Type 2 diabetes is mainly caused by insulin resistance. This means no matter how much or how little insulin is made, the body can't use it as well as it should. As a result, glucose can't be moved from the blood into cells. Over time, the excess sugar in the blood gradually poisons the pancreas causing it to make less insulin and making it even more difficult to keep blood glucose under control.

When diabetes occurs in women during pregnancy, it is called gestational diabetes. It usually is diagnosed between the 24th and 28th weeks of pregnancy. Like in type 1 and type 2 diabetes, blood sugar levels become too high. When women are pregnant, more glucose is needed to nourish the developing baby. The body needs more insulin, which is produced by the pancreas. In some women, the body does not produce enough insulin to meet this need, and blood sugar levels rise, resulting in gestational diabetes.

How does type 2 diabetes progress over time? Type 2 diabetes is a progressive disease, meaning that the body’s ability to regulate blood sugar gets worse over time, despite careful management. Over time, the body’s cells become increasingly less responsive to insulin (increased insulin resistance) and beta cells in the pancreas produce less and less insulin (called beta-cell burnout). In fact, when people are diagnosed with type 2 diabetes, they usually have already lost up to 50% or more of their beta cell function. As type 2 diabetes progresses, people typically need to add one or more different types of medications. The good news is that there are many more choices available for treatments, and a number of these medications don’t cause as much hypoglycemia, hunger and/or weight gain (e.g., metformin, pioglitazone, DPP-4 inhibitors, GLP-1 agonists, SGLT-2 inhibitors, and better insulin). Diligent management early on can help preserve remaining beta cell function and sometimes slow progression of the disease, although the need to use more and different types of medications does not mean that you have failed.
The information contained in this monograph is for educational purposes only. This information is not a substitute for professional medical advice, diagnosis, or treatment. If you have or suspect you may have a health concern, consult your professional health care provider. Reliance on any information provided in this monograph is solely at your own risk.
Jump up ^ Picot, J; Jones, J; Colquitt, JL; Gospodarevskaya, E; Loveman, E; Baxter, L; Clegg, AJ (September 2009). "The clinical effectiveness and cost-effectiveness of bariatric (weight loss) surgery for obesity: a systematic review and economic evaluation". Health Technology Assessment. Winchester, England. 13 (41): iii–iv, 1–190, 215–357. doi:10.3310/hta13410. PMID 19726018.
^ Jump up to: a b Petzold A, Solimena M, Knoch KP (October 2015). "Mechanisms of Beta Cell Dysfunction Associated With Viral Infection". Current Diabetes Reports (Review). 15 (10): 73. doi:10.1007/s11892-015-0654-x. PMC 4539350. PMID 26280364. So far, none of the hypotheses accounting for virus-induced beta cell autoimmunity has been supported by stringent evidence in humans, and the involvement of several mechanisms rather than just one is also plausible.

Longer-term, the goals of treatment are to prolong life, reduce symptoms, and prevent diabetes-related complications such as blindness, kidney failure, and amputation of limbs. These goals are accomplished through education, insulin use, meal planning and weight control, exercise, foot care, and careful self-testing of blood glucose levels. Self-testing of blood glucose is accomplished through regular use of a blood glucose monitor (pictured, right). This machine can quickly and easily measure the level of blood glucose based by analysing the level from a small drop of blood that is usually obtained from the tip of a finger. You will also require regular tests for glycated haemoglobin (HbA1c). This measures your overall control over several months.


In type 2 diabetes (formerly called non– insulin-dependent diabetes or adult-onset diabetes), the pancreas often continues to produce insulin, sometimes even at higher-than-normal levels, especially early in the disease. However, the body develops resistance to the effects of insulin, so there is not enough insulin to meet the body’s needs. As type 2 diabetes progresses, the insulin-producing ability of the pancreas decreases.
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]
The body will attempt to dilute the high level of glucose in the blood, a condition called hyperglycemia, by drawing water out of the cells and into the bloodstream in an effort to dilute the sugar and excrete it in the urine. It is not unusual for people with undiagnosed diabetes to be constantly thirsty, drink large quantities of water, and urinate frequently as their bodies try to get rid of the extra glucose. This creates high levels of glucose in the urine.
Oral glucose tolerance test (OGTT): With this test you will be required to fast for at least 8 hours and then are given a drink with 75 g of carbohydrate. Your blood glucose is checked at fasting and then 2 hours after drinking the solution. If your blood glucose is 11.1 mmol/L or higher, your doctor may diagnose diabetes. If your blood glucose 2 hours after drinking the solution is between 7.8 to 11.1 mmol/L, your doctor may diagnose prediabetes. This is the preferred method to test for gestational diabetes.

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.

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.
Type 2 diabetes is most common is those who are genetically predisposed and who are overweight, lead a sedentary lifestyle, have high blood pressure, and/or have insulin resistance due to excess weight. People of certain ethnicities are more likely to develop diabetes, too. These include: African Americans, Mexican Americans, American Indians, Native Hawaiians, Pacific Islanders, and Asian Americans. These populations are more likely to be overweight and have high blood pressure, which increases the risk of developing diabetes.

It will surely be tough eating salads and vegetables when everyone else at your dinner table is eating pizza. Decide that this diagnosis can benefit the health of the entire family. Educate your family about the benefits of eating a healthy diet. Take your children grocery shopping with you. Practice the plate method: Aim to make half your plate non-starchy vegetables; a quarter lean protein; and a quarter whole grains or starchy vegetables, like sweet potatoes. Make exercise part of your daily routine and include your family. Go for walks after dinner. Head to the pool on the weekends, or enroll in an exercise class. If you don't have children, aim to find others with diabetes or friends that can act as your workout partners.
Morbidity and mortality stem from the metabolic derangements and from the long-term complications that affect small and large vessels, resulting in retinopathy, nephropathy, neuropathy, ischemic heart disease, and arterial obstruction with gangrene of extremities.2 The acute clinical manifestations can be fully understood in the context of current knowledge of the secretion and action of insulin.3 Genetic and other etiologic considerations implicate autoimmune mechanisms in the evolution of the most common form of childhood diabetes, known as type 1a diabetes.4,5 Genetic defects in insulin secretion are increasingly recognized and understood as defining the causes of monogenic forms of diabetes such as maturity-onset diabetes of youth (MODY) and neonatal DM and contributing to the spectrum of T2DM.6
There is evidence that certain emotions can promote type 2 diabetes. A recent study found that depression seems to predispose people to diabetes. Other research has tied emotional stress to diabetes, though the link hasn't been proved. Researchers speculate that the emotional connection may have to do with the hormone cortisol, which floods the body during periods of stress. Cortisol sends glucose to the blood, where it can fuel a fight-or-flight response, but overuse of this system may lead to dysfunction.
People usually develop type 2 diabetes after the age of 40 years, although people of South Asian origin are at an increased risk of the condition and may develop diabetes from the age of 25 onwards. The condition is also becoming increasingly common among children and adolescents across all populations. Type 2 diabetes often develops as a result of overweight, obesity and lack of physical activity and diabetes prevalence is on the rise worldwide as these problems become more widespread.
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.

Type 1 diabetes mellitus is characterized by loss of the insulin-producing beta cells of the pancreatic islets, leading to insulin deficiency. This type can be further classified as immune-mediated or idiopathic. The majority of type 1 diabetes is of the immune-mediated nature, in which a T cell-mediated autoimmune attack leads to the loss of beta cells and thus insulin.[38] It causes approximately 10% of diabetes mellitus cases in North America and Europe. Most affected people are otherwise healthy and of a healthy weight when onset occurs. Sensitivity and responsiveness to insulin are usually normal, especially in the early stages. Type 1 diabetes can affect children or adults, but was traditionally termed "juvenile diabetes" because a majority of these diabetes cases were found in children.[citation needed]


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. 

How does type 2 diabetes progress over time? Type 2 diabetes is a progressive disease, meaning that the body’s ability to regulate blood sugar gets worse over time, despite careful management. Over time, the body’s cells become increasingly less responsive to insulin (increased insulin resistance) and beta cells in the pancreas produce less and less insulin (called beta-cell burnout). In fact, when people are diagnosed with type 2 diabetes, they usually have already lost up to 50% or more of their beta cell function. As type 2 diabetes progresses, people typically need to add one or more different types of medications. The good news is that there are many more choices available for treatments, and a number of these medications don’t cause as much hypoglycemia, hunger and/or weight gain (e.g., metformin, pioglitazone, DPP-4 inhibitors, GLP-1 agonists, SGLT-2 inhibitors, and better insulin). Diligent management early on can help preserve remaining beta cell function and sometimes slow progression of the disease, although the need to use more and different types of medications does not mean that you have failed.


interventions The goal of treatment is to maintain insulin glucose homeostasis. Type 1 diabetes is controlled by insulin, meal planning, and exercise. The Diabetes Control and Complications Trial (DCCT), completed in mid-1993, demonstrated that tight control of blood glucose levels (i.e., frequent monitoring and maintenance at as close to normal as possible to the level of nondiabetics) significantly reduces complications such as eye disease, kidney disease, and nerve damage. Type 2 diabetes is controlled by meal planning; exercise; one or more oral agents, in combination with oral agents; and insulin. The results of the United Kingdom Prospective Diabetes Study, which involved more than 5000 people with newly diagnosed type 2 diabetes in the United Kingdom, were comparable to those of the DCCT where a relationship in microvascular complications. Stress of any kind may require medication adjustment in both type 1 and type 2 diabetes.

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 works like a key that opens the doors to cells and lets the glucose in. Without insulin, glucose can't get into the cells (the doors are "locked" and there is no key) and so it stays in the bloodstream. As a result, the level of sugar in the blood remains higher than normal. High blood sugar levels are a problem because they can cause a number of health problems.
The good news is that if you have diabetes, you have a great amount of control in managing your disease. Although it can be difficult to manage a disease on a daily basis, the resources and support for people with diabetes is endless. It's important for you to receive as much education as possible so that you can take advantage of all the good information that is out there (and weed out the bad).
Screening for undiagnosed T2DM is recommended at the first prenatal visit in women with above risk factors, using standard diagnostic method criteria. Screening for gestational diabetes (GDM) at 24-28 wk of gestation is recommended in women who do not have previous history of diabetes, as GDM remains asymptomatic11. A history of GDM carries a high risk for developing diabetes.
If you have type 2 diabetes and your body mass index (BMI) is greater than 35, you may be a candidate for weight-loss surgery (bariatric surgery). Blood sugar levels return to normal in 55 to 95 percent of people with diabetes, depending on the procedure performed. Surgeries that bypass a portion of the small intestine have more of an effect on blood sugar levels than do other weight-loss surgeries.

Patients with Type I diabetes need daily injections of insulin to help their bodies use glucose. The amount and type of insulin required depends on the height, weight, age, food intake, and activity level of the individual diabetic patient. Some patients with Type II diabetes may need to use insulin injections if their diabetes cannot be controlled with diet, exercise, and oral medication. Injections are given subcutaneously, that is, just under the skin, using a small needle and syringe. Injection sites can be anywhere on the body where there is looser skin, including the upper arm, abdomen, or upper thigh.

Diabetes is a serious and costly disease which is becoming increasingly common, especially in developing countries and disadvantaged minorities. However, there are ways of preventing it and/or controlling its progress. Public and professional awareness of the risk factors for, and symptoms of diabetes are an important step towards its prevention and control.


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.
Insulin resistance is the most common cause of type 2 diabetes, but it is possible to have type 2 and not be insulin resistant. You can have a form of type 2 where you body simply doesn’t produce enough insulin; that’s not as common. Researchers aren’t sure what exactly keeps some people from producing enough insulin, but that’s another thing they’re working hard to figure out.
Examples of simple or refined carbohydrates, on the other hand, exist in various forms — from the sucrose in the table sugar you use to bake cookies, to the various kinds of added sugar in packaged snacks, fruit drinks, soda, and cereal. Simple carbohydrates are natural components of many fresh foods, too, such as the lactose in milk and the fructose in fruits, and therefore, a healthy, well-balanced diet will always contain these types of sugars.
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.

Damage to small blood vessels can affect the eyes, kidneys, and nerves. Damage to eyes, specifically the retina, is called diabetic retinopathy and is the leading cause of blindness. Damage to the kidneys, called diabetic nephropathy, can lead to kidney failure and the need for dialysis. Damage to the nerves that supply the legs and arms and gastrointestinal tract is called diabetic neuropathy. Some people with diabetes who develop peripheral neuropathy (damage to the nerves in the legs) and have poor blood flow to the legs may eventually need an amputation.
Although urine can also be tested for the presence of glucose, checking urine is not a good way to monitor treatment or adjust therapy. Urine testing can be misleading because the amount of glucose in the urine may not reflect the current level of glucose in the blood. Blood glucose levels can get very low or reasonably high without any change in the glucose levels in the urine.
John P. Cunha, DO, is a U.S. board-certified Emergency Medicine Physician. Dr. Cunha's educational background includes a BS in Biology from Rutgers, the State University of New Jersey, and a DO from the Kansas City University of Medicine and Biosciences in Kansas City, MO. He completed residency training in Emergency Medicine at Newark Beth Israel Medical Center in Newark, New Jersey.
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