A very high protein diet such as this body builder diet is likely to leave Reuben feeling…

➤ Why does a high-protein, low-fiber diet cause constipation?
High-protein diets often displace fiber-rich foods and reduce stool bulk. People on these diets may also drink less water and eat fewer fermentable carbs that feed healthy gut bacteria. Slower transit, lower stool moisture, and shifts in microbiota combine to make bowel movements less frequent and harder to pass.