The main function of carbohydrates is to provide us with energy. Digestion of carbohydrates begins in the mouth and during digestion carbohydrates are broken down into simple sugars and absorbed into the bloodstream as glucose. Insulin allows this glucose to enter the cells as an energy source. Depending on the body’s needs, unused glucose is stored as glycogen in the liver and muscles. This is later used or turned into fat. The terms simple and complex refer to the chemical structure of the molecules that make up food.
As the name suggests, these are small, simple connections that break down quickly. As a result, products containing simple carbohydrates provide a quick spike of energy after they are consumed.
Sources of simple carbohydrates include:
Although fruit is a source of simple carbohydrates due to the naturally occurring sugars, fruit is also a good source of fiber. As a result, fruit causes a less high spike in blood sugar than other sources of simple carbohydrates.
Complex carbohydrates are larger compounds that take longer to break down, slowing down digestion and absorption and preventing extreme spikes in blood sugar. These complex carbohydrates contain fiber, which supports gut health and helps us manage our weight and lower cholesterol. The two types of fiber, soluble and insoluble, slow the absorption of sugar into the bloodstream and help prevent spikes in blood sugar to maintain more consistent blood sugar levels.
Sources of complex carbohydrates include:
– Whole wheat products (pasta, bread, wraps)
– Brown rice
– Vegetables such as sweet potato
Whole grains contain three main parts: bran, germ and endosperm. Most of the nutritional value of the grain is in the bran and germ. Grains also contain fiber, antioxidants, vitamins and minerals. When grains are refined, for example to make white pasta or white bread, the bran and germ are usually removed to extend the shelf life of the product. The endosperm contains carbohydrates and proteins and that is usually all that is left. So, the grain no longer contains the fibers that slow down digestion and absorption into the bloodstream. As a result, refined grains cause a faster rise in blood sugar levels.
Ultimately, all carbohydrates are broken down into glucose to be absorbed by the body and used as energy. Foods high in simple carbohydrates such as sugar cause blood sugar levels to rise rapidly, requiring a more coordinated hormonal response (release of insulin) to clear the glucose from the bloodstream. Over time, rapid spikes become harder on the body as the ability to control blood sugar levels continues to decline. This also makes the body less able to produce enough insulin. The insulin that is produced is less effective, which is also called reduced insulin sensitivity and is an important risk factor for type 2 diabetes.
Where to focus on?
Eliminating refined carbohydrates by replacing products such as white bread, wraps and pasta with whole-wheat bread, whole-wheat wraps and whole-wheat pasta can be a first step. Note especially with bread that brown bread is not immediately whole wheat, but darker white bread. It’s always helpful to read the ingredients of the foods you eat.