Stomach acid not only helps in the break down of food, but also defends against food poisoning, revealed a new study. Scavengers, or species that eat food at high risk of microbial contamination, have more stomach acids. This acidity allows the stomach to act as a filter, and effectively control which microbes can pass through the stomach to the gut. While human beings are classified as omnivores, human stomachs have the high acidity levels normally associated with scavengers and medical treatments can significantly alter the acidity in a human stomach.
Corresponding author DeAnna Beasley, a post-doctoral researcher at North Carolina State University, said, "We started this project because we wanted to better understand the relationship between stomach acidity, diet and the microbes that live in the guts of birds and mammals. Our idea was that this could offer some context for looking at the role of the human stomach in influencing gut microbes, and what that may mean for human health. To see how feeding behavior was related to stomach acidity, we examined all of the existing literature on stomach acidity in birds and mammals. The findings raise significant questions about how humans have evolved, our species' relationship with food over time, and how modern changes in diet and medicine are affecting our stomachs, our gut microbes and ultimately our health."
The study appears in the Public Library Of Science (PLOS)