What is the small intestine made of? How does it work?
The small intestine is part of the digestive system. The small intestine is designed to absorb digested food. It is about 1.5 meters long. The small intestine has three parts, the duodenum, jejunum, and ileum. It also has villi which are small finger-like protrusions that help with the absorption of nutrients into the body. The epithelial lining also helps with nutrient absorption.
The small intestine has villi which are small finger-like protrusions that help with the absorption of nutrients into the body. There is also an epithelial lining in the small intestine which helps with nutrient absorption. The muscle layer of the small intestine wraps around to form a circular shape, called peristalsis, which pushes the food through the small intestine.
The small intestine is designed to absorb digested food
The small intestine is designed to absorb digested food through its extensive surface area exposed to the lumen. This exposed surface area is increased by the villi which are finger-like projections of intestinal epithelial cells (enterocytes). Enterocytes are connected via tight junctions between one another; this barrier lacks pores, ions, and molecules larger than 9-10 angstroms that can not pass between cells.
This barrier is not present in the paracellular space; it only exists between two enterocytes. The tight junctions inhibit cations, anions, and water-soluble molecules like sugars from passing through the tight junction. This inhibition cannot be overcome by hydrostatic or osmotic pressure (as in the kidney). The only way for substances to pass from the intestinal epithelial cells into the lumen is through specialized protein transporters present on the luminal border of enterocytes.
These protein transporters, such as sodium-glucose co-transporter 1 (SGLT1), use the energy provided by ATP hydrolysis to transport the nutrient cation, in this case, glucose, against its concentration gradient. The diffusion rate of nutrients is also greatly increased through the intestinal epithelial cells due to their high surface area and lack of tight junctions between each cell.
The active transport provided by SGLT1 reabsorbs most dietary sugars; therefore active transport SGLT1 inhibitors are being developed to lower the glycemic response to dietary carbohydrates.
What is the small intestine used for? What is its function?
The small intestine’s main purpose is to absorb nutrients from food so they can be used by your body.
It is a tubular portion of the digestive tract extending from the stomach to the large intestine.
The small intestine is important for digestion and nutrient uptake into the body. The small intestine is designed to absorb digested food. It absorbs nutrients from digested food. It is essential that people have a healthy digestive system because it breaks down food, nutrients are absorbed during digestion, and waste products are sent out of the body. Having healthy intestines is vital for maintaining a healthy body.
Prebiotics & Small Intestine
It is also the ideal place to nourish beneficial bacteria with prebiotics. Prebiotics are dietary fibers that nourish these friendly organisms so they multiply and have a beneficial effect on your health.
Two prebiotic fibers, inulin/oligofructose, and lactulose are combined for a synergistic effect. Inulin/oligofructose is a complex carbohydrate that resists digestion and absorption, so it moves to the lower intestine where friendly bacteria thrive on it. Lactulose has a special ability to increase beneficial bacteria as well as change the pH of the large intestine, inhibiting potentially harmful bacteria.
Inulin/oligofructose causes beneficial bacteria to produce short-chain fatty acids, which have been shown to have a number of health-promoting effects. These include lowering blood cholesterol and triglycerides, reducing the risk of colon cancer, increasing calcium absorption and bone mineralization, preventing constipation and diarrhea, improving lactose digestion in infants, assisting in weight control by reducing the absorption of calories and making you feel full faster, and strengthening the immune system.
Lactulose is also used for the treatment of constipation in infants older than 6 months. When lactulose was fed to preterm infants it prevented necrotizing enterocolitis (a disease where the bowel lining dies due to prolonged lack of blood flow), reduced the number of stools, and increased stool weight. Lactulose was also used in small studies for the treatment of irritable bowel syndrome but it did not show effectiveness.
Lactulose is a sweet-tasting sugar with no nutritional value. It is commonly given to infants because it does not require digestion and draws water from the intestine into the colon. In this form, lactulose is a laxative that helps relieve constipation.*
In young children taking lactulose, side effects may include bloating, gas, abdominal pain, or vomiting. The most serious concern for children with this medicine is a buildup of the chemical in the blood (lactate) which can make a child very ill. Children who develop a high level of lactate in their blood may be treated with sodium bicarbonate or sodium benzoate, but these medications have their own side effects that must be closely monitored by a healthcare provider.
Inulin/oligofructose is not absorbed by the small intestine because of its large size. However, it has been shown to increase calcium absorption, reduce constipation and some types of diarrhea, improve lactose digestion, reduce LDL cholesterol, and increase the mineral content of stools. Inulin/oligofructose has also been shown to have a prebiotic effect on some types of bacteria.*
This article was on the topic of the small intestine. We have learned that the small intestine is designed to absorb digested food. Visit our Health category for more useful articles.