Diabetes is common. In the Unisted States alone between one-quarter and one-third of all people are diabetic. Diabetes prevalence is rising quite quickly in developed countries and is a major cause of morbidities such as kidney disease, amputations, and blindness.
Type 1 Diabetes. The first major form of diabetes, known simply as Type 1 diabetes is an autoimmune disease wherein the body's own immune system attacks and destroys the cells within the pancreas that produce insulin, rendering the affected person unable to produce insulin naturally. This type of diabetes was formerly known as Insulin Dependent Diabetes Mellitus, which is an inaccurate term because both major types of diabetes can require insulin treatment. Also known as juvenile diabetes, Type 1 diabetes often begins in childhood. It is fairly rare, accounting for only 5% or so of all diabetes cases. It would be a deadly disease except for the fact that insulin produced external to the body can be manually injected to substitute for what the body can no longer produce on its own. Persons with Type 1 diabetes must learn to periodically check their blood sugar and self-administer insulin shots in order to keep their blood sugar levels normalized. Though diet modifications cannot cure Type 1 diabetes, they are important to follow anyway so as to keep blood sugar swings minimized as much as possible.
Type 2 Diabetes. Type 2 diabetes is different than Type 1 diabetes in that it begins with a gradual decrease in the body's ability to respond to insulin (a condition known as "Insulin Resistance"), rather than an abrupt stoppage of actual insulin production. Insulin resistance occurs when the body is repeatedly subjected to high levels of insulin in the blood stream. After a while the cells do not respond as vigorously to insulin as they once would. At this point it takes a higher level of insulin to get the same amount of glucose into the cells. This can be thought of a little like "the boy who cried wolf." Initially, every time the boy cried out everyone came running quickly and efficiently. However, after running to the child multiple times and finding him completely safe the villagers stopped responding to his calls. Only after the disease has progressed does actual insulin production start to decrease. Though the mechanisms causing Type 1 and Type 2 diabetes are different, the net results are identical; blood glucose levels stay higher than normal and dangerous Hyperglycemia (high blood sugar) can result. Type 2 diabetes, which is linked to obesity and poor lifestyle choices and which often begins in adulthood, is far more common than Type 1 diabetes. It accounts for some 90 to 95% of diabetes cases. It is so common in fact that it has been given the label "epidemic" by the Centers for Disease Control and Prevention. The illness can often be controlled or even in some cases eliminated through careful attention to weight loss, healthy diet and other lifestyle modifications.
In many cases, Type 2 diabetes is preceded by a condition called Pre-Diabetes, which occurs when blood sugar levels are often measurably above normal but not yet in the diabetic range. The American Diabetes Association states that there are millions of Americans with pre-diabetes. Pre-diabetes, and Type 2 diabetes itself are considered to be "lifestyle" illnesses, in that they are associated with unhealthy lifestyle practices such as eating fatty, high-sugar diets, and failing to get regular exercise. With even modest exercise and diet reform, pre-diabetes can often be reversed.
Gestational Diabetes. Gestational diabetes occurs in women in the latter stages of pregnancy, is relatively rare, and generally subsides with the end of pregnancy. As a condition, it is akin to Type 2 diabetes. Women who have experienced Gestational diabetes go on to have an increased risk of developing Type 2 diabetes in later life.