Pre-workout supplements marketed in Brazil: Caffeine quantification and caffeine daily intake assessment

Development of a Caffeine Content Table for Foods, Drinks, Medications and Supplements Typically Consumed by the Brazilian Population

Background: The lack of a national table informing the caffeine contents in foods, drinks, dietary supplements, and medications sold in Brazil added to the noncompulsory disclosure of caffeine contents on labels of food products makes it difficult to estimate caffeine consumption in the Brazilian population. Therefore, this study aimed to develop the Brazilian Caffeine Content Table (BraCaffT). Methods: A systematic search for caffeine levels in foods, drinks, recipes, supplements, and medications was performed through a literature review, afterward collecting data from the United States Department of Agriculture Food Data Central, information from manufacturers’ and websites, and the Brazilian official medication guide. Subsequently, data systematization was performed in a spreadsheet with standardized values presented in mg of caffeine per 100 g or 100 mL of food or drink and a capsule or pill for medications and some dietary supplements. Results: The BraCaffT presents 57 items, divided into 11 categories: coffees, teas and infusions, cocoa powder, chocolates, cocoa-based beverages, desserts, soft drinks, energy drinks, guaraná powder, dietary supplements, and medications. Conclusions: The BraCaffT emerges as an instrument of great relevance and wide applicability in clinical contexts, in academic research, and as a database for the Brazilian population to better understand the amounts of caffeine in foods, drinks, dietary supplements, and medications consumed daily favoring a safe intake.

Caffeine content of energy drinks marketed in Brazil

Energy drinks represent a multibillionaire industry that has been growing continuously worldwide. These drinks are especially consumed by young people, athletes, and military personnel due to their claimed "boost" effects. However, there have been concerns about their consumption since incompatibilities regarding the accuracy of the declared caffeine content of these drinks have been reported. Therefore, in this study we have developed a fast and simple method to quantify caffeine in energy drinks. Sample preparation consisted of a dilute-and-shoot process, and analyses were performed by gas-chromatography with nitrogen-phosphorus detector (GC-NPD). The method was applied to quantify caffeine in 37 energy drinks marketed in Brazil. Compared to the labeled caffeine content, 84% of the tested drinks presented caffeine levels in accordance with the specifications. The determined caffeine concentrations ranged from 10 to 67 mg/100 mL, with an average value of 31 mg/100 mL. According to the recommended serving size, no drinks exceeded the safe caffeine daily intake for the general population (400 mg). These findings are more favorable than the results of similar studies. Nevertheless, to avoid caffeine intoxication, energy drink consumers should be aware of three aspects. First, they need to avoid consuming multiple serving doses in short periods of time. Additionally, some energy drinks are labeled as "nutritional supplements", so they may present much more caffeine than similar products commonly regulated as beverages. Finally, despite the growing interest in energy drinks, their consumption by children and early adolescents is being discouraged by the health authorities.