Insulin is a hormone that — in people without diabetes — ferries glucose, or blood sugar, to cells for energy or to be stored for later use. In people with diabetes, cells are resistant to insulin; as a result of this insulin resistance, sugar accumulates in the blood. While eating sugar by itself does not cause insulin resistance, Grieger says, foods with sugar and fat can contribute to weight gain, thereby reducing insulin sensitivity in the body.

The most common test used to diagnose diabetes is the fasting blood glucose. This test measures the glucose levels at a specific moment in time (normal is 80-110 mg/dl). In managing diabetes, the goal is to normalize blood glucose levels. It is generally accepted that by maintaining normalized blood glucose levels, one may delay or even prevent some of the complications associated with diabetes. Measures to manage diabetes include behavioral modification (proper diet, exercise) and drug therapies (oral hypoglycemics, insulin replacement). The choice of therapy prescribed takes into consideration the type and severity of the disease present and patient compliance. The physician may request the patient keep a log of their daily blood glucose measurements, in an effort to better assess therapeutic success. Another commonly obtained test is the hemoglobin A1c (HbA1c), which is a surrogate marker used to assess blood glucose levels over an extended period (2-3 months). This test provides the physician with a good picture of the patient’s glucose levels over time.
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.
Symptoms of type 1 diabetes can start quickly, in a matter of weeks. Symptoms of type 2 diabetes often develop slowly—over the course of several years—and can be so mild that you might not even notice them. Many people with type 2 diabetes have no symptoms. Some people do not find out they have the disease until they have diabetes-related health problems, such as blurred vision or heart trouble.
Also striking are the differences in incidence between mainland Italy (8.4 cases per 100,000 population) and the Island of Sardinia (36.9 cases per 100,000 population). These variations strongly support the importance of environmental factors in the development of type 1 diabetes mellitus. Most countries report that incidence rates have at least doubled in the last 20 years. Incidence appears to increase with distance from the equator. [31]
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
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.
Type 2 diabetes is the most common type of diabetes. It is a chronic problem in which blood glucose (sugar) can no longer be regulated. There are two reasons for this. First, the cells of the body become resistant to insulin (insulin resistant). Insulin works like a key to let glucose (blood sugar) move out of the blood and into the cells where it is used as fuel for energy. When the cells become insulin resistant, it requires more and more insulin to move sugar into the cells, and too much sugar stays in the blood. Over time, if the cells require more and more insulin, the pancreas can't make enough insulin to keep up and begins to fail.
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.
Although there are dozens of known type 1 genes, about half of the risk attributable to heredity comes from a handful that coordinate a part of the immune system called HLA, which helps the body recognize nefarious foreign invaders, such as viruses, bacteria, and parasites. Type 1 diabetes is an autoimmune disease, in which the body's own immune system destroys the cells in the pancreas that produce insulin, so perhaps it is no surprise that immunity genes are involved. Other autoimmune diseases share the HLA gene link, which may be why people with type 1 are more likely to develop additional auto­immune disorders.
If you’re getting a good night’s rest but still find yourself so tired you can barely function, it’s definitely worth mentioning to your doctor. Diabetes often wreaks havoc on a person’s normal blood sugar levels, causing fatigue in the process. In later stages, the tissue death associated with untreated diabetes can also limit circulation, meaning oxygenated blood isn’t being effectively transported to your vital organs, making your body work harder and tiring you out along the way.
Medications used to treat diabetes do so by lowering blood sugar levels. There is broad consensus that when people with diabetes maintain tight glucose control (also called "tight glycemic control") -- keeping the glucose levels in their blood within normal ranges - that they experience fewer complications like kidney problems and eye problems.[84][85] There is however debate as to whether this is cost effective for people later in life.[86]
Diabetic ketoacidosis (DKA) is much less common than hypoglycemia but is potentially far more serious, creating a life-threatening medical emergency. [13] Ketosis usually does not occur when insulin is present. In the absence of insulin, however, severe hyperglycemia, dehydration, and ketone production contribute to the development of DKA. The most serious complication of DKA is the development of cerebral edema, which increases the risk of death and long-term morbidity. Very young children at the time of first diagnosis are most likely to develop cerebral edema.
Those dark patches on your skin could be more serious than a blotchy tan. In fact, they might be the first sign of diabetes. This darkening of the skin, which usually occurs on the hands and feet, in folds of skin, along the neck, and in a person’s groin and armpits, called acanthosis nigricans, often occurs when insulin levels are high. The high insulin levels in your blood can increase your body’s production of skin cells, many of which have increased pigmentation, giving skin a darkened appearance.

DKA usually follows increasing hyperglycemia and symptoms of osmotic diuresis. Users of insulin pumps, by virtue of absent reservoirs of subcutaneous insulin, may present with ketosis and more normal blood glucose levels. They are more likely to present with nausea, vomiting, and abdominal pain, symptoms similar to food poisoning. DKA may manifest as respiratory distress.


2. Home glucose monitoring using either a visually read test or a digital readout of the glucose concentration in a drop of blood. Patients can usually learn to use the necessary equipment and perform finger sticks. They keep a daily record of findings and are taught to adjust insulin dosage accordingly. More recent glucose monitoring devices can draw blood from other locations on the body, such as the forearm.
Stream a variety of exercise routines to get you moving and motivated! GlucoseZone™ is a digital exercise program that provides you with personalized exercise guidance and support designed to help you achieve the diabetes and fitness results you want. American Diabetes Association members receive an exclusive discount on their GlucoseZone subscription when they sign up using their ADA member ID!
Jump up ^ Santaguida PL, Balion C, Hunt D, Morrison K, Gerstein H, Raina P, Booker L, Yazdi H. "Diagnosis, Prognosis, and Treatment of Impaired Glucose Tolerance and Impaired Fasting Glucose". Summary of Evidence Report/Technology Assessment, No. 128. Agency for Healthcare Research and Quality. Archived from the original on 16 September 2008. Retrieved 20 July 2008.

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.


When it comes to diabetes, there's no real answer yet. Yes, science has begun to uncover the roots of this disease, unearthing a complex interplay of genes and environment—and a lot more unanswered questions. Meanwhile, there's plenty of misinformation to go around. (How often have you had to explain that diabetes doesn't happen because someone "ate too much"?)

2. Home glucose monitoring using either a visually read test or a digital readout of the glucose concentration in a drop of blood. Patients can usually learn to use the necessary equipment and perform finger sticks. They keep a daily record of findings and are taught to adjust insulin dosage accordingly. More recent glucose monitoring devices can draw blood from other locations on the body, such as the forearm.


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.
Diet and moderate exercise are the first treatments implemented in diabetes. For many Type II diabetics, weight loss may be an important goal in helping them to control their diabetes. A well-balanced, nutritious diet provides approximately 50-60% of calories from carbohydrates, approximately 10-20% of calories from protein, and less than 30% of calories from fat. The number of calories required by an individual depends on age, weight, and activity level. The calorie intake also needs to be distributed over the course of the entire day so surges of glucose entering the blood system are kept to a minimum.
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

Home blood sugar (glucose) testing is an important part of controlling blood sugar. One important goal of diabetes treatment is to keep the blood glucose levels near the normal range of 70 to 120 mg/dl before meals and under 140 mg/dl at two hours after eating. Blood glucose levels are usually tested before and after meals, and at bedtime. The blood sugar level is typically determined by pricking a fingertip with a lancing device and applying the blood to a glucose meter, which reads the value. There are many meters on the market, for example, Accu-Check Advantage, One Touch Ultra, Sure Step and Freestyle. Each meter has its own advantages and disadvantages (some use less blood, some have a larger digital readout, some take a shorter time to give you results, etc.). The test results are then used to help patients make adjustments in medications, diets, and physical activities.


Type 2 diabetes is the most common type of diabetes. It is a chronic problem in which blood glucose (sugar) can no longer be regulated. There are two reasons for this. First, the cells of the body become resistant to insulin (insulin resistant). Insulin works like a key to let glucose (blood sugar) move out of the blood and into the cells where it is used as fuel for energy. When the cells become insulin resistant, it requires more and more insulin to move sugar into the cells, and too much sugar stays in the blood. Over time, if the cells require more and more insulin, the pancreas can't make enough insulin to keep up and begins to fail.
As of 2016, 422 million people have diabetes worldwide,[101] up from an estimated 382 million people in 2013[17] and from 108 million in 1980.[101] Accounting for the shifting age structure of the global population, the prevalence of diabetes is 8.5% among adults, nearly double the rate of 4.7% in 1980.[101] Type 2 makes up about 90% of the cases.[16][18] Some data indicate rates are roughly equal in women and men,[18] but male excess in diabetes has been found in many populations with higher type 2 incidence, possibly due to sex-related differences in insulin sensitivity, consequences of obesity and regional body fat deposition, and other contributing factors such as high blood pressure, tobacco smoking, and alcohol intake.[102][103]
The major eye complication of diabetes is called diabetic retinopathy. Diabetic retinopathy occurs in patients who have had diabetes for at least five years. Diseased small blood vessels in the back of the eye cause the leakage of protein and blood in the retina. Disease in these blood vessels also causes the formation of small aneurysms (microaneurysms), and new but brittle blood vessels (neovascularization). Spontaneous bleeding from the new and brittle blood vessels can lead to retinal scarring and retinal detachment, thus impairing 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).
Periodontal Disease. Periodontal disease is a commonly observed dental problem for patients with diabetes. It is similar to the periodontal disease encountered among nondiabetic patients. However, as a consequence of the impaired immunity and healing associated with diabetes, it may be more severe and progress more rapidly (see Right). The potential for these changes points to the need for periodic professional evaluation and treatment.
Diabetes Forum App Find support, ask questions and share your experiences with 281,823 members of the diabetes community. Recipe App Delicious diabetes recipes, updated every Monday. Filter recipes by carbs, calories and time to cook. Low Carb Program Join 250,000 people on the award-winning education program for people with type 2 diabetes, prediabetes and obesity. Hypo Awareness Program The first comprehensive, free and open to all online step-by-step guide to improving hypo awareness. DiabetesPA Your diabetes personal assistant. Monitor every aspect of your diabetes. Simple, practical, free.
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.
There is an overall lack of public awareness of the signs and symptoms of type 1 diabetes. Making yourself aware of the signs and symptoms of type 1 diabetes is a great way to be proactive about your health and the health of your family members. If you notice any of these signs or symptoms, it’s possible that you have (or your child has) type 1 diabetes. A doctor can make that diagnosis by checking blood glucose levels.

Another form of diabetes called gestational diabetes can develop during pregnancy and generally resolves after the baby is delivered. This diabetic condition develops during the second or third trimester of pregnancy in about 2% of pregnancies. In 2004, incidence of gestational diabetes were reported to have increased 35% in 10 years. Children of women with gestational diabetes are more likely to be born prematurely, have hypoglycemia, or have severe jaundice at birth. The condition usually is treated by diet, however, insulin injections may be required. These women who have diabetes during pregnancy are at higher risk for developing Type II diabetes within 5-10 years.
Type 2 diabetes is typically a chronic disease associated with a ten-year-shorter life expectancy.[10] This is partly due to a number of complications with which it is associated, including: two to four times the risk of cardiovascular disease, including ischemic heart disease and stroke; a 20-fold increase in lower limb amputations, and increased rates of hospitalizations.[10] In the developed world, and increasingly elsewhere, type 2 diabetes is the largest cause of nontraumatic blindness and kidney failure.[24] It has also been associated with an increased risk of cognitive dysfunction and dementia through disease processes such as Alzheimer's disease and vascular dementia.[25] Other complications include acanthosis nigricans, sexual dysfunction, and frequent infections.[23]
The elderly diabetic person is at increased risk of atrial fibrillation (odds ratio: 1.4 for men and 1.6 for women)232 and at twofold increased risk of thromboembolism from atrial fibrillation.233,234 We can find no subgroup analysis of the major atrial fibrillation trials to examine the benefits of warfarin specifically in older diabetic subjects. It appears that the adverse event rate in diabetic people drops from 8.6 events per 100 patients per year to 2.8 events with warfarin use.234 It is important to check for retinal new vessels when diabetic subjects are placed on warfarin, although the Early Treatment Diabetic Retinopathy Study235 showed no excess vitreous or preretinal hemorrhages in subjects given aspirin for vascular prophylaxis.

Diabetes mellitus is a diagnostic term for a group of disorders characterized by abnormal glucose homeostasis resulting in elevated blood sugar. There is variability in its manifestations, wherein some individuals have only asymptomatic glucose intolerance, while others present acutely with diabetic ketoacidosis, and still others develop chronic complications such as nephropathy, neuropathy, retinopathy, or accelerated atherosclerosis. It is among the most common of chronic disorders, affecting up to 5–10% of the adult population of the Western world. Its prevalence varies over the globe, with certain populations, including some American Indian tribes and the inhabitants of Micronesia and Polynesia, having extremely high rates of diabetes (1,2). The prevalence of diabetes is increasing dramatically and it has been estimated that the worldwide prevalence will increase by more than 50% between the years 2000 and 2030 (3).
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]
Hemoglobin A1c or HbA1c is a protein on the surface of red blood cells. The HbA1c test is used to monitor blood sugar levels in people with type 1 and type 2 diabetes over time. Normal HbA1c levels are 6% or less. HbA1c levels can be affected by insulin use, fasting, glucose intake (oral or IV), or a combination of these and other factors. High hemoglobin A1c levels in the blood increases the risk of microvascular complications, for example, diabetic neuropathy, eye, and kidney disease.
×