Analysis and Screening of Commercialized Protein Supplements for Sports Practice

"It's not like they're selling drugs over the counter" A qualitative exploration of risks, regulations and packaging attribute perceptions of sports foods in non-athletes

Sports foods are increasingly being consumed by non-athletes in Australia, despite their intended purpose to supplement additional nutrient intake for athletes. Evidence suggests that these are perceived as regular foods and are being used by non-athletes for purposes contrary to which they were designed, posing health risks. Consumers are also relying on digital media sources for the recommendation of products and using misleading packaging information to select products, although their reasons are unclear. This study aimed to explore non-athlete consumers' perceptions of the risks, regulations and suggestions for improvement and, how warnings and packaging attributes guide non-athlete sports food choices in Australia. Qualitative semi-structured interviews with 15 non-athlete Australian adult sports food consumers were conducted. Reflexive thematic analysis was used to code responses using NVivo software. Participants had conflicting views on the risks associated with sports food consumption perceiving them to be high risk to others but of limited risk to themselves. Consumers trusted the Nutrition Information Panel and claims more than other attributes, and these were seen as more credible. Digital media was the key source of recommendation for sports food selection. Participants mentioned that warnings were generic, believed they were not applicable to them and that government regulations lacked credibility. Participants also suggested improvements for warning labels and regulatory measures. Consumption of sports foods by non-athletes is influenced by attitudes towards personal risks, the persuasive influence of digital media, and perceptions of the warnings and regulations as inadequate. Findings highlight the need for stricter packaging and regulations that ensure marketing controls and provide safer sports food products to mitigate some of the risks that non-athletes face when selecting these products.

Effects of Quercetin and Citrulline on Nitric Oxide Metabolites and Antioxidant Biomarkers in Trained Cyclists

BACKGROUND

Quercetin (QCT) and citrulline (CIT) have been independently associated with improved antioxidant capacity and nitric oxide (NO) production, potentially enhancing cardiovascular function and exercise performance. This study aimed to evaluate the combined and independent effects of QCT and CIT supplementation on NO metabolites and antioxidant biomarkers in 50 trained cyclists undergoing a 20 km cycling time trial (TT).

METHODS

In a randomized, double-blind, placebo-controlled design, forty-two male and eight female trained cyclists were assigned to QCT + CIT, QCT, CIT, or placebo (PL) groups. Supplements were consumed twice daily for 28 days. Biochemical assessments included NO metabolites (nitrate/nitrite), ferric reducing antioxidant power (FRAP), superoxide dismutase (SOD) activity, and antioxidant capacity, measured pre- and post-TT.

RESULTS

NO metabolites were significantly elevated post-supplementation (p = 0.03); however, no significant interaction effects were observed for NO metabolites, FRAP, SOD, or antioxidant capacity across the groups (p > 0.05). Post-hoc analyses revealed that QCT significantly reduced FRAP concentrations compared to PL (p = 0.01), while no significant changes in SOD or antioxidant capacity were found across any groups.

CONCLUSIONS

These findings suggest that combined and independent QCT and CIT supplementation did not significantly improve these biomarkers, suggesting that baseline training adaptations, supplementation timing, and individual variability may influence the efficacy of these compounds in enhancing exercise performance and oxidative stress markers. The ergogenic efficacy of QCT + CIT on antioxidant-related markers remains inconclusive.

Analysis of food supplements and sports foods consumption patterns among a sample of gym-goers in Portugal

BACKGROUND

Gym-goers usually seek methods to improve performance, muscle gain, and overall health. One of the main strategies is including food supplements (FS) into their routine as aids to enhance their athletic capabilities and satisfy their nutritional needs. Thus, this study aimed to investigate and characterize the main FS and Sports Foods (SF) currently consumed, as well as the main reasons for their use and the source of advice in a group of gym-goers in the Lisbon Metropolitan Area (Portugal).

METHODS

A cross-sectional study was conducted, including 303 gym-goers from Lisbon, Portugal, who were 133 women and 170 males (30.8 ± 12.9 years old). Face-to-face interviews were used by qualified researchers to gather data.

RESULTS

Most of the interviewed athletes (71.95 %) took FS/SF, being men the main consumers. On average, 1.59 supplements were consumed per athlete. Logistic regression models indicated significant associations between age, gender, and motivations for gym attendance. While men and younger groups attended mainly for hypertrophy, women and older groups were focused on well-being. Protein (59.17 %) was the most used FS/SF, followed by creatine (41.28 %) and multivitamins (27.06 %). Men and younger individuals preferred protein and creatine, while older individuals focused more on specific vitamins and minerals. Women seemed to prefer L-carnitine and protein yogurts. Main sources of information included the internet, friends, and dietitians with notable gender and age-based preferences. Online stores were the main place of purchase. Monthly expenditures on FS/SF were not significantly affected by age or gender, but motivations for use had an influence.

CONCLUSION

Most of the athletes interviewed took FS/SF, being men the major consumers. Protein was the principal FS/SF used, with online stores being the main place of purchase and the internet the primary source of information. Age and gender were key factors in adopted training, in the FS/SF chosen, and in the source of information selected. It is crucial that health professionals take primary responsibility for providing this guidance.

Appraisal of potentially toxic metals contamination in protein supplements for muscle growth: A chemometric approach and associated human health risks

BACKGROUND

The use of protein supplements by athletes has risen due to their effectiveness in meeting dietary needs. However, there is a growing concern about the presence of potentially toxic metals (PTMs. Al, Cr, Mn, Ni, Cu, Zn, Cd, and Pb) in these supplements. Consequently, it is crucial to evaluate the levels of these PTMs to ensure the safety of the supplements.

METHODS

The objective of the current study was to assess the PTMs concentrations in protein supplements and examine any possible health hazards. Twenty-five samples of protein supplements were purchased from different pharmacies to screen them for metals. Inductively coupled plasma-optical emission spectrometry (ICP-OES) was utilized to analyze metal content. Additionally, chemometric methods such as Pearson's correlation coefficient (PCC), principal component analysis (PCA), and hierarchical cluster analysis (HCA) were employed to identify possible sources of PTMs contamination in protein supplements.

RESULTS

Concentration ranges for PTMs were found as, Al (0.03-3.05 mg/kg), Cr (0.11-0.89 mg/kg), Mn (1.13-8.40 mg/kg), Ni (0.06-0.71 mg/kg), Cu (1.05-5.51 mg/kg), Zn (2.14-27.10 mg/kg), Cd (0.01-0.78 mg/kg), and Pb (0.06-0.57 mg/kg). The weekly intake of Cd exceeded the level of tolerable weekly intake (TWI) set by the European Food Safety Authority (EFSA).

CONCLUSION

Athletes, bodybuilders, fitness enthusiasts, dieters, young adults and adolescents, and health-conscious individuals should be conscious of Cd concentration as it does not compliance the TWI set by EFSA. Target hazard quotient (THQ < 1), hazard index (HI < 1), margin of exposure (MOE ≥ 1), percentile permitted daily exposure (% PDE < 100), and cumulative cancer risk (CCR < 1 × 10-3) analyses revealed that there are no appreciable non-carcinogenic and carcinogenic health risks associated with the use of these products.

A Cross-Sectional Study of Sports Food Consumption Patterns, Experiences, and Perceptions amongst Non-Athletes in Australia

Sports foods are designed for athletes, yet their availability, type, and sales have increased over the past decade, likely driven by non-athlete use. This could lead to detrimental health outcomes via over/misuse or unwanted side effects. The aim of this study was to describe sports food consumption patterns and associated drivers, consumption reasons, perception of risks, and side effects experienced amongst non-athletes in Australia. In 2022, n = 307 non-athlete Australian adults (18-65 years) completed an online cross-sectional survey including closed-ended (consumption patterns, factors, and exercise participation) and open-ended questions (reasons for consumption, risk perception, and side effects experienced). Descriptive statistics (frequency and percent) described the sample. Ordinal logistic regression was used for univariate associations and a multivariate model was used to determine relationships between sports food consumption proxy and significant univariate associations. The themes were analysed via inductive thematic analysis using NVivo 14. Females consumed sports foods most frequently, 65% of participants consumed three or more sports foods, and participants with higher sports food consumption/frequency were less likely to perceive risks or experience side effects. The main reason for consumption was protein intake, digestion/stomach issues were the main perceived risks, and the main side effect was bloating. Despite understanding the risks and side effects, non-athlete consumers continue to use numerous sports foods, which appear to be influenced by sociodemographic factors and packaging labels. Tighter regulation of packaging-label information would ensure safer and more informed consumption.

Supplementation for Performance and Health in Patients with Phenylketonuria: An Exercise-Based Approach to Improving Dietary Adherence

Supplementation is crucial for improving performance and health in phenylketonuria (PKU) patients, who face dietary challenges. Proteins are vital for athletes, supporting muscle growth, minimizing catabolism, and aiding muscle repair and glycogen replenishment post-exercise. However, PKU individuals must limit phenylalanine (Phe) intake, requiring supplementation with Phe-free amino acids or glycomacropeptides. Tailored to meet nutritional needs, these substitutes lack Phe but fulfill protein requirements. Due to limited supplement availability, athletes with PKU may need higher protein intake. Various factors affect tolerated Phe levels, including supplement quantity and age. Adhering to supplement regimens optimizes performance and addresses PKU challenges. Strategically-timed protein substitutes can safely enhance muscle synthesis and sports performance. Individualized intake is essential for optimal outcomes, recognizing proteins' multifaceted role. Here, we explore protein substitute supplementation in PKU patients within the context of physical activity, considering limited evidence.

Smoothies Marketed in Spain: Are They Complying with Labeling Legislation?

There is no legal definition of a smoothie, so the European legislation applicable to its labeling is that of fruit juice. The smoothie market has grown in recent years, as it can include a wide variety of ingredients: fruits, fruit purees, honey, milk and vegetable milks, vegetables, herbs, cereals, cereal flours, seaweed, and crushed ice. In this study, 57 smoothies were reviewed. All of them were purchased in supermarkets and classified into eight types according to the main ingredients. Fifteen legal statements/items were reviewed on the pack labels: eleven mandatory and three optional. Moreover, nutrition labels, nutritional claims, images, marks, and other symbols were also reviewed. Only 22.8% of the samples complied with EU and Spanish labeling legislation. More incorrectness was related to the name of the food and the fruits included as main ingredients; other errors related to the allergy/intolerance statements, and some nutritional claims concerning vitamin C were also detected to a lesser extent. General advice is provided for consumers to interpret smoothie labels correctly. Lawmakers should amend legislation to accept the term "smoothie" as a legal name.

Authentication of protein, fat, carbohydrates, and total energy in commercialized high protein sports foods with their labeling data

The popularity of high-protein sports food items among athletes and the bodybuilding community has risen dramatically. This study aimed to authenticate the reported per serving food label content of protein, fat, carbohydrate, and total energy in commercially available high-protein sports foods available in Egyptian markets. A cross-sectional study was performed on a total of forty-five samples of nine products that included protein bars, cookies, vegan bars, puffs, whey protein, protein drinks, peanut butter, pancake mix, and Greek yogurt. Protein and fat analysis were done according to Kheldahl and Folich methods, respectively, while carbohydrate was calculated by difference. Total energy was calculated according to their content. A significant (p < 0.001) difference was found between the laboratory-assessed content and the reported food label values in protein, carbohydrate, and energy. Protein sport food products had significantly lower protein content (11.6 ± 4.67) obtained from laboratory measurement than the label reported value (17.17 ± 7.22). The fat content in vegan protein was 149.3% higher than the label values (1.67 vs. 0.67 g/serving). The mean fat content per serving of 30 out of 45 samples was significantly higher than the food label values in the bar (37.8%), puffs (32.7%), vegan protein (149.3%), and protein drinks (28.6%). These differences may result in compromised performance and undesired fat gain, as opposed to a desired increase in muscle mass, which could compromise the desired impact of the consumed sports foods.

Sports foods are not all they shake up to be. An audit of formulated supplementary sports food products and packaging in Australian retail environments

Objective

To determine store availability, total number of products, and types of Formulated Supplementary Sports Foods in Australia, along with their stated nutrition content, sweeteners added, total number, and type of claims displayed on the packaging.

Design

A cross-sectional, visual product audit of mainstream retailers.

Setting

Supermarkets, pharmacies, health food stores, and gym/fitness centres.

Results

A total of 558 products were captured in the audit, 275 of which displayed the correct mandatory packaging attributes. Three categories of products were identified, based on the dominant nutrient. Only 184 products appeared to display the correct energy value based on the listed macronutrient content (protein, fat, carbohydrate, dietary fibre). The stated nutrient content was highly variable across all product subcategories. Nineteen different sweeteners were identified, with most foods containing only one (38.2%) or two (34.9%) types. The predominant sweetener was stevia glycosides. Packages displayed multiple claims, with a maximum of 67 and minimum of 2 claims. Nutrition content claims were most frequently displayed (on 98.5% of products). Claims included regulated, minimally regulated and marketing statements.

Conclusion

Sports food consumers should be provided with accurate and detailed on pack nutrition information, to ensure informed choices are made. However, this audit showed multiple products which did not conform to current standards, appeared to provide inaccurate nutrition information, contained multiple sweeteners, and displayed an overwhelming number of on-pack claims. The increase in sales, availability, and products available in mainstream retail environments, could be impacting both intended consumers (athletes), and general non-athlete population. The results indicate underperformance in manufacturing practices which preference marketing over quality and stronger regulatory approaches are needed to protect consumer health and safety, and to prevent misleading consumers.