What Is Diabetes?
Updated By Kim Ladd, RN, BS, CPHQ, CDCES and Audrey Demmitt, RN, BSN, March 2021
s of Diabetes
- A metabolic disorder
- A chronic, progressive disease
- A growing public health concern.
Diabetes mellitus (usually referred to as diabetes) is defined as a chronic disorder of carbohydrate metabolism resulting from inadequate production or utilization of the hormone insulin. When a person has diabetes, their pancreas either doesn’t make enough insulin or their body can’t use its own insulin effectively.
Diabetes is characterized by a high level of glucose in the bloodstream, also known as hyperglycemia. Glucose is the principle circulating sugar in the blood and is the first source of energy to all cells in the body.
Cells cannot use glucose, however, without the help of insulin. Insulin is a hormone produced by the pancreas which helps move glucose out of the bloodstream into cells where it is used for energy to fuel everyday activities.
Diabetes occurs when
- the pancreas does not make or release enough insulin,
- the body’s cells are resistant to insulin, or
- both conditions are present.
Diabetes is a Metabolic Disorder
Metabolism is a term that describes the processes through which food is converted into energy for your body to use immediately or store for later use.
In normal food metabolism:
- The food you eat is broken down into glucose and other simple sugars and enters your bloodstream.
- Your body senses the rise in blood glucose and signals your pancreas to release insulin into your bloodstream.
- The released insulin acts as a “key” that unlocks your cells and allows glucose to enter.
- Your cells absorb glucose to provide energy for physical activity.
The foods you eat that break down into glucose are called carbohydrates, which:
- are one of the three main nutrients in food, in addition to proteins and fats
- include sugars and starches contained in fruit; breads and cereals; milk and dairy; starchy vegetables such as corn, potatoes, and peas; cake and ice cream
- cause blood glucose levels to rise about one to two hours after a meal
- determine how high or low your blood glucose levels will go, according to the type and amount of carbohydrate-containing foods you eat.
When this process occurs as it should, the glucose level in your bloodstream remains within a normal range of 70 to 100 milligrams per deciliter (mg/dL). In diabetes, however, this process does not occur properly, which results in a serious, lifelong metabolic disorder.
There Are Different Types of Diabetes
Type 1 diabetes (formerly called juvenile-onset, Type I, or insulin dependent) has the following characteristics:
- It usually occurs before age 30 and affects about 5% of individuals with diabetes.
- It occurs when the body produces little to no insulin. (insulin deficiency)
- Glucose levels continue to rise in the bloodstream because it cannot enter the body’s cells.
- Type 1 occurs when the body’s immune system destroys its own insulin-producing cells in the pancreas, for reasons that are not yet clear to researchers. Possible reasons include genetic factors, viruses, or a defect in the body’s autoimmune system.
- Risk factors for developing type 1 diabetes include: having a parent, brother, or sister with type 1 diabetes and ethnicity. Caucasians are more likely to develop type 1 diabetes than African Americans and Hispanic/Latino Americans.
- Insulin shots are required to sustain life.
Type 2 diabetes (formerly called adult-onset, Type II, or non-insulin dependent) has the following characteristics:
- It is the most common type of diabetes. It usually occurs after age 30 and affects 90%-95% of individuals with diabetes.
- It begins with insulin resistance (prediabetes) – a condition that occurs when fat, muscle, and liver cells do not use insulin to carry glucose into their cells to use for energy. In response to this, the body produces more insulin to help glucose enter cells. At first, the pancreas keeps up with the added demand by making more insulin. However, over time, the pancreas wears out and can no longer make enough insulin when blood glucose levels increase, such as after meals. Blood glucose levels will continue to climb when cells cannot use the glucose they need. If your pancreas can no longer make enough insulin, you will need to treat your type 2 diabetes.
- It can be managed initially with weight loss, physical activity, and effective meal planning and for some individuals this works for a period of time. When the disease progresses, however, oral medication, injectable medications or insulin may also be required.
- The exact cause of type 2 diabetes is still unknown. However, there is a genetic factor (meaning it runs in families) and known risk factors that put you at risk for developing type 2 diabetes. The risk factors include increasing age (45+), ethnic background (African-American, Latino, Native American, Asian) poor eating habits; lack of physical activity; certain medications and illnesses; and obesity.
- Develops in the 24th- 26th week of pregnancy
- Pregnant women make hormones that can lead to insulin resistance. All women have insulin resistance late in their pregnancy, but if the pancreas doesn’t make enough insulin during pregnancy, a woman develops gestational diabetes.
- Usually goes away after the birth of the baby
- Greatly increases the mother’s chance of developing Type 2 diabetes later in life
Other Types of Diabetes
- Account for about 1% of diabetes cases
- Occur as a result of specific genetic syndromes, surgery, drugs, malnutrition, infections, and other illnesses
- LADA (Latent Autoimmune Diabetes in Adults)
- Neonatal diabetes
- MODY (Maturity Onset Diabetes in the Young)
Diabetes Is a Chronic, Progressive Disease
- Diabetes is a condition that is treatable but not curable.
- There is no such condition as “having a little bit of sugar” or “a touch of sugar.” An individual either has diabetes or does not.
- There is, however, a condition called prediabetes in which blood glucose levels are higher than normal but are not yet high enough to be diagnosed as diabetes.
- Individuals with prediabetes have a significant risk for progressing to diabetes, and an elevated risk for heart disease and stroke.
- An individual can be diagnosed with diabetes if he or she has classic symptoms of high blood glucose – excessive thirst, frequent urination, increased appetite, unexplained weight loss, and has a blood glucose level of 200 mg/dL or greater on a Random Plasma Glucose Test (RPG).
- Several other tests can diagnose both diabetes and pre-diabetes: (a) the Fasting Plasma Glucose Test (FPG), (b) the 2-Hour Oral Glucose Tolerance Test (OGTT), and (c) glycated hemoglobin (A1C).
- The FPG is used more frequently. When your doctor prescribes blood work and tells you not to eat the night before, he or she is probably checking for diabetes or pre-diabetes by using the FPG test.
- An FPG test that reports blood glucose levels between 100 mg/dL and 125 mg/dL indicates prediabetes. Diabetes is present when the result is 126 mg/dL or greater. A repeat test will confirm the results.
- Hemoglobin A1C can be measured without fasting. This test measures your average blood glucose control for the past 2 to 3 months. A level between 5.7% and 6.4% suggests an increased risk of developing diabetes; a level greater than or equal to 6.5% indicates diabetes.
Comparison Between A1C and Average Blood Glucose Level:
|Normal||below 5.7 percent|
|Pre-diabetes||5.7 to 6.4 percent|
|Diabetes||6.5 percent or above|
Diabetes Is a Growing Public Health Concern
- According to the Centers for Disease Control (CDC) 2020 National Diabetes Statistics Report
- 34.2 million people have diabetes (10.5% of the US population)
- 88 million people aged 18 years or older have prediabetes (34.5% of the adult US population)
- 24.2 million people aged 65 years or older have prediabetes
- Type 2 diabetes is becoming more prevalent in children, due to poor eating habits and lack of exercise.
- Diabetes is the 7th leading cause of death in the United States.
- Diabetes retinopathy is the number 1 cause of blindness in adults.
- According to the NIH National Eye Institute, from 2010 to 2050, the number of Americans with diabetic retinopathy is expected to nearly double, from 7.7 million to 14.6 million. Hispanic Americans are expected to see the greatest increase in cases, rising more than three-fold from 1.2 million to 5.3 million.
- Diabetes is the leading cause of kidney disease. About 1 out of 3 adults with diabetes has kidney disease, according to the NIH National Institute of Diabetes and Digestive and Kidney Diseases.
- Medical costs for people with diabetes are twice as high as for people who don’t have diabetes.
- Medical costs and lost work and wages for people with diagnosed diabetes total $327 billion yearly, according to the CDC.