The absorption of most nutrients occurs in the small intestine, while water absorption occurs mainly in the large intestine, which is the final part of the intestinal tract.
However, before being absorbed, food needs to be broken down into smaller parts, process that starts from chewing. Then stomach acid helps to digest proteins and as food passes through the entire intestine, it is digested and absorbed.
Absorption of nutrients in the small intestine
The small intestine is where most of the digestion and absorption of nutrients occurs. It is 3 to 4 meters long and is divided into 3 parts: duodenum, jejunum and ileum, which absorb the following nutrients:
- Vitamins: A, C, E, D, K, B complex;
- Minerals: iron, calcium, magnesium, zinc, chlorine.
Ingested food takes about 3 to 10 hours to travel through the small intestine.
In addition, it is important to remember that the stomach participates in the process of alcohol absorption and is responsible for the production of the intrinsic factor, a substance necessary for the absorption of vitamin B12 and prevention of anemia.
Absorption of nutrients in the large intestine
The large intestine is responsible for the formation of feces and is where the bacteria of the intestinal flora are found, which help in the production of vitamins K, B12, thiamine and riboflavin.
The nutrients absorbed in this part are mainly water, biotin, sodium and fats made with short-chain fatty acids.
The fibers present in the diet are important for the formation of feces and help the passage of the fecal cake through the intestine, being also the source of food for the intestinal flora.
What can impair nutrient absorption
Pay attention to diseases that can impair nutrient absorption, as it may be necessary to use dietary supplements recommended by the doctor or nutritionist. Among these diseases are:
- Short bowel syndrome ;
- Stomach ulcers ;
- Cirrhosis ;
- Pancreatitis ;
- Cystic fibrosis;
- Hypo or Hyperthyroidism ;
- Celiac disease ;
- Crohn’s disease ;
In addition, people who have had surgery to remove part of the intestine, liver or pancreas, or who use colostomy may also have problems with nutrient absorption, and should follow the recommendations of the doctor or nutritionist to improve their diet. See the symptoms of bowel cancer.