Commonly, diabetic patients’ random blood glucose measurement will be greater than 200 mg/dL. Additionally, diabetic patients’ urinalysis will be positive for greater than 30 mg/g of microalbumin on at least two of three consecutive sampling dates. Type 2 diabetics who have had diabetes mellitus for more than 2 years will usually have a fasting C-peptide level greater than 1.0 ng/dL. Patients with type 1 diabetes will have islet cell and anti-insulin autoantibodies present in their blood within 6 months of diagnosis. These antibodies, though, usually fade after 6 months.
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.
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.
Hypoglycemic reactions are promptly treated by giving carbohydrates (orange juice, hard candy, honey, or any sugary food); if necessary, subcutaneous or intramuscular glucagon or intravenous dextrose (if the patient is not conscious) is administered. Hyperglycemic crises are treated initially with prescribed intravenous fluids and insulin and later with potassium replacement based on laboratory values.

Information on mortality rates for type 1 diabetes mellitus is difficult to ascertain without complete national registers of childhood diabetes, although age-specific mortality is probably double that of the general population. [35, 36] Children aged 1-4 years are particularly at risk and may die due to DKA at the time of diagnosis. Adolescents are also a high-risk group. Most deaths result from delayed diagnosis or neglected treatment and subsequent cerebral edema during treatment for DKA, although untreated hypoglycemia also causes some deaths. Unexplained death during sleep may also occur and appears more likely to affect young males. [37]
Type 2 diabetes is usually associated with being overweight (BMI greater than 25), and is harder to control when food choices are not adjusted, and you get no physical activity. And while it’s true that too much body fat and physical inactivity (being sedentary) does increase the likelihood of developing type 2, even people who are fit and trim can develop this type of diabetes.2,3
Persons with diabetes are prone to infection, delayed healing, and vascular disease. The ease with which poorly controlled diabetic persons develop an infection is thought to be due in part to decreased chemotaxis of leukocytes, abnormal phagocyte function, and diminished blood supply because of atherosclerotic changes in the blood vessels. An impaired blood supply means a deficit in the protective defensive cells transported in the blood. Excessive glucose allows organisms to grow out of control.
Insulin, a hormone released from the pancreas (an organ behind the stomach that also produces digestive enzymes), controls the amount of glucose in the blood. Glucose in the bloodstream stimulates the pancreas to produce insulin. Insulin helps glucose to move from the blood into the cells. Once inside the cells, glucose is converted to energy, which is used immediately, or the glucose is stored as fat or glycogen until it is needed.
Low glycemic index foods also may be helpful. The glycemic index is a measure of how quickly a food causes a rise in your blood sugar. Foods with a high glycemic index raise your blood sugar quickly. Low glycemic index foods may help you achieve a more stable blood sugar. Foods with a low glycemic index typically are foods that are higher in fiber.
The roots of type 2 diabetes remain in insulin resistance and pancreatic failure, and the blame for the current diabetes epidemic lies in an overall dietary pattern emphasizing meat, dairy products, and fatty foods, aided and abetted by sugary foods and beverages, rather than simply in sugar alone. A diet emphasizing vegetables, fruits, whole grains, and legumes and avoiding animal products helps prevent diabetes and improves its management when it has been diagnosed. 
Sugary breath isn’t as sweet as it seems.  Diabetics often notice that they’ve developed sweet or nail-polish-like breath before they’re diagnosed. However, if you’re dealing with this strange symptom, time is of the essence. Sweet breath is often a sign of diabetic ketoacidosis, a condition in which your body can’t effectively convert glucose into energy, keeping your blood sugar at dangerous—potentially fatal—levels if untreated.
Some patients with type 2 DM can control their disease with a calorically restricted diet (for instance 1600 to 1800 cal/day), regular aerobic exercise, and weight loss. Most patients, however, require the addition of some form of oral hypoglycemic drug or insulin. Oral agents to control DM include sulfonylurea drugs (such as glipizide), which increase pancreatic secretion of insulin; biguanides or thiazolidinediones (such as metformin or pioglitazone), which increase cellular sensitivity to insulin; or a-glucosidase inhibitors (such as acarbose), which decrease the absorption of carbohydrates from the gastrointestinal tract. Both types of diabetics also may be prescribed pramlintide (Symlin), a synthetic analog of human amylin, a hormone manufactured in the pancreatic beta cells. It enhances postprandial glucose control by slowing gastric emptying, decreasing postprandial glucagon concentrations, and regulating appetite and food intake; thus pramlintide is helpful for patients who do not achieve optimal glucose control with insulin and/or oral antidiabetic agents. When combinations of these agents fail to normalize blood glucose levels, insulin injections are added. Tight glucose control can reduce the patient’s risk of many of the complications of the disease. See: illustration
In the United States alone, more than 8 million people have undiagnosed diabetes, according to the American Diabetes Association. But you don't need to become a statistic. Understanding possible diabetes symptoms can lead to early diagnosis and treatment — and a lifetime of better health. If you're experiencing any of the following diabetes signs and symptoms, see your doctor.

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.

Environmental factors are important, because even identical twins have only a 30-60% concordance for type 1 diabetes mellitus and because incidence rates vary in genetically similar populations under different living conditions. [25] No single factor has been identified, but infections and diet are considered the 2 most likely environmental candidates.
Test Your Blood Sugar: Blood sugar testing is an important part of helping to manage your diabetes. Whether you choose to do selective blood sugar testing or test your blood sugar at the same times daily, blood sugar testing gives you another piece of information and can help you change your diet and adjust your fitness routine or medicines. Keeping your blood sugars at target will help to reduce diabetes complications.
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).
^ 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.
The most common complication of treating high blood glucose levels is low blood glucose levels (hypoglycemia). The risk is greatest for older people who are frail, who are sick enough to require frequent hospital admissions, or who are taking several drugs. Of all available drugs to treat diabetes, long-acting sulfonylurea drugs are most likely to cause low blood glucose levels in older people. When they take these drugs, they are also more likely to have serious symptoms, such as fainting and falling, and to have difficulty thinking or using parts of the body due to low blood glucose levels.
People with these risk factors should be screened for diabetes at least once every three years. Diabetes risk can be estimated using online risk calculators. Doctors may measure fasting blood glucose levels and hemoglobin A1C level, or do an oral glucose tolerance test. If the test results are on the border between normal and abnormal, doctors do the screening tests more often, at least once a year.
The relationship between type 2 diabetes and the main modifiable risk factors (excess weight, unhealthy diet, physical inactivity and tobacco use) is similar in all regions of the world. There is growing evidence that the underlying determinants of diabetes are a reflection of the major forces driving social, economic and cultural change: globalization, urbanization, population aging, and the general health policy environment.[74]
Then, your blood sugar levels get too high. High blood sugar can have a deleterious effect on many parts of your body, including heart, blood vessels, nerves, eyes, and kidneys. Those who are overweight, don’t exercise enough, or have a history of type 2 diabetes in their family are more likely to get the disease. Maintaining a healthy weight, eating a healthy diet, and getting enough exercise can prevent type 2 diabetes. If you have a history of diabetes in your family, or if you are overweight, stay ahead of the disease by making healthy lifestyle choices and changing your diet.
Diabetes has been coined the “silent killer” because the symptoms are so easy to miss. Over 24 million people in America have diabetes, so this is no tiny issue. Kids years ago hardly ever knew another child with diabetes, but such is no longer the case. Approximately 1.25 million children in the United States living with diabetes, which is very telling for state of health in America in 2016 when children are having to endure a medical lifestyle at such a young age.
The classic symptoms of diabetes are polyuria (frequent urination), polydipsia (increased thirst), polyphagia (increased hunger), and weight loss.[23] Other symptoms that are commonly present at diagnosis include a history of blurred vision, itchiness, peripheral neuropathy, recurrent vaginal infections, and fatigue.[13] Many people, however, have no symptoms during the first few years and are diagnosed on routine testing.[13] A small number of people with type 2 diabetes mellitus can develop a hyperosmolar hyperglycemic state (a condition of very high blood sugar associated with a decreased level of consciousness and low blood pressure).[13]
"Secondary" diabetes refers to elevated blood sugar levels from another medical condition. Secondary diabetes may develop when the pancreatic tissue responsible for the production of insulin is destroyed by disease, such as chronic pancreatitis (inflammation of the pancreas by toxins like excessive alcohol), trauma, or surgical removal of the pancreas.
Higher levels of sugar in the urine and the vagina can become a breeding ground for the bacteria and yeast that cause these infections. Recurrent infections are particularly worrisome. “Usually when you keep getting infections, doctors will check for diabetes if you don’t already have it,” says Cypress. “Even women who go to the emergency room for urinary tract infections are often checked.” Don’t miss these other silent diabetes complications you need to know about.
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.
Insulin is a hormone made by your pancreas that acts like a key to let blood sugar into the cells in your body for use as energy. If you have type 2 diabetes, cells don’t respond normally to insulin; this is called insulin resistance. Your pancreas makes more insulin to try to get cells to respond. Eventually your pancreas can’t keep up, and your blood sugar rises, setting the stage for prediabetes and type 2 diabetes. High blood sugar is damaging to the body and can cause other serious health problems, such as heart disease, vision loss, and kidney disease.

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.  
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.
Diabetes is a metabolic disorder that occurs when your blood sugar (glucose), is too high (hyperglycemia). Glucose is what the body uses for energy, and the pancreas produces a hormone called insulin that helps convert the glucose from the food you eat into energy. When the body either does not produce enough insulin, does not produce any at all, or your body becomes resistant to the insulin, the glucose does not reach your cells to be used for energy. This results in the health condition termed diabetes.

You have a higher risk of type 2 diabetes if you are older, have obesity, have a family history of diabetes, or do not exercise. Having prediabetes also increases your risk. Prediabetes means that your blood sugar is higher than normal but not high enough to be called diabetes. If you are at risk for type 2 diabetes, you may be able to delay or prevent developing it by making some lifestyle changes.
Patient Education. Successful management of diabetes requires that the patient actively participate in and be committed to the regimen of care. The problem of poor control can cause serious or even deadly short-term and long-term complications, with devastating effects on the patient's longevity and sense of well being. There are many teaching aids available to help persons with diabetes understand their disease and comply with prescribed therapy. In general, a patient education program should include the following components:
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]
DM affects at least 16 million U.S. residents, ranks seventh as a cause of death in the United States, and costs the national economy over $100 billion yearly. The striking increase in the prevalence of DM in the U.S. during recent years has been linked to a rise in the prevalence of obesity. About 95% of those with DM have Type 2, in which the pancreatic beta cells retain some insulin-producing potential, and the rest have Type 1, in which exogenous insulin is required for long-term survival. In Type 1 DM, which typically causes symptoms before age 25, an autoimmune process is responsible for beta cell destruction. Type 2 DM is characterized by insulin resistance in peripheral tissues as well as a defect in insulin secretion by beta cells. Insulin regulates carbohydrate metabolism by mediating the rapid transport of glucose and amino acids from the circulation into muscle and other tissue cells, by promoting the storage of glucose in liver cells as glycogen, and by inhibiting gluconeogenesis. The normal stimulus for the release of insulin from the pancreas is a rise in the concentration of glucose in circulating blood, which typically occurs within a few minutes after a meal. When such a rise elicits an appropriate insulin response, so that the blood level of glucose falls again as it is taken into cells, glucose tolerance is said to be normal. The central fact in DM is an impairment of glucose tolerance of such a degree as to threaten or impair health. Long recognized as an independent risk factor for cardiovascular disease, DM is often associated with other risk factors, including disorders of lipid metabolism (elevation of very-low-density lipoprotein cholesterol and triglycerides and depression of high-density lipoprotein cholesterol), obesity, hypertension, and impairment of renal function. Sustained elevation of serum glucose and triglycerides aggravates the biochemical defect inherent in DM by impairing insulin secretion, insulin-mediated glucose uptake by cells, and hepatic regulation of glucose output. Long-term consequences of the diabetic state include macrovascular complications (premature or accelerated atherosclerosis with resulting coronary, cerebral, and peripheral vascular insufficiency) and microvascular complications (retinopathy, nephropathy, and neuropathy). It is estimated that half those with DM already have some complications when the diagnosis is made. The American Diabetes Association (ADA) recommends screening for DM for people with risk factors such as obesity, age 45 years or older, family history of DM, or history of gestational diabetes. If screening yields normal results, it should be repeated every 3 years. The diagnosis of DM depends on measurement of plasma glucose concentration. The diagnosis is confirmed when any two measurements of plasma glucose performed on different days yield levels at or above established thresholds: in the fasting state, 126 mg/dL (7 mmol/L); 2 hours postprandially (after a 75-g oral glucose load) or at random, 200 mg/dL (11.1 mmol/L). A fasting plasma glucose of 100-125 mg/dL (5.5-6.9 mmol/L) or a 2-hour postprandial glucose of 140-199 mg/dL (7.8-11 mmol/L) is defined as impaired glucose tolerance. People with impaired glucose tolerance are at higher risk of developing DM within 10 years. For such people, lifestyle modification such as weight reduction and exercise may prevent or postpone the onset of frank DM. Current recommendations for the management of DM emphasize education and individualization of therapy. Controlled studies have shown that rigorous maintenance of plasma glucose levels as near to normal as possible at all times substantially reduces the incidence and severity of long-term complications, particularly microvascular complications. Such control involves limitation of dietary carbohydrate and saturated fat; monitoring of blood glucose, including self-testing by the patient and periodic determination of glycosylated hemoglobin; and administration of insulin (particularly in Type 1 DM), drugs that stimulate endogenous insulin production (in Type 2 DM), or both. The ADA recommends inclusion of healthful carbohydrate-containing foods such as whole grains, fruits, vegetables, and low-fat milk in a diabetic diet. Restriction of dietary fat to less than 10% of total calories is recommended for people with diabetes, as for the general population. Further restriction may be appropriate for those with heart disease or elevated cholesterol or triglyceride levels. The ADA advises that high-protein, low-carbohydrate diets have no particular merit in long-term weight control or in maintenance of a normal plasma glucose level in DM. Pharmaceutical agents developed during the 1990s improve control of DM by enhancing responsiveness of cells to insulin, counteracting insulin resistance, and reducing postprandial carbohydrate absorption. Tailor-made insulin analogues produced by recombinant DNA technology (for example, lispro, aspart, and glargine insulins) have broadened the range of pharmacologic properties and treatment options available. Their use improves both short-term and long-term control of plasma glucose and is associated with fewer episodes of hypoglycemia. SEE ALSO insulin resistance
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If you are at increased risk of diabetes, have symptoms of diabetes, or have pre-diabetes (a major warning sign for diabetes), your doctor will check to see if you have diabetes. Your doctor may also check to see if you have diabetes if you are over the age of 45, have a family history of the disease, are overweight, or if you are at increased risk for another reason. The tests used to check for diabetes are the same tests used to check for pre-diabetes.
Hypoglycemia. Hypoglycemia or “insulin shock” is a common concern in DM management. It typically develops when a diabetic patient takes his or her normal dose of insulin without eating normally. As a result, the administered insulin can push the blood sugar to potentially dangerously low levels. Initially the patient may experience, sweating, nervousness, hunger and weakness. If the hypoglycemic patient is not promptly given sugar (sugar, cola, cake icing), he or she may lose consciousness and even lapse into coma. Questions and Answers about Diabetes and Your Mouth Q: If I have diabetes, will I develop the oral complications that were mentioned? A: It depends. There is a two-way relationship between your oral health and how well your blood sugar is controlled (glycemic control). Poor control of your blood sugar increases your risk of developing the multitude of complications associated with diabetes, including oral complications. Conversely, poor oral health interferes with proper glucose stabilization. Indeed, recent research has shown that diabetic patients who improve their oral health experience a modest improvement in their blood sugar levels. In essence, “Healthy mouths mean healthy bodies.” Q: What are the complications of diabetes therapy that can impact my oral health? A: One of the most worrisome urgent complications associated with diabetes management is the previously described hypoglycemia or insulin shock. In addition, many of the medications prescribed to treat diabetes and its complications, such as hypertension and heart disease, may induce adverse side effects affecting the mouth. Common side effects include dry mouth, taste aberrations, and mouth sores. Q: I have type-2 diabetes. Are my dental problems different than those experienced by people with type-1 diabetes? A: No. All patients with diabetes are at increased risk for the development of dental disease. What is different is that type-2 disease tends to progress more slowly than type-1 disease. Thus, most type-2 diabetes patients are diagnosed later in life, a time in which they are likely to already have existing dental problems. Remember, there is no dental disease unique to diabetes. Uncontrolled or poorly controlled diabetes simply compromises your body’s ability to control the existing disease.
Along with following your diabetes care plan, you may need diabetes medicines, which may include pills or medicines you inject under your skin, such as insulin. Over time, you may need more than one diabetes medicine to manage your blood glucose. Even if you don’t take insulin, you may need it at special times, such as during pregnancy or if you are in the hospital. You also may need medicines for high blood pressure, high cholesterol, or other conditions.
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)
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
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).
If the amount of insulin available is insufficient, or if cells respond poorly to the effects of insulin (insulin insensitivity or insulin resistance), or if the insulin itself is defective, then glucose will not be absorbed properly by the body cells that require it, and it will not be stored appropriately in the liver and muscles. The net effect is persistently high levels of blood glucose, poor protein synthesis, and other metabolic derangements, such as acidosis.[60]
Clear evidence suggests a genetic component in type 1 diabetes mellitus. Monozygotic twins have a 60% lifetime concordance for developing type 1 diabetes mellitus, although only 30% do so within 10 years after the first twin is diagnosed. In contrast, dizygotic twins have only an 8% risk of concordance, which is similar to the risk among other siblings.
Diabetes is a metabolic disorder that occurs when your blood sugar (glucose), is too high (hyperglycemia). Glucose is what the body uses for energy, and the pancreas produces a hormone called insulin that helps convert the glucose from the food you eat into energy. When the body does not produce enough insulin - or does not produce any at all - the glucose does not reach your cells to be used for energy. This results in diabetes.
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