Controversial supplements and emerging doping alternatives in sports: A critical review of evidence, safety, and detection challenges

Background: The global rise in sports supplement use has led to the widespread availability of novel compounds marketed as performance enhancers. These include SARMs, NAD⁺ precursors, synthetic peptides, and herbal adaptogens. However, most lack strong scientific validation and carry potential health risks.
Objectives: To critically evaluate the efficacy, safety, regulatory status, and detection challenges of controversial and emerging supplements in sports.
Methods: A narrative review was conducted using literature published between 2010 and 2025, identified via PubMed, Scopus, Web of Science, and regulatory agency sources (e.g., FDA, WADA). Inclusion criteria focused on studies related to ergogenic effects, health outcomes, and legal classification.
Results: SARMs and synthetic peptides are associated with significant health risks, including liver toxicity and hormonal disruption, despite limited clinical evidence supporting their use. NAD⁺ precursors show minor metabolic benefits but remain under regulatory scrutiny. Herbal adaptogens offer mild performance effects yet lack standardization and long-term safety data. Detection of these substances poses major challenges due to chemical variability and limited reference standards.
Conclusion: The growing use of under-researched supplements raises ethical and regulatory concerns in sport. Clearer global standards, stronger clinical trials, and athlete education are essential to ensure safe and fair supplementation practices. Until such measures are implemented, caution is advised regarding the use of these compounds.