There are a range of different symptoms in people with diabetes. They may feel thirsty, pass a large amount of urine, wake up overnight to pass urine, lose weight and have blurred vision. Patients are vulnerable to infections such as thrush and may present with this. Particularly in type 2 diabetes, patients may not be aware of their diabetes for several years and a diagnosis may only be made when they seek treatment for diabetes-related complications such as foot, eye or kidney problems. Some patients may become severely ill and be taken into hospital with an infection and/or very high blood sugar levels.
Every cell in the human body needs energy in order to function. The body's primary energy source is glucose, a simple sugar resulting from the digestion of foods containing carbohydrates (sugars and starches). Glucose from the digested food circulates in the blood as a ready energy source for any cells that need it. Insulin is a hormone or chemical produced by cells in the pancreas, an organ located behind the stomach. Insulin bonds to a receptor site on the outside of cell and acts like a key to open a doorway into the cell through which glucose can enter. Some of the glucose can be converted to concentrated energy sources like glycogen or fatty acids and saved for later use. When there is not enough insulin produced or when the doorway no longer recognizes the insulin key, glucose stays in the blood rather entering the cells.
Kidney damage from diabetes is called diabetic nephropathy. The onset of kidney disease and its progression is extremely variable. Initially, diseased small blood vessels in the kidneys cause the leakage of protein in the urine. Later on, the kidneys lose their ability to cleanse and filter blood. The accumulation of toxic waste products in the blood leads to the need for dialysis. Dialysis involves using a machine that serves the function of the kidney by filtering and cleaning the blood. In patients who do not want to undergo chronic dialysis, kidney transplantation can be considered.
Large, population-based studies in China, Finland and USA have recently demonstrated the feasibility of preventing, or delaying, the onset of diabetes in overweight subjects with mild glucose intolerance (IGT). The studies suggest that even moderate reduction in weight and only half an hour of walking each day reduced the incidence of diabetes by more than one half.
Occasionally, a child with hypoglycemic coma may not recover within 10 minutes, despite appropriate therapy. Under no circumstances should further treatment be given, especially intravenous glucose, until the blood glucose level is checked and still found to be subnormal. Overtreatment of hypoglycemia can lead to cerebral edema and death. If coma persists, seek other causes.

Large, population-based studies in China, Finland and USA have recently demonstrated the feasibility of preventing, or delaying, the onset of diabetes in overweight subjects with mild glucose intolerance (IGT). The studies suggest that even moderate reduction in weight and only half an hour of walking each day reduced the incidence of diabetes by more than one half.
Diabetes mellitus is a group of metabolic diseases characterized by high blood sugar (glucose) levels that result from defects in insulin secretion, or its action, or both. Diabetes mellitus, commonly referred to as diabetes (as it will be in this article) was first identified as a disease associated with "sweet urine," and excessive muscle loss in the ancient world. Elevated levels of blood glucose (hyperglycemia) lead to spillage of glucose into the urine, hence the term sweet urine.
These diabetes complications are related to blood vessel diseases and are generally classified into small vessel disease, such as those involving the eyes, kidneys and nerves (microvascular disease), and large vessel disease involving the heart and blood vessels (macrovascular disease). Diabetes accelerates hardening of the arteries (atherosclerosis) of the larger blood vessels, leading to coronary heart disease (angina or heart attack), strokes, and pain in the lower extremities because of lack of blood supply (claudication).
The progression of nephropathy in patients can be significantly slowed by controlling high blood pressure, and by aggressively treating high blood sugar levels. Angiotensin converting enzyme inhibitors (ACE inhibitors) or angiotensin receptor blockers (ARBs) used in treating high blood pressure may also benefit kidney disease in patients with diabetes.
Jump up ^ Sattar N, Preiss D, Murray HM, Welsh P, Buckley BM, de Craen AJ, Seshasai SR, McMurray JJ, Freeman DJ, Jukema JW, Macfarlane PW, Packard CJ, Stott DJ, Westendorp RG, Shepherd J, Davis BR, Pressel SL, Marchioli R, Marfisi RM, Maggioni AP, Tavazzi L, Tognoni G, Kjekshus J, Pedersen TR, Cook TJ, Gotto AM, Clearfield MB, Downs JR, Nakamura H, Ohashi Y, Mizuno K, Ray KK, Ford I (February 2010). "Statins and risk of incident diabetes: a collaborative meta-analysis of randomised statin trials". Lancet. 375 (9716): 735–42. doi:10.1016/S0140-6736(09)61965-6. PMID 20167359.
It is a considerable challenge to obtain the goals of the intensively treated patients in the DCCT with the vast majority of people with diabetes given the more limited health care resources typically available in routine practice. If diabetes control can be improved without significant damage to quality of life, the economic, health, and quality of life savings associated with a reduction in complications in later life will be vast. Although some people who have had poorly controlled diabetes over many years do not develop complications, complications commonly arise after 15–20 years of diabetes and individuals in their 40s or even 30s may develop several complications in rapid succession. However, up until the early 1980s, patients had no way of monitoring their own blood glucose levels at home. Urine glucose monitoring only told them when their blood glucose had exceeded the renal threshold of approximately 10 mmol/L (i.e., was far too high), without being able to discriminate between the too high levels of 7–10 mmol/L or the hypoglycemic levels below 4 mmol/L. Clinics relied on random blood glucose testing and there were no measures of average blood glucose over a longer period. Since the 1980s there have been measures of glycosylated hemoglobin (GHb, HbA1, or HbA1c) which indicate average blood glucose over a six to eight week period and measures of glycosylated protein, fructosamine, which indicates average blood glucose over a two-week period. Blood-glucose meters for patients were first introduced in the early 1980s and the accuracy and convenience of the meters and the reagent strips they use has improved dramatically since early models. By the late 1990s blood-glucose monitoring is part of the daily routine for most people using insulin in developed countries. Blood-glucose monitoring is less often prescribed for tablet- and diet-alone-treated patients, financial reasons probably being allowed to outweigh the educational value of accurate feedback in improving control long term. The reduced risk of hypoglycemia and diabetic ketoacidosis in NIDDM patients not using insulin means that acute crises rarely arise in these patients though their risk of long-term complications is at least as great as in IDDM and might be expected to be reduced if feedback from blood-glucose monitoring were provided.
People with type 1 diabetes and certain people with type 2 diabetes may use carbohydrate counting or the carbohydrate exchange system to match their insulin dose to the carbohydrate content of their meal. "Counting" the amount of carbohydrate in a meal is used to calculate the amount of insulin the person takes before eating. However, the carbohydrate-to-insulin ratio (the amount of insulin taken for each gram of carbohydrate in the meal) varies for each person, and people with diabetes need to work closely with a dietician who has experience in working with people with diabetes to master the technique. Some experts have advised use of the glycemic index (a measure of the impact of an ingested carbohydrate-containing food on the blood glucose level) to delineate between rapid and slowly metabolized carbohydrates, although there is little evidence to support this approach.
In this health topic, we explain the dangers of hyperglycemia, or high blood sugar levels, and diabetes. Hyperglycemia causes many of the warning signs of diabetes listed above. Hyperglycemia may be caused by skipping or forgetting your insulin or diabetes medicine, eating too many grams of carbs for the amount of insulin administered, simply eating too many grams of carbs in general, or from stress or infections.