As of 2005 the CDC estimates that 20.8 million Americans suffer from Diabetes. Type 2 diabetes which accounts for 90-95% of all diagnosed cases, is associated with excessive body fat and obesity. Genetics also play an important role in the development of type 2 diabetes, but the most influential and powerful factor is lifestyle.
Regular exercise and a proper diet can dramatically alter the course of type 2 diabetes by changing how the body relates to blood sugar and insulin. As a person gains more weight, particularly around the abdomen, fat tissue begins to infiltrate the vital organs such as the liver and the pancreas. As this process progresses, chemical signals are produced that prevent our cells from responding to an important hormone called insulin. Insulin is what is responsible for helping to transfer the sugar in our blood (derived from the food we eat and our body’s own sugar manufacturing system) into our cells where it can be used to make and store energy. The end result is a state referred to as insulin resistance; this is when the cells no longer respond to insulin so the sugar is stuck in the blood. Continuously elevated blood sugar levels will eventually cause severe damage to the blood vessels, kidneys and eyes, ultimately leading to heart disease, blindness, kidney failure and poor circulation to the hands and feet.
To understand this process further we need a deeper understanding of how insulin works and why our bodies become resistant to it in the first place.
Insulin was designed to help our bodies store energy, mainly as fat. The release of insulin is primarily triggered by the ingestion of foods that have a high glycemic index. This means that these foods are broken down into glucose at very fast rates. Some examples are white bread, pasta, candy, soft drinks and pastries. Eating diets high in simple carbohydrates (high glycemic foods) will signal the release of high amounts of insulin which will in turn trigger the storage of all that glucose as fat. This is why low carbohydrate diets help us loose weight. When we eliminate the high glycemic foods we limit the amount of insulin produced and our body limits the fat storage process.
This system was first designed to help humans withstand times of famine. When food was plenty, or when we ingested something with a lot of sugar like honey, our bodies knew we could not burn all that energy at once. So it developed a mechanism to store that energy for a later time, as fat. Well now we live in a society of abundance and luckily most of us are not faced with the challenges of famine anymore. We consume so many excess calories in the form of high glycemic foods that our body needs to keep packing on the pounds of fat to store it all somewhere because it still thinks there may be a famine. As we gain more weight, particularly in the abdomen the fat actually starts to infiltrate the organs. This serves as a powerful signal to the body that it certainly does not need to store anymore energy. But instead of decreasing the insulin response as a way of dealing with this, the body signals the cells to become resistant to the effects of insulin. The more resistant the cells become the more insulin that will be produced and a vicious cycle begins.
Have you ever heard that Native Americans are at a much higher risk of developing Type 2 Diabetes? It is true, and the reason is because their heritage is one characterized by extreme times of abundance and then famine. Due to this, their bodies became extremely sensitive to high glycemic foods and are very efficient at storing energy using insulin. When they eat a diet so rich in calories and abundant in sugar (like that of the standard American Diet) their highly sensitive systems go into storage overdrive and they ultimately end up in insulin resistance much quicker than people with other heritages not characterized by feast or famine.