Although type 1 diabetes was previously known as childhood diabetes, juvenile or juvenile-onset diabetes this is no longer the case. While type 1 diabetes often first appears in children over the age of 4, and is especially seen with the arrival of early adolescence at around 12 or 13 years of age, it can also appear in adults and is increasingly being seen in people in their late 30s and early 40s, although the onset at this age tends to be somewhat less marked than that seen in children

Type 1 diabetes is caused by the body's inability to produce sufficient insulin. The precise reason for this inability is something of a mystery, although there is almost certainly an underlying genetic cause which is triggered by a combination of different environmental factors.

The body needs insulin for normal metabolism and uses it to transfer glucose, which forms one of the body's main sources of energy and is produced during the process of food digestion, from the bloodstream and into the cells of the body. In healthy people insulin is produced by cells, called beta-cells, within an area of the pancreas but, in cases of type 1 diabetes, these cells become damaged and production either cease or is reduced.

There are around one million Americans suffering from type 1 diabetes, which represents somewhere between 5% and 10% of the total number of Americans suffering both type 1 and type 2 forms of the disease. Each year, in the region of ten thousand new cases of type 1 diabetes are diagnosed in the United States. Type 1 diabetes is more common in men than it is in women and is also more prevalent among non-Hispanic whites, Hispanic Americans and African Americans.

Although not in itself life-threatening, type 1 diabetes accounts for a significant number of deaths, particularly premature deaths, from complications arising out of the condition. These can include cerebral vascular disease, renal disease, heart disease, vascular disease and gangrene in the lower limbs, visual difficulty and blindness.

There are a number of symptoms that can accompany the onset of type 1 diabetes and the most common early symptoms, which result from a buildup of glucose in the blood, are excessive urination, thirst and hunger usually accompanied by tiredness and a lack of energy. In some cases excessive blood sugar can also lead to nausea and blurred vision.

It is also common for the presence of type 1 diabetes to be detected as the result of an emergency condition known as ketoacidosis with the diagnosis being made in a hospital emergency room. Ketoacidosis arises when blood sugar levels reach an especially high level and the body begins to break down fat to get the energy that it needs. This leads to a build-up of chemicals known as ketones in the blood and produces nausea, vomiting and stomach pains. If left untreated the condition will progress and breathing can become increasingly rapid, followed by coma and death.

The main treatment for type 1 diabetes is the regular administration of insulin. As diabetes is however a metabolic disease, diet and exercise can also play a key part in keeping sufferers fit and healthy.