2024-07-28 07:55:56
The answer to this question is more complicated than one might think. Different types of food are broken down and absorbed by the body at different rates, so some parts of the meal may enter the large intestine while other parts are still in the stomach. According to Colorado State University (USA).it is also common for healthy people to digest food at slightly different rates.
The researchers conducted studies in which they measured “gut transit time”—how long it takes for a substance to pass through the entire digestive tract—using ingestible capsules that can be tracked during their journey. These studies show that it takes between 0.4 and 15.3 hours for food to pass through the stomach and 3.3 to 7 hours through the entire small intestine. The rest of the undigested food then enters the large intestine, where it can stay for about 15.9 to 28.9 hours, according to a 2023 study. in a review published in the Journal of Clinical Medicine.
Foods that are high in dietary fiber, protein, complex carbohydrates, and fat tend to take longer to digest than foods that are low in these nutrients, says Dr. Nina Nandy, a Texas-based gastroenterologist and spokeswoman for the American Gastroenterological Association.
“Fiber adds bulk to food, which slows down the movement of food through the digestive tract,” she says. “Heavily processed foods are digested more quickly because they lack this nutrient.”
Meanwhile, the stomach and small intestine, while able to process less nutrient-dense foods relatively quickly, take longer to break down high-protein and high-fat foods into nutrients that the body can use.
Also, complex carbohydrates – such as those found in whole grains, legumes and starchy vegetables – take longer to digest than simple sugars. This is because complex carbohydrates are made up of long, complex chainsmade up of three or more sugar molecules – whereas simple sugars only have one or two sugars.
“Before absorbing complex carbohydrates, the body must break them down into simple sugars,” Nandy said. Fiber is a complex carbohydrate that does not break down at all.
Lifestyle factors also affect intestinal transit time. Thorough chewing and hydration can help speed up the digestion process by increasing the surface area of food for digestive enzymes to work on – and softening food particles. In addition, “exercise helps increase intestinal motility and stimulates peristalsis, which is the rhythmic contraction of the digestive muscles,” says N Nandy. On the contrary, peristalsis may slow down during periods of inactivity.
A person’s age and stress levels can also affect digestion. As adults age, they tend to produce less stomach acid and digestive enzymes, and their bowels become less mobile. “Stress and anxiety can also prolong intestinal transit time, as intestinal motility changes and blood flow to the digestive tract decreases,” explains the doctor. An “upset stomach” indicates the activation of the “fight or flight” system, which normally suppresses digestion in the stomach and small intestine while stimulating the large intestine.
And finally, certain medical conditions and medications can speed up or slow down digestion. For example, Diabetes mellitus is the most common cause of gastroparesis or “delayed gastric emptying” causes food to stay in the stomach for a long time.
Some medications, including opiates and anticholinergics, which suppress the nerve signals responsible for involuntary muscle movements, can slow down intestinal transit and cause constipation, Nandy says.
Parengta pagal „Live Science“.
2024-07-28 07:55:56