Long-term complications arise from the damaging effects of prolonged hyperglycemia and other metabolic consequences of insulin deficiency on various tissues. Although long-term complications are rare in childhood, maintaining good control of diabetes is important to prevent complications from developing in later life. [39] The likelihood of developing complications appears to depend on the interaction of factors such as metabolic control, genetic susceptibility, lifestyle (eg, smoking, diet, exercise), pubertal status, and gender. [40, 41] Long-term complications include the following:

With gestational diabetes, risks to the unborn baby are even greater than risks to the mother. Risks to the baby include abnormal weight gain before birth, breathing problems at birth, and higher obesity and diabetes risk later in life. Risks to the mother include needing a cesarean section due to an overly large baby, as well as damage to heart, kidney, nerves, and eye.

Several common medications can impair the body's use of insulin, causing a condition known as secondary diabetes. These medications include treatments for high blood pressure (furosemide, clonidine, and thiazide diuretics), drugs with hormonal activity (oral contraceptives, thyroid hormone, progestins, and glucocorticorids), and the anti-inflammation drug indomethacin. Several drugs that are used to treat mood disorders (such as anxiety and depression) also can impair glucose absorption. These drugs include haloperidol, lithium carbonate, phenothiazines, tricyclic antidepressants, and adrenergic agonists. Other medications that can cause diabetes symptoms include isoniazid, nicotinic acid, cimetidine, and heparin. A 2004 study found that low levels of the essential mineral chromium in the body may be linked to increased risk for diseases associated with insulin resistance.
Studies in type 1 patients have shown that in intensively treated patients, diabetic eye disease decreased by 76%, kidney disease decreased by 54%, and nerve disease decreased by 60%. More recently the EDIC trial has shown that type 1 diabetes is also associated with increased heart disease, similar to type 2 diabetes. However, the price for aggressive blood sugar control is a two to three fold increase in the incidence of abnormally low blood sugar levels (caused by the diabetes medications). For this reason, tight control of diabetes to achieve glucose levels between 70 to120 mg/dl is not recommended for children under 13 years of age, patients with severe recurrent hypoglycemia, patients unaware of their hypoglycemia, and patients with far advanced diabetes complications. To achieve optimal glucose control without an undue risk of abnormally lowering blood sugar levels, patients with type 1 diabetes must monitor their blood glucose at least four times a day and administer insulin at least three times per day. In patients with type 2 diabetes, aggressive blood sugar control has similar beneficial effects on the eyes, kidneys, nerves and blood vessels.
Pre-clinical diabetes refers to the time during which destruction of pancreatic insulin-producing cells is occurring, but symptoms have not yet developed. This period may last for months to years. Normally, 80-90% of the pancreatic beta cells must be destroyed before any symptoms of diabetes develops. During this time, blood tests can identify some immunological markers of pancreatic cell destruction. However, there is currently no known treatment to prevent progression of pre-clinical diabetes to true diabetes mellitus.

In animals, diabetes is most commonly encountered in dogs and cats. Middle-aged animals are most commonly affected. Female dogs are twice as likely to be affected as males, while according to some sources, male cats are also more prone than females. In both species, all breeds may be affected, but some small dog breeds are particularly likely to develop diabetes, such as Miniature Poodles.[123]
People with type 1 diabetes are unable to produce any insulin at all. People with type 2 diabetes still produce insulin, however, the cells in the muscles, liver and fat tissue are inefficient at absorbing the insulin and cannot regulate glucose well. As a result, the body tries to compensate by having the pancreas pump out more insulin. But the pancreas slowly loses the ability to produce enough insulin, and as a result, the cells don’t get the energy they need to function properly.
A growing number of people in the U.S. and throughout the world are overweight and more prone to develop Type 2 diabetes, particularly if they have the genetics for it. "Type 2 diabetes can be caused by genetic inheritance, but by far the obesity epidemic has created massive increases in the occurrence of Type 2 diabetes. This is due to the major insulin resistance that is created by obesity," Gage says.
Weight loss surgery in those who are obese is an effective measure to treat diabetes.[101] Many are able to maintain normal blood sugar levels with little or no medication following surgery[102] and long-term mortality is decreased.[103] There however is some short-term mortality risk of less than 1% from the surgery.[104] The body mass index cutoffs for when surgery is appropriate are not yet clear.[103] It is recommended that this option be considered in those who are unable to get both their weight and blood sugar under control.[105][106]
A chronic metabolic disorder in which the use of carbohydrate is impaired and that of lipid and protein is enhanced. It is caused by an absolute or relative deficiency of insulin and is characterized, in more severe cases, by chronic hyperglycemia, glycosuria, water and electrolyte loss, ketoacidosis, and coma. Long-term complications include neuropathy, retinopathy, nephropathy, generalized degenerative changes in large and small blood vessels, and increased susceptibility to infection.
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When you have diabetes, it’s important to avoid eating many packaged, processed snacks such as cookies, chips, cake, granola bars, and the like, in lieu of fresh, whole foods, like fiber-rich fruits, veggies, and whole grains. (27) Eating foods high in fiber can help keep blood sugar levels steady and fill you up, potentially promoting weight loss and improving insulin sensitivity. (28)
Type 2 diabetes was also previously referred to as non-insulin dependent diabetes mellitus (NIDDM), or adult-onset diabetes mellitus (AODM). In type 2 diabetes, patients can still produce insulin, but do so relatively inadequately for their body's needs, particularly in the face of insulin resistance as discussed above. In many cases this actually means the pancreas produces larger than normal quantities of insulin. A major feature of type 2 diabetes is a lack of sensitivity to insulin by the cells of the body (particularly fat and muscle cells).

Type 2 diabetes is a preventable disease that affects more than 9 percent of the U.S. population, or about 29 million people. According to the Centers for Disease Control and Prevention, more than a quarter — some 8 million people — remain undiagnosed. With complications including nerve damage, kidney damage, poor blood circulation, and even death, it’s important for us all to know the early signs of type 2 diabetes.