Your gastrointestinal tract, also known as your bowels, or gut, is involved in the process of digesting, absorbing and eliminating food. From top to bottom, your gastrointestinal tract runs 25 feet in length. It takes time for food to travel such a distance, and the amount of time is related to your diet, specifically to the amount of meat and fiber you consume.
Bowel Transit Time
Bowel transit time is the term doctors use to describe how long it takes for food to pass from your mouth to your anus. Bowel transit time varies from person to person. In fact, transit time can even vary in the same individual. This is because the length of time required for food to move through your gut is influenced by dietary factors. Diets higher in fiber are associated with faster passage and bulkier stools, according to MedlinePlus. Average transit times are between 36 and 72 hours, which is a wide range.
Vegetarians tend to have faster transit times than non-vegetarians, according to a study published in the “British Journal of Nutrition” in 1981. In this study, the distribution of transit times for non-vegetarians was between 31 hours and and 96 hours. The transit times for vegetarians ranged from 27 hours to 54 hours. The average transit time for the vegetarian group was nearly 24 hours faster than for non-vegetarians.
The researchers attributed the difference in transit times between vegetarians and meat-eaters to the amount of fiber in the diet. In general, consuming less than 30 grams of fiber per day is associated with slower transit times, while eating more fiber helps move food through your intestines at a more rapid rate. In general, vegetarians consume more fiber than meat-eaters, likely because plant-based foods make up a greater part of the vegetarian diet. Plant foods are the only sources of fiber.
Other reasons may explain the delay in transit time experienced by meat eaters relative to vegetarians. One has to do with the amount of fat you eat. According to the textbook “Biochemistry,” fattier foods send signals to your stomach to slow emptying. This is because fat is a relatively complex molecule that requires larger periods to digest than, for example, carbohydrates. Animal products such as meat, dairy and eggs typically contain higher amounts of fats than fruits, vegetables and grains.