Diabetes mellitus is classified into four broad categories: type 1, type 2, gestational diabetes, and "other specific types".[11] The "other specific types" are a collection of a few dozen individual causes.[11] Diabetes is a more variable disease than once thought and people may have combinations of forms.[37] The term "diabetes", without qualification, usually refers to diabetes mellitus.

Maturity onset diabetes of the young (MODY) is a rare autosomal dominant inherited form of diabetes, due to one of several single-gene mutations causing defects in insulin production.[52] It is significantly less common than the three main types. The name of this disease refers to early hypotheses as to its nature. Being due to a defective gene, this disease varies in age at presentation and in severity according to the specific gene defect; thus there are at least 13 subtypes of MODY. People with MODY often can control it without using insulin.
Is type 2 diabetes serious? Type 2 diabetes is not a death sentence, but it is a very serious disease that demands attention and careful monitoring. There is no such thing as ‘mild’ diabetes. Elevated glucose levels can damage the nervous system, blood vessels, eyes, heart, and kidneys. These complications really impact quality of life (through blindness, amputations, dialysis etc). They also significantly increase the chance of a stroke or heart attack. Managing blood glucose levels immediately, along with other health risk factors (e.g., cholesterol, blood pressure, weight), is necessary for preventing these complications. Losing even a small amount of weight and keeping it off can also improve glucose control as well as have other clinical benefits (read more tips on managing diet and exercise below for more on weight loss). Keep in mind that better diabetes management also has benefits in the here and now – mood and energy levels are adversely affected when your glucose levels are high. 
Patients who suffer from diabetes have a lifelong struggle to attain and maintain blood glucose levels as close to the normal range as possible. With appropriate blood sugar control, the risk of both microvascular (small blood vessel) and neuropathic (nerve) complications is decreased markedly. Additionally, if hypertension (high blood pressure) and hyperlipidemia (high cholesterol) are treated promptly and aggressively, the risk of cardiovascular complications should decrease as well.
All types of diabetes mellitus have something in common. Normally, your body breaks down the sugars and carbohydrates you eat into a special sugar called glucose. Glucose fuels the cells in your body. But the cells need insulin, a hormone, in your bloodstream in order to take in the glucose and use it for energy. With diabetes mellitus, either your body doesn't make enough insulin, it can't use the insulin it does produce, or a combination of both.
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.
Dr. Balentine received his undergraduate degree from McDaniel College in Westminster, Maryland. He attended medical school at the Philadelphia College of Osteopathic Medicine graduating in1983. He completed his internship at St. Joseph's Hospital in Philadelphia and his Emergency Medicine residency at Lincoln Medical and Mental Health Center in the Bronx, where he served as chief resident.
diabetes mel´litus a broadly applied term used to denote a complex group of syndromes that have in common a disturbance in the oxidation and utilization of glucose, which may be secondary to a malfunction of the beta cells of the pancreas, whose function is the production and release of insulin. Because insulin is involved in the metabolism of carbohydrates, proteins, and fats, diabetes is not limited to a disturbance of glucose homeostasis alone. Insulin resistance may also sometimes play a role in the etiology of diabetes. 
Healthy lifestyle choices can help you prevent type 2 diabetes. Even if you have diabetes in your family, diet and exercise can help you prevent the disease. If you've already received a diagnosis of diabetes, you can use healthy lifestyle choices to help prevent complications. And if you have prediabetes, lifestyle changes can slow or halt the progression from prediabetes to diabetes.
Diabetes can be hard enough as it is, so do what you can to make life with it less complicated. For example, you don't have to be a master chef to put together a healthy meal. You can use ingredients that are right in your home. If you find your medication regimen to be too complex or too expensive, request that your physician change it. If you continue to forget to take your medicines, find simple ways to help you take them, like setting a reminder on your cell phone.
Home blood glucose monitoring kits are available so patients with diabetes can monitor their own levels. A small needle or lancet is used to prick the finger and a drop of blood is collected and analyzed by a monitoring device. Some patients may test their blood glucose levels several times during a day and use this information to adjust their doses of insulin.
Monogenic diabetes is caused by mutations, or changes, in a single gene. These changes are usually passed through families, but sometimes the gene mutation happens on its own. Most of these gene mutations cause diabetes by making the pancreas less able to make insulin. The most common types of monogenic diabetes are neonatal diabetes and maturity-onset diabetes of the young (MODY). Neonatal diabetes occurs in the first 6 months of life. Doctors usually diagnose MODY during adolescence or early adulthood, but sometimes the disease is not diagnosed until later in life.
Normally, blood glucose levels are tightly controlled by insulin, a hormone produced by the pancreas. Insulin lowers the blood glucose level. When the blood glucose elevates (for example, after eating food), insulin is released from the pancreas to normalize the glucose level by promoting the uptake of glucose into body cells. In patients with diabetes, the absence of insufficient production of or lack of response to insulin causes hyperglycemia. Diabetes is a chronic medical condition, meaning that although it can be controlled, it lasts a lifetime.
If you are symptomatic (e.g., increased thirst or urination, unexplained weight loss), your doctor may only use a single test to diagnose diabetes/prediabetes. If you don't have any symptoms, one high blood glucose test doesn't necessarily mean you have diabetes/prediabetes. Your doctor will repeat one of the blood tests again on another day (generally 1 week later) to confirm the diagnosis.
Diabetes mellitus is a condition in which the pancreas no longer produces enough insulin or cells stop responding to the insulin that is produced, so that glucose in the blood cannot be absorbed into the cells of the body. Symptoms include frequent urination, lethargy, excessive thirst, and hunger. The treatment includes changes in diet, oral medications, and in some cases, daily injections of insulin.
Blood travels throughout your body, and when too much glucose (sugar) is present, it disrupts the normal environment that the organ systems of your body function within. In turn, your body starts to exhibit signs that things are not working properly inside—those are the symptoms of diabetes people sometimes experience. If this problem—caused by a variety of factors—is left untreated, it can lead to a number of damaging complications such as heart attacks, strokes, blindness, kidney failure, and blood vessel disease that may require an amputation, nerve damage, and impotence in men.
It is also important to note that currently one third of those who have IGT are in the productive age between 20-39 yr and, therefore, are likely to spend many years at high risk of developing diabetes and/or complications of diabetes1. Some persons with prediabetes experience reactive hypoglycaemia 2-3 hours after a meal. This is a sign of impaired insulin metabolism indicative of impending occurrence of diabetes. Therefore, periodic medical check-up in people with such signs or risk factors for diabetes would reduce the hazards involved in having undiagnosed diabetes. It would help improve the health status of a large number of people who otherwise would be silent sufferers from the metabolic aberrations associated with diabetes.
People with diabetes can benefit from education about the disease and treatment, good nutrition to achieve a normal body weight, and exercise, with the goal of keeping both short-term and long-term blood glucose levels within acceptable bounds. In addition, given the associated higher risks of cardiovascular disease, lifestyle modifications are recommended to control blood pressure.[80][81]
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]
Knowledge is power. A certified diabetes educator can provide you with diabetes self-management education. They specialize in diabetes and can help you learn about complicated or easier things. For example, they can help you set up your glucose meter, teach you about how your medicines work, or help you put together a meal plan. You can meet with them one on one or in group setting.
The classic presenting symptoms of type 1 diabetes mellitus are discussed below. For some children, the first symptoms of diabetes mellitus are those of diabetic ketoacidosis. This is a serious and life-threatening condition, requiring immediate treatment. Ketoacidosis occurs due to a severe disturbance in the body’s metabolism. Without insulin, glucose cannot be taken up into cells. Instead fats are broken down for energy which can have acid by-products.  

Type 2 diabetes is often treated with oral medication because many people with this type of diabetes make some insulin on their own. The pills people take to control type 2 diabetes do not contain insulin. Instead, medications such as metformin, sulfonylureas, alpha-glucosidase inhibitors and many others are used to make the insulin that the body still produces more effective.

A: There are two scenarios to consider here, pregnant patients who have diabetes and pregnant patients who have gestational diabetes. Gestational diabetes describes hyperglycemia discovered during pregnancy. This hyperglycemia often corrects itself after pregnancy, but women who experience gestational diabetes are at higher for developing type-2 diabetes later in life when compared to women who experience no hyperglycemia during pregnancy. Regardless of the type of diabetes a pregnant patient has, her physician will closely monitor her disease and its response to therapy. Proper glucose control is important not only for the health of the mother, but also her developing child.

Jump up ^ O'Gara PT, Kushner FG, Ascheim DD, Casey DE, Chung MK, de Lemos JA, Ettinger SM, Fang JC, Fesmire FM, Franklin BA, Granger CB, Krumholz HM, Linderbaum JA, Morrow DA, Newby LK, Ornato JP, Ou N, Radford MJ, Tamis-Holland JE, Tommaso CL, Tracy CM, Woo YJ, Zhao DX, Anderson JL, Jacobs AK, Halperin JL, Albert NM, Brindis RG, Creager MA, DeMets D, Guyton RA, Hochman JS, Kovacs RJ, Kushner FG, Ohman EM, Stevenson WG, Yancy CW (January 2013). "2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines". Circulation. 127 (4): e362–425. doi:10.1161/CIR.0b013e3182742cf6. PMID 23247304.

The diabetic patient should learn to recognize symptoms of low blood sugar (such as confusion, sweats, and palpitations) and high blood sugar (such as, polyuria and polydipsia). When either condition results in hospitalization, vital signs, weight, fluid intake, urine output, and caloric intake are accurately documented. Serum glucose and urine ketone levels are evaluated. Chronic management of DM is also based on periodic measurement of glycosylated hemoglobin levels (HbA1c). Elevated levels of HbA1c suggest poor long-term glucose control. The effects of diabetes on other body systems (such as cerebrovascular, coronary artery, and peripheral vascular) should be regularly assessed. Patients should be evaluated regularly for retinal disease and visual impairment and peripheral and autonomic nervous system abnormalities, e.g., loss of sensation in the feet. The patient is observed for signs and symptoms of diabetic neuropathy, e.g., numbness or pain in the hands and feet, decreased vibratory sense, footdrop, and neurogenic bladder. The urine is checked for microalbumin or overt protein losses, an early indication of nephropathy. The combination of peripheral neuropathy and peripheral arterial disease results in changes in the skin and microvasculature that lead to ulcer formation on the feet and lower legs with poor healing. Approx. 45,000 lower-extremity diabetic amputations are performed in the U.S. each year. Many amputees have a second amputation within five years. Most of these amputations are preventable with regular foot care and examinations. Diabetic patients and their providers should look for changes in sensation to touch and vibration, the integrity of pulses, capillary refill, and the skin. All injuries, cuts, and blisters should be treated promptly. The patient should avoid constricting hose, slippers, shoes, and bed linens or walking barefoot. The patient with ulcerated or insensitive feet is referred to a podiatrist for continuing foot care and is warned that decreased sensation can mask injuries.
Type 2 (formerly called 'adult-onset' or 'non insulin-dependent') diabetes results when the body doesn’t produce enough insulin and/or is unable to use insulin properly (this is also referred to as ‘insulin resistance’). This form of diabetes usually occurs in people who are over 40 years of age, overweight, and have a family history of diabetes, although today it is increasingly found in younger people.

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.
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]
In an otherwise healthy individual, blood glucose levels usually do not rise above 180 mg/dL (9 mmol/L). In a child with diabetes, blood sugar levels rise if insulin is insufficient for a given glucose load. The renal threshold for glucose reabsorption is exceeded when blood glucose levels exceed 180 mg/dL (10 mmol/L), causing glycosuria with the typical symptoms of polyuria and polydipsia. (See Pathophysiology, Clinical, and Treatment.)
Recognizing the symptoms of Type 1 diabetes is critical. Although Type 1 develops gradually, as the body’s insulin production decreases, blood glucose levels can become dangerously high once insulin production is outpaced. Symptoms may develop rapidly and can be mistaken for other illnesses such as the flu and a delayed diagnosis can have serious consequences.
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]
The term "diabetes" or "to pass through" was first used in 230 BCE by the Greek Apollonius of Memphis.[108] The disease was considered rare during the time of the Roman empire, with Galen commenting he had only seen two cases during his career.[108] This is possibly due to the diet and lifestyle of the ancients, or because the clinical symptoms were observed during the advanced stage of the disease. Galen named the disease "diarrhea of the urine" (diarrhea urinosa).[110]

Oral Agents. Oral antidiabetic drugs (see hypoglycemic agents) are sometimes prescribed for patients with type 2 diabetes who cannot control their blood glucose with diet and exercise. These are not oral forms of insulin; they are sulfonylureas, chemically related to the sulfonamide antibiotics. Patients receiving them should be taught that the drug they are taking does not eliminate the need for a diet and exercise program. Only the prescribed dosage should be taken; it should never be increased to make up for dietary indiscretions or discontinued unless authorized by the physician.
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.
Those dark patches on your skin could be more serious than a blotchy tan. In fact, they might be the first sign of diabetes. This darkening of the skin, which usually occurs on the hands and feet, in folds of skin, along the neck, and in a person’s groin and armpits, called acanthosis nigricans, often occurs when insulin levels are high. The high insulin levels in your blood can increase your body’s production of skin cells, many of which have increased pigmentation, giving skin a darkened appearance.
The blood vessels and blood are the highways that transport sugar from where it is either taken in (the stomach) or manufactured (in the liver) to the cells where it is used (muscles) or where it is stored (fat). Sugar cannot go into the cells by itself. The pancreas releases insulin into the blood, which serves as the helper, or the "key," that lets sugar into the cells for use as energy.

Type 2 diabetes typically starts with insulin resistance. That is, the cells of the body resist insulin’s efforts to escort glucose into the cells. What causes insulin resistance? It appears to be caused by an accumulation of microscopic fat particles within muscle and liver cells.4 This fat comes mainly from the diet—chicken fat, beef fat, cheese fat, fish fat, and even vegetable fat. To try to overcome insulin resistance, the pancreas produces extra insulin. When the pancreas can no longer keep up, blood sugar rises. The combination of insulin resistance and pancreatic cell failure leads to type 2 diabetes.
5. Signs and symptoms ofhyperglycemiaandhypoglycemia, and measures to take when they occur. (See accompanying table.) It is important for patients to become familiar with specific signs that are unique to themselves. Each person responds differently and may exhibit symptoms different from those experienced by others. It should be noted that the signs and symptoms may vary even within one individual. Thus it is vital that the person understand all reactions that could occur. When there is doubt, a simple blood glucose reading will determine the actions that should be taken.
How to use basal insulin: Benefits, types, and dosage Basal, or background, insulin helps regulate blood sugar levels in people diagnosed with diabetes. It keeps glucose levels steady throughout the day and night. It is taken as injections, once a day or more often. The type of insulin and number of daily injections varies. Find out more about the options available. Read now
This depends on the type of diabetes. Type 2 diabetes, and to a lesser extent type 1 diabetes, may run in families. If a parent has diabetes, their children will not necessarily get it but they are at an increased risk. In type 2 diabetes, lifestyle factors such as being overweight (obesity) and lack of exercise can significantly increase your risk of developing diabetes. Some rarer types of diabetes mellitus may be inherited.
Some people with type 2 diabetes are treated with insulin. Insulin is either injected with a syringe several times per day, or delivered via an insulin pump. The goal of insulin therapy is to mimic the way the pancreas would produce and distribute its own insulin, if it were able to manufacture it. Taking insulin does not mean you have done a bad job of trying to control your blood glucose—instead it simply means that your body doesn’t produce or use enough of it on its own to cover the foods you eat.

The word diabetes (/ˌdaɪ.əˈbiːtiːz/ or /ˌdaɪ.əˈbiːtɪs/) comes from Latin diabētēs, which in turn comes from Ancient Greek διαβήτης (diabētēs), which literally means "a passer through; a siphon".[111] Ancient Greek physician Aretaeus of Cappadocia (fl. 1st century CE) used that word, with the intended meaning "excessive discharge of urine", as the name for the disease.[112][113] Ultimately, the word comes from Greek διαβαίνειν (diabainein), meaning "to pass through,"[111] which is composed of δια- (dia-), meaning "through" and βαίνειν (bainein), meaning "to go".[112] The word "diabetes" is first recorded in English, in the form diabete, in a medical text written around 1425.
A study by Dabelea et al found that in teenagers and young adults in whom diabetes mellitus had been diagnosed during childhood or adolescence, diabetes-related complications and comorbidities—including diabetic kidney disease, retinopathy, and peripheral neuropathy (but not arterial stiffness or hypertension)—were more prevalent in those with type 2 diabetes than in those with type 1 disease. [44]

Skin care: High blood glucose and poor circulation can lead to skin problems such as slow healing after an injury or frequent infections. Make sure to wash every day with a mild soap and warm water, protect your skin by using sunscreen, take good care of any cuts or scrapes with proper cleansing and bandaging, and see your doctor when cuts heal slowly or if an infection develops.

Insulin — the hormone that allows your body to regulate sugar in the blood — is made in your pancreas. Essentially, insulin resistance is a state in which the body’s cells do not use insulin efficiently. As a result, it takes more insulin than normal to transport blood sugar (glucose) into cells, to be used immediately for fuel or stored for later use. A drop in efficiency in getting glucose to cells creates a problem for cell function; glucose is normally the body’s quickest and most readily available source of energy.
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.
Diabetes mellitus (diabetes) is a common chronic disease of abnormal carbohydrate, fat, and protein metabolism that affects an estimated 20 million people in the United States, of whom about one third are undiagnosed. There are two major forms recognized, type-1 and type-2. Both are characterized by inappropriately high blood sugar levels (hyperglycemia). In type-1 diabetes the patient can not produce the hormone insulin, while in type-2 diabetes the patient produces insulin, but it is not used properly. An estimated 90% of diabetic patients suffer from type-2 disease. The causes of diabetes are multiple and both genetic and environmental factors contribute to its development. The genetic predisposition for type-2 diabetes is very strong and numerous environmental factors such as diet, lack of exercise, and being overweight are known to also increase one’s risk for diabetes. Diabetes is a dangerous disease which affects the entire body and diabetic patients are at increased risk for heart disease, hypertension, stroke, kidney failure, blindness, neuropathy, and infection when compared to nondiabetic patients. Diabetic patients also have impaired healing when compared to healthy individuals. This is in part due to the dysfunction of certain white blood cells that fight infection.
6. Polycystic ovary syndrome (PCOS): This is a common cause of female infertility and insulin resistance. It can cause signs and symptoms like irregular periods, acne, thinning scalp hair, and excess hair growth on the face and body. High insulin levels also increase the risk of developing diabetes, and about half of women with PCOS develop diabetes.