Previously, CGMs required frequent calibration with fingerstick glucose testing. Also their results were not accurate enough so that people always had to do a fingerstick to verify a reading on their CGM before calculating a dose of insulin (for example before meals or to correct a high blood sugar). However, recent technological advances have improved CGMs. One professional CGM can be worn for up to 14 days without calibration. Another personal CGM can be used to guide insulin dosing without confirmation by fingerstick glucose. Finally, there are now systems in which the CGM device communicates with insulin pumps to either stop delivery of insulin when blood glucose is dropping (threshold suspend), or to give daily insulin (hybrid closed loop system).
Diet management is very important in people with both types of diabetes mellitus. Doctors recommend a healthy, balanced diet and efforts to maintain a healthy weight. People with diabetes can benefit from meeting with a dietitian or a diabetes educator to develop an optimal eating plan. Such a plan includes avoiding simple sugars and processed foods, increasing dietary fiber, limiting portions of carbohydrate-rich, and fatty foods (especially saturated fats). People who are taking insulin should avoid long periods between meals to prevent hypoglycemia. Although protein and fat in the diet contribute to the number of calories a person eats, only the number of carbohydrates has a direct effect on blood glucose levels. The American Diabetes Association has many helpful tips on diet, including recipes. Even when people follow a proper diet, cholesterol-lowering drugs are needed to decrease the risk of heart disease (see recommendations).
Over time, a prolonged exposure to high blood sugar can damage the nerves throughout the body — a condition called diabetic neuropathy. Some people may not have any symptoms of the damage, while others may notice numbness, tingling, or pain in the extremities. “At the beginning, [diabetic neuropathy] usually starts in the feet and then it progresses upward,” says Dr. Ovalle. Although most common in people who have had type 2 diabetes for 25 years or more, it can occur in people who have prediabetes as well. In some studies, almost 50 percent of unexplained peripheral neuropathy [in the extremities], whether painful or otherwise, turns out to be caused by prediabetes or diabetes, says Dr. Einhorn.
Oral glucose tolerance test (OGTT): With this test you will be required to fast for at least 8 hours and then are given a drink with 75 g of carbohydrate. Your blood glucose is checked at fasting and then 2 hours after drinking the solution. If your blood glucose is 11.1 mmol/L or higher, your doctor may diagnose diabetes. If your blood glucose 2 hours after drinking the solution is between 7.8 to 11.1 mmol/L, your doctor may diagnose prediabetes. This is the preferred method to test for gestational diabetes.

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.

To treat diabetic retinopathy, a laser is used to destroy and prevent the recurrence of the development of these small aneurysms and brittle blood vessels. Approximately 50% of patients with diabetes will develop some degree of diabetic retinopathy after 10 years of diabetes, and 80% retinopathy after 15 years of the disease. Poor control of blood sugar and blood pressure further aggravates eye disease in diabetes.

Taking the drugs used to treat diabetes, particularly insulin, may be difficult for some older people. For those with vision problems or other problems that make accurately filling a syringe difficult, a caregiver can prepare the syringes ahead of time and store them in the refrigerator. People whose insulin dose is stable may purchase pre-filled syringes. Prefilled insulin pen devices may be easier for people with physical limitations. Some of these devices have large numbers and easy-to-turn dials.
Diabetes has been recorded throughout history, since Egyptian times. It was given the name diabetes by the ancient Greek physician Aratus of Cappadocia. The full term, however, was not coined until 1675 in Britain by Thomas Willis, who rediscovered that the blood and urine of people with diabetes were sweet. This phenomenon had previously been discovered by ancient Indians.
Diabetes has often been referred to as a "silent disease" for two reasons: 1) Many people with Type 2 diabetes walk around with symptoms for many years, but are not diagnosed until they develop a complication of the disease, such as blindness, kidney disease, or heart disease; 2) There are no specific physical manifestations in individuals with diabetes.  Therefore, unless a person chooses to disclose their disease, it is possible that friends and even family members may be unaware of a person's diagnosis.
Type 1 diabetes is always treated with insulin, a life-saving treatment. Patients will need to take insulin several times a day for the rest of their lives. They will usually learn how to self-administer this. Insulin is usually given through injections under the skin, normally two to four times a day. An increasing number of patients with type 1 diabetes are being treated with ‘insulin pumps’, which provide a continuous supply of insulin. 

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%.
Can type 2 diabetes be cured? In the early stages of type 2 diabetes, it is possible to manage the diabetes to a level where symptoms go away and A1c reaches a normal level – this effectively “reverses” the progression of type 2 diabetes. According to research from Newcastle University, major weight loss can return insulin secretion to normal in people who had type 2 diabetes for four years or less. Indeed, it is commonly believed that significant weight loss and building muscle mass is the best way to reverse type 2 diabetes progression. However, it is important to note that reversing diabetes progression is not the same as curing type 2 diabetes – people still need to monitor their weight, diet, and exercise to ensure that type 2 diabetes does not progress. For many people who have had type 2 diabetes for a longer time, the damage to the beta cells progresses to the point at which it will never again be possible to make enough insulin to correctly control blood glucose, even with dramatic weight loss. But even in these people, weight loss is likely the best way to reduce the threat of complications.

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.
The term brittle diabetes has been used to refer to people who have dramatic recurrent swings in blood glucose levels, often for no apparent reason. However, this term is no longer used. People with type 1 diabetes may have more frequent swings in blood glucose levels because insulin production is completely absent. Infection, delayed movement of food through the stomach, and other hormonal disorders may also contribute to blood glucose swings. In all people who have difficulty controlling blood glucose, doctors look for other disorders that might be causing the problem and also give people additional education on how to monitor diabetes and take their drugs.
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]

Alternatively, if you hit it really hard for 20 minutes or so, you may never enter the fat burning phase of exercise. Consequently, your body becomes more efficient at storing sugar (in the form of glycogen) in your liver and muscles, where it is needed, as glycogen is the muscles’ primary fuel source. If your body is efficient at storing and using of glycogen, it means that it is not storing fat.

Elevated homocysteine levels in the blood called hyperhomocysteinemia, is a sign that the body isn't producing enough of the amino acid homocysteine. is a rare and serious condition that may be inherited (genetic). People with homocystinuria die at an early age. Symptoms of hyperhomocysteinemia include developmental delays, osteoporosis, blood clots, heart attack, heart disease, stroke, and visual abnormalities.

Hyperglycemia or high blood sugar is a serious health problem for diabetics. There are two types of hyperglycemia, 1) fasting, and 2)postprandial or after meal hyperglycemia. Hyperglycemia can also lead to ketoacidosis or hyperglycemic hyperosmolar nonketotic syndrome (HHNS). There are a variety of causes of hyperglycemia in people with diabetes. Symptoms of high blood sugar may include increased thirst, headaches, blurred vision, and frequent urination.Treatment can be achieved through lifestyle changes or medications changes. Carefully monitoring blood glucose levels is key to prevention.

Type 2 diabetes is mainly caused by insulin resistance. This means no matter how much or how little insulin is made, the body can't use it as well as it should. As a result, glucose can't be moved from the blood into cells. Over time, the excess sugar in the blood gradually poisons the pancreas causing it to make less insulin and making it even more difficult to keep blood glucose under control.

Type 2 diabetes was also previously referred to as non-insulin dependent diabetes mellitus (NIDDM), or adult-onset diabetes mellitus (AODM). In type 2 diabetes, patients can still produce insulin, but do so relatively inadequately for their body's needs, particularly in the face of insulin resistance as discussed above. In many cases this actually means the pancreas produces larger than normal quantities of insulin. A major feature of type 2 diabetes is a lack of sensitivity to insulin by the cells of the body (particularly fat and muscle cells).
The patient, physician, nurse, and dietician must carefully evaluate the patient's life style, nutritional needs, and ability to comply with the proposed dietary prescription. There are a variety of meal planning systems that can be used by the patient with diabetes; each has benefits and drawbacks that need to be evaluated in order to maximize compliance. Two of the most frequently used ones are the exchange system (see accompanying table) and the carbohydrate counting system.
Periodontal Disease. Periodontal disease is a commonly observed dental problem for patients with diabetes. It is similar to the periodontal disease encountered among nondiabetic patients. However, as a consequence of the impaired immunity and healing associated with diabetes, it may be more severe and progress more rapidly (see Right). The potential for these changes points to the need for periodic professional evaluation and treatment.
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.
How does type 2 diabetes progress over time? Type 2 diabetes is a progressive disease, meaning that the body’s ability to regulate blood sugar gets worse over time, despite careful management. Over time, the body’s cells become increasingly less responsive to insulin (increased insulin resistance) and beta cells in the pancreas produce less and less insulin (called beta-cell burnout). In fact, when people are diagnosed with type 2 diabetes, they usually have already lost up to 50% or more of their beta cell function. As type 2 diabetes progresses, people typically need to add one or more different types of medications. The good news is that there are many more choices available for treatments, and a number of these medications don’t cause as much hypoglycemia, hunger and/or weight gain (e.g., metformin, pioglitazone, DPP-4 inhibitors, GLP-1 agonists, SGLT-2 inhibitors, and better insulin). Diligent management early on can help preserve remaining beta cell function and sometimes slow progression of the disease, although the need to use more and different types of medications does not mean that you have failed.

About 84 million adults in the US (more than 1 out of 3) have prediabetes, and about 90% do not know they have it until a routine blood test is ordered, or symptoms of type 2 diabetes develop. For example, excessive thirst, frequent urination, and unexplained weight loss. If you have prediabetes also it puts you at risk for heart attack, stroke, and type 2 diabetes.
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 WHO estimates that diabetes mellitus resulted in 1.5 million deaths in 2012, making it the 8th leading cause of death.[9][101] However another 2.2 million deaths worldwide were attributable to high blood glucose and the increased risks of cardiovascular disease and other associated complications (e.g. kidney failure), which often lead to premature death and are often listed as the underlying cause on death certificates rather than diabetes.[101][104] For example, in 2014, the International Diabetes Federation (IDF) estimated that diabetes resulted in 4.9 million deaths worldwide,[19] using modeling to estimate the total number of deaths that could be directly or indirectly attributed to diabetes.[20]
Since cardiovascular disease is a serious complication associated with diabetes, some have recommended blood pressure levels below 130/80 mmHg.[89] However, evidence supports less than or equal to somewhere between 140/90 mmHg to 160/100 mmHg; the only additional benefit found for blood pressure targets beneath this range was an isolated decrease in stroke risk, and this was accompanied by an increased risk of other serious adverse events.[90][91] A 2016 review found potential harm to treating lower than 140 mmHg.[92] Among medications that lower blood pressure, angiotensin converting enzyme inhibitors (ACEIs) improve outcomes in those with DM while the similar medications angiotensin receptor blockers (ARBs) do not.[93] Aspirin is also recommended for people with cardiovascular problems, however routine use of aspirin has not been found to improve outcomes in uncomplicated diabetes.[94]
Diet. In general, the diabetic diet is geared toward providing adequate nutrition with sufficient calories to maintain normal body weight; the intake of food is adjusted so that blood sugar and serum cholesterol levels are kept within acceptable limits. Overweight diabetic patients should limit caloric intake until target weight is achieved. In persons with type 2 diabetes this usually results in marked improvement and may eliminate the need for drugs such as oral hypoglycemic agents.
Type 1 diabetes mellitus is predominantly a disease of the young, usually developing before 20 years of age. Overall, type I DM makes up approximately 15% of all cases of diabetes. It develops in approximately 1 in 600 children and is one of the most common chronic diseases in children. The incidence is relatively low for children under the age of 5, increases between 5 and 15, and then tapers off.
^ Jump up to: a b Cheng, J; Zhang, W; Zhang, X; Han, F; Li, X; He, X; Li, Q; Chen, J (May 2014). "Effect of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers on all-cause mortality, cardiovascular deaths, and cardiovascular events in patients with diabetes mellitus: a meta-analysis". JAMA Internal Medicine. 174 (5): 773–85. doi:10.1001/jamainternmed.2014.348. PMID 24687000.
Diabetes insipidus is considered very rare in less 20,000 cases diagnosed per year. Diabetes mellitus is more common, with type 2 diabetes being more common than type 1. There are more than 3 million cases of type 2 diabetes. Unlike diabetes mellitus, diabetes insipidus is not treated by controlling insulin levels. Depending on your symptoms, your doctor may prescribe a low-salt diet, hormone therapy, or have you increase your water intake. 
Autonomic changes involving cardiovascular control (eg, heart rate, postural responses) have been described in as many as 40% of children with diabetes. Cardiovascular control changes become more likely with increasing duration and worsening control. [18] In a study by 253 patients with type 1 diabetes (mean age at baseline 14.4 y), Cho et al reported that the prevalence of cardiac autonomic dysfunction increases in association with higher body mass index and central adiposity. [19]

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.