What is diabetes?

Diabetes is a chronic illness that compromises the body’s ability to produce and respond to the creation of insulin, the hormone that transforms glucose (sugar) into energy. When too little insulin is produced or the body does not respond to the insulin present, the body is depleted of its main source of energy. With the right diet and healthy lifestyle, people with diabetes can live long and active lives, avoiding the serious health problems that untreated diabetes can create. 

Diabetes is a condition that prevents the body from properly metabolizing sugar from food and using it as fuel in the body's cells. When you digest food, most of it is broken down into glucose, a type of sugar. The glucose is then transported in the blood to individual cells to burn for energy. Insulin, a hormone made by the pancreas, is needed to get the glucose into the cells - like a key that opens a door.

In healthy people, the body automatically senses how much glucose is in the bloodstream and releases the right amount of insulin. In diabetes, the pancreas doesn't make enough insulin or the cells are resistant to the insulin, or both. As a result, the amount of glucose in the blood climbs too high while the cells starve for energy.

Diabetes is a condition that affects the way the body uses energy in food. People who have diabetes have trouble controlling their blood sugar levels. Common symptoms of diabetes include fatigue, increased thirst and urination, infections and cuts that don't heal, blurred vision, hunger and weight loss.
Emilia Klapp
Nutrition & Dietetics Specialist
Diabetes is a common blood-sugar disorder that occurs when the body has a problem producing or using insulin. Insulin is a hormone produced by the pancreas that regulates the amount of glucose circulating in the blood. With diabetics, the blood-glucose level is elevated, creating a dangerous situation in which the body’s metabolism can be disrupted severely. Chronic fatigue is a common feature of people with diabetes.
Type 1 diabetes, often diagnosed in childhood or early adulthood, is actually an autoimmune disease. Certain cells in the pancreas stop working because the body's immune system has started attacking them. Type 2 diabetes can be diagnosed at any age and may be linked with a higher body mass index (BMI) and less frequent activity. If you have high blood pressure or high cholesterol, your doctor may want to test for Type 2 diabetes.

Diabetes is a disease that affects the way the body uses food. It causes blood glucose levels (blood sugar) to be too high.

Normally, during digestion, the body changes sugars, starches, and other foods into a form of sugar called glucose. Then the blood caries this glucose to cells throughout the body. There, with the help of insulin (a hormone), glucose is changed into quick energy for the cells to use or store for future needs. (Insulin is made in the beta cells of the pancreas, a small organ behind the stomach.) This process of turning food into energy is crucial, because the body depends on food for every action, from pumping blood and thinking to running and jumping.

In diabetes, something goes wrong with the normal process of turning food into energy. Food is changed into glucose readily enough, but there is a problem with insulin. In one type of diabetes, the pancreas cannot make insulin. In another type, the body makes some insulin, but has trouble using the insulin. When insulin is absent or ineffective, the glucose in the bloodstream cannot be used by the cells to make energy. Instead, glucose collects in the blood, eventually leading to the high glucose levels that are the hallmark of untreated diabetes.

Types of Diabetes

  • Type 1 diabetes - used to be called juvenile-onset diabetes because it occurs most often in children and young adults. But the name was changed after doctors realized it could occur at any age. In this form of diabetes, the pancreas stops making insulin or makes only a tiny amount. Insulin is necessary to life, so the hormone must be injected every day.
  • Type 2 diabetes - used to be called adult-onset diabetes because it occurs most often in adults. In type 2 diabetes, the pancreas produces some insulin but it is not used very well.
  • Gestational diabetes - is high blood glucose that first occurs during pregnancy. It usually disappears after the birth of the baby, although most women will develop diabetes (usually type 2) during their lifetime.
  • Prediabetes - means that blood glucose falls between "normal" and "diabetic" levels. People with prediabetes have an increased risk of developing type 2 diabetes and heart problems.
The American Diabetes Association defines diabetes as the inability of the body to change sugar (glucose) from food into energy. This process is regulated by insulin, a hormone produced in the pancreas. There are two major types of diabetes. Type 1 usually begins in childhood and occurs when the body produces little or no insulin. With type 2 diabetes, the body either makes insulin but not enough to meet its needs or the body becomes resistant to the insulin produced.
Diabetes mellitus is a metabolic disorder characterized by high levels of glucose in the blood resulting from defects in insulin production, insulin action or both. Because insulin is needed by the body to convert glucose into energy, these failures result in abnormally high levels of glucose accumulating in the blood and may cause organ damage. Most new diabetes cases in children are type 1 diabetes, but an increasing prevalence of childhood obesity has been occurring, which leads to insulin resistance and type 2 diabetes.

Diabetes is a serious illness. It happens when you don't have enough insulin -- or when your body doesn't use insulin well. Insulin's job is to change glucose (sugar) from food into energy. If it can't do this, sugar builds up in your blood. You have high blood sugar.

There are two types of diabetes. Type 2 is the most common type. It happens most often in adults who are overweight. Type 1 is less common. It happens more in children and teens.

Caring for diabetes means controlling your blood sugar, blood pressure, and cholesterol. That's because if you have diabetes, you probably have high blood pressure and high cholesterol too. You have a bigger chance for heart attack and stroke. You can also have eye, kidney, and foot problems.

Diabetes has no cure. But you can still live a good, active life. You just have to make healthy choices every day.

Dr. Laura C. Fine, MD
Ophthalmologist (Eye Specialist)
The most common forms of diabetes are designated as type 1 and type 2. In type 1 diabetes, an autoimmune disease, the pancreas is unable to produce insulin, which cells need in order to use blood sugar (glucose). Type 2 diabetes usually develops when people become overweight and their cells fail to respond properly to insulin, so that they are unable to metabolize blood sugar. While the mechanisms that cause type 1 and type 2 diabetes differ, both disorders result in high blood sugar levels which, left untreated, have serious long-term consequences on other parts of the body, including the eyes.

Diabetes is a condition in which the body can no longer regulate blood sugar levels, resulting in an unhealthy buildup of glucose (sugar) in the bloodstream. High blood glucose may not cause immediate, noticeable symptoms, but over time, it can damage blood vessels and lead to serious complications, including heart disease, kidney problems, nerve damage, and blindness. That's why the main goal in managing diabetes is to keep blood sugar levels as close to healthy as possible.

Your body converts carbohydrates from the foods you eat into a simple sugar called glucose—your body's main source of fuel. During digestion, the glucose is passed into your bloodstream, causing your blood glucose level to rise. Normally, this triggers the release of insulin—a hormone produced by your pancreas -- which helps move extra glucose out of your bloodstream and into your cells, where it's used for energy. In people with diabetes, however, this is where the system breaks down because there's no insulin or not enough insulin, or because cells have become resistant to insulin.

Diabetes mellitus, usually called diabetes, is a disease in which your body does not make enough insulin or cannot use normal amounts of insulin properly. Insulin is a hormone that regulates the amount of sugar in your blood. A high blood sugar level can cause problems in many parts of your body.
Diabetes affects the body’s ability to produce or use insulin, a hormone made by the pancreas that tells cells to take in glucose (blood sugar) for energy. Uncontrolled diabetes increases glucose in the bloodstream and upsets normal body functions. When blood sugar remains high, it may damage organs, such as eyes, kidneys, heart and limbs.
Jessica Crandall
Nutrition & Dietetics Specialist

Diabetes stems from the Greek word "running through" Mellitus Greek word for "sweet". The body is unable to produce enough insulin or get rid of the sugar in the blood stream which causes an elevated blood sugar. It can be managed through diet, exercise, behavior modification and medication. However it is important to make sure you seek medical advice upon diagnosis so that the disease can be managed and progression can be slowed.


Dr. Scott C. Makemson, MD
OBGYN (Obstetrician & Gynecologist)

Diabetes is a condition in which the body doesn't produce the right amount of insulin, the hormone that allows cells to absorb glucose (sugar) from the bloodstream. Some people with diabetes must inject themselves with insulin every day to maintain a healthy glucose level. Others are able to control the condition with pills or a special diet.

Diabetes is a syndrome characterized by disordered metabolism and abnormally high blood sugar resulting from an insufficiency of the hormone insulin. The characteristic symptoms are excessive urine production due to high blood-glucose levels, excessive thirst, increased fluid uptake, unexplained weight loss, and lethargy.
Dr. Kelly Traver

Diabetes is a condition in which you have a higher-than-normal blood sugar level (also called blood glucose level) in your bloodstream. You are diagnosed as having diabetes if your blood sugar level is over 125 mg/dl after you have been without food for 12 hours. You are diagnosed as having prediabetes if your blood sugar range is 100 to 125 mg/dl. An elevated blood sugar level is harmful to all of the arteries in your body; so, over time, if your blood sugar level remains elevated, the organs in your body will start to malfunction and die. This can lead to heart attacks, strokes, kidney failure, and blindness.

A high blood sugar level is also toxic to your nerves and immune cells and can cause painful, numb extremities; bowel and bladder problems; difficulty with erections if you are a man; poor wound healing; and frequent infections.

Tonya Bolden
Alternative & Complementary Medicine Specialist

Diabetes is a disorder of metabolism - the way our bodies use digested food for growth and energy. Most of the food we eat is broken down into glucose, the form of sugar in the blood. Glucose is the main source of fuel for the body.

After digestion, glucose passes into the bloodstream, where it is used by cells for growth and energy. For glucose to get into cells, insulin must be present. Insulin is a hormone produced by the pancreas, a large gland behind the stomach.

When we eat, the pancreas automatically produces the right amount of insulin to move glucose from blood into our cells. In people with diabetes, however, the pancreas either produces little or no insulin, or the cells do not respond appropriately to the insulin that is produced. Glucose builds up in the blood, overflows into the urine, and passes out of the body. Thus, the body loses its main source of fuel even though the blood contains large amounts of glucose.
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When the pancreas doesn't produce the insulin it should, you develop diabetes.

Watch the video to learn more from Dr. Oz about diabetes.

Stacy Wiegman, PharmD
Pharmacy Specialist
Diabetes is a disease of metabolism in which the levels of sugar (glucose) in your blood are too high. Most of the food you eat is broken down into glucose in your body. After digestion, the glucose enters your blood and eventually, with the help of the hormone insulin, is used by your body's cells for energy.

In people who do not have diabetes, the pancreas makes the right amount of insulin to move glucose from the blood into cells throughout your body. But in people with diabetes, the pancreas either produces no insulin or too little insulin, or the body's cells do not respond normally to the insulin. The glucose builds up in the blood and is excreted from the body in the urine without being used by the body for fuel. Symptoms of diabetes include thirst, weight loss, fatigue and frequent urination. Over time, diabetes can damage eyes, nerves and kidneys. Diabetes also raises your risks for cardiovascular disease. Consult your doctor for more information about diabetes.
Diabetes is a common, chronic disorder marked by elevated levels of blood glucose, or sugar. It occurs when your cells don't respond appropriately to insulin (a hormone secreted by the pancreas), and when your pancreas can't produce more insulin in response. Diabetes usually can't be cured. Left untreated -- or poorly managed -- it can lead to serious long-term complications, including kidney failure, amputation, and blindness. Moreover, having diabetes increases your risk for cardiovascular disease, including heart attack and stroke.
Dr. Michael T. Murray, ND
Naturopathic Medicine Specialist

Diabetes mellitus is a chronic disorder of carbohydrate, fat, and protein metabolism characterized by fasting elevations of blood sugar (glucose) levels and a greatly increased risk of heart disease, stroke, kidney disease, retinopathy, and loss of nerve function. Diabetes can occur when the pancreas does not secrete enough insulin or when the cells of the body become resistant to insulin. In either case, the blood sugar cannot get into the cells for storage, which then leads to serious complications.

Diabetes is divided into two major categories: type 1 and type 2. Type 1, or insulin dependent, diabetes mellitus occurs most often in children and adolescents and is associated with complete destruction of the beta cells of the pancreas, which manufacture the hormone insulin. Type 1 diabetics require lifelong insulin for the control of blood sugar levels. Type 2, or non-insulin-dependent, diabetes mellitus (NIDDM), usually has an onset after 40 years of age, although the incidence of type 2 diabetes in children and adolescents has increased dramatically in the last decade. About 90 percent of all diabetics are type 2. Initially, their insulin levels are typically elevated, indicating a loss of sensitivity to insulin by the cells of the body, otherwise known as insulin resistance.

Other types of diabetes include:

  • Secondary diabetes, which is a form of diabetes that is secondary to other conditions, such as pancreatic disease, hormone disturbances, medication use, and malnutrition.
  • Gestational diabetes, which is a form of glucose intolerance that occurs during pregnancy.
  • Impaired glucose tolerance, which is a condition that includes prediabetic or borderline diabetes. Individuals with impaired glucose tolerance have blood glucose levels and glucose tolerance test (GTT) results that are intermediate between normal and clearly abnormal.
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Diabetes is a condition in which the body cannot change sugars and starches (carbohydrates) into energy. This happens when the body cannot make enough insulin or cannot use the insulin it makes. As a result, extra sugar in the blood can lead to damage in the blood vessels, eyes, kidneys, heart, and nerves.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.