What Is Sugar Malabsorption and How Does It Relate to CSID?
Paula Gallagher, MFN, RD, LD
Malabsorption of nutrients containing proteins, fats, carbohydrates, vitamins, and minerals can occur in an individual and is typically caused by a malfunction of the gastrointestinal tract. Malabsorption can have many different causes, including infections, medications, surgery, or even inflammatory diseases. For those who have inherited Congenital Sucrase-Isomaltose Deficiency (CSID), malabsorption of two carbohydrates known as sucrose and isomaltose occurs.
To understand how carbohydrate malabsorption occurs, let’s take a look at the science behind digestion. In the mouth, our teeth shred carbohydrates into smaller pieces. The carbohydrates then mix with our saliva and salivary enzymes to begin digestion. Once in the stomach, carbohydrates are mixed with gastric juices and liquified.
Although digestion of carbohydrates doesn’t occur in the stomach, the liquification of food is an important step. The liquified food moves into the small intestines where a team of enzymes help the body digest the carbohydrates. The walls of the small intestines produce the enzymes sucrase, lactase, maltase, and isomaltase that are vital to carbohydrate digestion.
Sucrose and isomaltose are sugars that occur naturally in many foods, including bananas, carrots, sweet potatoes , apples, and grains. Sucrose can also be added to foods like cookies, flavored yogurts, and beverages.
Sucrase is the enzyme that breaks sucrose down into two smaller molecules known as fructose and glucose. Once sucrose is transformed into these molecules, the body can absorb them and use them for energy in the body.
Isomaltas e is the enzyme that assists the body in breaking down isomaltose into two molecules of glucose that can be absorbed. Once this disaccharides are broken into two molecules of glucose, the body can absorb them and use them for energy.
As previously mentioned, the two digestive enzymes – sucrase and isomaltase – assist the body in digesting sucrose and isomaltose, respectively. When these enzymes are not present, are present in low levels, or don’t function well, sugar malabsorption occurs.
When the body is unable to break down the sugars sucrose or isomaltose to use them for energy, malabsorption occurs. Instead, sucrose and isomaltose remain intact as they travel through the digestive tract, wreaking havoc as they go. Individuals with the genetic condition called CSID are unable to break down the disaccharides sucrose or isomatose into smaller sugars for absorption. Malabsorption of these dissacharide sugars can cause many symptoms, including chronic diarrhea, gas, bloating, abdominal pain, and even malnutrition.
In summary, malabsorption can occur for many different reasons and with many different nutrients. In many cases, malabsorption occurs due to a malfunction of the gastrointestinal tract. For those who have CSID, malabsorption occurs because of low, absent, or non functioning levels of the two digestive enzymes sucrase and isomaltase, which can cause Sucrose Intolerance that results in many unpleasant gastrointestinal symptoms. If you or your child have chronic diarrhea or other digestive symptoms after eating a meal containing sucrose or isomaltose, you may have CSID. For more information, visit www.sucroseintolerance.com/symptoms.