The human gut microbiome is more important to health than most people realize. It is filled with trillions of microbes ranging from fungi to bacteria and viruses. This paper focuses on preservatives and emulsifiers and the effects they have on the gut microbiome. These two food additives affect different types of bacteria differently. Emulsifiers and preservatives increased bacteria that tend to have negative effects on the body, while decreasing beneficial bacteria. This can have many different effects on the body from Crohn's disease to dysbiosis and even increase antimicrobial resistance in bacteria. This review looks to explain why preservatives and emulsifiers have such negative effects, why it is such a relevant and important topic, and alternatives to preservatives or emulsifiers, or ways to mitigate the effects of these two food additives.