The most common cause of acquired blindness in many developed nations, diabetic retinopathy is rare in the prepubertal child or within 5 years of onset of diabetes. The prevalence and severity of retinopathy increase with age and are greatest in patients whose diabetic control is poor.  Prevalence rates seem to be declining, yet an estimated 80% of people with type 1 diabetes mellitus develop retinopathy. 
The notion is understandable. Blood sugar levels are high in diabetes, so a common idea has held that eating sugar somehow triggers the disease process. However, the major diabetes organizations take a different view. The American Diabetes Association1 and Diabetes UK2 have labelled this notion a “myth,” as has the Joslin Diabetes Center,3 which wrote, “Diabetes is not caused by eating too much sugar.” These and other organizations have worked to educate people about the causes of diabetes and the role that foods play in the disease process.
Because type 2 diabetes is linked to high levels of sugar in the blood, it may seem logical to assume that eating too much sugar is the cause of the disease. But of course, it’s not that simple. “This has been around for years, this idea that eating too much sugar causes diabetes — but the truth is, type 2 diabetes is a multifactorial disease with many different types of causes,” says Lynn Grieger, RDN, CDE, a nutrition coach in Prescott, Arizona, and a medical reviewer for Everyday Health. “Type 2 diabetes is really complex.”
If you find that you are a little rusty and could use a refresher course in nutrition or anything else related to diabetes, consider signing up for a diabetes conversation map class. These classes are a good way to re-learn key components of diabetes in a group setting. If you have adequate knowledge and are instead looking for ways to make your life easier, check out some apps, nutrition resources, or fitness trackers that can help you stay moving and cook healthy meals. Keeping up the good work is worth it, as it can help prevent complications.
Can type 2 diabetes be cured? In the early stages of type 2 diabetes, it is possible to manage the diabetes to a level where symptoms go away and A1c reaches a normal level – this effectively “reverses” the progression of type 2 diabetes. According to research from Newcastle University, major weight loss can return insulin secretion to normal in people who had type 2 diabetes for four years or less. Indeed, it is commonly believed that significant weight loss and building muscle mass is the best way to reverse type 2 diabetes progression. However, it is important to note that reversing diabetes progression is not the same as curing type 2 diabetes – people still need to monitor their weight, diet, and exercise to ensure that type 2 diabetes does not progress. For many people who have had type 2 diabetes for a longer time, the damage to the beta cells progresses to the point at which it will never again be possible to make enough insulin to correctly control blood glucose, even with dramatic weight loss. But even in these people, weight loss is likely the best way to reduce the threat of complications.
After eating carbohydrates, the carbs break down into sugar, trigger the pancreas to produce insulin and are then stored in liver and muscles. However, there is a limit to the amount of sugar the liver and muscles can store. The easiest way to understand this is to think of your liver and muscles as small closets without much storage space. If sugar keeps coming in, the closet will quickly fill up.
Before blood glucose levels rise, the body of a person destined for type 2 becomes resistant to insulin, much as bacteria can become resistant to antibiotics. Insulin is the signal for the muscles, fat, and liver to absorb glucose from the blood. As the body becomes resistant to insulin, the beta cells in the pancreas must pump out more of the hormone to compensate. People with beta cells that can't keep up with insulin resistance develop the high blood glucose of type 2 diabetes.
Type 2 diabetes is mainly caused by insulin resistance. This means no matter how much or how little insulin is made, the body can't use it as well as it should. As a result, glucose can't be moved from the blood into cells. Over time, the excess sugar in the blood gradually poisons the pancreas causing it to make less insulin and making it even more difficult to keep blood glucose under control.
Several other signs and symptoms can mark the onset of diabetes although they are not specific to the disease. In addition to the known ones above, they include blurred vision, headache, fatigue, slow healing of cuts, and itchy skin. Prolonged high blood glucose can cause glucose absorption in the lens of the eye, which leads to changes in its shape, resulting in vision changes. Long-term vision loss can also be caused by diabetic retinopathy. A number of skin rashes that can occur in diabetes are collectively known as diabetic dermadromes.
In type 1 diabetes (formerly called insulin-dependent diabetes or juvenile-onset diabetes), the body's immune system attacks the insulin-producing cells of the pancreas, and more than 90% of them are permanently destroyed. The pancreas, therefore, produces little or no insulin. Only about 5 to 10% of all people with diabetes have type 1 disease. Most people who have type 1 diabetes develop the disease before age 30, although it can develop later in life.
When diabetes occurs in women during pregnancy, it is called gestational diabetes. It usually is diagnosed between the 24th and 28th weeks of pregnancy. Like in type 1 and type 2 diabetes, blood sugar levels become too high. When women are pregnant, more glucose is needed to nourish the developing baby. The body needs more insulin, which is produced by the pancreas. In some women, the body does not produce enough insulin to meet this need, and blood sugar levels rise, resulting in gestational diabetes.
The ADA recommends using patient age as one consideration in the establishment of glycemic goals, with different targets for preprandial, bedtime/overnight, and hemoglobin A1c (HbA1c) levels in patients aged 0-6, 6-12, and 13-19 years.  Benefits of tight glycemic control include not only continued reductions in the rates of microvascular complications but also significant differences in cardiovascular events and overall mortality.
Hypoglycemia means abnormally low blood sugar (glucose). In patients with diabetes, the most common cause of low blood sugar is excessive use of insulin or other glucose-lowering medications, to lower the blood sugar level in diabetic patients in the presence of a delayed or absent meal. When low blood sugar levels occur because of too much insulin, it is called an insulin reaction. Sometimes, low blood sugar can be the result of an insufficient caloric intake or sudden excessive physical exertion.
ORAL GLUCOSE TOLERANCE TEST. Blood samples are taken from a vein before and after a patient drinks a thick, sweet syrup of glucose and other sugars. In a non-diabetic, the level of glucose in the blood goes up immediately after the drink and then decreases gradually as insulin is used by the body to metabolize, or absorb, the sugar. In a diabetic, the glucose in the blood goes up and stays high after drinking the sweetened liquid. A plasma glucose level of 11.1 mmol/L (200 mg/dL) or higher at two hours after drinking the syrup and at one other point during the two-hour test period confirms the diagnosis of diabetes.
Type 2 diabetes occurs when the pancreas does not make enough insulin or the body does not use insulin properly. It usually occurs in adults, although in some cases children may be affected. People with type 2 diabetes usually have a family history of this condition and 90% are overweight or obese. People with type 2 diabetes may eventually need insulin injections. This condition occurs most commonly in people of Indigenous and African descent, Hispanics, and Asians.
Low blood sugar (hypoglycemia), is common in people with type 1 and type 2 DM. Most cases are mild and are not considered medical emergencies. Effects can range from feelings of unease, sweating, trembling, and increased appetite in mild cases to more serious effects such as confusion, changes in behavior such as aggressiveness, seizures, unconsciousness, and (rarely) permanent brain damage or death in severe cases. Moderately low blood sugar may easily be mistaken for drunkenness; rapid breathing and sweating, cold, pale skin are characteristic of low blood sugar but not definitive. Mild to moderate cases are self-treated by eating or drinking something high in sugar. Severe cases can lead to unconsciousness and must be treated with intravenous glucose or injections with glucagon.
"We know that there is a very large genetic component," Rettinger says. "A person with a first-degree relative with Type 2 diabetes has a five to 10 time higher risk of developing diabetes than a person the same age and weight without a family history of Type 2 diabetes." Heredity actually plays a larger role in Type 2 diabetes than Type 1, Rettinger says.
Impaired glucose tolerance (IGT) and impaired fasting glycaemia (IFG) refer to levels of blood glucose concentration above the normal range, but below those which are diagnostic for diabetes. Subjects with IGT and/or IFG are at substantially higher risk of developing diabetes and cardiovascular disease than those with normal glucose tolerance. The benefits of clinical intervention in subjects with moderate glucose intolerance is a topic of much current interest.