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Definitions and vocabulary

Definitions and vocabulary

Diabetes described:
a glossary of terms

This glossary defines key diabetes terms so you can have more meaningful discussions with your healthcare team.


Unsure of a medical term? Look it up here.

Adult-onset diabetes

The former term for type 2 diabetes. Although type 2 diabetes usually occurs in people over 40, this term is no longer used because the disease is being increasingly diagnosed in younger people, even adolescents and children.

A1C (or glycosylated hemoglobin A1C)

A measure of the blood glucose levels over the previous 120 days. People living with diabetes should have their A1C measured approximately every three months.

Acanthosis nigricans

A skin disorder in which dark patches of skin and “velvety” thickening of the skin appear, especially in the neck, groin and under the arms. It may be a sign of insulin resistance and is common in children with type 2 diabetes.


A protein produced by the body to fight off foreign substances such as bacteria, allergens, viruses and transplanted tissues or organs.

Autoimmune disease

A disorder in which a person’s own antibodies destroy the body’s tissues. Type 1 diabetes is an autoimmune disease, in which the body’s own cells destroy the beta cells in the pancreas.

Basal insulin

The insulin that controls blood glucose levels between meals and overnight. It controls glucose in the fasting state.

Beta cells

Insulin-producing cells found in the pancreas.

Blood glucose (or glucose)

The concentration of glucose in the blood. Blood glucose is measured in mmol of glucose per litre of blood (mmol/L). The recommended range for a person living with diabetes before meals is 4-7 mmol/L, while the recommended range two hours after a meal is 5-10 mmol/L.

Body mass index (BMI)

The unit of measurement to describe weight in relation to height for people 20 to 65 years of age. It is calculated by taking a person’s weight (in kilograms) and dividing by their height squared (kg/m2). It is used to classify people as underweight, normal weight, overweight, or obese.

Bolus insulin

A bolus is a burst of insulin that is delivered by injection or by the insulin pump to “cover” a meal or snack or to correct for a high blood glucose level.


One of the main sources of calories. Sources of carbohydrates include sugars naturally found in honey, fruits, vegetables and milk; refined sugars such as table sugar and sugars added to candies, jams and soft drinks; and starches such as grains, rice, potatoes, corn and legumes. Carbohydrates are broken down into glucose during digestion.

Carbohydrate counting

A method of meal planning for people living with diabetes based on counting the number of grams of carbohydrates in food.


A medical doctor who specializes in the study, care and treatment of the heart.

Cardiovascular system

The system of blood vessels, veins and arteries that delivers blood to all the tissues and organs in the body, including the heart and brain. The bloodstream carries nutrients (such as glucose) and oxygen to the cells and removes waste products.

Conventional insulin therapy

An insulin therapy in which the insulin regimen is decided first and the person living with diabetes has to eat and engage in physical activity according to the timed actions of the insulin injections.


A compound present in the muscles and blood that is removed from the body in the urine.

Diabetes educator

A healthcare professional trained to teach patients about diabetes and how to make adjustments to diabetes treatments. He or she may also be trained as a nurse, dietitian, pharmacist, psychologist or other healthcare professional.


A medical doctor who specializes in diseases of the endocrine system (system of glands in the body that produce hormones).


The study of the occurrence, distribution and causes of diseases in humans.

Fasting blood glucose test

A blood test in which a sample of blood is measured for glucose content after the individual has not eaten for several hours. A test result of 7.0 mmol/L or greater, after at least 8 hours of fasting, indicates diabetes.

Gestational diabetes mellitus (GDM)

Diabetes that is first diagnosed or first develops during pregnancy. It affects 2% to 4% of all pregnancies. Blood glucose levels usually return to normal after delivery. Both mother and child are at higher risk of developing type 2 diabetes later in life.

Glucose meter (or blood glucose meter)

A hand-held machine designed to test blood glucose levels. A drop of blood (usually from the fingertip) is placed on a small test strip that is inserted into the meter. The meter displays the amount of glucose in the blood. Glucose meters allow people living with diabetes to play an active role in monitoring and managing their own blood glucose levels.

Glucose tolerance test

A blood test done every hour or at the 2-hour point after drinking a sugar-filled liquid. This is one test used to diagnose diabetes. A test result of 11.1 mmol/L or greater, taken two hours after having the sweet drink, indicates diabetes.

Glycemic index (GI)

A scale that ranks carbohydrate-rich foods by how much they raise blood glucose levels.

Glycemic load (GL)

A system of ranking carbohydrate foods based on how much they raise blood glucose levels. It combines the GI value and the carbohydrate content of an average serving of a food, of a meal, or of a day’s worth of food.


The main form in which carbohydrate is stored in the liver and muscles. It is readily broken down to glucose for use when energy is needed.

High-fructose corn syrup (or glucose-fructose)

A commonly used liquid sweetener made from cornstarch, often used to sweeten beverages and other food products. Also referred to as glucose-fructose on nutrition labels.


Higher-than-normal levels of glucose in the blood. Symptoms may include thirst, frequent urination, blurred vision and fatigue.


High blood pressure.


Lower-than-normal blood glucose. Symptoms may include sweating, trembling, hunger, dizziness, moodiness, confusion, headache, blurred vision and nausea.


A hormone produced by the beta cells of the pancreas that controls the amount of glucose in the blood. Insulin lowers blood glucose by helping move glucose into the body’s cells, where it is used as fuel.

Insulin resistance

A condition in which the body’s cells and tissues do not respond properly to the effects of insulin. It is a key feature of type 2 diabetes.

Insulin pump

A portable, battery-operated device that delivers a specific amount of insulin through a small needle inserted under the skin. It can be programmed to deliver constant doses of insulin throughout the day and/or deliver extra insulin as required. Also called continuous subcutaneous insulin infusion (CSII).

Insulin-to-carbohydrate ratio

A method of determining how much rapid-acting insulin is needed to cover the carbohydrate eaten at a meal or snack. This is used as part of a more advanced level of carbohydrate counting.

Intermediate-acting insulin

A type of insulin that begins to work to lower blood glucose within 1 to 4 hours and works hardest 4 to 15 hours after injection.


Products created when fat is broken down to be used for energy. The body normally gets rid of excess ketones in the urine. However, if levels of ketones get too high, they accumulate in the body and can lead to ketoacidosis, coma and even death.


An acute and severe complication of diabetes that is the result of high levels of blood glucose and ketones. It is often associated with poor control of diabetes or occurs as a complication of other illnesses. It can be life-threatening and requires emergency treatment. Signs and symptoms include fruity odour on the breath, shortness of breath, confusion, nausea, vomiting and weight loss.

LDL (low-density lipoprotein)

Particles that carry cholesterol in the blood and around the body for use by cells. LDL-C is commonly known as “bad” cholesterol because high levels of LDL-C lead to increased risk of cardiovascular disease. Because most people living with diabetes are at very high risk of heart disease, it is very important to achieve recommended LDL-C targets (2.0 mmol/L or less for most people with diabetes). This usually requires medication.

Long-acting insulin

A type of insulin that reaches the bloodstream several hours after injection and tends to lower glucose fairly evenly over a 24-hour period.


The sum of all the chemical changes that take place in the body that generate energy and allow tissues and cells to grow, function, use nutrients and eliminate waste.


A medical doctor who specializes in the study, care and treatment of diseases of the kidney.


Any disease of the kidney.


A doctor who specializes in conditions of the nervous system (network of nerve cells and fibres in your body).


Any disease of the peripheral nerves, usually causing numbness and/or weakness and/or pain in the hands and feet.

Nutritive or caloric sweeteners

Sweeteners that contribute calories and can affect blood glucose levels.


Results, impacts or consequences.


An organ in the digestive system that produces several important hormones, including insulin and glucagon. It also produces pancreatic juice containing enzymes that help digestion.


A condition in which a person’s blood glucose level is above normal but not high enough to be considered diabetes. Pre-diabetes has no symptoms and can only be diagnosed with a blood test. It is also called impaired glucose tolerance or impaired fasting glucose. People with pre-diabetes are at high risk of developing type 2 diabetes and cardiovascular disease and should take steps to lower these risks.


One of the major sources of calories in a diet. Found in meats, eggs, milk and some vegetables and starches, protein provides the body with material for building body tissue, blood cells and hormones.

Rapid-acting insulin

A type of insulin that begins to work to lower blood glucose within 10 to 30 minutes and works hardest 30 minutes to 3 hours after injection.

Relative insulin deficiency

A decline in insulin production, which is usually a problem with or without insulin resistance early on in the course of diabetes.

Saturated fat

The “bad” fat found in foods such as butter, lard, coconut oil, dairy products (especially cream and cheese) and meat. A diet that is too high in these fats increases a person’s risk of cardiovascular disease.

Self-monitoring of blood glucose (SMBG)

Blood testing done by a person living with diabetes with a blood glucose meter/monitor to determine how much glucose is in the blood. SMBG helps people with diabetes and their healthcare professionals make decisions about their medications, meal plan and exercise in order to achieve better blood glucose control.

Short-acting insulin

A type of insulin that begins to work to lower blood glucose within 30 to 60 minutes and works hardest 1 to 5 hours after injection.

Subcutaneous fat

The layer of fat that lies just below the skin.

Target heart rate

A heart rate to maintain during aerobic exercise for optimal performance. It is dependent on age, gender, and the intensity of a workout.

Trans fat

One of the four types of fats found in foods. Small amounts of trans fats occur naturally in some foods, but most trans fats are ingredients added to fast foods, prepackaged snack and convenience foods, baked goods and restaurant meals. Trans fats raise LDL (“bad”) cholesterol levels and lower HDL (“good”) cholesterol levels, which increase the risk of heart disease and stroke. Everyone should limit the amount of trans fat they eat.


The main component of vegetable oil and animal fats. In the human body, high levels of triglycerides raise the risk of heart disease and stroke.

Unsaturated fat

The “good” fat found in foods, such as avocado, nuts, and soybean, canola and olive oils. Substituting unsaturated fats for saturated fats helps to lower levels of total cholesterol and LDL (“bad”) cholesterol.

Visceral fat

Deeper layer of fat that surrounds internal organs.

Vitrectomy surgery

A process to remove the blood and scar tissue from within the eye that can frequently restore vision.

Adapted from:

  1. Canadian Diabetes Association.Diabetes Dictionary. Available at:
  2. Joslin Diabetes Center.Diabetes Glossary. Available at:
  3. Mayo Clinic.Women’s Health. Available at:
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