Glucose Toxicity

Glucose toxicity refers to the adverse effects of higher than normal concentrations of glucose on cells and tissues. Most commonly, glucose toxicity is defined in terms of the ability of excess glucose to impair insulin secretion and action, resulting in a vicious cycle of worsening glycemic control in diabetes mellitus. Use of the term has expanded to encompass other effects of hyperglycemia, such as the complications of diabetes. It is suggested that “glucose toxicity” be reserved for adverse effects of high glucose concentrations that are specific for glucose or its metabolites (i.e., are not reproduced by hyperosmolality). It should also be kept in mind that some evidence suggests that the word “toxicity” may be misleading in that some of the ultimately harmful effects of excess glucose may represent normal physiologic responses rather than “poisoning” of cells by nonphysiologic mechanisms.