What is type 2 diabetes and prediabetes? Behind type 2 diabetes is a disease where the body’s cells have trouble responding to insulin – this is called insulin resistance. Insulin is a hormone needed to store the energy found in food into the body’s cells. In prediabetes, insulin resistance starts growing and the beta cells in the pancreas that release insulin will try to make even more insulin to make up for the body’s insensitivity. This can go on for a long time without any symptoms. Over time, though, the beta cells in the pancreas will fatigue and will no longer be able to produce enough insulin – this is called “beta burnout.” Once there is not enough insulin, blood sugars will start to rise above normal. Prediabetes causes people to have higher-than-normal blood sugars (and an increased risk for heart disease and stroke). Left unnoticed or untreated, blood sugars continue to worsen and many people progress to type 2 diabetes. After a while, so many of the beta cells have been damaged that diabetes becomes an irreversible condition. 
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.
Nerve damage (neuropathy). Excess sugar can injure the walls of the tiny blood vessels (capillaries) that nourish your nerves, especially in the legs. This can cause tingling, numbness, burning or pain that usually begins at the tips of the toes or fingers and gradually spreads upward. Poorly controlled blood sugar can eventually cause you to lose all sense of feeling in the affected limbs. Damage to the nerves that control digestion can cause problems with nausea, vomiting, diarrhea or constipation. For men, erectile dysfunction may be an issue.
The more common form of diabetes, Type II, occurs in approximately 3-5% of Americans under 50 years of age, and increases to 10-15% in those over 50. More than 90% of the diabetics in the United States are Type II diabetics. Sometimes called age-onset or adult-onset diabetes, this form of diabetes occurs most often in people who are overweight and who do not exercise. It is also more common in people of Native American, Hispanic, and African-American descent. People who have migrated to Western cultures from East India, Japan, and Australian Aboriginal cultures also are more likely to develop Type II diabetes than those who remain in their original countries.
Type 1 diabetes occurs when the immune system attacks and destroys the insulin-producing cells in the pancreas (the beta cells). As a result, the body is left without enough insulin to function normally (i.e. it becomes insulin deficient). This is called an autoimmune reaction, because the body attacks itself and produces antibodies to its own insulin-producing cells, thereby destroying them.

Is it your fault for getting type 2 diabetes? No – type 2 diabetes is not a personal failing. It develops through a combination of factors that are still being uncovered and better understood. Lifestyle (food, exercise, stress, sleep) certainly plays a major role, but genetics play a significant role as well. Type 2 diabetes is often described in the media as a result of being overweight, but the relationship is not that simple. Many overweight individuals never get type 2, and some people with type 2 were never overweight, (although obesity is probably an underlying cause of insulin resistance). To make matters worse, when someone gains weight (for whatever reason), the body makes it extremely difficult to lose the new weight and keep it off. If it were just a matter of choice or a bit of willpower, we would probably all be skinny. At its core, type 2 involves two physiological issues: resistance to the insulin made by the person’s beta cells and too little insulin production relative to the amount one needs.


The prognosis for a person with this health condition is estimated to be a life expectancy of 10 years less than a person without diabetes. However, good blood sugar control and taking steps to prevent complications is shortening this gap and people with the condition are living longer than ever before. It can be reversed with diligent attention to changing lifestyle behaviors.
Health.com is part of the Meredith Health Group. All rights reserved. The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments. All products and services featured are selected by our editors. Health.com may receive compensation for some links to products and services on this website. Offers may be subject to change without notice. See the Terms of Service and Privacy Policy (Your California Rights)for more information. Ad Choices | EU Data Subject Requests
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.

The notion is understandable. Blood sugar levels are high in diabetes, so a common idea has held that eating sugar somehow triggers the disease process. However, the major diabetes organizations take a different view. The American Diabetes Association1 and Diabetes UK2 have labelled this notion a “myth,” as has the Joslin Diabetes Center,3 which wrote, “Diabetes is not caused by eating too much sugar.” These and other organizations have worked to educate people about the causes of diabetes and the role that foods play in the disease process.
The classic symptoms of diabetes such as polyuria, polydypsia and polyphagia occur commonly in type 1 diabetes, which has a rapid development of severe hyperglycaemia and also in type 2 diabetes with very high levels of hyperglycaemia. Severe weight loss is common only in type 1 diabetes or if type 2 diabetes remains undetected for a long period. Unexplained weight loss, fatigue and restlessness and body pain are also common signs of undetected diabetes. Symptoms that are mild or have gradual development could also remain unnoticed.

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


English Diabetes, Diabetes Mellitus, DIABETES MELLITUS, Unspecified diabetes mellitus, diabetes mellitus, diabetes mellitus (diagnosis), DM, Diabetes mellitus NOS, diabetes NOS, Diabetes Mellitus [Disease/Finding], diabete mellitus, diabetes, disorder diabetes mellitus, diabetes (DM), diabetes mellitus (DM), Diabetes mellitus (E08-E13), Diabetes mellitus, DM - Diabetes mellitus, Diabetes mellitus (disorder), Diabetes mellitus, NOS, Diabetes NOS

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.
1. Monitoring of blood glucose status. In the past, urine testing was an integral part of the management of diabetes, but it has largely been replaced in recent years by self monitoring of blood glucose. Reasons for this are that blood testing is more accurate, glucose in the urine shows up only after the blood sugar level is high, and individual renal thresholds vary greatly and can change when certain medications are taken. As a person grows older and the kidney is less able to eliminate sugar in the urine, the renal threshold rises and less sugar is spilled into the urine. The position statement of the American Diabetes Association on Tests of Glycemia in Diabetes notes that urine testing still plays a role in monitoring in type 1 and gestational diabetes, and in pregnancy with pre-existing diabetes, as a way to test for ketones. All people with diabetes should test for ketones during times of acute illness or stress and when blood glucose levels are consistently elevated.

What are the symptoms of diabetes in women? Diabetes can have different effects on men and women. Learn all about the symptoms of diabetes experienced by women with this article, including how the disease may affect pregnancy and the menopause. This MNT Knowledge Center article will also look at gestational diabetes and the risk factors involved. Read now


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.
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.

Many people, especially those with type 2 diabetes, are overweight or obese. Some people with type 2 diabetes may be able to avoid or delay the need to take drugs by achieving and maintaining a healthy weight. Weight loss is also important in these people because excess weight contributes to complications of diabetes. When people with diabetes have trouble losing weight with diet and exercise alone, doctors may give weight-loss drugs or recommend bariatric surgery (surgery to cause weight loss).
Large, population-based studies in China, Finland and USA have recently demonstrated the feasibility of preventing, or delaying, the onset of diabetes in overweight subjects with mild glucose intolerance (IGT). The studies suggest that even moderate reduction in weight and only half an hour of walking each day reduced the incidence of diabetes by more than one half.
Prevention and treatment involve maintaining a healthy diet, regular physical exercise, a normal body weight, and avoiding use of tobacco.[2] Control of blood pressure and maintaining proper foot care are important for people with the disease.[2] Type 1 DM must be managed with insulin injections.[2] Type 2 DM may be treated with medications with or without insulin.[9] Insulin and some oral medications can cause low blood sugar.[13] Weight loss surgery in those with obesity is sometimes an effective measure in those with type 2 DM.[14] Gestational diabetes usually resolves after the birth of the baby.[15]
People who are obese -- more than 20% over their ideal body weight for their height -- are at particularly high risk of developing type 2 diabetes and its related medical problems. Obese people have insulin resistance. With insulin resistance, the pancreas has to work overly hard to produce more insulin. But even then, there is not enough insulin to keep sugars normal.
The typical symptoms of diabetes mellitus are the three “polys:” polyuria, polydipsia, and polyphagia. Because of insulin deficiency, the assimilation and storage of glucose in muscle adipose tissues, and the liver is greatly diminished. This produces an accumulation of glucose in the blood and creates an increase in its osmolarity. In response to this increased osmotic pressure there is depletion of intracellular water and osmotic diuresis. The water loss creates intense thirst and increased urination. The increased appetite (polyphagia) is not as clearly understood. It may be the result of the body's effort to increase its supply of energy foods even though eating more carbohydrates in the absence of sufficient insulin does not meet the energy needs of the cells.

Rates of diabetes in 1985 were estimated at 30 million, increasing to 135 million in 1995 and 217 million in 2005.[18] This increase is believed to be primarily due to the global population aging, a decrease in exercise, and increasing rates of obesity.[18] The five countries with the greatest number of people with diabetes as of 2000 are India having 31.7 million, China 20.8 million, the United States 17.7 million, Indonesia 8.4 million, and Japan 6.8 million.[109] It is recognized as a global epidemic by the World Health Organization.[1]
Diabetes can also be diagnosed if a blood glucose level taken any time of the day without regards to meals is 11.1 mmol/L or higher, plus you have symptoms characteristic of diabetes (e.g., increase thirst, increase urination, unexplained weight loss). A doctor may also examine the eyes for signs of damage to the blood vessels of the retina (back of the eye). Finally, diabetes mellitus is diagnosed if the 3-month cumulative blood sugar average test, known as hemoglobin A1C or glycated hemoglobin, is 6.5% or higher.
Jump up ^ Qaseem, Amir; Wilt, Timothy J.; Kansagara, Devan; Horwitch, Carrie; Barry, Michael J.; Forciea, Mary Ann (6 March 2018). "Hemoglobin A Targets for Glycemic Control With Pharmacologic Therapy for Nonpregnant Adults With Type 2 Diabetes Mellitus: A Guidance Statement Update From the American College of Physicians". Annals of Internal Medicine. doi:10.7326/M17-0939.
The beta cells may be another place where gene-environment interactions come into play, as suggested by the previously mentioned studies that link beta cell genes with type 2. "Only a fraction of people with insulin resistance go on to develop type 2 diabetes," says Shulman. If beta cells can produce enough insulin to overcome insulin resistance, a factor that may be genetically predetermined, then a person can stay free of diabetes. But if the beta cells don't have good genes propping them up, then diabetes is the more likely outcome in a person with substantial insulin resistance.
Excessive thirst typically goes hand-in-hand with increased urination. As your body pulls water out of the tissues to dilute your blood and to rid your body of sugar through the urine, the urge to drink increases. Many people describe this thirst as an unquenchable one. To stay hydrated, you drink excessive amounts of liquids. And if those liquids contain simple sugars (soda, sweet iced tea, lemonade, or juice, for example) your sugars will skyrocket even higher.
Occasionally, a child with hypoglycemic coma may not recover within 10 minutes, despite appropriate therapy. Under no circumstances should further treatment be given, especially intravenous glucose, until the blood glucose level is checked and still found to be subnormal. Overtreatment of hypoglycemia can lead to cerebral edema and death. If coma persists, seek other causes.

Type 2 diabetes was once rare in children and adolescents but has recently become more common. However, it usually begins in people older than 30 and becomes progressively more common with age. About 26% of people older than 65 have type 2 diabetes. People of certain racial and ethnic backgrounds are at increased risk of developing type 2 diabetes: blacks, Asian Americans, American Indians, and people of Spanish or Latin American ancestry who live in the United States have a twofold to threefold increased risk as compared with whites. Type 2 diabetes also tends to run in families.

observations The onset of type 1 diabetes mellitus is sudden in children. Type 2 diabetes often begins insidiously. Characteristically the course is progressive and includes polyuria, polydipsia, weight loss, polyphagia, hyperglycemia, and glycosuria. The eyes, kidneys, nervous system, skin, and circulatory system may be affected by the long-term complications of either type of diabetes; infections are common; and atherosclerosis often develops. In type 1 diabetes mellitus, when no endogenous insulin is being secreted, ketoacidosis is a constant danger. The diagnosis is confirmed by fasting plasma glucose and history.

Regarding age, data shows that for each decade after 40 years of age regardless of weight there is an increase in incidence of diabetes. The prevalence of diabetes in persons 65 years of age and older is around 25%. Type 2 diabetes is also more common in certain ethnic groups. Compared with a 7% prevalence in non-Hispanic Caucasians, the prevalence in Asian Americans is estimated to be 8.0%, in Hispanics 13%, in blacks around 12.3%, and in certain Native American communities 20% to 50%. Finally, diabetes occurs much more frequently in women with a prior history of diabetes that develops during pregnancy (gestational diabetes).


Blurred vision can result from elevated blood sugar. Similarly, fluid that is pulled from the cells into the bloodstream to dilute the sugar can also be pulled from the lenses of your eyes. When the lens of the eye becomes dry, the eye is unable to focus, resulting in blurry vision. It's important that all people diagnosed with type 2 diabetes have a dilated eye exam shortly after diagnosis. Damage to the eye can even occur before a diagnosis of diabetes exists.
A person of Asian origin aged 35 yr or more with two or more of the above risk factors, should undergo a screening test for diabetes. An oral glucose tolerance test (OGTT) is commonly used as the screening test10. Fasting and 2 h post glucose tests can identify impaired fasting glucose (IFG) (fasting glucose >110 - <125 mg/dl), impaired glucose tolerance (IGT) (2 h glucose >140-<200 mg/dl) and presence of diabetes (fasting > 126 and 2 h glucose >200 mg/dl). If a random blood glucose value is > 150 mg/dl, further confirmation by an OGTT is warranted. Recently, glycosylated haemoglobin (HbA1c) has been recommended as the test for diagnosis of diabetes (>6.5%). Presence of pre-diabetes is indicated by HbA1c values between 5.7 - 6.4 per cent11.

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.
Although the signs of diabetes can begin to show early, sometimes it takes a person a while to recognize the symptoms. This often makes it seem like signs and symptoms of diabetes appear suddenly. That’s why it’s important to pay attention to your body, rather than simply brushing them off. To that end, here are some type 1 and type 2 diabetes symptoms that you may want to watch out for:
Glucose in your body can cause yeast infections. This is because glucose speeds the growth of fungus. There are over-the-counter and prescription medications to treat yeast infections. You can potentially avoid yeast infections by maintaining better control of your blood sugar. Take insulin as prescribed, exercise regularly, reduce your carb intake, choose low-glycemic foods, and monitor your blood sugar.
×