Diabetes may have symptoms in some people, and no symptoms in others. Generally, people with Type 1 diabetes have increased thirst (polydipsia), frequent urination (polyuria), and increased hunger (polyphagia). Symptoms may develop over weeks to months.  Untreated, this condition may cause a person to lose consciousness and become very ill (diabetic ketoacidosis).
The World Health Organization recommends testing those groups at high risk[54] and in 2014 the USPSTF is considering a similar recommendation.[58] High-risk groups in the United States include: those over 45 years old; those with a first degree relative with diabetes; some ethnic groups, including Hispanics, African-Americans, and Native-Americans; a history of gestational diabetes; polycystic ovary syndrome; excess weight; and conditions associated with metabolic syndrome.[23] The American Diabetes Association recommends screening those who have a BMI over 25 (in people of Asian descent screening is recommended for a BMI over 23).[59]
^ Jump up to: a b c Maruthur, NM; Tseng, E; Hutfless, S; Wilson, LM; Suarez-Cuervo, C; Berger, Z; Chu, Y; Iyoha, E; Segal, JB; Bolen, S (19 April 2016). "Diabetes Medications as Monotherapy or Metformin-Based Combination Therapy for Type 2 Diabetes: A Systematic Review and Meta-analysis". Annals of Internal Medicine. 164 (11): 740–51. doi:10.7326/M15-2650. PMID 27088241.
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.
DM is a strong independent predictor of short- and long-term recurrent ischemic events, including mortality, in acute coronary syndrome (ACS),6,7 including unstable angina and non-ST-elevation MI (NSTEMI),8 ST-elevation MI (STEMI) treated medically,9 and ACS undergoing percutaneous coronary intervention (PCI).10,11 Furthermore, the concomitant presence of cardiovascular risk factors and comorbidities that negatively affect the outcomes of ACS is higher in DM patients.12
Type 1 and type 2 diabetes were identified as separate conditions for the first time by the Indian physicians Sushruta and Charaka in 400–500 CE with type 1 associated with youth and type 2 with being overweight.[108] The term "mellitus" or "from honey" was added by the Briton John Rolle in the late 1700s to separate the condition from diabetes insipidus, which is also associated with frequent urination.[108] Effective treatment was not developed until the early part of the 20th century, when Canadians Frederick Banting and Charles Herbert Best isolated and purified insulin in 1921 and 1922.[108] This was followed by the development of the long-acting insulin NPH in the 1940s.[108]
Diabetes is a condition in which the body cannot properly store and use fuel for energy. The body's main fuel is a form of sugar called glucose, which comes from food (after it has been broken down). Glucose enters the blood and is used by cells for energy. To use glucose, the body needs a hormone called insulin that's made by the pancreas. Insulin is important because it allows glucose to leave the blood and enter the body's cells.
Type 2 diabetes, a form of diabetes mellitus, is likely one of the better-known chronic diseases in the world — and that's no surprise. Data from the Centers for Disease Control and Prevention suggest in the United States alone, 30.3 million people, or 9.4 percent of the U.S. population, has diabetes, and the majority of these people have type 2. (1)
At present, the American Diabetes Association does not recommend general screening of the population for type 1 diabetes, though screening of high risk individuals, such as those with a first degree relative (sibling or parent) with type 1 diabetes should be encouraged. Type 1 diabetes tends to occur in young, lean individuals, usually before 30 years of age; however, older patients do present with this form of diabetes on occasion. This subgroup is referred to as latent autoimmune diabetes in adults (LADA). LADA is a slow, progressive form of type 1 diabetes. Of all the people with diabetes, only approximately 10% have type 1 diabetes and the remaining 90% have type 2 diabetes.
All you need to know about insulin sensitivity factor Insulin sensitivity factor is a measurement that describes how blood sugar levels are affected by taking 1 unit of insulin. It can help a person with type 1 diabetes regulate their blood sugar levels. Learn more about what insulin sensitivity factor is, who should test and when, and what the results mean. Read now
The brain depends on glucose as a fuel. As glucose levels drop below 65 mg/dL (3.2 mmol/L) counterregulatory hormones (eg, glucagon, cortisol, epinephrine) are released, and symptoms of hypoglycemia develop. These symptoms include sweatiness, shaking, confusion, behavioral changes, and, eventually, coma when blood glucose levels fall below 30-40 mg/dL.
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Know Your Numbers: Knowing your ABCs—A1c, blood pressure, and cholesterol—are important in reducing your risk for diabetes and keeping your diabetes in good control. If you are someone with diabetes who has elevated blood pressure or cholesterol, you are increasing your risk of heart attack and stroke. Your physician will give you your A1c, blood pressure, and cholesterol targets. Make sure you pay attention to them and understand what they mean and why they are important.
The American Diabetes Association recommends that blood sugars be 80mg/dL-130mg/dL before meals and less than or equal to 180mg/dL two hours after meals. Blood sugar targets are individualized based on a variety of factors such as age, length of diagnosis, if you have other health issues, etc. For example, if you are an elderly person, your targets maybe a bit higher than someone else. Ask your physician what targets are right for you.

Fatigue and muscle weakness occur because the glucose needed for energy simply is not metabolized properly. Weight loss in type 1 diabetes patients occurs partly because of the loss of body fluid and partly because in the absence of sufficient insulin the body begins to metabolize its own proteins and stored fat. The oxidation of fats is incomplete, however, and the fatty acids are converted into ketone bodies. When the kidney is no longer able to handle the excess ketones the patient develops ketosis. The overwhelming presence of the strong organic acids in the blood lowers the pH and leads to severe and potentially fatal ketoacidosis.
Gestational diabetes mellitus (GDM) resembles type 2 DM in several respects, involving a combination of relatively inadequate insulin secretion and responsiveness. It occurs in about 2–10% of all pregnancies and may improve or disappear after delivery.[50] However, after pregnancy approximately 5–10% of women with GDM are found to have DM, most commonly type 2.[50] GDM is fully treatable, but requires careful medical supervision throughout the pregnancy. Management may include dietary changes, blood glucose monitoring, and in some cases, insulin may be required.

Assemble a Medical Team: Whether you've had diabetes for a long time or you've just been diagnosed, there are certain doctors that are important to see. It is extremely important to have a good primary care physician. This type of doctor will help coordinate appointments for other physicians if they think that you need it. Some primary physicians treat diabetes themselves, whereas others will recommend that you visit an endocrinologist for diabetes treatment. An endocrinologist is a person who specializes in diseases of the endocrine system, diabetes being one of them.
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]
There are some interesting developments in blood glucose monitoring including continuous glucose sensors. The new continuous glucose sensor systems involve an implantable cannula placed just under the skin in the abdomen or in the arm. This cannula allows for frequent sampling of blood glucose levels. Attached to this is a transmitter that sends the data to a pager-like device. This device has a visual screen that allows the wearer to see, not only the current glucose reading, but also the graphic trends. In some devices, the rate of change of blood sugar is also shown. There are alarms for low and high sugar levels. Certain models will alarm if the rate of change indicates the wearer is at risk for dropping or rising blood glucose too rapidly. One version is specifically designed to interface with their insulin pumps. In most cases the patient still must manually approve any insulin dose (the pump cannot blindly respond to the glucose information it receives, it can only give a calculated suggestion as to whether the wearer should give insulin, and if so, how much). However, in 2013 the US FDA approved the first artificial pancreas type device, meaning an implanted sensor and pump combination that stops insulin delivery when glucose levels reach a certain low point. All of these devices need to be correlated to fingersticks measurements for a few hours before they can function independently. The devices can then provide readings for 3 to 5 days.
Know Your Numbers: Knowing your ABCs—A1c, blood pressure, and cholesterol—are important in reducing your risk for diabetes and keeping your diabetes in good control. If you are someone with diabetes who has elevated blood pressure or cholesterol, you are increasing your risk of heart attack and stroke. Your physician will give you your A1c, blood pressure, and cholesterol targets. Make sure you pay attention to them and understand what they mean and why they are important.
Patients need to ensure that their blood glucose levels are kept as normal as possible so that delicate tissues in the body (especially blood vessels in the eyes, kidneys and peripheral nerves) are not damaged by high glucose levels over a long period of time. To achieve this, patients need to measure their glucose regularly and learn how to adjust their insulin doses in order to optimise their glucose levels (diabetes control). Good diabetes control helps to minimise the risk of long-term diabetes complications, as well as short-term symptoms (such as thirst).

If sugars in general are not associated with increased diabetes risk, but sodas are, it suggests the possibility that something other than sugar explains this relationship.16 Sodas are often accompanied by cheeseburgers, chicken nuggets, and other unhealthful foods. That is, soda consumption can be a sign of a diet focusing on fast foods or an overall unhealthful diet and lifestyle. And sugary snack foods (e.g., cookies and snack pastries) are often high in fat; the sugar lures us in to the fat calories hiding inside. Some, but not all, observational trials have sought to control for these confounding variables. 


Diabetes mellitus (“diabetes”) and hypertension, which commonly coexist, are global public health issues contributing to an enormous burden of cardiovascular disease, chronic kidney disease, and premature mortality and disability. The presence of both conditions has an amplifying effect on risk for microvascular and macrovascular complications.1 The prevalence of diabetes is rising worldwide (Fig. 37.1). Both diabetes and hypertension disproportionately affect people in middle and low-income countries, and an estimated 70% of all cases of diabetes are found in these countries.2,3 In the United States alone, the total costs of care for diabetes and hypertension in the years 2012 and 2011 were 245 and 46 billion dollars, respectively.4,5 Therefore, there is a great potential for meaningful health and economic gains attached to prevention, detection, and intervention for diabetes and hypertension.
2.Retinopathy - Diabetes may cause blood vessels in the retina (the light sensitive lining of the eye) to become leaky, blocked, or grow abnormally [Figure 1]. Retinopathy is rare before the age of 10 and the risk increases with the length of time a person has diabetes. Treatments such as laser, injections in the eye, or other procedures may be helpful to prevent visual loss or restore sight. The longer a patient has diabetes, the greater chance of developing an eye problem.  All patients with diabetes are at risk for developing retinopathy, but the risk is higher for patients with worse blood sugar control.  Early retinopathy may have no symptoms, but early treatment is essential to prevent any loss of vision.
Insulin is needed to allow glucose to pass from the blood into most of the body cells. Only the cells of the brain and central nervous system can use glucose from the blood in the absence of insulin. Without insulin, most body cells metabolize substances other than glucose for energy. However, fat metabolism in the absence of glucose metabolism, creates ketone bodies which are poisonous and their build up is associated with hyperglycemic coma. In the absence of sufficient insulin, unmetabolized glucose builds up in the blood. Water is drawn from body cells by osmosis to dilute the highly concentrated blood, and is then excreted along with much of the glucose, once the renal threshold for glucose (usually 10 mmol/L) is exceeded. Dehydration follows.

How does high blood sugar (hyperglycemia) feel? To maintain the right amount of blood sugar, the body needs insulin, a hormone that delivers this sugar to the cells. When insulin is lacking, blood sugar builds up. We describe symptoms of high blood sugar, including fatigue, weight loss, and frequent urination. Learn who is at risk and when to see a doctor here. Read now
People with glucose levels between normal and diabetic have impaired glucose tolerance (IGT) or insulin resistance. People with impaired glucose tolerance do not have diabetes, but are at high risk for progressing to diabetes. Each year, 1% to 5% of people whose test results show impaired glucose tolerance actually eventually develop diabetes. Weight loss and exercise may help people with impaired glucose tolerance return their glucose levels to normal. In addition, some physicians advocate the use of medications, such as metformin (Glucophage), to help prevent/delay the onset of overt diabetes.
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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.
When your blood sugar is out of whack, you just don’t feel well, says Cypress, and might become more short-tempered. In fact, high blood sugar can mimic depression-like symptoms. “You feel very tired, you don’t feel like doing anything, you don’t want to go out, you just want to sleep,” Cypress says. She’ll see patients who think they need to be treated for depression, but then experience mood improvement after their blood sugar normalizes.
Jump up ^ Palmer, Suetonia C.; Mavridis, Dimitris; Nicolucci, Antonio; Johnson, David W.; Tonelli, Marcello; Craig, Jonathan C.; Maggo, Jasjot; Gray, Vanessa; De Berardis, Giorgia; Ruospo, Marinella; Natale, Patrizia; Saglimbene, Valeria; Badve, Sunil V.; Cho, Yeoungjee; Nadeau-Fredette, Annie-Claire; Burke, Michael; Faruque, Labib; Lloyd, Anita; Ahmad, Nasreen; Liu, Yuanchen; Tiv, Sophanny; Wiebe, Natasha; Strippoli, Giovanni F.M. (19 July 2016). "Comparison of Clinical Outcomes and Adverse Events Associated With Glucose-Lowering Drugs in Patients With Type 2 Diabetes". JAMA: the Journal of the American Medical Association. 316 (3): 313–24. doi:10.1001/jama.2016.9400. PMID 27434443.
Hyperglycemic hyperosmolar nonketotic syndrome (HHNS). Signs and symptoms of this life-threatening condition include a blood sugar reading higher than 600 mg/dL (33.3 mmol/L), dry mouth, extreme thirst, fever greater than 101 F (38 C), drowsiness, confusion, vision loss, hallucinations and dark urine. Your blood sugar monitor may not be able to give you an exact reading at such high levels and may instead just read "high."

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Insulin is only recommended for individuals for type 2 diabetics when they have not been able to get blood sugars low enough to prevent complications through other means. To avoid insulin, those with this health condition should work very hard to follow a healthy eating plan that includes a lot of vegetables and lean proteins, exercise every day, and keep stress in perspective. They also should take their oral drugs regularly. It can be difficult to follow these recommendations and the help of your doctor, nutritionist, diabetes educator, health coach, or integrative medicine practitioner may be helpful. If you who want to avoid taking medicine, work with health professionals who are knowledgeable about lifestyle medicine, and can help you understand how to fit the changes into your life.


The American Diabetes Association sponsored an international panel in 1995 to review the literature and recommend updates of the classification of diabetes mellitus. The definitions and descriptions that follow are drawn from the Report of the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. The report was first approved in 1997 and modified in 1999. Although other terms are found in older literature and remain in use, their use in current clinical practice is inappropriate. Epidemiologic and research studies are facilitated by use of a common language.
The WHO estimates that diabetes mellitus resulted in 1.5 million deaths in 2012, making it the 8th leading cause of death.[9][101] However another 2.2 million deaths worldwide were attributable to high blood glucose and the increased risks of cardiovascular disease and other associated complications (e.g. kidney failure), which often lead to premature death and are often listed as the underlying cause on death certificates rather than diabetes.[101][104] For example, in 2014, the International Diabetes Federation (IDF) estimated that diabetes resulted in 4.9 million deaths worldwide,[19] using modeling to estimate the total number of deaths that could be directly or indirectly attributed to diabetes.[20]
Type 1 Diabetes: About 5 to 10 percent of those with diabetes have type 1 diabetes. It's an autoimmune disease, meaning the body's own immune system mistakenly attacks and destroys the insulin-producing cells in the pancreas. Patients with type 1 diabetes have very little or no insulin, and must take insulin everyday. Although the condition can appear at any age, typically it's diagnosed in children and young adults, which is why it was previously called juvenile diabetes.
In autoimmune diseases, such as type 1 diabetes, the immune system mistakenly manufactures antibodies and inflammatory cells that are directed against and cause damage to patients' own body tissues. In persons with type 1 diabetes, the beta cells of the pancreas, which are responsible for insulin production, are attacked by the misdirected immune system. It is believed that the tendency to develop abnormal antibodies in type 1 diabetes is, in part, genetically inherited, though the details are not fully understood.
How does high blood sugar (hyperglycemia) feel? To maintain the right amount of blood sugar, the body needs insulin, a hormone that delivers this sugar to the cells. When insulin is lacking, blood sugar builds up. We describe symptoms of high blood sugar, including fatigue, weight loss, and frequent urination. Learn who is at risk and when to see a doctor here. Read now
Type 2 diabetes is a condition of blood sugar dysregulation. In general blood sugar is too high, but it also can be too low. This can happen if you take medications then skip a meal. Blood sugar also can rise very quickly after a high glycemic index meal, and then fall a few hours later, plummeting into hypoglycemia (low blood sugar). The signs and symptoms of hypoglycemia can include
To measure blood glucose levels, a blood sample is usually taken after people have fasted overnight. However, it is possible to take blood samples after people have eaten. Some elevation of blood glucose levels after eating is normal, but even after a meal the levels should not be very high. Fasting blood glucose levels should never be higher than 125 mg/dL. Even after eating, blood glucose levels should not be higher than 199 mg/dL.
Cataracts and glaucoma are also more common among diabetics. It is also important to note that since the lens of the eye lets water through, if blood sugar concentrations vary a lot, the lens of the eye will shrink and swell with fluid accordingly. As a result, blurry vision is very common in poorly controlled diabetes. Patients are usually discouraged from getting a new eyeglass prescription until their blood sugar is controlled. This allows for a more accurate assessment of what kind of glasses prescription is required.
The earliest surviving work with a detailed reference to diabetes is that of Aretaeus of Cappadocia (2nd or early 3rd century CE). He described the symptoms and the course of the disease, which he attributed to the moisture and coldness, reflecting the beliefs of the "Pneumatic School". He hypothesized a correlation of diabetes with other diseases, and he discussed differential diagnosis from the snakebite which also provokes excessive thirst. His work remained unknown in the West until 1552, when the first Latin edition was published in Venice.[110]
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.

When there is excess glucose present in the blood, as with type 2 diabetes, the kidneys react by flushing it out of the blood and into the urine. This results in more urine production and the need to urinate more frequently, as well as an increased risk of urinary tract infections (UTIs) in men and women. People with type 2 diabetes are twice as likely to get a UTI as people without the disease, and the risk is higher in women than in men.
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