Sucrose intolerance

Sucrose intolerance, also called genetic sucrase-isomaltase deficiency and abbreviated GSID, is the condition in which sucrase-isomaltase, an enzyme needed to digest sucrose, which is table sugar, and starch such as that in grains, is either not produced or is produced in a partly or wholly non-functional form in the small intestine. All people with GSID lack fully functional sucrase, while the activity of isomaltase can range from minimal to almost normal. The Wikipedia lead suggests that residual isomaltase activity may explain why some patients tolerate starch in their diet better than others with the same deficiency. This entry records the source description and is not medical advice.