Artificial sweeteners, specifically aspartame, are present in everyday modern diets due to their low-calorie content and high level of sweetness. They are often used as sugar substitutes to promote weight loss and manage diabetes. Despite their widespread use and approval by regulatory bodies such as the U.S. Food and Drug Administration (FDA), concerns about the safety and potential carcinogenicity of artificial sweeteners persist. This research paper delves into the controversy surrounding aspartame, which was classified as possibly carcinogenic to humans by the International Agency for Research on Cancer (IARC) in 2023. By reviewing literature and analyzing studies published between 2000 and 2024, this paper explores aspartame’s metabolism in the human body, its by-products, and its biological effects. The article also delves into a notable experimental study involving male Wistar albino rats that demonstrated significant biochemical changes, histological liver damage, and gene expression alterations at high doses of aspartame, indicating potential cancer risks. The findings underscore the need for further research to clarify the biochemical and molecular mechanisms linking artificial sweeteners to cancer while emphasizing cautious consumption and reevaluation of safety guidelines.