Scientists have done studies of twins to help estimate how important genes are in determining one's risk of developing diabetes. Identical twins have identical genes and thus the same genetic risk for a disease. Research has found that if one identical twin has type 1 diabetes, the chance that the other twin will get the disease is roughly 40 or 50 percent. For type 2 diabetes, that risk goes up to about 80 or 90 percent. This might suggest that genes play a bigger role in type 2 than in type 1, but that isn't necessarily so. Type 2 is far more common in the general population than type 1, which means that regardless of genetics both twins are more likely to develop type 2 diabetes.
Risk factors for type 2 diabetes include obesity, high cholesterol, high blood pressure, and physical inactivity. The risk of developing type 2 diabetes also increases as people grow older. People who are over 40 and overweight are more likely to develop type 2 diabetes, although the incidence of this type of diabetes in adolescents is growing. Diabetes is more common among Native Americans, African Americans, Hispanic Americans and Asian Americans/Pacific Islanders. Also, people who develop diabetes while pregnant (a condition called gestational diabetes) are more likely to develop type 2 diabetes later in life.
A healthy lifestyle can prevent almost all cases of type 2 diabetes. A large research study called the Diabetes Prevention Program, found that patients who made intensive changes including diet and exercise, reduced their risk of developing diabetes by 58%. Patients who were over 60 years old seemed to experience extra benefit; they reduced their risk by 71%. In comparison, patients who were given the drug metformin for prevention only reduced their risk by 31%.
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.
Diabetes is a disease in which your blood glucose, or blood sugar, levels are too high. Glucose comes from the foods you eat. Insulin is a hormone that helps the glucose get into your cells to give them energy. With type 1 diabetes, your body does not make insulin. With type 2 diabetes, the more common type, your body does not make or use insulin well. Without enough insulin, the glucose stays in your blood.
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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.
There are a range of different symptoms in people with diabetes. They may feel thirsty, pass a large amount of urine, wake up overnight to pass urine, lose weight and have blurred vision. Patients are vulnerable to infections such as thrush and may present with this. Particularly in type 2 diabetes, patients may not be aware of their diabetes for several years and a diagnosis may only be made when they seek treatment for diabetes-related complications such as foot, eye or kidney problems. Some patients may become severely ill and be taken into hospital with an infection and/or very high blood sugar levels.
About 40% of diabetes sufferers require oral agents for satisfactory blood glucose control, and some 40% need insulin injections. This hormone was isolated by Frederic Banting and Charles Best in 1921 in Canada. It revolutionized the treatment of diabetes and prevention of its complications, transforming Type 1 diabetes from a fatal disease to one in which long-term survival became achievable.

In people with type 1 diabetes, the symptoms often begin abruptly and dramatically. A serious condition called diabetic ketoacidosis, a complication in which the body produces excess acid, may quickly develop. In addition to the usual diabetes symptoms of excessive thirst and urination, the initial symptoms of diabetic ketoacidosis also include nausea, vomiting, fatigue, and—particularly in children—abdominal pain. Breathing tends to become deep and rapid as the body attempts to correct the blood’s acidity (see Acidosis), and the breath smells fruity and like nail polish remover. Without treatment, diabetic ketoacidosis can progress to coma and death, sometimes very quickly.
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).

Diabetes is a chronic condition, and it can last an entire lifetime. The goal of treating diabetes is to keep blood glucose levels as close to a normal range as possible. This prevents the symptoms of diabetes and the long-term complications of the condition. If you've been diagnosed with diabetes, your doctor – working with the members of your diabetes care team – will help you find your target blood glucose levels.
The food that people eat provides the body with glucose, which is used by the cells as a source of energy. If insulin isn't available or doesn't work correctly to move glucose from the blood into cells, glucose will stay in the blood. High blood glucose levels are toxic, and cells that don't get glucose are lacking the fuel they need to function properly.

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.
There are many types of sugar. Some sugars are simple, and others are complex. Table sugar (sucrose) is made of two simpler sugars called glucose and fructose. Milk sugar (lactose) is made of glucose and a simple sugar called galactose. The carbohydrates in starches, such as bread, pasta, rice, and similar foods, are long chains of different simple sugar molecules. Sucrose, lactose, carbohydrates, and other complex sugars must be broken down into simple sugars by enzymes in the digestive tract before the body can absorb them.
People with diabetes aim for a hemoglobin A1C level of less than 7%. Achieving this level is difficult, but the lower the hemoglobin A1C level, the less likely people are to have complications. Doctors may recommend a slightly higher or lower target for certain people depending on their particular health situation. However, levels above 9% show poor control, and levels above 12% show very poor control. Most doctors who specialize in diabetes care recommend that hemoglobin A1C be measured every 3 to 6 months.
ORAL GLUCOSE TOLERANCE TEST. Blood samples are taken from a vein before and after a patient drinks a thick, sweet syrup of glucose and other sugars. In a non-diabetic, the level of glucose in the blood goes up immediately after the drink and then decreases gradually as insulin is used by the body to metabolize, or absorb, the sugar. In a diabetic, the glucose in the blood goes up and stays high after drinking the sweetened liquid. A plasma glucose level of 11.1 mmol/L (200 mg/dL) or higher at two hours after drinking the syrup and at one other point during the two-hour test period confirms the diagnosis of diabetes.
The blood vessels and blood are the highways that transport sugar from where it is either taken in (the stomach) or manufactured (in the liver) to the cells where it is used (muscles) or where it is stored (fat). Sugar cannot go into the cells by itself. The pancreas releases insulin into the blood, which serves as the helper, or the "key," that lets sugar into the cells for use as energy.

When the glucose concentration in the blood remains high over time, the kidneys will reach a threshold of reabsorption, and glucose will be excreted in the urine (glycosuria).[62] This increases the osmotic pressure of the urine and inhibits reabsorption of water by the kidney, resulting in increased urine production (polyuria) and increased fluid loss. Lost blood volume will be replaced osmotically from water held in body cells and other body compartments, causing dehydration and increased thirst (polydipsia).[60]
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A fingerstick glucose test is most often used to monitor blood glucose. Most blood glucose monitoring devices (glucose meters) use a drop of blood obtained by pricking the tip of the finger with a small lancet. The lancet holds a tiny needle that can be jabbed into the finger or placed in a spring-loaded device that easily and quickly pierces the skin. Most people find that the pricking causes only minimal discomfort. Then, a drop of blood is placed on a reagent strip. The strip contains chemicals that undergo changes depending on the glucose level. The glucose meter reads the changes in the test strip and reports the result on a digital display. Some devices allow the blood sample to be obtained from other sites, such as the palm, forearm, upper arm, thigh, or calf. Home glucose meters are smaller than a deck of cards.
Diabetes mellitus (DM) is a strong predictor of cardiovascular morbidity and mortality and is associated with both micro- and macrovascular complications.1 Cardiovascular disease (CVD) causes up to 70% of all deaths in people with DM. The epidemic of DM will thus be followed by a burden of diabetes-related vascular diseases. The number of DM patients increases with aging of the population, in part because of the increasing prevalence of obesity and sedentary lifestyle. Although the mortality from coronary artery disease (CAD) in patients without DM has declined since the 1990s, the mortality in men with type 2 diabetes (T2DM) has not changed significantly.2 Moreover, DM is an independent risk factor for heart failure. Heart failure is closely related to diabetic cardiomyopathy: changes in the structure and function of the myocardium are not directly linked to CAD or hypertension. Diabetic cardiomyopathy is clinically characterized by an initial increase in left ventricular stiffness and subclinical diastolic dysfunction, gradually compromising left ventricular systolic function with loss of contractile function and progress into overt congestive heart failure. DM accounts for a significant percentage of patients with a diagnosis of heart failure in epidemiologic studies such as the Framingham Study and the UK Prospective Diabetes Study (UKPDS).2 A 1% increase in glycated hemoglobin (HbA1c) correlates to an increment of 8% in heart failure.3 The prevalence of heart failure in elderly diabetic patients is up to 30%.3
Diabetic neuropathy is probably the most common complication of diabetes. Studies suggest that up to 50% of people with diabetes are affected to some degree. Major risk factors of this condition are the level and duration of elevated blood glucose. Neuropathy can lead to sensory loss and damage to the limbs. It is also a major cause of impotence in diabetic men.
Jump up ^ Feinman, RD; Pogozelski, WK; Astrup, A; Bernstein, RK; Fine, EJ; Westman, EC; Accurso, A; Frassetto, L; Gower, BA; McFarlane, SI; Nielsen, JV; Krarup, T; Saslow, L; Roth, KS; Vernon, MC; Volek, JS; Wilshire, GB; Dahlqvist, A; Sundberg, R; Childers, A; Morrison, K; Manninen, AH; Dashti, HM; Wood, RJ; Wortman, J; Worm, N (January 2015). "Dietary carbohydrate restriction as the first approach in diabetes management: critical review and evidence base". Nutrition. Burbank, Los Angeles County, Calif. 31 (1): 1–13. doi:10.1016/j.nut.2014.06.011. PMID 25287761.
Another less common form is gestational diabetes, a temporary condition that occurs during pregnancy. Depending on risk factors, between 3% to 13% of Canadian women will develop gestational diabetes which can be harmful for the baby if not controlled. The problem usually clears up after delivery, but women who have had gestational diabetes have a higher risk of developing type 2 diabetes later in life.
Janis McWilliams, RN, MSN, CDE, BC-ADM, responds: Yes, in type 1 diabetes in particular, the onset of symptoms like frequent urination and extreme thirst can be very sudden. In type 2 diabetes, the symptoms tend to come about more gradually, and sometimes there are no signs at all. People who have symptoms should contact their health care provider immediately for an accurate diagnosis. Keep in mind that these symptoms could signal other problems, too.

These diabetes complications are related to blood vessel diseases and are generally classified into small vessel disease, such as those involving the eyes, kidneys and nerves (microvascular disease), and large vessel disease involving the heart and blood vessels (macrovascular disease). Diabetes accelerates hardening of the arteries (atherosclerosis) of the larger blood vessels, leading to coronary heart disease (angina or heart attack), strokes, and pain in the lower extremities because of lack of blood supply (claudication).
Endocrinology is the specialty of medicine that deals with hormone disturbances, and both endocrinologists and pediatric endocrinologists manage patients with diabetes. People with diabetes may also be treated by family medicine or internal medicine specialists. When complications arise, people with diabetes may be treated by other specialists, including neurologists, gastroenterologists, ophthalmologists, surgeons, cardiologists, or others.
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.
From a dental perspective, pregnancy leads to hormonal changes that increase the mother’s risk of developing gingivitis and gingival lesions called pregnancy tumors (see Right). Not surprisingly, poor glycemic control further adds to this risk. Therefore, it is imperative that if you become pregnant, you should promptly see your dentist. He or she will work with you to ensure that your dental self-care regimen is maximized to prevent or control your dental disease. Additional Resources on Diabetes and Oral Health National Institute of Dental and Craniofacial Research www.nidcr.nih.gov American Diabetes Association www.diabetes.org American Dental Association www.dental.org American Academy of Periodontology www.perio.org The Diabetes Monitor www.diabetesmonitor.com David Mendosa www.mendosa.com Diatribe www.diatribe.us 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 to: a b 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. 13 (41): 1–190, 215–357, iii–iv. doi:10.3310/hta13410. PMID 19726018.
Most people with diabetes should keep a record of their blood glucose levels and report them to their doctor or nurse for advice in adjusting the dose of insulin or the oral antihyperglycemic drug. Many people can learn to adjust the insulin dose on their own as necessary. Some people who have mild or early type 2 diabetes that is well-controlled with one or two drugs may be able to monitor their fingerstick glucose levels relatively infrequently.
Despite our efforts, patients are still likely to suffer myocardial infarction. The Diabetes mellitus, Insulin Glucose infusion in Acute Myocardial Infarction (DIGAMI) study236,237 reported on treating subjects with acute myocardial infarction and either diabetes or raised random plasma glucose (i.e., not necessarily diabetic) with either an intensive insulin infusion and then a four-times daily insulin regimen or conventional treatment. Over a mean follow-up of 3.4 years, there was a 33% death rate in the treatment group compared with a 44% death rate in the control group, an absolute reduction in mortality of 11%. The effect was greatest among the subgroup without previous insulin treatment and at a low cardiovascular risk. Evidence is continuing to accumulate that the diabetic person should have a glucose/insulin infusion after a myocardial infarction.
Keep your immunizations up to date. High blood sugar can weaken your immune system. Get a flu shot every year, and your doctor will likely recommend the pneumonia vaccine, as well. The Centers for Disease Control and Prevention (CDC) also recommends the hepatitis B vaccination if you haven't previously received this vaccine and you're an adult age 19 to 59 with type 1 or type 2 diabetes. The CDC advises vaccination as soon as possible after diagnosis with type 1 or type 2 diabetes. If you are age 60 or older, have diabetes and haven't previously received the vaccine, talk to your doctor about whether it's right for you.
According to the Mayo Clinic, your risk of developing type 2 diabetes increases as you age. Your risk goes up after age 45 in particular. However, the incidence of type 2 diabetes is increasing dramatically among children, adolescents, and younger adults. Likely factors include reduced exercise, decreased muscle mass, and weight gain as you age. Type 1 diabetes is usually diagnosed by the age of 30.
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.

Of course, you’re exhausted every now and then. But ongoing fatigue is an important symptom to pay attention to; it might mean the food you’re eating for energy isn’t being broken down and used by cells as it’s supposed to. “You’re not getting the fuel your body needs,” says Dobbins. “You’re going to be tired and feel sluggish.” But in many cases of type 2 diabetes, your sugar levels can be elevated for awhile, so these diabetes symptoms could come on slowly.
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.
People with type 1 diabetes sometimes receive transplantation of an entire pancreas or of only the insulin-producing cells from a donor pancreas. This procedure may allow people with type 1 diabetes mellitus to maintain normal glucose levels. However, because immunosuppressant drugs must be given to prevent the body from rejecting the transplanted cells, pancreas transplantation is usually done only in people who have serious complications due to diabetes or who are receiving another transplanted organ (such as a kidney) and will require immunosuppressant drugs anyway.

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.

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.
Type 1 diabetes occurs because the insulin-producing cells of the pancreas (beta cells) are damaged. In type 1 diabetes, the pancreas makes little or no insulin, so sugar cannot get into the body's cells for use as energy. People with type 1 diabetes must use insulin injections to control their blood glucose. Type 1 is the most common form of diabetes in people who are under age 30, but it can occur at any age. Ten percent of people with diabetes are diagnosed with type 1.

Dr. May currently works as a fulltime endocrinologist and has been in private practice since 2004. He has a variety of interests, predominantly obesity and diabetes, but also sees patients with osteoporosis, thyroid disorders, men's health disorders, pituitary and adrenal disorders, polycystic ovaries, and disorders of growth. He is a leading member of several obesity and diabetes societies and runs a trial centre for new drugs.

Diabetes mellitus has been recorded in all species but is most commonly seen in middle-aged to older, obese, female dogs. A familial predisposition has been suggested. It is possible to identify two types of diabetes, corresponding to the disease in humans, depending on the response to an intravenous glucose tolerance test. Type I is insulin-dependent and comparable to the juvenile onset form of the disease in children in which there is an absolute deficiency of insulin—there is a very low initial blood insulin level and a low response to the injected glucose. This form is seen in a number of dog breeds, particularly the Keeshond, Doberman pinscher, German shepherd dog, Poodle, Golden retriever and Labrador retriever.
Patients with type 1 DM, unless they have had a pancreatic transplant, require insulin to live; intensive therapy with insulin to limit hyperglycemia (“tight control”) is more effective than conventional therapy in preventing the progression of serious microvascular complications such as kidney and retinal diseases. Intensive therapy consists of three or more doses of insulin injected or administered by infusion pump daily, with frequent self-monitoring of blood glucose levels as well as frequent changes in therapy as a result of contacts with health care professionals. Some negative aspects of intensive therapy include a three times more frequent occurrence of severe hypoglycemia, weight gain, and an adverse effect on serum lipid levels, i.e., a rise in total cholesterol, LDL cholesterol, and triglycerides and a fall in HDL cholesterol. Participation in an intensive therapy program requires a motivated patient, but it can dramatically reduce eye, nerve, and renal complications compared to conventional therapy. See: insulin pump for illus.
Rosiglitazone, a thiazolidinedione, has not been found to improve long-term outcomes even though it improves blood sugar levels.[93] Additionally it is associated with increased rates of heart disease and death.[94] Angiotensin-converting enzyme inhibitors (ACEIs) prevent kidney disease and improve outcomes in those with diabetes.[95][96] The similar medications angiotensin receptor blockers (ARBs) do not.[96] A 2016 review recommended treating to a systolic blood pressure of 140 to 150 mmHg.[97]
n a metabolic disorder caused primarily by a defect in the production of insulin by the islet cells of the pancreas, resulting in an inability to use carbohydrates. Characterized by hyperglycemia, glycosuria, polyuria, hyperlipemia (caused by imperfect catabolism of fats), acidosis, ketonuria, and a lowered resistance to infection. Periodontal manifestations if blood sugar is not being controlled may include recurrent and multiple periodontal abscesses, osteoporotic changes in alveolar bone, fungating masses of granulation tissue protruding from periodontal pockets, a lowered resistance to infection, and delay in healing after periodontal therapy. See also blood glucose level(s).
diabetes mel´litus a broadly applied term used to denote a complex group of syndromes that have in common a disturbance in the oxidation and utilization of glucose, which may be secondary to a malfunction of the beta cells of the pancreas, whose function is the production and release of insulin. Because insulin is involved in the metabolism of carbohydrates, proteins, and fats, diabetes is not limited to a disturbance of glucose homeostasis alone. Insulin resistance may also sometimes play a role in the etiology of diabetes. 
People with type 1 diabetes and certain people with type 2 diabetes may use carbohydrate counting or the carbohydrate exchange system to match their insulin dose to the carbohydrate content of their meal. "Counting" the amount of carbohydrate in a meal is used to calculate the amount of insulin the person takes before eating. However, the carbohydrate-to-insulin ratio (the amount of insulin taken for each gram of carbohydrate in the meal) varies for each person, and people with diabetes need to work closely with a dietician who has experience in working with people with diabetes to master the technique. Some experts have advised use of the glycemic index (a measure of the impact of an ingested carbohydrate-containing food on the blood glucose level) to delineate between rapid and slowly metabolized carbohydrates, although there is little evidence to support this approach.

gestational diabetes diabetes mellitus with onset or first recognition during pregnancy, usually during the second or third trimester. In some cases mild, undetected glucose intolerance was present before pregnancy. It often disappears after the end of the pregnancy, but many women with this condition develop permanent diabetes mellitus in later life. Although the disordered carbohydrate metabolism is usually mild, prompt detection and treatment are necessary to avoid fetal and neonatal morbidity and mortality.


Low testosterone (low-T) can be caused by conditions such as type 2 diabetes, obesity, liver or kidney disease, hormonal disorders, certain infections, and hypogonadism. Signs and symptoms that a person may have low-T include insomnia, increased body fat, weight gain, reduced muscle, infertility, decreased sex drive, depression, and worsening of congestive heart failure or sleep apnea.
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