Insulin is essential to process carbohydrates, fat, and protein. Insulin reduces blood glucose levels by allowing glucose to enter muscle cells and by stimulating the conversion of glucose to glycogen (glycogenesis) as a carbohydrate store. Insulin also inhibits the release of stored glucose from liver glycogen (glycogenolysis) and slows the breakdown of fat to triglycerides, free fatty acids, and ketones. It also stimulates fat storage. Additionally, insulin inhibits the breakdown of protein and fat for glucose production (gluconeogenesis) in the liver and kidneys.
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. 
A metabolic disease in which carbohydrate use is reduced and that of lipid and protein enhanced; it is caused by an absolute or relative deficiency of insulin and is characterized, in more severe cases, by chronic hyperglycemia, glycosuria, water and electrolyte loss, ketoacidosis, and coma; long-term complications include neuropathy, retinopathy, nephropathy, generalized degenerative changes in large and small blood vessels, and increased susceptibility to infection.
Maturity onset diabetes of the young (MODY) is a rare autosomal dominant inherited form of diabetes, due to one of several single-gene mutations causing defects in insulin production.[52] It is significantly less common than the three main types. The name of this disease refers to early hypotheses as to its nature. Being due to a defective gene, this disease varies in age at presentation and in severity according to the specific gene defect; thus there are at least 13 subtypes of MODY. People with MODY often can control it without using insulin.
You can develop type 2 diabetes at any age, even during childhood. However, type 2 diabetes occurs most often in middle-aged and older people. You are more likely to develop type 2 diabetes if you are age 45 or older, have a family history of diabetes, or are overweight or obese. Diabetes is more common in people who are African American, Hispanic/Latino, American Indian, Asian American, or Pacific Islander.
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.
Progression toward type 2 diabetes may even be self-perpetuating. Once a person begins to become insulin resistant, for whatever reason, things may snowball from there. The increased levels of circulating insulin required to compensate for resistance encourage the body to pack on pounds. That extra weight will in turn make the body more insulin resistant. Furthermore, the heavier a person is, the more difficult it can be to exercise, continuing the slide toward diabetes.

Several common medications can impair the body's use of insulin, causing a condition known as secondary diabetes. These medications include treatments for high blood pressure (furosemide, clonidine, and thiazide diuretics), drugs with hormonal activity (oral contraceptives, thyroid hormone, progestins, and glucocorticorids), and the anti-inflammation drug indomethacin. Several drugs that are used to treat mood disorders (such as anxiety and depression) also can impair glucose absorption. These drugs include haloperidol, lithium carbonate, phenothiazines, tricyclic antidepressants, and adrenergic agonists. Other medications that can cause diabetes symptoms include isoniazid, nicotinic acid, cimetidine, and heparin. A 2004 study found that low levels of the essential mineral chromium in the body may be linked to increased risk for diseases associated with insulin resistance.
2.Retinopathy - Diabetes may cause blood vessels in the retina (the light sensitive lining of the eye) to become leaky, blocked, or grow abnormally [Figure 1]. Retinopathy is rare before the age of 10 and the risk increases with the length of time a person has diabetes. Treatments such as laser, injections in the eye, or other procedures may be helpful to prevent visual loss or restore sight. The longer a patient has diabetes, the greater chance of developing an eye problem.  All patients with diabetes are at risk for developing retinopathy, but the risk is higher for patients with worse blood sugar control.  Early retinopathy may have no symptoms, but early treatment is essential to prevent any loss of vision.
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.
Women seem to be at a greater risk as do certain ethnic groups,[10][107] such as South Asians, Pacific Islanders, Latinos, and Native Americans.[23] This may be due to enhanced sensitivity to a Western lifestyle in certain ethnic groups.[108] Traditionally considered a disease of adults, type 2 diabetes is increasingly diagnosed in children in parallel with rising obesity rates.[10] Type 2 diabetes is now diagnosed as frequently as type 1 diabetes in teenagers in the United States.[13]
Insulin — the hormone that allows your body to regulate sugar in the blood — is made in your pancreas. Essentially, insulin resistance is a state in which the body’s cells do not use insulin efficiently. As a result, it takes more insulin than normal to transport blood sugar (glucose) into cells, to be used immediately for fuel or stored for later use. A drop in efficiency in getting glucose to cells creates a problem for cell function; glucose is normally the body’s quickest and most readily available source of energy.
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.
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"?)
Culturally appropriate education may help people with type 2 diabetes control their blood sugar levels, for up to 24 months.[89] If changes in lifestyle in those with mild diabetes has not resulted in improved blood sugars within six weeks, medications should then be considered.[23] There is not enough evidence to determine if lifestyle interventions affect mortality in those who already have DM2.[62]
Diabetes mellitus is a public health problem around the world. In 1980, 108 million adults worldwide had diabetes (4.7% of the global population). By 2014 this had risen to 422 million adults (8.5% of the global population). By 2040, the number is expected to be 642 million adults. In the UK, there is estimated to be between 3 and 4 million people with diabetes. Type 2 diabetes accounts for more than 90% of all patients with diabetes. 
Diabetes means your blood glucose, or blood sugar, levels are too high. With type 2 diabetes, the more common type, your body does not make or use insulin well. Insulin is a hormone that helps glucose get into your cells to give them energy. Without insulin, too much glucose stays in your blood. Over time, high blood glucose can lead to serious problems with your heart, eyes, kidneys, nerves, and gums and teeth.

While it's conceivable that scientists will isolate a single factor as causing type 1 and type 2, the much more likely outcome is that there is more than one cause. Each person seems to take a unique path in developing diabetes. Someday, doctors may be able to assess an individual's genetic risk for diabetes, allowing him or her to dodge the particular environmental factors that would trigger the disease. And perhaps if the baffling question of why a person gets diabetes can be put to rest, the answer will also offer a cure for the disease.


People with T2D produce insulin, but their bodies don’t use it correctly; this is referred to as being insulin resistant. People with type 2 diabetes may also be unable to produce enough insulin to handle the glucose in their body. In these instances, insulin is needed to allow the glucose to travel from the bloodstream into our cells, where it’s used to create energy.

In ‘type 2 diabetes’ (previously called non-insulin-dependent diabetes mellitus), which accounts for 90% of all diabetes, the beta cells do not stop making insulin completely, but the insulin produced does not work properly so it struggles to store the sugar found in the blood. As a consequence, the pancreas has to produce more insulin to compensate for this reduction in insulin function. This is called insulin resistance and is commonly linked to obesity. This type of diabetes is seen more commonly over the age of 40 years but can occur at any age.  
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.

Diabetes mellitus (DM), commonly referred to as diabetes, is a group of metabolic disorders in which there are high blood sugar levels over a prolonged period.[10] Symptoms of high blood sugar include frequent urination, increased thirst, and increased hunger.[2] If left untreated, diabetes can cause many complications.[2] Acute complications can include diabetic ketoacidosis, hyperosmolar hyperglycemic state, or death.[3] Serious long-term complications include cardiovascular disease, stroke, chronic kidney disease, foot ulcers, and damage to the eyes.[2]
Prediabetes is a condition in which blood glucose levels are too high to be considered normal but not high enough to be labeled diabetes. People have prediabetes if their fasting blood glucose level is between 100 mg/dL and 125 mg/dL or if their blood glucose level 2 hours after a glucose tolerance test is between 140 mg/dL and 199 mg/dL. Prediabetes carries a higher risk of future diabetes as well as heart disease. Decreasing body weight by 5 to 10% through diet and exercise can significantly reduce the risk of developing future diabetes.
There are other factors that also fall into the category of environmental (as opposed to genetic) causes of diabetes. Certain injuries to the pancreas, from physical trauma or from drugs, can harm beta cells, leading to diabetes. Studies have also found that people who live in polluted areas are prone to type 2, perhaps because of inflammation. And an alternate theory of insulin resistance places the blame on damage caused by inflammation. Age also factors into type 2; beta cells can wear out over time and become less capable of producing enough insulin to overcome insulin resistance, which is why older people are at greater risk of type 2.
Blood travels throughout your body, and when too much glucose (sugar) is present, it disrupts the normal environment that the organ systems of your body function within. In turn, your body starts to exhibit signs that things are not working properly inside—those are the symptoms of diabetes people sometimes experience. If this problem—caused by a variety of factors—is left untreated, it can lead to a number of damaging complications such as heart attacks, strokes, blindness, kidney failure, and blood vessel disease that may require an amputation, nerve damage, and impotence in men.
Patients with type 1 diabetes require life-long treatment with exogenous (artificial) insulin to regulate their blood sugar levels. This insulin may be given through the use of a hypodermic needle (seen right), or other methods such as the use of an insulin pump. Over time, many patients suffer chronic complications: vascular, neurological and organ-specific (such as kidney and eye disease). The frequency and severity of these complications is related to duration that the patient has suffered the disease for, and by how well their blood sugar levels have been controlled. If blood sugar levels, blood pressure and lipids are tightly controlled, many complications of diabetes may be prevented. Some patients may develop the major emergency complication of diabetes, known as ketoacidosis (extremely high blood glucose levels accompanied with extremely low insulin levels), which has a mortality rate of 5-10%.

The symptoms may relate to fluid loss and polyuria, but the course may also be insidious. Diabetic animals are more prone to infections. The long-term complications recognized in humans are much rarer in animals. The principles of treatment (weight loss, oral antidiabetics, subcutaneous insulin) and management of emergencies (e.g. ketoacidosis) are similar to those in humans.[123]

Most cases (95%) of type 1 diabetes mellitus are the result of environmental factors interacting with a genetically susceptible person. This interaction leads to the development of autoimmune disease directed at the insulin-producing cells of the pancreatic islets of Langerhans. These cells are progressively destroyed, with insulin deficiency usually developing after the destruction of 90% of islet cells.
American Diabetes Association Joslin Diabetes Center Mayo Clinic International Diabetes Federation Canadian Diabetes Association National Institute of Diabetes and Digestive and Kidney Diseases Diabetes Daily American Heart Association Diabetes Forecast Diabetic Living American Association of Clinical Endocrinologists European Association for the Study of Diabetes
Diabetes also can cause heart disease and stroke, as well as other long-term complications, including eye problems, kidney disease, nerve damage, and gum disease. While these problems don't usually show up in kids or teens who've had type 2 diabetes for only a few years, they can affect them in adulthood, particularly if their diabetes isn't well controlled.

A metabolic disease in which carbohydrate use is reduced and that of lipid and protein enhanced; it is caused by an absolute or relative deficiency of insulin and is characterized, in more severe cases, by chronic hyperglycemia, glycosuria, water and electrolyte loss, ketoacidosis, and coma; long-term complications include neuropathy, retinopathy, nephropathy, generalized degenerative changes in large and small blood vessels, and increased susceptibility to infection.


Our bodies break down the foods we eat into glucose and other nutrients we need, which are then absorbed into the bloodstream from the gastrointestinal tract. The glucose level in the blood rises after a meal and triggers the pancreas to make the hormone insulin and release it into the bloodstream. But in people with diabetes, the body either can't make or can't respond to insulin properly.


When you have type 2 diabetes, your cells don't get enough glucose, which may cause you to lose weight. Also, if you are urinating more frequently because of uncontrolled diabetes, you may lose more calories and water, resulting in weight loss, says Daniel Einhorn, MD, medical director of the Scripps Whittier Diabetes Institute and clinical professor of medicine at the University of California in San Diego.
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