evaluated, 39.7% consumed supplements, which was more reported by younger individuals (p=0.024), by men (p&lt;0.001), and by self-prescribed (45.1%). The consumption of supplements was associated with longer weekly training time (382.39± 203.0; p&lt;0.001), higher weekly frequency (&gt;5 times; p=0.038), and the practice of combined exercise (51.4%; p&lt;0.001). Most men used more than 3 supplements (p&lt;0.001) for more than one year (52.1%; p&lt;0.001). Both genders also reported gaining muscle mass (24.6%) as the main motivation for using supplements. In conclusion, supplement consumption was higher among men, younger individuals, and self-prescribed. Consumption was also related to the reason for gaining muscle mass, the practice of anaerobic+aerobic exercises, and greater weekly training time and frequency.

A QUALITATIVE ASSESSMENT OF THE LABELING INFORMATION OF COLLAGEN-CONTAINING FOOD SUPPLEMENTS

The use of collagen dietary supplements (CDS) has increased dramatically, creating a large market for these products. With so many options available, it is important for consumers and medical professionals to be well-informed about the composition of these supplements. The aim of this study was to compare the information provided on the labels of CDS with science-based literature. The study conducted an electronic search of randomized, double-blind, control, and pilot studies, which all evaluated the use of oral native or hydrolyzed CDS. All studies were searched in PubMed, and had to be published in English between 2009-2022, August in PubMed. After the initial search, 33 were used for analysis. These studies were then compared to 147 CDS labels registered with the Food Veterinary Service (FVS) in Latvia. The results showed that while studies confirm the benefits of CDS for health, the labels registered in FVS often lack important information about the collagen source, dosage, and duration of use. This results in a significant frequency of errors and potential misuse compared to current scientific knowledge. This makes it challenging for consumers and medical professionals to make informed decisions when purchasing and using collagen supplements.

Are dietary supplement users more likely to dope than non-users?: A systematic review and meta-analysis.

In the past decade, a body of evidence has reported that dietary supplement use is related to prohibited performance enhancing substance use (i.e., doping). To help international and national sport organisations understand the degree to which dietary supplement use is related to doping, the objectives of this systematic review and meta-analysis were to 1) compare the prevalence of doping between dietary supplement users and non-users and 2) identify whether supplement use is related to doping social cognitive factors. We searched for studies sampling athletes and that measured both dietary supplement use and doping in EMBASE, MEDLINE, PsychINFO, CINAHL and SPORTDiscus from database creation to May 2022. Risk of bias was assessed using JBI Critical Appraisal Checklist for cross-sectional studies and the STROBE checklist. Twenty-six cross-sectional studies, involving 13,296 athletes were included. Random-effect models revealed that doping was 2.74 (95% CI=2.10 to 3.57) times more prevalent in dietary supplement users (pooled prevalence = 14.7%) than non-users (6.7%), and that users reported stronger doping intentions (r=0.26, 0.18 to 0.34) and attitudes (r=0.21, 0.13 to 0.28) compared to non-users. Preliminary evidence also suggests that dietary supplement users were less likely to dope if they were more task oriented and had a stronger sense of morality. Results of the review are limited by the cross-sectional design used in all studies and lack of consistency in measurement of dietary supplement use and doping. Data indicate that athletes using dietary supplements are more likely to self-report doping Anti-doping policy should, therefore, target dietary supplement use in anti-doping education programmes by providing alternative strategies for performance enhancement or highlighting the safest ways they can be consumed. Similarly, as a large proportion of athletes use dietary supplements without doping, further research is needed to understand the factors that protect a dietary supplement user from doping. No funding was received for the review. A study protocol can be found here: https://osf.io/xvcaq.

Exploring the perception of dietary supplement intake amongst gym users in Klang Valley, Malaysia

Background: Gym users are one of the populations who frequently consume dietary supplements. Nevertheless, data investigating the perspective of gym users regarding dietary supplement intake are still lacking. Our qualitative study aims to acquire insights into the perceptions of gym users regarding dietary supplement consumption. Methods: A total of 10 gym users who have a membership and are actively training at the gymnasium were recruited from Selangor and Kuala Lumpur, Malaysia. In-depth interview was conducted, and all responses were recorded and transcribed verbatim. The data were analysed using the NVivo version 12 software. Results: All participants consume dietary supplements almost every day, with most of them taking at least three supplements a day. Five themes emerged from these interviews: (1) gym and the use of dietary supplements, (2) reasons for supplement intake, (3) source of information, (4) supplement perceptions and beliefs and (5) health screening experience. Half of the participants did not consult with any nutritionist or dietitian before taking dietary supplements. The reasons for consuming supplements are to improve muscle mass, enhance performance, maintain overall health, fasten recovery time and prepare for competition. Our findings suggest that participants perceived supplements to be beneficial and exceeded the potential adverse effects. Conclusions: Lack of awareness amongst the recruited gym users in Klang Valley, Malaysia, regarding the potential risk of side effects suggests that there is a need to provide correct information about the benefits and risks of using dietary supplements.