Prediabetes is the state in which some but not all of the diagnostic criteria for diabetes are met. One test is for Impaired Glucose Tolerance (IGT). This and other terms are defined in a Wikipedia Glossary of Diabetes
The US Center for Disease Control (CDC) recognizes this as America’s Largest Epidemic already affecting 57 million living Americans, some in various stages of dysfunction.
The answer is clear: eat real whole foods to get the nutrients your body needs. That will stop the body from driving you to eat and eat. That will allow your stomach to shrink so that you can eat small amounts throughout the day. Your body will love you for it! A whole food is something that grew up and was not processed in such a way as to reduce or distort its natural ingredients. A real wheat grain is whole food but flour is not. A strawberry is whole food but strawberry jam is not. Chicken meat is whole food but deep fried chicken with flour/whatever breading is not.
Treat your family and yourself to whole foods and avoid or reduce the chance of diabetes and other metabolic diseases.