Diabetes Mellitus <ul><li>Diabetes mellitus is a disease in which the body cannot control the LEVELS OF BLOOD GLUCOSE - diabetics have higher than normal levels of glucose in their blood </li></ul><ul><li>This excess glucose is excreted in the urine and can be detected by a simple glucose test (Clinistix) </li></ul><ul><li>Other symptoms include: rapid weight loss , dehydration and frequent urination . </li></ul><ul><li>Diabetes is very dangerous and can result in a sufferer falling into a coma and dying if it is left untreated </li></ul>
<ul><li>Carbohydrates are digested to glucose, which is absorbed into the blood stream and carried to the liver before being distributed to body cells </li></ul><ul><li>If there is TOO MUCH glucose in the blood it is converted to GLYCOGEN and stored in the LIVER until it is needed. If glucose levels are TOO LOW , glycogen is converted back to glucose which can then be used by the body </li></ul>Normal Control of Blood Sugar Levels The receptor cells that monitor the changes in blood sugar levels are found in specialised pancreatic cells called the islets of Langerhans . They secrete two different hormones, INSULIN and GLUCAGON , in response to changes in concentration of glucose in the blood. Insulin is secreted by β cells while glucagon is secreted by α cells.
Type I Diabetes <ul><li>Type 1 or insulin dependent diabetes is caused by the destruction of some (or all) of the β cells in the islets of Langerhans, resulting in TOO LITTLE INSULIN PRODUCTION </li></ul><ul><li>This type of diabetes accounts for 5-10% of all cases of diabetes. It usually occurs in childhood and used to be called early-onset diabetes </li></ul>The treatment for Type 1 diabetes is daily insulin injections
<ul><li>Type 2 or non-insulin dependent diabetes (NIDDM) used to be called late-onset diabetes because it is more common in adults over 40 years of age. (However type 2 diabetes is becoming more common in younger people with some children as young as 13 being diagnosed with this type of diabetes!) </li></ul><ul><li>It is found mainly in people who are overweight or obese; more than 80% of people with Type 2 diabetes are or were overweight. In fact, obesity appears to be the greatest risk factor for NIDDM , although heredity is also thought to play a part since the disease tends to run in families </li></ul><ul><li>People with this type of diabetes have normal (or above normal) levels of insulin, but the target cells have become less sensitive to its effects </li></ul>Type II Diabetes
<ul><li>Insulin works by binding to specific insulin receptors in the cell membranes of its target cells (liver cells, skeletal muscle cells and fat cells). As a result of insulin binding to the receptors, the cell membranes allow glucose to pass through into the cells more easily. People with NIDDM have normal (or above normal) levels of insulin, but the target cells have become less sensitive to its effects. When someone is obese the number of insulin receptors decreases. This reduced number of receptors makes the cells less sensitive to insulin and there is a reduced uptake of glucose by them </li></ul><ul><li>The pancreas tries to compensate for the cells' resistance by producing more insulin. Eventually the β cells stop functioning effectively and insulin production decreases. As a result blood glucose levels rise and diabetes develops. </li></ul><ul><li>Many sufferers of NIDDM can control their blood sugar levels by regular exercise and a carefully controlled diet. If it continues to get out of control, however, insulin injections may be necessary </li></ul>
Effect of Exercise <ul><li>As well as the MANY benefits of exercise already mentioned, physical activity has additional benefits for sufferers of NIDDM </li></ul><ul><li>Exercise improves the uptake of glucose in people with NIDDM. This is thought to be due to an increase in the sensitivity of and an increase in the number of insulin receptors on the cell membranes of target cells, particularly skeletal muscle cells </li></ul><ul><li>This means that individuals are able to control their blood sugar levels more effectively with increased physical activity. This, combined with a carefully controlled diet, can reduce or even remove the need for insulin injections. </li></ul><ul><li>Any kind of increased physical activity is beneficial, but again the general advice of about 30 minutes of moderate exercise most days which is given by most health experts applies to sufferers of NIDDM </li></ul>