Diabetes is a disease where the body has inability to mange the blood glucose levels. This is either because there is insufficient insulin (type 1 diabetes) or the body becomes resistant to the insulin that is being produced. Diabetes has a profound impact on almost all the functions of the body. Diabetes does have a significant affect on metabolism too.
In the metabolism of those who are not diabetic, sufficient insulin is released to metabolize the glucose. The carbohydrates and the proteins are released into glucose. The carbohydrates are broken down into glucose by various enzymes of the digestive system. The insulin is released in two different phases.
When the glucose enters the blood stream, there is phase 1 release of glucose. For this the body uses stored insulin. The glucose is used for providing energy for various functions of the body cells. The excess glucose is stored in muscles and liver as glycogen. The remaining glucose gets stored as fats. The protein digestion is a much slower process and it releases glucose too. The phase 2 insulin is released when the pancreas produces new insulin. When the blood sugar level falls down, glucagon is released to convert the glycogen to glucose.
Effect on Metabolism in Type 1 Diabetes
In type 1 diabetes, the body hardly produces insulin and is dependent on the supply of insulin through injections or pumps. The amount of insulin delivered should match the amount and timings of glucose that enters the blood stream, for this mechanism to duplicate that what occurs in the body.
The short acting insulin acts like phase 1 insulin and the long acting insulin like phase 2 insulin. Practically, there is often not a correct co ordination between the insulin delivery and glucose entry into the blood. So there may be high or low blood glucose levels. Type 1 diabetics too have the chances of developing insulin resistance.
Effect of Metabolism in Type 2 Diabetes
Type 2 diabetics have insulin resistance, that is cells do not respond to insulin. The insulin is released as in phase 1. However due to resistance all the insulin is not used properly to metabolize the glucose that enters the blood stream. As a result large amount of glucose stays back in the blood.
The body has to depend on the phase 2 insulin now. The body has to wait for the beta cells in the pancreas to produce new insulin. More insulin will be needed by the body because of insulin resistance. Meanwhile, the blood glucose levels will rise very high. The beta cells working harder to produce new insulin, could fail due to overwork.
If there is sufficient gap between two meals, the body gets some time to process the blood glucose levels. But consumption of carbohydrates too soon, will release even more glucose and strain the metabolic system. In type 2 diabetics, they are often obese people and are used to eating large amounts of food. This excess food is stored as fat in the muscles. The excess fats causes insulin resistance in the body. The excess insulin produce by beta cells in response to phase 2 also causes insulin resistance.
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