Vitamins are organic compounds vital to life. You can meet your daily recommended intake of each vitamin by eating a healthy well-balanced diet that includes a variety of different foods. Your body absorbs vitamins through the lining of the small intestine. Conditions that affect the digestive tract or the breakdown of food can cause your body to not absorb vitamins.
The body absorbs vitamin B-12, a water-soluble vitamin, through the lining of the small intestine, but this vitamin must first bind to a protein produced by cells in the stomach lining known as intrinsic factor. Enzymes in the gastric acid free vitamin B-12 from the food particles, which allows it to bind to intrinsic factor. The combination of intrinsic factor with B-12 binds to and gets absorbed by receptors lining the small intestine. Pernicious anemia usually occurs due to an autoimmune response in which the cells of the immune system attack and destroy the cells in the lining of the stomach. This results in a decrease in stomach acid and enzymes, allowing vitamin B-12 to remain attached to the food. In addition, antibodies of the immune system bind to intrinsic factor, interfering with the ability of intrinsic factor to bind with vitamin-12, which inhibits the absorption of vitamin B-12.
Gluten is the protein found in wheat, rye and barley. Approximately 1 in every 133 people in the U.S. develops an intolerance to gluten, a medical condition known as celiac disease, according to the National Digestive Diseases Information Clearinghouse. For those people, when they consume foods containing gluten, their immune system reacts by attacking the villi, small finger-like projections, in the small intestines. The villi allow the absorption of vitamins and other nutrients through the lining of the small intestine. Over time, the destruction of the villi inhibits the absorption of vitamins.
Conditions that cause inflammation of the intestines make your body unable to absorb vitamins. Crohn’s disease, one type of inflammatory bowel disease, or IBS, causes inflammation anywhere in the digestive tract, but most commonly affects the lower portion of the small intestine. The cause of inflammation in Crohn’s disease continues to be an area of study, but one theory suggests the cells of the immune system misinterprets both food and bacteria as foreign invaders, causing the inflammation. Vitamin deficiency due to inhibited absorption is a common complication of Crohn’s disease.
Some vitamins are fat-soluble, including vitamins A, D, E and K, meaning they bind to or dissolve in fat. Conditions that affect the absorption of fat inhibit the absorption of vitamins. The liver produces bile, a substance consisting of cholesterol, salts and water, vital to the breakdown and absorption of fat. Liver disease reduces bile production, inhibits fat absorption and prevents the absorption of the fat-soluble vitamins. The pancreas secretes digestive enzymes that join with the bile in the intestines. These enzymes aid in the breakdown of foods such as fat. Pancreatitis, a condition characterized by inflammation of the pancreas, reduces the amount of pancreatic enzymes, which inhibits the breakdown and absorption of fat, leaving the body unable to absorb fat-soluble vitamins.
- Vitamins image by Igor Nikolayev from Fotolia.com
This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.