Type 2 diabetes mellitus (non–insulin-dependent diabetes mellitus [NIDDM]) is a heterogeneous disorder. Most patients with type 2 diabetes mellitus have insulin resistance, and their beta cells lack the ability to overcome this resistance.  Although this form of diabetes was previously uncommon in children, in some countries, 20% or more of new patients with diabetes in childhood and adolescence have type 2 diabetes mellitus, a change associated with increased rates of obesity. Other patients may have inherited disorders of insulin release, leading to maturity onset diabetes of the young (MODY) or congenital diabetes. [7, 8, 9] This topic addresses only type 1 diabetes mellitus. (See Etiology and Epidemiology.)
Symptoms of type 1 diabetes can start quickly, in a matter of weeks. Symptoms of type 2 diabetes often develop slowly—over the course of several years—and can be so mild that you might not even notice them. Many people with type 2 diabetes have no symptoms. Some people do not find out they have the disease until they have diabetes-related health problems, such as blurred vision or heart trouble.
Blood sugar should be regularly monitored so that any problems can be detected and treated early. Treatment involves lifestyle changes such as eating a healthy and balanced diet and regular physical exercise. If lifestyle changes alone are not enough to regulate the blood glucose level, anti-diabetic medication in the form of tablets or injections may be prescribed. In some cases, people who have had type 2 diabetes for many years are eventually prescribed insulin injections.
The term "type 1 diabetes" has replaced several former terms, including childhood-onset diabetes, juvenile diabetes, and insulin-dependent diabetes mellitus (IDDM). Likewise, the term "type 2 diabetes" has replaced several former terms, including adult-onset diabetes, obesity-related diabetes, and noninsulin-dependent diabetes mellitus (NIDDM). Beyond these two types, there is no agreed-upon standard nomenclature.
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In the exchange system, foods are divided into six food groups (starch, meat, vegetable, fruit, milk, and fat) and the patient is taught to select items from each food group as ordered. Items in each group may be exchanged for each other in specified portions. The patient should avoid concentrated sweets and should increase fiber in the diet. Special dietetic foods are not necessary. Patient teaching should emphasize that a diabetic diet is a healthy diet that all members of the family can follow.
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.
Yet carbs are processed differently in the body based on their type: While simple carbs are digested and metabolized quickly, complex carbs take longer to go through this system, resulting in more stable blood sugar. “It comes down to their chemical forms: A simple carbohydrate has a simpler chemical makeup, so it doesn’t take as much for it to be digested, whereas the complex ones take a little longer,” Grieger explains.
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
There are a number of medications and other health problems that can predispose to diabetes. Some of the medications include: glucocorticoids, thiazides, beta blockers, atypical antipsychotics, and statins. Those who have previously had gestational diabetes are at a higher risk of developing type 2 diabetes. Other health problems that are associated include: acromegaly, Cushing's syndrome, hyperthyroidism, pheochromocytoma, and certain cancers such as glucagonomas. Testosterone deficiency is also associated with type 2 diabetes.
The problem with sugar, regardless of type, is the sheer amount of it that’s found in the Standard American Diet (SAD), which is the typical eating plan many people in the United States — as well as those in an increasing number of modernized countries — have developed a taste for. When consumed in excess, foods in this category can lead to heart disease, stroke, and other serious health issues. “Often, foods with added sugar also contain fat,” explains Grieger, noting that these components go hand in hand when it comes to the risk for insulin resistance, the hallmark of type 2 diabetes.
If sugars in general are not associated with increased diabetes risk, but sodas are, it suggests the possibility that something other than sugar explains this relationship.16 Sodas are often accompanied by cheeseburgers, chicken nuggets, and other unhealthful foods. That is, soda consumption can be a sign of a diet focusing on fast foods or an overall unhealthful diet and lifestyle. And sugary snack foods (e.g., cookies and snack pastries) are often high in fat; the sugar lures us in to the fat calories hiding inside. Some, but not all, observational trials have sought to control for these confounding variables.
Type 2 diabetes is believed to have a strong genetic link, meaning that it tends to run in families. Several genes are being studied that may be related to the cause of type 2 diabetes. If you have any of the following type 2 diabetes risk factors, it’s important to ask your doctor about a diabetes test. With a proper diabetes diet and healthy lifestyle habits, along with diabetes medication, if necessary, you can manage type 2 diabetes just like you manage other areas of your life. Be sure to continue seeking the latest information on type 2 diabetes as you become your own health advocate.
When you have Type 2 diabetes, you may start out with something called insulin resistance. This means your cells do not respond well to the insulin you are making. "Insulin levels may be quite high, especially in the early stages of the disease. Eventually, your pancreas may not be able to keep up, and insulin secretion goes down," Rettinger explains. Insulin resistance becomes more common as you put on more weight, especially weight around your belly.
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.
Insulin treatment can cause weight gain and low blood sugar. In addition, there may be discomfort at the injection site. There are several types of tablets used to treat diabetes and they have different side-effects. The most common are diarrhoea (metformin), nausea (GLP-1 agoniists), weight-gain (sulphonylureas and pioglitazone), low blood sugar (sulphonylureas) and genital thrush (SGLT2 inhibitors). However, not all patients will experience some or any of these side-effects and patients should discuss any concerns with their doctor.
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.
Childhood obesity rates are rising, and so are the rates of type 2 diabetes in youth. More than 75% of children with type 2 diabetes have a close relative who has it, too. But it’s not always because family members are related; it can also be because they share certain habits that can increase their risk. Parents can help prevent or delay type 2 diabetes by developing a plan for the whole family:
When you have diabetes, your body becomes less efficient at breaking food down into sugar, so you have more sugar sitting in your bloodstream, says Dobbins. “Your body gets rid of it by flushing it out in the urine.” So going to the bathroom a lot could be one of the diabetes symptoms you’re missing. Most patients aren’t necessarily aware of how often they use the bathroom, says Dr. Cypess. “When we ask about it, we often hear, ‘Oh yeah, I guess I’m going more often than I used to,’” he says. But one red flag is whether the need to urinate keeps you up at night. Once or twice might be normal, but if it’s affecting your ability to sleep, that could be a diabetes symptom to pay attention to. Make sure you know these diabetes myths that could sabotage your health.
Family or personal history. Your risk increases if you have prediabetes — a precursor to type 2 diabetes — or if a close family member, such as a parent or sibling, has type 2 diabetes. You're also at greater risk if you had gestational diabetes during a previous pregnancy, if you delivered a very large baby or if you had an unexplained stillbirth.