Type 2 diabetes used to be called adult-onset diabetes or non-insulin dependent diabetes because it was diagnosed mainly in adults who did not require insulin to manage their condition. However, because more children are starting to be diagnosed with T2D, and insulin is used more frequently to help manage type 2 diabetes, referring to the condition as “adult-onset” or “non-insulin dependent” is no longer accurate.

Janis McWilliams, RN, MSN, CDE, BC-ADM, responds: Yes, in type 1 diabetes in particular, the onset of symptoms like frequent urination and extreme thirst can be very sudden. In type 2 diabetes, the symptoms tend to come about more gradually, and sometimes there are no signs at all. People who have symptoms should contact their health care provider immediately for an accurate diagnosis. Keep in mind that these symptoms could signal other problems, too.

In patients with type 2 diabetes, stress, infection, and medications (such as corticosteroids) can also lead to severely elevated blood sugar levels. Accompanied by dehydration, severe blood sugar elevation in patients with type 2 diabetes can lead to an increase in blood osmolality (hyperosmolar state). This condition can worsen and lead to coma (hyperosmolar coma). A hyperosmolar coma usually occurs in elderly patients with type 2 diabetes. Like diabetic ketoacidosis, a hyperosmolar coma is a medical emergency. Immediate treatment with intravenous fluid and insulin is important in reversing the hyperosmolar state. Unlike patients with type 1 diabetes, patients with type 2 diabetes do not generally develop ketoacidosis solely on the basis of their diabetes. Since in general, type 2 diabetes occurs in an older population, concomitant medical conditions are more likely to be present, and these patients may actually be sicker overall. The complication and death rates from hyperosmolar coma is thus higher than in diabetic ketoacidosis.

A final note about type 1: Some people have a "honeymoon" period, a brief remission of symptoms while the pancreas is still secreting some insulin. The honeymoon phase typically occurs after insulin treatment has been started. A honeymoon can last as little as a week or even up to a year. But the absence of symptoms doesn't mean the diabetes is gone. The pancreas will eventually be unable to secrete insulin, and, if untreated, the symptoms will return.

Merck & Co., Inc., Kenilworth, NJ, USA is a global healthcare leader working to help the world be well. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world. The Merck Manual was first published in 1899 as a service to the community. The legacy of this great resource continues as the Merck Manual in the US and Canada and the MSD Manual outside of North America. Learn more about our commitment to Global Medical Knowledge.
Ketoacidosis, a condition due to starvation or uncontrolled diabetes, is common in Type I diabetes. Ketones are acid compounds that form in the blood when the body breaks down fats and proteins. Symptoms include abdominal pain, vomiting, rapid breathing, extreme lethargy, and drowsiness. Patients with ketoacidosis will also have a sweet breath odor. Left untreated, this condition can lead to coma and death.
How does type 2 diabetes progress over time? Type 2 diabetes is a progressive disease, meaning that the body’s ability to regulate blood sugar gets worse over time, despite careful management. Over time, the body’s cells become increasingly less responsive to insulin (increased insulin resistance) and beta cells in the pancreas produce less and less insulin (called beta-cell burnout). In fact, when people are diagnosed with type 2 diabetes, they usually have already lost up to 50% or more of their beta cell function. As type 2 diabetes progresses, people typically need to add one or more different types of medications. The good news is that there are many more choices available for treatments, and a number of these medications don’t cause as much hypoglycemia, hunger and/or weight gain (e.g., metformin, pioglitazone, DPP-4 inhibitors, GLP-1 agonists, SGLT-2 inhibitors, and better insulin). Diligent management early on can help preserve remaining beta cell function and sometimes slow progression of the disease, although the need to use more and different types of medications does not mean that you have failed.
The United Kingdom Prospective Diabetes Study (UKPDS) was a clinical study conducted by Z that was published in The Lancet in 1998. Around 3,800 people with type 2 diabetes were followed for an average of ten years, and were treated with tight glucose control or the standard of care, and again the treatment arm had far better outcomes. This confirmed the importance of tight glucose control, as well as blood pressure control, for people with this condition.[86][132][133]
Type 2 diabetes, the most common type of diabetes, is a disease that occurs when your blood glucose, also called blood sugar, is too high. Blood glucose is your main source of energy and comes mainly from the food you eat. Insulin, a hormone made by the pancreas, helps glucose get into your cells to be used for energy. In type 2 diabetes, your body doesn’t make enough insulin or doesn’t use insulin well. Too much glucose then stays in your blood, and not enough reaches your cells.
Threshold for diagnosis of diabetes is based on the relationship between results of glucose tolerance tests, fasting glucose or HbA1c and complications such as retinal problems.[10] A fasting or random blood sugar is preferred over the glucose tolerance test, as they are more convenient for people.[10] HbA1c has the advantages that fasting is not required and results are more stable but has the disadvantage that the test is more costly than measurement of blood glucose.[50] It is estimated that 20% of people with diabetes in the United States do not realize that they have the disease.[10]
The problem with sweetened drinks is that, due to their liquid form, they’re among the fastest simple carbs to be digested in the body, causing blood sugar levels to spike even more than a simple carb in solid-food form would. Research supports this idea: A review published in November 2010 in the journal Diabetes Care suggested adding only one serving of a sweetened beverage to your diet may increase your risk for type 2 diabetes by 15 percent.
Triglycerides are a common form of fat that we digest. Triglycerides are the main ingredient in animal fats and vegetable oils. Elevated levels of triglycerides are a risk factor for heart disease, heart attack, stroke, fatty liver disease, and pancreatitis. Elevated levels of triglycerides are also associated with diseases like diabetes, kidney disease, and medications (for example, diuretics, birth control pills, and beta blockers). Dietary changes, and medication if necessary can help lower triglyceride blood levels.
The body obtains glucose from three main sources: the intestinal absorption of food; the breakdown of glycogen (glycogenolysis), the storage form of glucose found in the liver; and gluconeogenesis, the generation of glucose from non-carbohydrate substrates in the body.[60] Insulin plays a critical role in balancing glucose levels in the body. Insulin can inhibit the breakdown of glycogen or the process of gluconeogenesis, it can stimulate the transport of glucose into fat and muscle cells, and it can stimulate the storage of glucose in the form of glycogen.[60]

Because people with type 2 diabetes produce some insulin, ketoacidosis does not usually develop even when type 2 diabetes is untreated for a long time. Rarely, the blood glucose levels become extremely high (even exceeding 1,000 mg/dL). Such high levels often happen as the result of some superimposed stress, such as an infection or drug use. When the blood glucose levels get very high, people may develop severe dehydration, which may lead to mental confusion, drowsiness, and seizures, a condition called hyperosmolar hyperglycemic state. Currently, many people with type 2 diabetes are diagnosed by routine blood glucose testing before they develop such severely high blood glucose levels.
Also striking are the differences in incidence between mainland Italy (8.4 cases per 100,000 population) and the Island of Sardinia (36.9 cases per 100,000 population). These variations strongly support the importance of environmental factors in the development of type 1 diabetes mellitus. Most countries report that incidence rates have at least doubled in the last 20 years. Incidence appears to increase with distance from the equator. [31]
Diabetes mellitus is a metabolic condition in which a person's blood sugar (glucose) levels are too high. Over 29.1 million children and adults in the US have diabetes. Of that, 8.1 million people have diabetes and don't even know it. Type 1 diabetes (insulin-dependent, juvenile) is caused by a problem with insulin production by the pancreas. Type 2 diabetes (non-insulin dependent) is caused by:
We give you special kudos for managing your condition, as it is not always easy. If you've had diabetes for a long time, it's normal to burn out sometimes. You may get tired of your day to day tasks, such as counting carbohydrates or measuring your blood sugar. Lean on a loved one or a friend for support, or consider talking to someone else who has diabetes who can provide, perhaps, an even more understanding ear or ideas that can help you.
Management of type 2 diabetes focuses on lifestyle interventions, lowering other cardiovascular risk factors, and maintaining blood glucose levels in the normal range.[24] Self-monitoring of blood glucose for people with newly diagnosed type 2 diabetes may be used in combination with education,[70] however the benefit of self monitoring in those not using multi-dose insulin is questionable.[24][71] In those who do not want to measure blood levels, measuring urine levels may be done.[70] Managing other cardiovascular risk factors, such as hypertension, high cholesterol, and microalbuminuria, improves a person's life expectancy.[24] Decreasing the systolic blood pressure to less than 140 mmHg is associated with a lower risk of death and better outcomes.[72] Intensive blood pressure management (less than 130/80 mmHg) as opposed to standard blood pressure management (less than 140-160 mmHg systolic to 85–100 mmHg diastolic) results in a slight decrease in stroke risk but no effect on overall risk of death.[73]

The definition of a genetic disease is a disorder or condition caused by abnormalities in a person's genome. Some types of genetic inheritance include single inheritance, including cystic fibrosis, sickle cell anemia, Marfan syndrome, and hemochromatosis. Other types of genetic diseases include multifactorial inheritance. Still other types of genetic diseases include chromosome abnormalities (for example, Turner syndrome, and Klinefelter syndrome), and mitochondrial inheritance (for example, epilepsy and dementia).

It is recommended that all people with type 2 diabetes get regular eye examination.[13] There is weak evidence suggesting that treating gum disease by scaling and root planing may result in a small short-term improvement in blood sugar levels for people with diabetes.[79] There is no evidence to suggest that this improvement in blood sugar levels is maintained longer than 4 months.[79] There is also not enough evidence to determine if medications to treat gum disease are effective at lowering blood sugar levels.[79]
Pay attention if you find yourself feeling drowsy or lethargic; pain or numbness in your extremities; vision changes; fruity or sweet-smelling breath which is one of the symptoms of high ketones; and experiencing nausea or vomiting—as these are additional signs that something is not right. If there’s any question, see your doctor immediately to ensure that your blood sugar levels are safe and rule out diabetes.
George P Chrousos, MD, FAAP, MACP, MACE, FRCP(London) is a member of the following medical societies: American Academy of Pediatrics, American College of Physicians, American Pediatric Society, American Society for Clinical Investigation, Association of American Physicians, Endocrine Society, Pediatric Endocrine Society, Society for Pediatric Research, American College of Endocrinology
Although some people with this type of diabetes are thin, the majority of people (90%) are overweight. Losing weight, even 2 kg to 5 kg (5 lbs to 10 lbs) can help lower blood glucose levels. For many people, following a healthy diet and an exercise program may be all that is needed to help control glucose levels. For others, healthy eating and exercise alone aren't enough to lower blood glucose levels.
Onset of type 2 diabetes can be delayed or prevented through proper nutrition and regular exercise.[60][61] Intensive lifestyle measures may reduce the risk by over half.[24][62] The benefit of exercise occurs regardless of the person's initial weight or subsequent weight loss.[63] High levels of physical activity reduce the risk of diabetes by about 28%.[64] Evidence for the benefit of dietary changes alone, however, is limited,[65] with some evidence for a diet high in green leafy vegetables[66] and some for limiting the intake of sugary drinks.[32] In those with impaired glucose tolerance, diet and exercise either alone or in combination with metformin or acarbose may decrease the risk of developing diabetes.[24][67] Lifestyle interventions are more effective than metformin.[24] A 2017 review found that, long term, lifestyle changes decreased the risk by 28%, while medication does not reduce risk after withdrawal.[68] While low vitamin D levels are associated with an increased risk of diabetes, correcting the levels by supplementing vitamin D3 does not improve that risk.[69]
Treatment of pituitary diabetes insipidus consists of administration of vasopressin. A synthetic analogue of vasopressin (DDAVP) can be administered as a nasal spray, providing antidiuretic activity for 8 to 20 hours, and is currently the drug of choice. Patient care includes instruction in self-administration of the drug, its expected action, symptoms that indicate a need to adjust the dosage, and the importance of follow-up visits. Patients with this condition should wear some form of medical identification at all times.
Creatinine is a chemical waste molecule that is generated from muscle metabolism. Creatinine is produced from creatine, a molecule of major importance for energy production in muscles. Creatinine has been found to be a fairly reliable indicator of kidney function. As the kidneys become impaired the creatinine level in the blood will rise. Normal levels of creatinine in the blood vary from gender and age of the individual.
There are a number of medications and other health problems that can predispose to diabetes.[39] Some of the medications include: glucocorticoids, thiazides, beta blockers, atypical antipsychotics,[40] and statins.[41] Those who have previously had gestational diabetes are at a higher risk of developing type 2 diabetes.[23] Other health problems that are associated include: acromegaly, Cushing's syndrome, hyperthyroidism, pheochromocytoma, and certain cancers such as glucagonomas.[39] Testosterone deficiency is also associated with type 2 diabetes.[42][43]
Type 2 diabetes is partly preventable by staying a normal weight, exercising regularly, and eating properly.[1] Treatment involves exercise and dietary changes.[1] If blood sugar levels are not adequately lowered, the medication metformin is typically recommended.[7][14] Many people may eventually also require insulin injections.[9] In those on insulin, routinely checking blood sugar levels is advised; however, this may not be needed in those taking pills.[15] Bariatric surgery often improves diabetes in those who are obese.[8][16]
Constant advances are being made in development of new oral medications for persons with diabetes. In 2003, a drug called Metaglip combining glipizide and metformin was approved in a dingle tablet. Along with diet and exercise, the drug was used as initial therapy for Type 2 diabetes. Another drug approved by the U.S. Food and Drug Administration (FDA) combines metformin and rosiglitazone (Avandia), a medication that increases muscle cells' sensitivity to insulin. It is marketed under the name Avandamet. So many new drugs are under development that it is best to stay in touch with a physician for the latest information; physicians can find the best drug, diet and exercise program to fit an individual patient's need.
Does having type 2 diabetes affect life expectancy? While continued improvements in therapies and care for type 2 diabetes may be helping patients live longer, the unfortunate reality is that type 2 diabetes has been shown to decrease life expectancy by up to ten years, according to Diabetes UK. There is still much to be done to ensure that all patients have access to appropriate healthcare and treatments to live a happier and healthier life with type 2 diabetes.
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)
Sequelae. The long-term consequences of diabetes mellitus can involve both large and small blood vessels throughout the body. That in large vessels is usually seen in the coronary arteries, cerebral arteries, and arteries of the lower extremities and can eventually lead to myocardial infarction, stroke, or gangrene of the feet and legs. atherosclerosis is far more likely to occur in persons of any age who have diabetes than it is in other people. This predisposition is not clearly understood. Some believe that diabetics inherit the tendency to develop severe atherosclerosis as well as an aberration in glucose metabolism, and that the two are not necessarily related. There is strong evidence to substantiate the claim that optimal control will mitigate the effects of diabetes on the microvasculature, particularly in the young and middle-aged who are at greatest risk for developing complications involving the arterioles. Pathologic changes in the small blood vessels serving the kidney lead to nephrosclerosis, pyelonephritis, and other disorders that eventually result in renal failure. Many of the deaths of persons with type 1 diabetes are caused by renal failure.
Fasting glucose test This test involves giving a blood sample after you have fasted for eight hours. (18) If you have a fasting blood sugar level of less than 100 milligrams per deciliter (mg/dl), your blood sugar levels are normal. But if you have one from 100 to 125 mg/dl, you have prediabetes, and if you have 126 mg/dl on two separate occasions, you have diabetes. (17)

It has become fashionable in recent years to blame sugar for many health problems. However, per capita sugar consumption has actually been falling in the United States since 1999, when bottled water and sugar-free beverages began to edge sodas off the shelf. At the same time, consumption of cheese and oily foods has steadily increased, as has diabetes prevalence. This suggests that something other than sugar is driving the diabetes epidemic. 

People usually develop type 2 diabetes after the age of 40 years, although people of South Asian origin are at an increased risk of the condition and may develop diabetes from the age of 25 onwards. The condition is also becoming increasingly common among children and adolescents across all populations. Type 2 diabetes often develops as a result of overweight, obesity and lack of physical activity and diabetes prevalence is on the rise worldwide as these problems become more widespread.
People with full-blown type 2 diabetes are not able to use the hormone insulin properly, and have what’s called insulin resistance. Insulin is necessary for glucose, or sugar, to get from your blood into your cells to be used for energy. When there is not enough insulin — or when the hormone doesn’t function as it should — glucose accumulates in the blood instead of being used by the cells. This sugar accumulation may lead to the aforementioned complications.