Diabetes Glossary

A blood test that measures your average blood sugar level over the past 2 to 3 months. It reflects the percentage of hemoglobin proteins coated with sugar. A normal A1C is below 5.7%, prediabetes is 5.7-6.4%, and diabetes is 6.5% or higher.

A skin condition that causes dark, velvety patches in body folds and creases, often on the neck, armpits, or groin. It is commonly associated with insulin resistance and can be an early sign of Type 2 diabetes.

A protein found in blood. When found in urine (albuminuria), it may indicate kidney damage caused by diabetes. Regular urine albumin tests help detect diabetic nephropathy early.

Cells in the pancreas that produce glucagon, a hormone that raises blood sugar levels. In diabetes, alpha cell function may be disrupted, contributing to blood sugar imbalances.

A condition where the body's immune system mistakenly attacks its own cells. Type 1 diabetes is an autoimmune disease in which the immune system destroys the insulin-producing beta cells in the pancreas.

Long-acting insulin that provides a steady, low level of insulin throughout the day and night to manage blood sugar between meals and during sleep. It mimics the background insulin your pancreas normally produces.

Cells located in the islets of Langerhans in the pancreas that produce and release insulin. In Type 1 diabetes, these cells are destroyed by the immune system; in Type 2, they may become dysfunctional over time.

A small portable device used to measure the amount of glucose (sugar) in a drop of blood, usually obtained by pricking a fingertip. Also called a glucometer, it helps people with diabetes monitor their daily blood sugar levels.

The main sugar found in the blood and the body's primary source of energy. It comes from the food you eat, particularly carbohydrates. Maintaining blood sugar within a healthy range is the central goal of diabetes management.

A number calculated from your weight and height that is used as a screening tool for overweight and obesity. A BMI of 25-29.9 is overweight and 30+ is obese. Higher BMI increases the risk of Type 2 diabetes.

Rapid-acting or short-acting insulin taken at mealtimes to manage the blood sugar spike caused by eating. The dose is calculated based on the carbohydrate content of the meal.

A meal-planning method where you track the grams of carbohydrate in your food to help manage blood sugar levels. It is especially important for people using insulin, as it helps determine the correct dose.

A group of conditions affecting the heart and blood vessels, including heart attack and stroke. People with diabetes have a 2 to 4 times higher risk of cardiovascular disease, making heart health a critical part of diabetes management.

A waxy, fat-like substance found in your blood. High LDL ("bad") cholesterol increases heart disease risk, which is already elevated in diabetes. Managing cholesterol through diet and medication is a key part of diabetes care.

A wearable device that tracks blood sugar levels continuously throughout the day and night using a tiny sensor inserted under the skin. It provides real-time readings and alerts for highs and lows, reducing the need for finger-prick tests.

A substance produced by the pancreas alongside insulin. Measuring C-peptide levels helps doctors determine how much insulin your body is still making, which aids in distinguishing between Type 1 and Type 2 diabetes.

A natural rise in blood sugar that occurs in the early morning hours (typically between 4 a.m. and 8 a.m.) due to the release of hormones like cortisol and growth hormone. It can cause higher-than-expected fasting blood sugar readings.

The emotional burden and stress that comes from living with and managing diabetes on a daily basis. It differs from clinical depression and includes feelings of overwhelm, frustration, and burnout related to diabetes care.

A healthcare professional, often a nurse or dietitian, who specializes in teaching people with diabetes how to manage their condition. Certified Diabetes Care and Education Specialists (CDCES) provide guidance on diet, medication, monitoring, and lifestyle.

A serious, potentially life-threatening complication where the body produces high levels of ketones due to severe insulin deficiency. It occurs most often in Type 1 diabetes and requires immediate medical treatment.

Eye damage caused by high blood sugar levels over time, which harms the tiny blood vessels in the retina. It is a leading cause of blindness in adults and can be prevented or slowed with good blood sugar control and regular eye exams.

A doctor who specializes in the endocrine system, which includes the glands and hormones that control metabolism. Endocrinologists often manage complex diabetes cases, especially those requiring insulin therapy.

A blood sugar measurement taken after not eating or drinking anything (except water) for at least 8 hours. A normal fasting glucose is below 100 mg/dL, prediabetes is 100-125 mg/dL, and diabetes is 126 mg/dL or higher.

A type of carbohydrate that the body cannot digest. It slows the absorption of sugar and improves blood sugar control. High-fiber foods like vegetables, whole grains, and legumes are especially beneficial for people with diabetes.

The practice of inspecting and caring for the feet to prevent complications from diabetic neuropathy and poor circulation. Diabetes can reduce sensation in the feet, making it harder to notice injuries that may lead to serious infections.

A natural sugar found in fruits, honey, and some vegetables. While it has a lower glycemic index than table sugar, excessive fructose consumption (especially from processed sources) can worsen insulin resistance and raise triglycerides.

A condition where the stomach takes too long to empty its contents, caused by nerve damage from prolonged high blood sugar. It can make blood sugar levels unpredictable and cause nausea, vomiting, and bloating.

Diabetes that develops during pregnancy in women who did not previously have diabetes. It usually resolves after delivery, but it increases the risk of developing Type 2 diabetes later in life for both mother and child.

A class of injectable or oral medications (like semaglutide and liraglutide) that mimic a natural gut hormone to stimulate insulin release, reduce appetite, and slow digestion. They are used for Type 2 diabetes and weight management.

A hormone produced by alpha cells in the pancreas that raises blood sugar by signaling the liver to release stored glucose. Glucagon emergency kits are used to treat severe hypoglycemia when a person cannot eat or drink.

A simple sugar that is the body's main source of energy. It comes from digesting carbohydrates and is carried through the bloodstream to cells. Insulin is needed to move glucose from the blood into cells for energy.

The degree of fluctuation in blood sugar levels throughout the day. Large swings between highs and lows can be harmful even if the average blood sugar (A1C) appears normal. Reducing variability is a key goal of modern diabetes management.

A ranking system from 0 to 100 that measures how quickly a carbohydrate-containing food raises blood sugar after eating. Low-GI foods (55 or below) cause a slow, gradual rise, while high-GI foods (70+) cause rapid spikes.

A more accurate measure than glycemic index alone, as it accounts for both the GI of a food and the amount of carbohydrate in a typical serving. A GL of 10 or less is low, 11-19 is medium, and 20+ is high.

The stored form of glucose found primarily in the liver and muscles. When blood sugar drops, the body converts glycogen back into glucose for energy. People with diabetes may have impaired glycogen regulation.

High-density lipoprotein, often called "good" cholesterol because it helps remove other forms of cholesterol from the bloodstream. People with diabetes often have low HDL levels, and raising HDL through exercise and diet is beneficial.

A protein in red blood cells that carries oxygen throughout the body. The A1C test measures how much glucose has attached to hemoglobin over time, providing a 2-3 month average of blood sugar levels.

Abnormally high blood sugar, generally above 180 mg/dL after meals or above 130 mg/dL when fasting. Symptoms include frequent urination, increased thirst, blurred vision, and fatigue. Chronic hyperglycemia leads to long-term diabetes complications.

A condition where blood pressure is consistently too high (above 130/80 mmHg). It commonly occurs alongside diabetes and significantly increases the risk of heart disease, stroke, and kidney damage.

Abnormally low blood sugar, typically below 70 mg/dL. Symptoms include shakiness, sweating, confusion, rapid heartbeat, and irritability. Severe hypoglycemia can lead to seizures or loss of consciousness and requires immediate treatment with fast-acting sugar.

A group of gut hormones (including GLP-1 and GIP) that stimulate insulin secretion after eating. They also slow stomach emptying and reduce appetite. Incretin-based medications are a major class of Type 2 diabetes drugs.

A hormone produced by beta cells in the pancreas that allows glucose to enter cells for energy. Without enough insulin or when the body cannot use it effectively, blood sugar builds up in the blood, leading to diabetes.

A device shaped like a pen used to inject insulin. It contains a prefilled cartridge of insulin and a disposable needle tip, making it more convenient and precise than traditional syringes for many people.

A small computerized device that delivers rapid-acting insulin continuously through a tiny tube (cannula) placed under the skin. It mimics a healthy pancreas by providing basal insulin and bolus doses at mealtimes.

A condition where the body's cells do not respond effectively to insulin, requiring the pancreas to produce more insulin to keep blood sugar normal. It is the primary driver of Type 2 diabetes and is strongly linked to excess body weight and inactivity.

The amount of rapid-acting insulin needed to cover a specific number of carbohydrate grams (e.g., 1 unit per 10g carbs). It is used by people on insulin therapy to calculate mealtime doses accurately.

Clusters of cells in the pancreas that contain alpha cells (producing glucagon) and beta cells (producing insulin). They are the key hormone-producing units of the pancreas and are damaged in Type 1 diabetes.

Chemicals produced when the body burns fat for energy instead of glucose. Moderately elevated ketones can occur during fasting or low-carb diets. Dangerously high levels indicate diabetic ketoacidosis, a medical emergency.

A small, sharp needle used to prick the skin (usually a fingertip) to obtain a drop of blood for glucose testing. Lancets are spring-loaded and disposable, designed to minimize pain.

A slow-progressing form of autoimmune diabetes that develops in adulthood, sometimes called Type 1.5 diabetes. Unlike typical Type 1, LADA patients may not need insulin immediately but will eventually require it as their beta cells are gradually destroyed.

Low-density lipoprotein, often called "bad" cholesterol because high levels contribute to plaque buildup in arteries, increasing heart attack and stroke risk. People with diabetes should aim for LDL below 100 mg/dL.

Abnormal changes in fat tissue at insulin injection sites, causing lumps (lipohypertrophy) or dents (lipoatrophy) under the skin. Rotating injection sites can help prevent this common complication of insulin therapy.

Diabetes-related damage to large blood vessels, leading to conditions like coronary artery disease, stroke, and peripheral arterial disease. Good blood sugar, blood pressure, and cholesterol control reduces these risks.

A cluster of conditions occurring together — high blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels — that dramatically increase the risk of heart disease, stroke, and Type 2 diabetes.

The most commonly prescribed first-line medication for Type 2 diabetes. It works by reducing glucose production in the liver and improving insulin sensitivity. It is generally well-tolerated and may also help with weight management.

The presence of small amounts of the protein albumin in urine, which is an early sign of kidney damage. Annual screening for microalbuminuria is recommended for all people with diabetes.

Diabetes-related damage to small blood vessels, leading to problems in the eyes (retinopathy), kidneys (nephropathy), and nerves (neuropathy). These are the most common long-term complications of diabetes.

Kidney damage or disease caused by diabetes. High blood sugar over time damages the tiny filtering units of the kidneys, potentially leading to kidney failure. Controlling blood sugar and blood pressure are the best ways to prevent or slow it.

The total grams of carbohydrate in a food minus the grams of fiber and sugar alcohols. Net carbs represent the carbohydrates that significantly impact blood sugar. This concept is commonly used in low-carb diets for diabetes management.

Nerve damage caused by prolonged high blood sugar. The most common form, peripheral neuropathy, affects the feet and hands, causing tingling, numbness, or pain. Autonomic neuropathy affects internal organs and can impact digestion and heart rate.

A condition defined by a BMI of 30 or higher, characterized by excessive body fat. It is the single strongest risk factor for Type 2 diabetes, as excess fat — especially around the abdomen — increases insulin resistance.

A diagnostic test where you drink a sugary solution, and blood sugar is measured at intervals (usually at 1 and 2 hours) to see how your body processes glucose. It is commonly used to diagnose gestational diabetes and prediabetes.

An organ located behind the stomach that produces insulin and glucagon to regulate blood sugar, as well as enzymes for digestion. Dysfunction of the pancreas is at the core of both Type 1 and Type 2 diabetes.

A circulatory condition in which narrowed blood vessels reduce blood flow to the limbs, especially the legs and feet. People with diabetes are at higher risk, and PVD can contribute to slow-healing wounds and, in severe cases, amputation.

Excessive thirst, which is one of the classic early symptoms of undiagnosed or uncontrolled diabetes. It occurs because high blood sugar causes the body to pull fluid from tissues, triggering a persistent feeling of thirst.

Excessive hunger, one of the three classic symptoms of diabetes (along with polydipsia and polyuria). It occurs because the body's cells are starved for energy when glucose cannot enter them without sufficient insulin.

Frequent or excessive urination, another hallmark symptom of diabetes. When blood sugar is high, the kidneys work to filter out the excess glucose, producing more urine and leading to dehydration.

The practice of eating measured amounts of food to help manage calorie and carbohydrate intake. For people with diabetes, portion control is one of the most effective and simplest strategies for keeping blood sugar stable after meals.

Blood sugar measured after eating, typically 1 to 2 hours after a meal. A postprandial reading below 180 mg/dL is the general target for most people with diabetes. Post-meal spikes are a key focus of diabetes management.

A condition where blood sugar levels are higher than normal but not yet high enough for a Type 2 diabetes diagnosis (A1C 5.7-6.4% or fasting glucose 100-125 mg/dL). Without intervention, most people with prediabetes develop diabetes within 10 years.

A simple meal-planning approach where you visually divide your plate: half with non-starchy vegetables, one quarter with lean protein, and one quarter with whole grains or starchy foods. It helps control portions and balance blood sugar without counting carbs.

Insulin that starts working within 15 minutes of injection, peaks in about 1 hour, and lasts 2 to 4 hours. It is taken just before or with meals to manage post-meal blood sugar spikes. Examples include insulin lispro and insulin aspart.

A licensed nutrition professional who can create personalized meal plans for people with diabetes. Working with an RD is one of the most effective ways to improve blood sugar control through diet.

The blood sugar level (typically around 180 mg/dL) at which the kidneys begin to filter excess glucose into the urine. When blood sugar exceeds this threshold, glucose spills into the urine, a condition called glycosuria.

A class of oral diabetes medications (like empagliflozin and dapagliflozin) that lower blood sugar by blocking the kidneys from reabsorbing glucose, causing excess sugar to be excreted in urine. They also offer heart and kidney protective benefits.

The practice of regularly testing your own blood sugar levels using a blood glucose meter. It helps people with diabetes make informed decisions about food, exercise, and medication throughout the day.

A rebound high blood sugar in the morning caused by the body's response to overnight low blood sugar (hypoglycemia). The body releases stress hormones that trigger glucose release from the liver. It is sometimes confused with the dawn phenomenon.

Foods high in complex carbohydrates such as bread, rice, pasta, potatoes, and corn. They have a significant impact on blood sugar and need to be eaten in controlled portions as part of a diabetes meal plan.

Table sugar, made up of one glucose molecule and one fructose molecule. It has a moderate glycemic index and should be consumed sparingly by people with diabetes. Reading food labels helps identify hidden sucrose in packaged foods.

Low-calorie sweeteners (like xylitol, erythritol, and sorbitol) that are partially absorbed by the body and have less impact on blood sugar than regular sugar. They are commonly used in sugar-free products and may cause digestive issues in large amounts.

A class of oral diabetes medications that stimulate the pancreas to produce more insulin. They are effective at lowering blood sugar but carry a risk of causing hypoglycemia and weight gain.

The percentage of time blood sugar stays within a target range, usually 70-180 mg/dL. It is an increasingly important metric alongside A1C, often tracked by continuous glucose monitors. A TIR of 70% or higher is the general goal.

A type of fat in the blood that provides energy to cells. High triglyceride levels (above 150 mg/dL) are common in people with poorly controlled diabetes and increase the risk of heart disease and pancreatitis.

An autoimmune condition where the immune system destroys the insulin-producing beta cells of the pancreas. It typically develops in childhood or young adulthood and requires lifelong insulin therapy. It accounts for about 5-10% of all diabetes cases.

The most common form of diabetes, accounting for about 90-95% of cases. The body either does not produce enough insulin or cannot use it effectively (insulin resistance). It is strongly linked to lifestyle factors, and T2D can often be managed — and some people achieve remission — through diet, exercise, and medical care. Individual results vary. Discuss any changes with your healthcare team.

An open sore or wound, most commonly on the feet, that develops due to poor circulation and nerve damage from diabetes. Diabetic foot ulcers can become seriously infected if not treated promptly and are a leading cause of lower-limb amputation.

The standard measurement for insulin dosing. One unit of rapid-acting insulin typically lowers blood sugar by 30-50 mg/dL in most adults, though individual sensitivity varies. Precise dosing is critical for safe blood sugar management.

Any condition that affects the blood vessels, including arteries, veins, and capillaries. Diabetes accelerates vascular disease, which is why heart attack, stroke, and poor circulation in the extremities are major concerns for people with diabetes.

Fat stored deep within the abdominal cavity around internal organs. Unlike subcutaneous fat under the skin, visceral fat is metabolically active and strongly linked to insulin resistance, Type 2 diabetes, and cardiovascular disease.

The process of maintaining a healthy body weight through balanced eating and regular physical activity. Even a modest weight loss of 5-7% of body weight can significantly improve insulin resistance and blood sugar control in people with Type 2 diabetes.

Grains that contain all three parts of the kernel (bran, germ, and endosperm), such as brown rice, oats, quinoa, and whole wheat. They are digested more slowly than refined grains, causing a gentler rise in blood sugar and providing more fiber and nutrients.