I am 39 years old, and I seem to have impaired glucose tolerance with A1cs less than 6%. I had gestational diabetes during two of my three pregnancies, and control difficulty along with pre-eclampsia during the last one really frightened me. My one-hour postprandial sugars are sometimes too high (180+ mg/dl [10 mmol/L]), but my two- and three-hour levels are almost always below 140 mg/dl [7.7 mmol/L]. Are high one-hour postprandial blood sugars harmful? Does anyone know? Is there a recommended diet to follow to keep IGT, type 2 diabetes, and heart disease at bay? I am at the proper weight now, and have been for eight months, but my track record for staying at the proper weight has not been stellar.

You have raised great questions. I am glad someone has educated you about the need to follow a healthy lifestyle after the diagnosis of gestational diabetes. The finite period of time that you are pregnant provides a window into the future that suggests your increase risk for developing type�2 diabetes. Because you have had GDM, you should be regularly screened for type 2 diabetes. hemoglobin A1c is not sensitive enough. However, A1c is the test which has been studied and correlated with microvascular complications. Remember that the A1c represents the average daily blood sugar over the previous three months. The postprandial blood sugars may not be high enough to make it higher. Unfortunately, there are not a lot of data about risk of elevated postprandial blood sugars in patients without diabetes.

Your second question is also good. Recently, the results of the Diabetes Prevention Program (DPP) were released. This was a national study looking at several interventions and their ability to prevent frank diabetes in individuals who were determined to have impaired glucose tolerance. It was found that the most potent prevention therapy was diet and exercise. There is nothing magic about the diet. It is a diet which prevents obesity or allows for weight loss in those who are obese and is limited to less than 30% calories as fat. It also included regular physical activity, which is often overlooked.

It is important to know that even people who have insulin resistance without diabetes are at increased risk for cardiovascular disease. Therefore, consider regular monitoring of your blood lipids (cholesterol, triglycerides, LDL-cholesterol, and HDL-cholesterol), regular exercise, good diet, don’t smoke, consider a daily aspirin, and maintain normal or lowest possible weight.

JTL