Beta cells are vulnerable to more than just bad genes, which may explain the associations between type 2 diabetes and environmental factors that aren't related to how much fat a body has or where it is stored. Beta cells carry vitamin D receptors on their surface, and people with vitamin D deficiency are at increased risk for type 2. Plus, several studies have shown that people with higher levels of toxic substances in their blood—such as from the PCBs found in fish fat—are at increased risk of type 2 diabetes, though a cause-and-effect relationship hasn't been proved. (Toxic substances and vitamin D have also been implicated in type 1 diabetes, but the disease mechanism may be unrelated to what's going on in type 2.)


Recently, battery-operated insulin pumps have been developed that can be programmed to mimic normal insulin secretion more closely. A person wearing an insulin pump still must monitor blood sugar several times a day and adjust the dosage, and not all diabetic patients are motivated or suited to such vigilance. It is hoped that in the future an implantable or external pump system may be perfected, containing a glucose sensor. In response to data from the sensor the pump will automatically deliver insulin according to changing levels of blood glucose.
Diabetes mellitus is a condition in which the body does not produce enough of the hormone insulin, resulting in high levels of sugar in the bloodstream. There are many different types of diabetes; the most common are type 1 and type 2 diabetes, which are covered in this article. Gestational diabetes occurs during the second half of pregnancy and is covered in a separate article. Diabetes can also be caused by disease or damage to the pancreas, Cushing's syndrome, acromegaly and there are also some rare genetic forms.
Diabetes can be hard enough as it is, so do what you can to make life with it less complicated. For example, you don't have to be a master chef to put together a healthy meal. You can use ingredients that are right in your home. If you find your medication regimen to be too complex or too expensive, request that your physician change it. If you continue to forget to take your medicines, find simple ways to help you take them, like setting a reminder on your cell phone.
Diabetes was one of the first diseases described,[107] with an Egyptian manuscript from c. 1500 BCE mentioning "too great emptying of the urine".[108] The Ebers papyrus includes a recommendation for a drink to be taken in such cases.[109] The first described cases are believed to be of type 1 diabetes.[108] Indian physicians around the same time identified the disease and classified it as madhumeha or "honey urine", noting the urine would attract ants.[108][109]
With type 1, a disease that often seems to strike suddenly and unexpectedly, the effects of environment and lifestyle are far less clear. But several theories attempt to explain why cases of type 1 have increased so dramatically in recent decades, by around 5 percent per year since 1980. The three main suspects now are too little sun, too good hygiene, and too much cow's milk.

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]
We give you special kudos for managing your condition, as it is not always easy. If you've had diabetes for a long time, it's normal to burn out sometimes. You may get tired of your day to day tasks, such as counting carbohydrates or measuring your blood sugar. Lean on a loved one or a friend for support, or consider talking to someone else who has diabetes who can provide, perhaps, an even more understanding ear or ideas that can help you.
Jump up ^ Sarwar N, Gao P, Seshasai SR, Gobin R, Kaptoge S, Di Angelantonio E, Ingelsson E, Lawlor DA, Selvin E, Stampfer M, Stehouwer CD, Lewington S, Pennells L, Thompson A, Sattar N, White IR, Ray KK, Danesh J (June 2010). "Diabetes mellitus, fasting blood glucose concentration, and risk of vascular disease: a collaborative meta-analysis of 102 prospective studies". Lancet. 375 (9733): 2215–22. doi:10.1016/S0140-6736(10)60484-9. PMC 2904878. PMID 20609967.

Diabetes mellitus occurs throughout the world but is more common (especially type 2) in more developed countries. The greatest increase in rates has however been seen in low- and middle-income countries,[101] where more than 80% of diabetic deaths occur.[105] The fastest prevalence increase is expected to occur in Asia and Africa, where most people with diabetes will probably live in 2030.[106] The increase in rates in developing countries follows the trend of urbanization and lifestyle changes, including increasingly sedentary lifestyles, less physically demanding work and the global nutrition transition, marked by increased intake of foods that are high energy-dense but nutrient-poor (often high in sugar and saturated fats, sometimes referred to as the "Western-style" diet).[101][106] The global prevalence of diabetes might increase by 55% between 2013 and 2035.[101]


Diabetes mellitus is a chronic disease caused by inherited and/or acquired deficiency in production of insulin by the pancreas, or by the ineffectiveness of the insulin produced. Such a deficiency results in increased concentrations of glucose in the blood, which in turn damage many of the body's systems, in particular the blood vessels and nerves.
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.
Your risk for Type 2 diabetes increases as you get older. It also increases if you smoke. Although smoking doesn't cause diabetes per se, the negative effects on your health are enough to make it more likely that Type 2 diabetes will occur if you have the other risk factors. "We try to be aggressive with smoking cessation, in particular in patients with diabetes," says Dr. Asha M. Thomas, an endocrinologist with Sinai Hospital of Baltimore.
Brittle diabetics are a subgroup of Type I where patients have frequent and rapid swings of blood sugar levels between hyperglycemia (a condition where there is too much glucose or sugar in the blood) and hypoglycemia (a condition where there are abnormally low levels of glucose or sugar in the blood). These patients may require several injections of different types of insulin during the day to keep the blood sugar level within a fairly normal range.
Other potentially important mechanisms associated with type 2 diabetes and insulin resistance include: increased breakdown of lipids within fat cells, resistance to and lack of incretin, high glucagon levels in the blood, increased retention of salt and water by the kidneys, and inappropriate regulation of metabolism by the central nervous system.[10] However, not all people with insulin resistance develop diabetes, since an impairment of insulin secretion by pancreatic beta cells is also required.[13]
The glucose level at which symptoms develop varies greatly from individual to individual (and from time to time in the same individual), depending in part on the duration of diabetes, the frequency of hypoglycemic episodes, the rate of fall of glycemia, and overall control. (Glucose is also the sole energy source for erythrocytes and the kidney medulla.)
There is no single gene that “causes” type 1 diabetes. Instead, there are a large number of inherited factors that may increase an individual’s likelihood of developing diabetes. This is known as multifactorial inheritance. The genes implicated in the development of type 1 diabetes mellitus control the human leukocyte antigen (HLA) system. This system is involved in the complex process of identifying cells which are a normal part of the body, and distinguishing them from foreign cells, such as those of bacteria or viruses. In an autoimmune disease such as diabetes mellitus, this system makes a mistake in identifying the normal ‘self’ cells as ‘foreign’, and attacks the body.  

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.
Type 2 diabetes is partly preventable by staying a normal weight, exercising regularly, and eating properly.[1] Treatment involves exercise and dietary changes.[1] If blood sugar levels are not adequately lowered, the medication metformin is typically recommended.[7][14] Many people may eventually also require insulin injections.[9] In those on insulin, routinely checking blood sugar levels is advised; however, this may not be needed in those taking pills.[15] Bariatric surgery often improves diabetes in those who are obese.[8][16]

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.
Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Poorly controlled diabetic patients are at risk for numerous oral complications such as periodontal disease, salivary gland dysfunction, infection, neuropathy, and poor healing. None of these complications are unique to diabetes. However, their presence may serve as an early clue to the possible presence of diabetes, prompting your dentist to perform or request further testing.
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.
According to the National Institutes of Health, the reported rate of gestational diabetes is between 2% to 10% of pregnancies. Gestational diabetes usually resolves itself after pregnancy. Having gestational diabetes does, however, put mothers at risk for developing type 2 diabetes later in life. Up to 10% of women with gestational diabetes develop type 2 diabetes. It can occur anywhere from a few weeks after delivery to months or years later.
Does having type 2 diabetes affect life expectancy? While continued improvements in therapies and care for type 2 diabetes may be helping patients live longer, the unfortunate reality is that type 2 diabetes has been shown to decrease life expectancy by up to ten years, according to Diabetes UK. There is still much to be done to ensure that all patients have access to appropriate healthcare and treatments to live a happier and healthier life with type 2 diabetes.
No single environmental trigger has been identified as causing diabetes mellitus, however both infectious agents and dietary factors are thought to be important. Various viruses have been implicated in the development of type I DM. They may act by initiating or modifying the autoimmune process. In particular, the rubella virus and coxsackie viruses have been closely studied. In particular, congenital rubella infection has shown direct relationships with the development of type 1 diabetes mellitus. This is presumably due to the virus (or antibodies against it) damaging the beta cells of the pancreas. Some research has looked at dietary factors that may be associated with type 1 diabetes. In particular, cow’s milk proteins (such as bovine serum albumin) which may have some similarities to pancreatic islet cell markers may be able to trigger the autoimmune process. Other chemicals including nitrosamines have been identified as causes of diabetes mellitus in animal models, but not in humans.
Can type 2 diabetes be prevented? It is possible to reduce the risk of developing type 2 diabetes, although the underlying risk of type 2 diabetes depends strongly on genetic factors. But there was less type 2 diabetes around some years ago when people had a more active life and didn’t eat a modern Western diet. So it is fair to say that risk of getting type 2 diabetes is based on a genetic predisposition that is aggravated by lifestyle. Type 2 diabetes is associated with obesity, as well as a variety of environmental factors. To lower the risk of developing type 2 diabetes (as well as other diseases), it is highly recommended to exercise often, eat healthily, and maintain a healthy weight. 
Type 2 diabetes primarily occurs as a result of obesity and lack of exercise.[1] Some people are more genetically at risk than others.[6] Type 2 diabetes makes up about 90% of cases of diabetes, with the other 10% due primarily to diabetes mellitus type 1 and gestational diabetes.[1] In diabetes mellitus type 1 there is a lower total level of insulin to control blood glucose, due to an autoimmune induced loss of insulin-producing beta cells in the pancreas.[12][13] Diagnosis of diabetes is by blood tests such as fasting plasma glucose, oral glucose tolerance test, or glycated hemoglobin (A1C).[3]
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.
The term "diabetes" or "to pass through" was first used in 230 BCE by the Greek Apollonius of Memphis.[108] The disease was considered rare during the time of the Roman empire, with Galen commenting he had only seen two cases during his career.[108] This is possibly due to the diet and lifestyle of the ancients, or because the clinical symptoms were observed during the advanced stage of the disease. Galen named the disease "diarrhea of the urine" (diarrhea urinosa).[110]

Insulin Therapy. Exogenous insulin is given to patients with diabetes mellitus as a supplement to the insufficient amount of endogenous insulin that they produce. In some cases, this must make up for an absolute lack of insulin from the pancreas. Exogenous insulin is available in various types. It must be given by injection, usually subcutaneously, and because it is a potent drug, the dosage must be measured meticulously. Commonly, regular insulin, which is a fast-acting insulin with a short span of action, is mixed with one of the longer-acting insulins and both types are administered in one injection.
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]
Patients with type 2 diabetes can still make insulin, but not enough to control their glucose levels. Type 2 diabetes is therefore initially treated with a combination of lifestyle changes (diet and exercise) which reduce the need for insulin and therefore lower glucose levels. If this is insufficient to achieve good glucose control, a range of tablets are available. These include metformin and pioglitazone, which, like diet and exercise, reduce insulin requirements; sulphonylureas (e.g. gliclazide), which stimulate insulin secretion; DPP4 inhibitors (e.g sitagliptin) and GLP-1 agonists (e.g. liraglutide), which stimulate insulin production and reduce appetite; and SGLT2 inhibitors (e.g. dapagliflozin), which lower blood sugar levels by causing sugar to pass out of the body in the urine. In many patients, particularly after several years of treatment, insulin production is so low or so insufficient compared with the patient's needs that patients with type 2 diabetes have to be treated with insulin injections, either alone or in combination with tablets.

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.


The glucose level at which symptoms develop varies greatly from individual to individual (and from time to time in the same individual), depending in part on the duration of diabetes, the frequency of hypoglycemic episodes, the rate of fall of glycemia, and overall control. (Glucose is also the sole energy source for erythrocytes and the kidney medulla.)
Being too heavy gets the bulk of the blame for triggering type 2 diabetes. According to the National Institutes of Health, about 85 percent of people with type 2 diabetes are overweight or obese. But consider that the remaining 15 percent are not. Consider, too, that roughly two-thirds of overweight people and a third of those who are obese will never develop diabetes. In other words, normal-weight and thin people also develop type 2, while heavy people won't necessarily. Clearly, there is more to the connection between lifestyle and type 2 diabetes than just body size.
Jump up ^ Pignone M, Alberts MJ, Colwell JA, Cushman M, Inzucchi SE, Mukherjee D, Rosenson RS, Williams CD, Wilson PW, Kirkman MS (June 2010). "Aspirin for primary prevention of cardiovascular events in people with diabetes: a position statement of the American Diabetes Association, a scientific statement of the American Heart Association, and an expert consensus document of the American College of Cardiology Foundation". Diabetes Care. 33 (6): 1395–402. doi:10.2337/dc10-0555. PMC 2875463. PMID 20508233.
The above tips are important for you. But it's also crucial to allow yourself time to cope with the diagnosis and commit to making lifestyle changes that will benefit you forever. The good news is the diabetes is a manageable disease; the tough part is that you must think about it daily. Consider finding support—someone that you can talk to about your struggles—be that a friend, another person with diabetes, or a loved one. This may seem trivial, but it truly can help you take control of diabetes so that it doesn't control you. Some next steps that may help you to get on the right track at this early stage in your journey:
Type 2 diabetes is usually associated with being overweight (BMI greater than 25), and is harder to control when food choices are not adjusted, and you get no physical activity. And while it’s true that too much body fat and physical inactivity (being sedentary) does increase the likelihood of developing type 2, even people who are fit and trim can develop this type of diabetes.2,3
Watch for thirst or a very dry mouth, frequent urination, vomiting, shortness of breath, fatigue and fruity-smelling breath. You can check your urine for excess ketones with an over-the-counter ketones test kit. If you have excess ketones in your urine, consult your doctor right away or seek emergency care. This condition is more common in people with type 1 diabetes but can sometimes occur in people with type 2 diabetes.
It’s not uncommon for patients to suddenly feel unsteady and immediately need to reach for carbs, says Marjorie Cypress, a nurse practitioner at an endocrinology clinic in Albuquerque, New Mexico, and 2014 president of health care and education for the American Diabetes Association. “When you have high blood sugar, your body has a problem regulating its glucose,” she explains. “If you’ve eaten something high in carbohydrates, your body shoots out a little too much insulin, and your glucose drops quickly. This makes you feel shaky, and you tend to crave carbs or sugar. This can lead to a vicious cycle.” These are the best foods for someone on a diabetic diet.
Diabetes: The differences between types 1 and 2 There are fundamental differences between diabetes type 1 and type 2, including when they might occur, their causes, and how they affect someone's life. Find out here what distinguishes the different forms of the disease, the various symptoms, treatment methods, and how blood tests are interpreted. Read now
Diabetes mellitus results mainly from a deficiency or diminished effectiveness of insulin that is normally produced by the beta cells of the pancreas. It is characterised by high blood sugar, altered sugar and glucose metabolism and this affects blood vessels and causes several organ damage. Causes of diabetes can be classified according to the types of diabetes.
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Doctors and people with diabetes have observed that infections seem more common if you have diabetes. Research in this area, however, has not proved whether this is entirely true, nor why. It may be that high levels of blood sugar impair your body's natural healing process and your ability to fight infections. For women, bladder and vaginal infections are especially common.
Insulin is the hormone responsible for reducing blood sugar. In order for insulin to work, our tissues have to be sensitive to its action; otherwise, tissues become resistant and insulin struggles to clear out sugar from the blood. As insulin resistance sets in, the first organ to stop responding to insulin is the liver, followed by the muscles and eventually fat. How does insulin resistance begin? The root of the problem is our diet.
While discovering you have diabetes can be a terrifying prospect, the sooner you’re treated, the more manageable your condition will be. In fact, a review of research published in the American Diabetes Association journal Diabetes Care reveals that early treatment with insulin can help patients with type 2 diabetes manage their blood sugar better and gain less weight than those who start treatment later.
People with Type 1 diabetes are usually totally dependent on insulin injections for survival. Such people require daily administration of insulin. The majority of people suffering from diabetes have the Type 2 form. Although they do not depend on insulin for survival, about one third of sufferers needs insulin for reducing their blood glucose levels.
In 2013, of the estimated 382 million people with diabetes globally, more than 80 per cent lived in LMIC. It was estimated that India had 65.1 million adults with diabetes in 2013, and had the 2nd position among the top 10 countries with the largest number of diabetes. This number is predicted to increase to 109 million by 2035 unless steps are taken to prevent new cases of diabetes1. Primary prevention of diabetes is feasible and strategies such as lifestyle modification are shown to be effective in populations of varied ethnicity2,3. However, for implementation of the strategies at the population level, national programmes which are culturally and socially acceptable and practical have to be formulated which are currently lacking in most of the developed and developing countries. Early diagnosis and institution of appropriate therapeutic measures yield the desired glycaemic outcomes and prevent the vascular complications4.
Diagnosis. The most common diagnostic tests for diabetes are chemical analyses of the blood such as the fasting plasma glucose. Capillary blood glucose monitoring can be used for screening large segments of the population. Portable equipment is available and only one drop of blood from the fingertip or earlobe is necessary. Capillary blood glucose levels have largely replaced analysis of the urine for glucose. Testing for urinary glucose can be problematic as the patient may have a high renal threshold, which would lead to a negative reading for urinary glucose when in fact the blood glucose level was high.
Older people may have a difficult time adding exercise to their daily life, particularly if they have not been active or if they have a disorder that limits their movement, such as arthritis. However, they may be able to add exercise to their usual routine. For example, they can walk instead of drive or climb the stairs instead of take the elevator. Also, many community organizations offer exercise programs designed for older people.
Low glycemic index foods also may be helpful. The glycemic index is a measure of how quickly a food causes a rise in your blood sugar. Foods with a high glycemic index raise your blood sugar quickly. Low glycemic index foods may help you achieve a more stable blood sugar. Foods with a low glycemic index typically are foods that are higher in fiber.
All you need to know about insulin sensitivity factor Insulin sensitivity factor is a measurement that describes how blood sugar levels are affected by taking 1 unit of insulin. It can help a person with type 1 diabetes regulate their blood sugar levels. Learn more about what insulin sensitivity factor is, who should test and when, and what the results mean. Read now
There are some interesting developments in blood glucose monitoring including continuous glucose sensors. The new continuous glucose sensor systems involve an implantable cannula placed just under the skin in the abdomen or in the arm. This cannula allows for frequent sampling of blood glucose levels. Attached to this is a transmitter that sends the data to a pager-like device. This device has a visual screen that allows the wearer to see, not only the current glucose reading, but also the graphic trends. In some devices, the rate of change of blood sugar is also shown. There are alarms for low and high sugar levels. Certain models will alarm if the rate of change indicates the wearer is at risk for dropping or rising blood glucose too rapidly. One version is specifically designed to interface with their insulin pumps. In most cases the patient still must manually approve any insulin dose (the pump cannot blindly respond to the glucose information it receives, it can only give a calculated suggestion as to whether the wearer should give insulin, and if so, how much). However, in 2013 the US FDA approved the first artificial pancreas type device, meaning an implanted sensor and pump combination that stops insulin delivery when glucose levels reach a certain low point. All of these devices need to be correlated to fingersticks measurements for a few hours before they can function independently. The devices can then provide readings for 3 to 5 days.

Pay attention if you find yourself feeling drowsy or lethargic; pain or numbness in your extremities; vision changes; fruity or sweet-smelling breath which is one of the symptoms of high ketones; and experiencing nausea or vomiting—as these are additional signs that something is not right. If there’s any question, see your doctor immediately to ensure that your blood sugar levels are safe and rule out diabetes.
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