Aspartame is one of the most popular sweeteners used worldwide as a sugar substitute. It is found in many foods, including diet drinks, chewing gum, sweets and medicines. Although aspartame is widely used and considered safe by many health organisations, it also raises controversy and concerns about its potential side effects. In this article, we will discuss what the side effects of aspartame consumption are, the mechanisms of action of this sweetener and the latest research on the subject.