Purpose Recent evidence suggests that especially processed foods may lead to undesirable metabolic effects in gut microbiota. The emulsifiers and artificial sweeteners that are added to processed foods may play a role in the progression of the diseases through the modulation of microbiota in mice. In this context, the purpose of this paper is to evaluate the effects of emulsifiers and artificial sweeteners. Design/methodology/approach This paper presents a narrative review of the effects of emulsifiers and artificial sweeteners which are mainly in consumed in the Western diet, to the gut microbiota by mainly focusing on the experimental studies. Findings Although in vivo studies and animal model studies showed various adverse effects of sweeteners and emulsifiers to microbiota, studies should be conducted in humans to investigate the effects of these food additives to human microbiota by making dietary interventions in the context of ethical rules. Originality/value In future, studies will allow us to draw more definitive conclusion whether human population consuming sweeteners and emulsifiers are at risk.