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

Sasigarn A Bowden, MD Associate Professor of Pediatrics, Section of Pediatric Endocrinology, Metabolism and Diabetes, Department of Pediatrics, Ohio State University College of Medicine; Pediatric Endocrinologist, Associate Fellowship Program Director, Division of Endocrinology, Nationwide Children’s Hospital; Affiliate Faculty/Principal Investigator, Center for Clinical Translational Research, Research Institute at Nationwide Children’s Hospital
Keeping track of the number of calories provided by different foods can become complicated, so patients usually are advised to consult a nutritionist or dietitian. An individualized, easy to manage diet plan can be set up for each patient. Both the American Diabetes Association and the American Dietetic Association recommend diets based on the use of food exchange lists. Each food exchange contains a known amount of calories in the form of protein, fat, or carbohydrate. A patient's diet plan will consist of a certain number of exchanges from each food category (meat or protein, fruits, breads and starches, vegetables, and fats) to be eaten at meal times and as snacks. Patients have flexibility in choosing which foods they eat as long as they stick with the number of exchanges prescribed.
Type 1 diabetes has some connection to your family genes, but that doesn't mean you'll get it if one of your parents had it. "Since not all identical twins get diabetes, we do think that exposure to an additional environmental factor may trigger an immune response that ultimately causes destruction of the insulin-producing cells of the pancreas," says Dr. Sarah R. Rettinger, an endocrinologist with Providence Saint John's Health Center in Santa Monica, California.
Using insulin to get blood glucose levels to a healthy level is a good thing, not a bad one. For most people, type 2 diabetes is a progressive disease. When first diagnosed, many people with type 2 diabetes can keep their blood glucose at a healthy level with a combination of meal planning, physical activity, and taking oral medications. But over time, the body gradually produces less and less of its own insulin, and eventually oral medications may not be enough to keep blood glucose levels in a healthy range. 

This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings through its clearinghouses and education programs to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully reviewed by NIDDK scientists and other experts.

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.


A 2009 study shows how genetic information may shed light on the environment-gene interactions that lead to type 1. In the study, researchers found that one of the type 1 genes mediates the immune system's response to viruses. This finding supported the longtime hypothesis that a virus may somehow make the immune system attack the insulin-producing cells in the pancreas in people who are genetically susceptible to developing diabetes.
Weight loss surgery in those who are obese is an effective measure to treat diabetes.[101] Many are able to maintain normal blood sugar levels with little or no medication following surgery[102] and long-term mortality is decreased.[103] There however is some short-term mortality risk of less than 1% from the surgery.[104] The body mass index cutoffs for when surgery is appropriate are not yet clear.[103] It is recommended that this option be considered in those who are unable to get both their weight and blood sugar under control.[105][106]

The blood glucose levels may jump after people eat foods they did not realize were high in carbohydrates. Emotional stress, an infection, and many drugs tend to increase blood glucose levels. Blood glucose levels increase in many people in the early morning hours because of the normal release of hormones (growth hormone and cortisol), a reaction called the dawn phenomenon. Blood glucose may shoot too high if the body releases certain hormones in response to low blood glucose levels (Somogyi effect). Exercise may cause the levels of glucose in the blood to fall low.
Jump up ^ Piwernetz K, Home PD, Snorgaard O, Antsiferov M, Staehr-Johansen K, Krans M (May 1993). "Monitoring the targets of the St Vincent Declaration and the implementation of quality management in diabetes care: the DIABCARE initiative. The DIABCARE Monitoring Group of the St Vincent Declaration Steering Committee". Diabetic Medicine. 10 (4): 371–7. doi:10.1111/j.1464-5491.1993.tb00083.x. PMID 8508624.
If you are a diabetic and are pregnant you can have a normal, healthy pregnancy, but you need to take extra steps to avoid gaining excess weight and high blood sugars. Lifestyle habits (eating primarily vegetables and lean protein and exercising every day) will prevent problems during pregnancy. If you are a diabetic and become pregnant, monitor your blood sugar levels often. Talk with your doctor about exploring additional health care professionals, for example, a nutritionist, health coach, or naturopathic doctor about a healthy eating plan. If your blood sugar gets out of control you may:
Oral medications are available to lower blood glucose in Type II diabetics. In 1990, 23.4 outpatient prescriptions for oral antidiabetic agents were dispensed. By 2001, the number had increased to 91.8 million prescriptions. Oral antidiabetic agents accounted for more than $5 billion dollars in worldwide retail sales per year in the early twenty-first century and were the fastest-growing segment of diabetes drugs. The drugs first prescribed for Type II diabetes are in a class of compounds called sulfonylureas and include tolbutamide, tolazamide, acetohexamide, and chlorpropamide. Newer drugs in the same class are now available and include glyburide, glimeperide, and glipizide. How these drugs work is not well understood, however, they seem to stimulate cells of the pancreas to produce more insulin. New medications that are available to treat diabetes include metformin, acarbose, and troglitizone. The choice of medication depends in part on the individual patient profile. All drugs have side effects that may make them inappropriate for particular patients. Some for example, may stimulate weight gain or cause stomach irritation, so they may not be the best treatment for someone who is already overweight or who has stomach ulcers. Others, like metformin, have been shown to have positive effects such as reduced cardiovascular mortality, but but increased risk in other situations. While these medications are an important aspect of treatment for Type II diabetes, they are not a substitute for a well planned diet and moderate exercise. Oral medications have not been shown effective for Type I diabetes, in which the patient produces little or no insulin.
Dietary factors also influence the risk of developing type 2 DM. Consumption of sugar-sweetened drinks in excess is associated with an increased risk.[46][47] The type of fats in the diet is also important, with saturated fat and trans fats increasing the risk and polyunsaturated and monounsaturated fat decreasing the risk.[45] Eating lots of white rice, and other starches, also may increase the risk of diabetes.[48] A lack of physical activity is believed to cause 7% of cases.[49]
The protocol for therapy is determined by the type of diabetes; patients with either type 1 or type 2 must pay attention to their diet and exercise regimens. Insulin therapy may be prescribed for patients with type 2 diabetes as well as any who are dependent on insulin. In most cases, the type 2 diabetes patient can be treated effectively by reducing caloric intake, maintaining target weight, and promoting physical exercise.
As with many conditions, treatment of type 2 diabetes begins with lifestyle changes, particularly in your diet and exercise. If you have type 2 diabetes, speak to your doctor and diabetes educator about an appropriate diet. You may be referred to a dietitian. It is also a good idea to speak with your doctor before beginning an exercise program that is more vigourous than walking to determine how much and what kind of exercise is appropriate.
6. Polycystic ovary syndrome (PCOS): This is a common cause of female infertility and insulin resistance. It can cause signs and symptoms like irregular periods, acne, thinning scalp hair, and excess hair growth on the face and body. High insulin levels also increase the risk of developing diabetes, and about half of women with PCOS develop diabetes.
Visual impairment and blindness are common sequelae of uncontrolled diabetes. The three most frequently occurring problems involving the eye are diabetic retinopathy, cataracts, and glaucoma. photocoagulation of destructive lesions of the retina with laser beams can be used to delay further progress of pathologic changes and thereby preserve sight in the affected eye.

Exposure to certain viral infections (mumps and Coxsackie viruses) or other environmental toxins may serve to trigger abnormal antibody responses that cause damage to the pancreas cells where insulin is made. Some of the antibodies seen in type 1 diabetes include anti-islet cell antibodies, anti-insulin antibodies and anti-glutamic decarboxylase antibodies. These antibodies can be detected in the majority of patients, and may help determine which individuals are at risk for developing type 1 diabetes.
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. 

Jump up ^ Palmer, Suetonia C.; Mavridis, Dimitris; Nicolucci, Antonio; Johnson, David W.; Tonelli, Marcello; Craig, Jonathan C.; Maggo, Jasjot; Gray, Vanessa; De Berardis, Giorgia; Ruospo, Marinella; Natale, Patrizia; Saglimbene, Valeria; Badve, Sunil V.; Cho, Yeoungjee; Nadeau-Fredette, Annie-Claire; Burke, Michael; Faruque, Labib; Lloyd, Anita; Ahmad, Nasreen; Liu, Yuanchen; Tiv, Sophanny; Wiebe, Natasha; Strippoli, Giovanni F.M. (19 July 2016). "Comparison of Clinical Outcomes and Adverse Events Associated With Glucose-Lowering Drugs in Patients With Type 2 Diabetes". JAMA: the Journal of the American Medical Association. 316 (3): 313–24. doi:10.1001/jama.2016.9400. PMID 27434443.

Although age of onset and length of the disease process are related to the frequency with which vascular, renal, and neurologic complications develop, there are some patients who remain relatively free of sequelae even into the later years of their lives. Because diabetes mellitus is not a single disease but rather a complex constellation of syndromes, each patient has a unique response to the disease process.
Dietary factors also influence the risk of developing type 2 DM. Consumption of sugar-sweetened drinks in excess is associated with an increased risk.[46][47] The type of fats in the diet is also important, with saturated fat and trans fats increasing the risk and polyunsaturated and monounsaturated fat decreasing the risk.[45] Eating lots of white rice, and other starches, also may increase the risk of diabetes.[48] A lack of physical activity is believed to cause 7% of cases.[49]
There are a number of medications and other health problems that can predispose to diabetes.[39] Some of the medications include: glucocorticoids, thiazides, beta blockers, atypical antipsychotics,[40] and statins.[41] Those who have previously had gestational diabetes are at a higher risk of developing type 2 diabetes.[23] Other health problems that are associated include: acromegaly, Cushing's syndrome, hyperthyroidism, pheochromocytoma, and certain cancers such as glucagonomas.[39] Testosterone deficiency is also associated with type 2 diabetes.[42][43]
When you have diabetes, excess sugar (glucose) builds up in your blood. Your kidneys are forced to work overtime to filter and absorb the excess sugar. If your kidneys can't keep up, the excess sugar is excreted into your urine, dragging along fluids from your tissues. This triggers more frequent urination, which may leave you dehydrated. As you drink more fluids to quench your thirst, you'll urinate even more.

Doctors can also measure the level of a protein, hemoglobin A1C (also called glycosylated or glycolated hemoglobin), in the blood. Hemoglobin is the red, oxygen-carrying substance in red blood cells. When blood is exposed to high blood glucose levels over a period of time, glucose attaches to the hemoglobin and forms glycosylated hemoglobin. The hemoglobin A1C level (reported as the percentage of hemoglobin that is A1C) reflects long-term trends in blood glucose levels rather than rapid changes.


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.
Family or personal history. Your risk increases if you have prediabetes — a precursor to type 2 diabetes — or if a close family member, such as a parent or sibling, has type 2 diabetes. You're also at greater risk if you had gestational diabetes during a previous pregnancy, if you delivered a very large baby or if you had an unexplained stillbirth.
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