The obesity epidemic gathers growing media attention recently, as overweight and obesity's prevalence keeps rising. This comes along with an increase in the intake of artificial sweeteners in food products. A causal relationship between the consumption of sweeteners and obesity is so far not clear in the medical literature. This paper describes the development of artificial sweeteners in a historical context. It collects epidemiological and experimental evidence that possibly relates the use of artificial sweeteners with weight gain. Finally, these effects are explained based on the neuroscience of food reward, the possible effects of glucose on the metabolism and the association between sweeteners and gut microbiota.