What causes Type I Diabetes (Juvenile diabetes)?

As mentioned in the previous post, diabetes is characterised by increased levels of glucose in blood. Children almost always develop Type I diabetes (except obese children). As you know, glucose is the source of energy for us. Insulin is necessary for taking up glucose from the blood into the muscles, liver and other parts of the body. Whenever glucose level in blood increases (after eating), insulin is secreted into blood for the absorption of glucose into the liver, muscles etc. This is illustrated in the picture below. Type I diabetes results when our body makes too little/ no insulin.

Insulin is a ‘hormone’ (a special chemical) formed in the ‘pancreas’. Pancreas is a small gland present in our body that lies just behind the stomach. Occasionally, body’s immune system starts attacking it’s own tissues. This is known as ‘autoimmune mechanism’. Even though the exact cause for diabetes in children is not clear, an autoimmune mechanism (where parts of pancreas (islets) which make insulin are destroyed by body’s own immune system) is proposed. Some environmental factors or simple viral illness may trigger this. And also, if there is some one in the family (father, mother or sibling) with childhood diabetes, chances of getting it increases.

When there is no insulin……..

Glucose can not be used for energy. Instead fat is used for energy which in turn will lead to formation of a poisonous (to explain in simple terms) substance called ‘ketones’. Body will try to get rid of excess glucose in the blood by passing it in urine. This makes the child pass urine frequently and as a consequence makes him thirsty. Excess glucose in the blood leads to various complications which will be explained in subsequent posts. Thus, diabetes evolves.

This picture is the summary of what happens in diabetes.