Which of the following best describes an issue with mass market supplements?

Mass market supplements often come with the concern of contamination due to the lack of stringent quality control measures in large-scale manufacturing. These products can sometimes be produced in facilities that do not adhere to good manufacturing practices, leading to the potential inclusion of harmful substances or unlisted ingredients. This contamination can occur from various sources, including cross-contamination with other products, the use of low-quality raw materials, or inadequate testing of final products.

Choosing mass market supplements might expose consumers to products that do not meet their safety or efficacy expectations due to such contamination. Recognizing this issue is crucial for personal trainers and consumers alike, as it emphasizes the importance of quality over quantity when selecting supplements.

In contrast, the other options do not reflect the general concerns regarding mass market supplements; they may suggest characteristics or features that are not typically associated with these products. For instance, mass market supplements are generally not customizable to individual needs, which is a feature more commonly found in higher-quality or specialized supplements. Similarly, claims about being perfectly labeled are often flawed, as many mass-market products can be misleading or lack sufficient detail on their labels. Over-formulation is also not a universally accurate criticism; while some products may have unnecessary ingredients, others may simply meet the standard expectations without being