A Short Primer on Diabetes, Pre-Diabetes, and Blood Sugar Metabolism
A 50-year-old man has some routine blood tests and visits his Doctor, only to be told that his blood sugar is high and that he is at risk of developing Type 2 Diabetes. Sound familiar? It probably does – a recent report estimates that 15% of the population fall into this category.
Sometimes termed ‘Pre-Diabetes’, this condition marks a transition between the normal blood sugar regulation in a healthy person and the development of insulin resistance characteristic of someone with Type 2 Diabetes. Importantly, developing a working understanding of some important terms may help you prevent Type 2 Diabetes.
Blood Sugar (aka. Blood Glucose): Your body prefers to transport energy around as glucose, a type of sugar. Food may be broken down into glucose, as is the case with digestible starch, or it may be broken down into other nutrients and then converted into glucose. Cells throughout the body then take glucose out of the blood stream and internally ‘burn’ the glucose to produce energy.
Insulin: This hormone is produced by cells in the pancreas in response to rising blood glucose - after a meal, for example. Insulin tells cells to take glucose out of the blood. Muscle and fat cells are important targets for insulin because they can take up vast amounts of glucose for short- or long-term storage.
Insulin Sensitivity: After eating, blood glucose levels rise. The body then produces insulin to move glucose out of the blood, thereby restoring healthy blood glucose levels. In people with normal insulin sensitivity, muscle and fat cells efficiently respond to insulin, rapidly reducing blood glucose levels.
Insulin Resistance: Due to many factors, including age, target tissues like fat and muscle become resistant to insulin. In other words, they lose insulin sensitivity and the body must produce more insulin to get cells to respond. Ultimately, increased insulin resistance may lead to the development of Type 2 Diabetes if the body can no longer produce enough insulin to keep blood sugar within a healthy range.
While some factors contributing to insulin resistance are unavoidable, there are others that you can influence. Muscle tissue is normally a major target of insulin and consumer of glucose, but muscles consume relatively less energy in a physically inactive person. Consequently, an inactive body is required to produce more insulin to convince muscle cells to take glucose out of the blood stream. This contributes to insulin resistance. However, physical activity can reverse insulin resistance by creating demand for glucose and increasing insulin sensitivity in muscle cells.
Weight loss can similarly reduce insulin resistance, and since increased activity significantly aides in weight reduction programs, exercise is often the most prescribed advice for patients with pre-diabetes. Nutrition also plays an important role and many pre-diabetics are also advised to make significant changes to their diet.
Eating more fiber is an effective way to improve your diet. Fiber adds bulk to your food, helping provide a sense of fullness, but is not converted to glucose and therefore will not raise blood sugar levels. As novel research results are published, it will be interesting to see how the inclusion of fermentable fiber can factor into a healthier lifestyle.