To understand what is going wrong in your body with diabetes, it is important to know how your body works due to the diabetes.

Diabetes Type 1, after a meal
1. The stomach converts glucose from food into simple sugars. These simple sugars can be absorbed from the stomach and gut into the blood.

2. When you see and eat food, the pancreas cannot respond well because the beta cells are damaged. As a result, no insulin is produced. Without insulin, the glucose in your blood cannot enter the body's cells, even though there is enough glucose being circulated.

3. Meanwhile, your cells are in desperate need of glucose, as fuel. Your body will try to increase the amount of glucose in other ways:
a. The glycogen in your liver is converted into glucose (using glucagon, for instance), raising your blood sugar even further, which results in even more glucose being circulated. Some of this you lose through peeing, and because glucose absorbs a lot of fluid you need to pee a lot and frequently. This makes you thirsty and makes you drink a lot too.
b. Fats and proteins in your body are broken down to create glucose. During the break-down of fats, fatty acids are released which are converted into ketones by the liver. Part of these ketones end up in your urine. At that time both ketones and glucose can be found in the urine. The break-down of fats and proteins causes you to lose weight and makes you feel sick, tired, and listless.

4. But there is still no insulin to get all the glucose into your cells. So, you have too little glucose in your cells and too much in your blood, which is harmful and may eventually become life-threatening. The surplus of glucose damages those cells of your body that do not need insulin to absorb glucose (like cells in your kidneys, brain, retinas, and your nervous system). Besides that, too many ketones lower the pH-level of your blood (ketoacidosis). And when you dehydrate from peeing so much, the water deficit will reduce the blood volume and the pH-level of your blood will lower even more. Due to the dehydration combined with the low pH-level of your blood, you could fall into a life-threatening coma, also called a diabetic coma (or diabetic ketoacidosis coma).

Diabetes Type 2, after a meal
1. The stomach converts glucose from food into simple sugars. These simple sugars can be absorbed from the stomach and gut into the blood.

2. The sensitivity of the liver and muscles to insulin is decreased. The liver is no longer reacting properly to insulin, resulting in too little glucose being converted into glycogen, making the blood sugar rises.

3. The moment you see and eat food, the pancreas responds slower than it should. It takes a long time before extra insulin is produced. Because of this, there is less insulin the moment you need it the most.

4. Because of the lack of insulin and the reduced efficiency of insulin, the blood sugar level is too high. The small amount of insulin and the high blood sugar ensure that a small level of glucose still enters the body's cells.

5. The extra glucose results in a lot of glucose entering cells that do not need insulin to absorb glucose (like cells in the kidneys, brain, retina, and nervous system). This causes damage to these cells.