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.

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 is 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 is a hormone made by your pancreas that acts like a key to let blood sugar into the cells in your body for use as energy. If you have type 2 diabetes, cells don’t respond normally to insulin; this is called insulin resistance. Your pancreas makes more insulin to try to get cells to respond. Eventually your pancreas can’t keep up, and your blood sugar rises, setting the stage for prediabetes and type 2 diabetes. High blood sugar is damaging to the body and can cause other serious health problems, such as heart disease, vision loss, and kidney disease.

Type 2 DM begins with insulin resistance, a condition in which cells fail to respond to insulin properly.[2] As the disease progresses, a lack of insulin may also develop.[12] This form was previously referred to as "non insulin-dependent diabetes mellitus" (NIDDM) or "adult-onset diabetes".[2] The most common cause is excessive body weight and insufficient exercise.[2]
Having diabetes requires life-long treatment and follow-up by health professionals. Diabetes can be linked to damage of the eyes, kidneys and feet. It is also associated with increased risk of strokes, heart attacks and poor blood circulation to the legs. Medical care aims to minimise these risks by controlling diabetes, blood pressure and cholesterol and screening for possible complications caused by the diabetes. 
central diabetes insipidus a metabolic disorder due to injury of the neurohypophyseal system, which results in a deficient quantity of antidiuretic hormone (ADH or vasopressin) being released or produced, resulting in failure of tubular reabsorption of water in the kidney. As a consequence, there is the passage of a large amount of urine having a low specific gravity, and great thirst; it is often attended by voracious appetite, loss of strength, and emaciation. Diabetes insipidus may be acquired through infection, neoplasm, trauma, or radiation injuries to the posterior lobe of the pituitary gland or it may be inherited or idiopathic.
Whether you’re dealing with frequent UTIs or skin infections, undiagnosed diabetes may be to blame. The high blood sugar associated with diabetes can weaken a person’s immune system, making them more susceptible to infection. In more advanced cases of the disease, nerve damage and tissue death can open people up to further infections, often in the skin, and could be a precursor to amputation.
5. Signs and symptoms ofhyperglycemiaandhypoglycemia, and measures to take when they occur. (See accompanying table.) It is important for patients to become familiar with specific signs that are unique to themselves. Each person responds differently and may exhibit symptoms different from those experienced by others. It should be noted that the signs and symptoms may vary even within one individual. Thus it is vital that the person understand all reactions that could occur. When there is doubt, a simple blood glucose reading will determine the actions that should be taken.
The body will attempt to dilute the high level of glucose in the blood, a condition called hyperglycemia, by drawing water out of the cells and into the bloodstream in an effort to dilute the sugar and excrete it in the urine. It is not unusual for people with undiagnosed diabetes to be constantly thirsty, drink large quantities of water, and urinate frequently as their bodies try to get rid of the extra glucose. This creates high levels of glucose in the urine.

Type 1 diabetes mellitus can occur at any age, but incidence rates generally increase with age until midpuberty and then decline. [32] Onset in the first year of life, although unusual, can occur, so type 1 diabetes mellitus must be considered in any infant or toddler, because these children have the greatest risk for mortality if diagnosis is delayed. (Because diabetes is easily missed in an infant or preschool-aged child, if in doubt, check the urine for glucose.) Symptoms in infants and toddlers may include the following:
Another form of diabetes called gestational diabetes can develop during pregnancy and generally resolves after the baby is delivered. This diabetic condition develops during the second or third trimester of pregnancy in about 2% of pregnancies. In 2004, incidence of gestational diabetes were reported to have increased 35% in 10 years. Children of women with gestational diabetes are more likely to be born prematurely, have hypoglycemia, or have severe jaundice at birth. The condition usually is treated by diet, however, insulin injections may be required. These women who have diabetes during pregnancy are at higher risk for developing Type II diabetes within 5-10 years.
The most common complication of treating high blood glucose levels is low blood glucose levels (hypoglycemia). The risk is greatest for older people who are frail, who are sick enough to require frequent hospital admissions, or who are taking several drugs. Of all available drugs to treat diabetes, long-acting sulfonylurea drugs are most likely to cause low blood glucose levels in older people. When they take these drugs, they are also more likely to have serious symptoms, such as fainting and falling, and to have difficulty thinking or using parts of the body due to low blood glucose levels.

It isn't always easy to start an exercise regimen, but once you get into a groove, you may be surprised at how much you enjoy it. Find a way to fit activity into your daily routine. Even a few minutes a day goes a long way. The American Diabetes Association recommends that adults with diabetes should perform at least 150 minutes of moderate-intensity aerobic physical activity per week (spread over at least three days with no more than two consecutive days without exercise). You don't have to start with this right away, though. Start with five to 10 minutes per day and go from there. To stay motivated, find a buddy, get a fitness tracker, or use another measurement tool that can help you see your progress.

Excess glucose in the blood can damage small blood vessels in the nerves causing a tingling sensation or pain in the fingers, toes and limbs. Nerves that lie outside of the central nervous system may also be damaged, which is referred to as peripheral neuropathy. If nerves of the gastrointestinal tract are affected, this may cause vomiting, constipation and diarrhea.
If genetics has taught us anything about diabetes, it's that, for most people, genes aren't the whole story. True, a few rare kinds of diabetes—including those collectively called MODY for maturity-onset diabetes of the young—have been traced to defects in a single gene. But for other types of diabetes, hereditary factors are still not well understood.
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.
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.
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
Reduce Your Carbohydrate Intake: One of the most important components involved in a diabetes diet is knowing how to eat a modified carbohydrate diet. Carbohydrates are the nutrient that impacts blood sugars the most. Carbohydrates are found in starches, fruit, some vegetables like potatoes, sweets, and grains. Eating the right kinds of carbohydrate in the right quantities can help you manage your weight and your blood sugars. Knowing how to identify and count carbohydrates is very important in managing diabetes. Eating a consistent carbohydrate diet is ideal because it can help you body regulate blood sugars.
A 2018 study suggested that three types should be abandoned as too simplistic.[57] It classified diabetes into five subgroups, with what is typically described as type 1 and autoimmune late-onset diabetes categorized as one group, whereas type 2 encompasses four categories. This is hoped to improve diabetes treatment by tailoring it more specifically to the subgroups.[58]

High blood sugar levels (hyperglycemia) can lead to a condition called glucose toxicity. This leads to further damage to the pancreas, and the body is less able to produce insulin. Without insulin, glucose levels continue to rise to levels that can cause damage to organs such as the eyes, nerves, and kidneys. These problems are similar to the complications associated with type 1 diabetes.
Type 2 diabetes can be prevented with lifestyle changes. People who are overweight and lose as little as 7 percent of their body weight and who increase physical activity (for example, walking 30 minutes per day) can decrease their risk of diabetes mellitus by more than 50%. Metformin and acarbose, drugs that are used to treat diabetes, may reduce the risk of diabetes in people with impaired glucose regulation.
[1] Diabetes Prevention Program Research Group. Long-term effects of lifestyle intervention or metformin on diabetes development and microvascular complications over 15-year follow-up: the Diabetes Prevention Program Outcomes Study. The Lancet Diabetes & Endocrinology. 2015;3(11):866‒875. You can find more information about this study on the Diabetes Prevention Program Outcomes Study website.
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.

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]
FIGURE 19-1 ■. This figure shows the hyperbolic relationship of insulin resistance and beta cell function. On the y-axis is beta cell function as reflected in the first-phase insulin response during intravenous (IV) glucose infusion; on the x-axis is insulin sensitivity and its mirror image resistance. In a subject with normal glucose tolerance (NGT) and beta-cell reserve, an increase in insulin resistance results in increased insulin release and normal glucose tolerance. In an individual for whom the capacity to increase insulin release is compromised, increasing insulin resistance with partial or no beta-cell compensation results in progression from normal glucose tolerance, to impaired glucose tolerance (IGT), and finally to diabetes (T2D). Differences between these categories are small at high insulin sensitivity, which may be maintained by weight reduction, exercise, and certain drugs. At a critical degree of insulin resistance, due to obesity or other listed factors, only a further small increment in resistance requires a large increase in insulin output. Those that can increase insulin secretion to this extent retain normal glucose tolerance; those who cannot achieve this degree of insulin secretion (e.g., due to a mild defect in genes regulating insulin synthesis, insulin secretion, insulin action, or an ongoing immune destruction of beta cells) now unmask varying degrees of carbohydrate intolerance. The product of insulin sensitivity (the reciprocal of insulin resistance) and acute insulin response (a measurement beta-cell function) has been called the “disposition index.” This index remains constant in an individual with normal beta cell compensation in response to changes in insulin resistance. IGT, impaired glucose tolerance; NGT, normal glucose tolerance; T2D, type 2 diabetes.
Some cases of diabetes are caused by the body's tissue receptors not responding to insulin (even when insulin levels are normal, which is what separates it from type 2 diabetes); this form is very uncommon. Genetic mutations (autosomal or mitochondrial) can lead to defects in beta cell function. Abnormal insulin action may also have been genetically determined in some cases. Any disease that causes extensive damage to the pancreas may lead to diabetes (for example, chronic pancreatitis and cystic fibrosis). Diseases associated with excessive secretion of insulin-antagonistic hormones can cause diabetes (which is typically resolved once the hormone excess is removed). Many drugs impair insulin secretion and some toxins damage pancreatic beta cells. The ICD-10 (1992) diagnostic entity, malnutrition-related diabetes mellitus (MRDM or MMDM, ICD-10 code E12), was deprecated by the World Health Organization (WHO) when the current taxonomy was introduced in 1999.[53]
"We know that there is a very large genetic component," Rettinger says. "A person with a first-degree relative with Type 2 diabetes has a five to 10 time higher risk of developing diabetes than a person the same age and weight without a family history of Type 2 diabetes." Heredity actually plays a larger role in Type 2 diabetes than Type 1, Rettinger says.

Jump up ^ Farmer, AJ; Perera, R; Ward, A; Heneghan, C; Oke, J; Barnett, AH; Davidson, MB; Guerci, B; Coates, V; Schwedes, U; O'Malley, S (27 February 2012). "Meta-analysis of individual patient data in randomised trials of self monitoring of blood glucose in people with non-insulin treated type 2 diabetes". The BMJ. 344: e486. doi:10.1136/bmj.e486. PMID 22371867.
Weight fluctuations also fall under the umbrella of possible diabetes signs and symptoms. When you lose sugar through frequent urination, you also lose calories. At the same time, diabetes may keep the sugar from your food from reaching your cells — leading to constant hunger. The combined effect is potentially rapid weight loss, especially if you have type 1 diabetes.

Then, once you do have an injury, uncontrolled diabetes can make it harder for your body to heal. “High blood sugars provide a good environment for bacteria to grow,” she says. That's because diabetes is also often accompanied by high blood pressure and high cholesterol, and the resulting plaque buildup can narrow blood vessels, reducing blood supply and leading to slow healing.