It is a disease affecting the manner in which the body handles digested carbohydrates. If neglected, diabetes can cause extremely severe health complications, ranging from blindness to kidney failure.
Around eight percent of the population in the United States has diabetes. This means that around sixteen million people have been diagnosed with the disease, based only on national statistics. The American Diabetes Association estimates that diabetes accounts for 178,000 deaths, as well as 54,000 amputees, and 12,000-24,000 cases of blindness annually. Blindness is twenty-five times even more common among diabetic patients in comparison with nondiabetics. If current trends continue, by the year 2010 complications of diabetes will exceed both heart disease and cancer as the leading cause of death in America.
Diabetics have a high level of blood glucose. Blood sugar level is regulated by insulin, a hormone secreted by the pancreas, which releases it in response to carbohydrate consumption. Insulin causes the cells of the body to absorb glucose from the blood. The glucose then serves as fuel for cellular functions.
Traditional diagnostic standards for diabetes have been fasting plasma glucose levels greater than 140 mg/dL on 2 occasions and plasma glucose greater than 200 mg/dL following a 75-gram glucose load. However, even more recently, the American Diabetes Association lowered the criteria for a diabetes diagnosis to fasting plasma glucose levels equal to or higher than 126 mg/dL. Fasting plasma levels outside the normal limit demand further testing, usually by repeating the fasting plasma glucose check and (if indicated) initiating an oral glucose tolerance test.
The many symptoms of diabetes include excessive urination, excessive thirst and hunger, sudden weight loss, blurred vision, delay in healing of wounds, dry and itchy skin, repeated infections, fatigue and headache. While suggestive of diabetes, these symptoms can also be caused by other factors, and therefore anyone with symptoms suspicious of the disease should be tested.
There are 2 different varieties of diabetes.
Type I Diabetes (juvenile diabetes, also known as insulin-dependent diabetes): The cause of type I diabetes starts with pancreatic inability to make insulin. This causes 5-10% of cases of diabetes. The pancreatic Islet of Langerhans cells, which secrete the hormone, are destroyed by the patient’s own immune system, probably because it mistakes them for a virus. Viral infections are believed to be the trigger that sets off this auto-immune disease. Type I diabetes is most prevelant in the caucasian population and has a hereditary component.
If untreated, Type I or juvenile diabetes can lead to death within two to three months of the onset, as the cells of the body starve because they no longer receive the hormonal prompt to absorb glucose. While a great majority of Type I diabetics are young (hence the term Juvenile Diabetes), the condition can develop at any age. Autoimmune diabetes is diagnosed by an immunological assay which shows the presence of anti-insulin/anti-islet-cell antibodies.
Type II Diabetes (non-insulin dependent diabetes, also known as adult onset diabetes): This diabetes is a consequence of body tissues becoming resistant to the effects of insulin. It accounts for 90-95% of cases. In many cases the pancreas is producing a plentiful amount of insulin, however the cells of the body have become unresponsive to its effect due to the chronically high level of the hormone. Finally the pancreas will exhaust its over-active secretion of the hormone, and insulin levels fall to beneath normal.
A tendency towards Type II diabetes is hereditary, although it is unlikely to develop in normal-weight individuals eating a low- or even moderate-carbohydrate diet. Obese, sedentary individuals who eat poor-quality diets built around refined starch, which constantly activates pancreatic insulin secretion, are prone to develop insulin resistance. Native peoples like North American Aboriginals, whose traditional diets never included refined starch and sugar until these items were introduced by Europeans, have very high rates of diabetes, five times the rate of caucasians. Blacks and hispanics are also at higher risk of the disease. Though Type II diabetes isn’t as immediately disastrous as Type I, it can lead to health complications after many years and cause serious disability and shortened lifespan. As with Type I diabetes, the condition develops primarily in a certain age group, in this case patients over forty (which is why it’s typically termed Adult Onset Diabetes); however, with the rise in childhood and teenage obesity, this condition is being seen for the first time in school children as well.
If treatment is neglected, both Type I and Type II diabetes can lead to life-threatening complications like kidney damage (nephropathy), heart disease, nerve damage (neuropathy), retinal damage and blindness(retinopathy), and hypoglycemia (drastic reduction in glucose levels). Diabetes damages blood vessels, especially smaller end-arteries, leading to very severe and premature atherosclerosis. Diabetics are prone to foot problems because neuropathy, which afflicts about ten percent of patients, causes their feet to lose sensation. Foot injuries, common in day-to-day living, go unnoticed, and these injuries cannot heal because of atherosclerotic blockage of the microscopic arteries in the foot. Gangrene and subsequent amputation of toes, feet or even legs is the result for many elderly patients with poorly-controlled diabetes. Usually these sequelae are seen sooner in Type I than Type II diabetes, because Type II patients have a small amount of their own insulin production left to buffer changes in blood sugar levels.
Type I diabetes is a severe disease and there is no known permanent cure for it. Nonetheless, the symptoms can be controlled by strict dietary monitering and insulin injections. Implanted pumps which release insulin immediately in response to changes in blood glucose are in the testing stages.
In theory, since it induced by diet, Type II diabetes should be preventable and manageable by dietary changes alone. However, as so often happens, clinical theory is defeated by human nature in this case, as many diabetics (and many obese people without diabetes) find it personally impossible to lose weight or even stick to a diet free of starchy, sugary junk food. So Type II diabetes is frequently treated with drugs which restore the body’s response to its own insulin, and in a few cases injections of insulin.