An Army study shows that MREs reduce the number of frequent bowel movements. In other words, as soldiers look out for No. 1 while on duty, they find it harder to go No. 2.

The report published in The Journal of Nutritional Biochemistry states that a group of 60 people—a combination of military and civilians—participated in the study over a 21-day period. Part of the group chowed down on MREs two to three times a day, while the remaining participants continued their normal diets.

The volunteers then provided their gastrointestinal data to the U.S. Army Research Institute of Environmental Medicine. This included daily food logs, and researchers also collected samples of blood, urine and feces. Researchers analyzed the data from 2015-2017 and found that those who feasted on their regular diets had an average of one more bowel movement per week than those who were committed to eating MREs.