NANP Board Practice Exam

What is the relationship between SCFA concentration and luminal pH in the intestine?

1. Direct relationship

2. Inversely related

3. No relationship

4. Randomly fluctuates

The correct answer is: Inversely related

The concentration of short-chain fatty acids (SCFAs) in the intestine has an inverse relationship with luminal pH. As SCFA concentration increases, it tends to lower the luminal pH due to the production of organic acids during fermentation processes conducted by gut microbiota. A higher concentration of SCFAs results in a more acidic environment, which contributes to an overall decrease in the intestinal luminal pH. It's important to understand that the production of SCFAs is a beneficial process, as these acids play essential roles in gut health, including providing energy for colon cells and regulating inflammation. The relationship can be seen as a dynamic balance; when SCFAs are produced more abundantly, they acidify the intestinal environment, impacting various functions such as mineral absorption and microbial balance in the gut.