A Primer on Diabetes

Diabetes mellitus, commonly known as diabetes, is one of the world’s oldest known diseases. A recent news report cites that "researchers at the Atlanta-based Centers for Disease Control and Prevention (CDC) said the prevalence of diagnosed diabetes in the U.S. rose rapidly across all regions, demographic groups and in almost every state during the past decade. Diabetes is the nation’s seventh leading cause of death, accounting for more than 300,000 premature deaths every year, the CDC said. About 800,000 new diabetes cases are diagnosed annually".

Diabetes mellitus is caused either by a lack of the hormone insulin (Type I diabetes) or the body's inability to use insulin (Type II diabetes also known as maturity-onset diabetes). Type II diabetes is often triggered by obesity, stress and a sedentary lifestyle. The CDC attributes the phenomenal increase in diabetes cases to the growing prevalence of obesity and decline in physical activity.

  • Increase in diabetes cases between 1990 - 1998 was 33%
  • For People between 30-39 years of age the increase was 70%
  • For people between 40-49 years of age the increase was 40%

Diabetes Prevalence By Age

DIABETES PREVALENCE BY AGE

Type I, also called juvenile onset diabetes or insulin dependent diabetes mellitus (IDDM) accounts for about 10% of the total cases of the disease and afflicts the sufferers quite early in life. IDDM is caused by an individual’s inability to make insulin. Type II  or maturity onset diabetes, also called non-insulin dependent diabetes mellitus (NIDDM), accounts for almost 90% of the diabetes cases. It is associated with a defect in insulin secretion as well as insulin resistance. Individuals who are abdominally obese (central obesity) tend to have diminished capacity to utilize glucose. They also have high levels of circulating free fatty acids (which impairs glucose metabolism) and a low number of insulin receptor sites.

Depending upon the nature of the disease, insulin and certain synthetic drugs like sulphonylureas, biguanidines and acarbose are widely used in its treatment. Before the discovery of insulin by Frederick Banting and Charles Best in 1921, patients with severe cases of diabetes did not survive. Today, although seldom fatal, diabetes is a dreaded disease on account of the related complications. Careful management of diabetes, including control of high blood pressure, can delay some of the serious complications associated with the condition, which include eye diseases, disease of the peripheral blood vessels and kidney failure. In recent years, evidence of cases of "insulin resistance" and the occurrence of side effects from prolonged administration of conventional drugs have triggered the search for safe and effective alternatives. Several plant extracts and isolated phytochemicals have been examined for antidiabetic activity with a view to identify alternative treatment strategies for diabetes. It has been observed that certain resistant cases of diabetes that do not respond well to conventional drugs often respond well to supplementation with natural remedies.

Diabetes is a chronic disorder characterized by high blood sugar levels and abnormal metabolism of carbohydrate, protein and fat. The disease is a result of the failure of the body to control blood sugar levels adequately. The normal fasting blood sugar levels are in the range of 75-115 mg/dl (milligrams per deciliter of blood). After a meal, the body  tightly regulates increases in blood sugar to a level not exceeding 180 mg/dl in people without diabetes.

In a normal person, food which is made up of protein, carbohydrate and fat is digested by the enzymes in the digestive tract. Glucose, a simple sugar is an important end product of digestion. It is absorbed into the bloodstream and transported to the various cells in the body where it is utilized as a fuel to provide energy for the various life activities. Insulin is a hormone which acts as a key that opens the doors of the cells to allow glucose to enter. Insulin is produced in the body by beta cells, specialized cells located in the islets of langerhans of the pancreas.

Delta Cell

The islets of langerhans are little islands of cells, named after their discoverer, Paul Langerhans. The islets of Langerhans contain three types of cells that help in glucose metabolism: alpha cells which make glucagon; beta cells which produce insulin; and delta cells which secrete somatostatin, a hormone which regulates the production of insulin and glucagon.

Normally, insulin and glucagon regulate blood glucose levels, causing almost all carbohydrate and about 50 to 60 percent of protein to be converted into glucose. Glucose is consumed as fuel by almost every type of body cell. In a person suffering from type I diabetes, there is an insufficient or no supply of insulin. In type II diabetes, insulin may be present in sufficient quantities, but it is unable to unlock the doors of the cells. In the normal case, insulin "fits" on to specific sites called insulin receptors located on the surface of the cell (the key holes) and unlocks the "doors" to let glucose enter. If the insulin cannot fit in properly due to lack of insulin receptors on the cell surface, the "doors" remain locked, causing a condition called insulin resistance. In such cases of diabetes, administration of insulin does not help because there are few receptor sites. If the doors of the cells remain unopened, due to lack of insulin or difficulty in utilizing insulin, glucose cannot enter the cells and remains in the blood. This causes increases in blood sugar levels even if no food is eaten.

Urine sugar levels increase when some of the excess blood sugar is excreted. The body begins to use alternative fuel souces (e.g. body fat and protein) for energy.  The patient therefore loses weight, tires easily and has an increased appetite (polyphagia).

Excess glucose in the blood is harmful too. Sugar accumulation in the blood results in increased work load on the kidneys and increased sugar levels in the urine. The sugar enters the urine in solution form, draining water from the cells. This causes an increase in the volume of urine which triggers  frequent urination (polyuria), and induces thirst (polydipsia) in the patient. High blood sugar levels over protracted periods of time causes "glycation" of key body proteins inducing secondary symptoms such as retinopathy which may lead to blindness, neuropathy (nerve degeneration) which may lead to gangrene, and nephropathy which may lead to kidney malfunctions.