In 1923, Sir Frederick Grant Banting, a Canadian scholar at the age of 32, was awarded the Nobel Prize for the discovery of insulin, a hormone produced by beta-cells of the pancreas.
Diabetes is a metabolic disease during which insulin production is disturbed, the small amount of which causes hyperglycemia in the body because insulin is responsible for the metabolism of carbohydrates (fats and proteins too), namely for reducing the amount of sugar (glucose) in the blood.
In Europe, by WHO (World Health Organization) 60 million people live with diabetes and every year tens of thousands of them die from this disease. In some countries the number of patients reaches 10-12% of the population.
What happens after a meal?
During a meal, when we provide carbohydrates, they are (faster than proteins or fats) metabolized to easier compounds such as, for example, glucose or fructose. These simple compounds can be quickly absorbed into the bloodstream and provide energy to our body.
We can distinguish two types of carbohydrates, simple and complex. The difference lies in the size of the molecule and its durability. As you can guess, these simple carbohydrates are quickly broken down and we draw energy from them faster, but it also decreases faster. After the distribution of such carbohydrates, we have a leap of energy that ends right away. When decomposing complex carbohydrates, there is no sudden jump of glucose in our bloodstream, but rather slowly released energy that lasts longer.
How energy is released from carbohydrates (ie. how quickly they are broken down into glucose and absorbed into the bloodstream) is called the glycemic index (GI). The higher the GI, the higher the concentration of glucose in the blood after a meal.
Glucose in the blood stimulates the production of insulin, whose task is to lower the concentration of this glucose. When insulin is produced, glucose is captured in the liver, where, also the synthesis of glycogen happens, which is transported to the muscles, where, during exercise, it is a reserve source of energy.
Why a backup energy source?
When the amount of sugar in the blood drops, and we still need energy, we do not have access to food, glycogen comes to help, then this molecule is broken down and we take energy from glycogen during long gym exercises.
The glucose drop in blood is called hypoglycaemia. This decrease causes the pancreas to release the hormone – glucagon, which causes the breakdown of glycogen to smaller glucose molecules.
What about GI and diabetes?
The higher the GI, the faster the sugar spike in the blood. We already know that. But the greater the sugar surge in the blood, the more insulin is produced. Pancreas-producing cells that produce insulin can slowly be destroyed and then lose their ability to secrete this hormone. This condition is called type 1 diabetes. Treatment consists of insulin administration throughout life.
Type 1 diabetes accounts for about 10% of all cases of diabetes. The disease starts between 12-15 year of life. Type 1 diabetes causes a decrease in life expectancy about a dozen or so years.
Type 2 diabetes is characterized by insulin resistance. The pancreatic cells do not lose their ability to produce insulin, but tissues such as muscles or adipose tissue have less sensitivity to its action.
Type 2 diabetes is usually caused by obesity, low physical activity, excess cortisol (stress hormone, excess can be caused by drugs) or genetic factors.
Symptoms of type 2 diabetes are:
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excessive thirst
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urinary frequency
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excessive increase in appetite
Treatment consists of increasing physical activity, reducing obesity, and using a low glycemic diet (low GI food).