Cataracts and glaucoma are also more common among diabetics. It is also important to note that since the lens of the eye lets water through, if blood sugar concentrations vary a lot, the lens of the eye will shrink and swell with fluid accordingly. As a result, blurry vision is very common in poorly controlled diabetes. Patients are usually discouraged from getting a new eyeglass prescription until their blood sugar is controlled. This allows for a more accurate assessment of what kind of glasses prescription is required.


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]
Low blood sugar (hypoglycemia), is common in people with type 1 and type 2 DM. Most cases are mild and are not considered medical emergencies. Effects can range from feelings of unease, sweating, trembling, and increased appetite in mild cases to more serious effects such as confusion, changes in behavior such as aggressiveness, seizures, unconsciousness, and (rarely) permanent brain damage or death in severe cases.[24][25] Moderately low blood sugar may easily be mistaken for drunkenness;[26] rapid breathing and sweating, cold, pale skin are characteristic of low blood sugar but not definitive.[27] Mild to moderate cases are self-treated by eating or drinking something high in sugar. Severe cases can lead to unconsciousness and must be treated with intravenous glucose or injections with glucagon.[28]
By simultaneously considering insulin secretion and insulin action in any given individual, it becomes possible to account for the natural history of diabetes in that person (e.g., remission in a patient with T1 diabetes or ketoacidosis in a person with T2DM). Thus, diabetes mellitus may be the result of absolute insulin deficiency, or of absolute insulin resistance, or a combination of milder defects in both insulin secretion and insulin action.1 Collectively, the syndromes of diabetes mellitus are the most common endocrine/metabolic disorders of childhood and adolescence. The application of molecular biologic tools continues to provide remarkable insights into the etiology, pathophysiology, and genetics of the various forms of diabetes mellitus that result from deficient secretion of insulin or its action at the cellular level.
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.
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Doctors may recommend one or more types of medications to help control diabetes. While taking medications, it's important for people with diabetes to regularly test their blood glucose levels at home. There are many different blood glucose meters available on the market. Speak to a doctor or pharmacist about these meters to help you select the best meter for your needs.
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.)
Is it your fault for getting type 2 diabetes? No – type 2 diabetes is not a personal failing. It develops through a combination of factors that are still being uncovered and better understood. Lifestyle (food, exercise, stress, sleep) certainly plays a major role, but genetics play a significant role as well. Type 2 diabetes is often described in the media as a result of being overweight, but the relationship is not that simple. Many overweight individuals never get type 2, and some people with type 2 were never overweight, (although obesity is probably an underlying cause of insulin resistance). To make matters worse, when someone gains weight (for whatever reason), the body makes it extremely difficult to lose the new weight and keep it off. If it were just a matter of choice or a bit of willpower, we would probably all be skinny. At its core, type 2 involves two physiological issues: resistance to the insulin made by the person’s beta cells and too little insulin production relative to the amount one needs.

Type 2 diabetes is a condition of blood sugar dysregulation. In general blood sugar is too high, but it also can be too low. This can happen if you take medications then skip a meal. Blood sugar also can rise very quickly after a high glycemic index meal, and then fall a few hours later, plummeting into hypoglycemia (low blood sugar). The signs and symptoms of hypoglycemia can include
If eaten as part of a healthy meal plan, or combined with exercise, sweets and desserts can be eaten by people with diabetes. They are no more "off limits" to people with diabetes than they are to people without diabetes. The key to sweets is to have a very small portion and save them for special occasions so you focus your meal on more healthful foods.
Insulin works like a key that opens the doors to cells and lets the glucose in. Without insulin, glucose can't get into the cells (the doors are "locked" and there is no key) and so it stays in the bloodstream. As a result, the level of sugar in the blood remains higher than normal. High blood sugar levels are a problem because they can cause a number of health problems.
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.
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.
Although some people with this type of diabetes are thin, the majority of people (90%) are overweight. Losing weight, even 2 kg to 5 kg (5 lbs to 10 lbs) can help lower blood glucose levels. For many people, following a healthy diet and an exercise program may be all that is needed to help control glucose levels. For others, healthy eating and exercise alone aren't enough to lower blood glucose levels.

Exercise. A program of regular exercise gives anyone a sense of good health and well-being; for persons with diabetes it gives added benefits by helping to control blood glucose levels, promoting circulation to peripheral tissues, and strengthening the heart beat. In addition, there is evidence that exercise increases the number of insulin receptor sites on the surface of cells and thus facilitates the metabolism of glucose. Many specialists in diabetes consider exercise so important in the management of diabetes that they prescribe rather than suggest exercise.
Diabetes experts feel that these blood glucose monitoring devices give patients a significant amount of independence to manage their disease process; and they are a great tool for education as well. It is also important to remember that these devices can be used intermittently with fingerstick measurements. For example, a well-controlled patient with diabetes can rely on fingerstick glucose checks a few times a day and do well. If they become ill, if they decide to embark on a new exercise regimen, if they change their diet and so on, they can use the sensor to supplement their fingerstick regimen, providing more information on how they are responding to new lifestyle changes or stressors. This kind of system takes us one step closer to closing the loop, and to the development of an artificial pancreas that senses insulin requirements based on glucose levels and the body's needs and releases insulin accordingly - the ultimate goal.

Unlike people with type 1 diabetes, people with type 2 diabetes produce insulin; however, the insulin their pancreas secretes is either not enough or the body is unable to recognize the insulin and use it properly (insulin resistance). When there isn't enough insulin or the insulin is not used as it should be, glucose (sugar) can't get into the body's cells and builds up in the bloodstream instead. When glucose builds up in the blood instead of going into cells, it causes damage in multiple areas of the body. Also, since cells aren't getting the glucose they need, they can't function properly.


All children with type 1 diabetes mellitus require insulin therapy. Most require 2 or more injections of insulin daily, with doses adjusted on the basis of self-monitoring of blood glucose levels. Insulin replacement is accomplished by giving a basal insulin and a preprandial (premeal) insulin. The basal insulin is either long-acting (glargine or detemir) or intermediate-acting (NPH). The preprandial insulin is either rapid-acting (lispro, aspart, or glulisine) or short-acting (regular).
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Over recent decades, and particularly in the past five years, researchers have found dozens of genes with links to diabetes. The count stands at about 50 genes for type 1 and 38 for type 2. The numbers have risen quickly in recent years because of advances in the gene-sequencing technology used to conduct genome-wide association studies. This technique involves taking the genetic compositions of a group of people with a disease and comparing them en masse to the genomes of people who don't have the disease.
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]
Test Your Blood Sugar: Blood sugar testing is an important part of helping to manage your diabetes. Whether you choose to do selective blood sugar testing or test your blood sugar at the same times daily, blood sugar testing gives you another piece of information and can help you change your diet and adjust your fitness routine or medicines. Keeping your blood sugars at target will help to reduce diabetes complications.
Diabetes is a serious and costly disease which is becoming increasingly common, especially in developing countries and disadvantaged minorities. However, there are ways of preventing it and/or controlling its progress. Public and professional awareness of the risk factors for, and symptoms of diabetes are an important step towards its prevention and control.
The word diabetes (/ˌdaɪ.əˈbiːtiːz/ or /ˌdaɪ.əˈbiːtɪs/) comes from Latin diabētēs, which in turn comes from Ancient Greek διαβήτης (diabētēs), which literally means "a passer through; a siphon".[111] Ancient Greek physician Aretaeus of Cappadocia (fl. 1st century CE) used that word, with the intended meaning "excessive discharge of urine", as the name for the disease.[112][113] Ultimately, the word comes from Greek διαβαίνειν (diabainein), meaning "to pass through,"[111] which is composed of δια- (dia-), meaning "through" and βαίνειν (bainein), meaning "to go".[112] The word "diabetes" is first recorded in English, in the form diabete, in a medical text written around 1425.
Polyuria is defined as an increase in the frequency of urination. When you have abnormally high levels of sugar in your blood, your kidneys draw in water from your tissues to dilute that sugar, so that your body can get rid of it through the urine. The cells are also pumping water into the bloodstream to help flush out sugar, and the kidneys are unable to reabsorb this fluid during filtering, which results in excess urination.
Eating a balanced diet that is rich in fiber, non-starchy vegetables, lean protein, and healthy fat can help get you to your goal weight and reduce your waist size and body mass index (BMI). Reducing your intake of sweetened beverages (juices, sodas) is the easiest way to lose weight and reduce blood sugars. If you are someone who has high blood pressure and are salt sensitive, aim to reduce your intake of sodium; do not add salt to your food, read package labels for added sodium, and reduce your intake of fast food and take out. Don't go on a diet. Instead, adapt a healthier way of eating, one that you'll enjoy for a long time.
According to the Mayo Clinic, doctors may use other tests to diagnose diabetes. For example, they may conduct a fasting blood glucose test, which is a blood glucose test done after a night of fasting. While a fasting blood sugar level of less than 100 milligrams per deciliter (mg/dL) is normal, one that is between 100 to 125 mg/dL signals prediabetes, and a reading that reaches 126 mg/dL on two separate occasions means you have diabetes.
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