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Type 2 diabetes is a condition in which you have too much sugar (glucose) in your blood. Glucose is a type of sugar produced in your body when carbohydrates and other foods are digested. It provides energy to cells throughout the body.
Normally, blood sugar levels increase after you eat a meal. When blood sugar rises, cells in the pancreas release insulin, which causes the body to absorb sugar from the blood and lowers the blood sugar level to normal.
When you have type 2 diabetes, sugar stays in the blood rather than entering the body's cells to be used for energy. This results in high blood sugar. It happens when your body can't use insulin the right way.
Over time, high blood sugar can harm many parts of the body, such as your eyes, heart, blood vessels, nerves, and kidneys. It can also increase your risk for other health problems (complications).
When your blood sugar stays too high for too long, it causes type 2 diabetes. It happens when your body can't use insulin the right way. Over time, your body cannot make enough insulin.
You may have symptoms of high blood sugar like feeling very thirsty or very hungry. You may also urinate more often than usual, have blurry vision, or lose weight without trying. You're not likely to get symptoms of low blood sugar unless you take insulin or use certain diabetes medicines that lower blood sugar.
If your doctor thinks that you have type 2 diabetes, he or she will order blood tests that measure the amount of sugar in your blood. Blood glucose tests and other tests are used. Your doctor will also ask you questions about your medical history and do a physical exam.
Treatment for type 2 diabetes will change over time. But the focus will be to keep blood sugar levels in your target range. You'll have to make some healthy changes to your daily habits. For example, you may have to watch what you eat, take medicine every day, and watch for other health problems.
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When your blood sugar (glucose) stays too high for too long, it causes type 2 diabetes.
It happens when:
Insulin is a hormone that helps your body use sugar from your food as energy. It also helps your body store extra sugar in muscle, fat, and liver cells. Without insulin, this sugar can't get into your cells to do its work. It stays in your blood instead. This can cause high blood sugar levels.
You're more likely to get type 2 diabetes if you:
Other things that may put you at risk for type 2 diabetes include:footnote 1
Other health problems can put you at risk for type 2 diabetes. These include:
The risk factors for developing heart disease also increase the risk for developing type 2 diabetes.
Untreated high blood pressure can increase the risk for developing type 2 diabetes.
A low level of high-density lipoprotein (HDL) cholesterol and/or a high level of triglycerides can increase the risk for developing type 2 diabetes.
For example, acanthosis nigricans, which is a skin condition.
You can take steps to prevent type 2 diabetes. Even small changes can make a difference, and it's never too late to start making healthier choices.
A healthy weight is one that is right for your body type and height and is based on your body mass index (BMI) and the size of your waist (waist circumference). Losing just 5% of your body weight can help reduce your risk for type 2 diabetes.
Do activities that raise your heart rate. Try to do at least 2½ hours of moderate activity to vigorous activity spread over 5 days.footnote 2 Walking groups or programs are great ways to start exercising and to stay motivated.
Eat a balanced diet, including whole grains, lean sources of protein, and vegetables. Get enough fibre.
Eating fewer calories and exercising more can help you lose weight, if you need to.
Many people have prediabetes before they have type 2 diabetes. If exercise, eating healthy foods, and being at a healthy weight don't help lower your blood sugar, you may need to take medicine. For people who have prediabetes, the medicine metformin can help prevent type 2 diabetes.
Some people who have type 2 diabetes may not have any symptoms early on. You may have the disease for many years before you have symptoms of high blood sugar.
Symptoms of high blood sugar may include:
The higher your blood sugar rises, the more likely you are to have symptoms. High blood sugar can also make you dehydrated if you're not drinking enough liquids. This can make you feel dizzy and weak, and it can lead to an emergency called a hyperosmolar hyperglycemic state.
You're not likely to get symptoms of low blood sugar unless you take insulin or use certain diabetes medicines that lower blood sugar. Common symptoms of low blood sugar include:
You'll keep hearing about how important it is to keep your blood sugar within a target range. That's because over time, high blood sugar can lead to serious problems. It can:
When people hear the word "diabetes," they often think of problems like these. But daily care and treatment can help prevent or delay these problems. The goal is to keep your blood sugar in a target range. That's the best way to reduce your chance of having more problems from diabetes.
Call 911 or other emergency services immediately if:
Less common in type 2 diabetes is diabetic ketoacidosis (DKA), which has symptoms similar to those of hyperosmolar state. But DKA is still possible and very dangerous.
Call a doctor now if:
Check with your doctor if:
If your doctor thinks that you may have diabetes, you will have blood tests to measure how much sugar is in your blood. A fasting blood sugar (glucose) test, an oral glucose tolerance test, and a hemoglobin A1c test are used. Your doctor will also ask you questions about your medical history and do a physical exam for type 2 diabetes.
Your doctor will use the test results and the Diabetes Canada criteria to diagnose type 2 diabetes.
Two tests are used to confirm the diagnosis of diabetes.
It may be hard to tell if you have type 2 or type 1 diabetes. If so, your doctor may do a C-peptide test or test for autoantibodies to help diagnose type 1 diabetes or a slowly developing form of type 1 diabetes called latent autoimmune diabetes in adults (LADA). Some rare forms of diabetes are caused by a genetic problem. You may need genetic testing to diagnose them. This includes maturity onset diabetes of the young (MODY). There are many types of MODY, depending on the gene that is affected.
Tests you may have include:
This shows whether your blood sugar has been staying within your target range.
High blood pressure can damage nerves and blood vessels.
High cholesterol raises the risk for heart attack and stroke.
This checks for protein in the urine, a sign of kidney damage.
This shows how well your kidneys are working.
The doctor checks for foot sores and loss of sensation.
The dentist checks for gum disease and tooth decay.
This checks for damage to the back of the eye (diabetic retinopathy).
This checks for thyroid disease.
Treatment for type 2 diabetes will change over time to meet your needs. But the focus of your treatment will usually be to keep your blood sugar levels in your target range. This will help prevent problems such as eye, kidney, heart, blood vessel, and nerve disease.
Some people may need medicines to help their bodies make insulin or decrease insulin resistance. Some medicines slow down how quickly the body absorbs carbohydrates.
Treatment to manage type 2 diabetes includes:
There is no known cure for type 2 diabetes. But it can be controlled. And in some cases, it goes into remission.
Avoid products that promise a cure for type 2 diabetes. For example, antioxidant supplements (vitamins E, C, and carotene) don't cure diabetes. Diabetes Canada does not recommend taking them.footnote 3
If you hear about something new to help type 2 diabetes, check with your doctor or a diabetes educator to find out if it really works. Your health plan may also provide health information on its website.
Making healthy choices is a big part of managing type 2 diabetes. Here are some important steps you can take.
Follow your meal plan to know how much carbohydrate to eat at each meal and snack. Carbohydrate affects blood sugar more than any other nutrient. It's in breads, cereals, vegetables, fruit, milk, yogurt, and sugary foods like candy and cake.
You can use your blood sugar results to adjust your food and activities to stay in your target range.
One way to do this is to be active 30 minutes a day, at least 5 days a week. Walking is a good choice. You also can try other activities, like running or playing team sports.
Your risk of harm from alcohol is low if you have 2 standard drinks or less per week. Work with your doctor to find what is right for you.
If you need help quitting, talk to your doctor about stop-smoking programs and medicines. These can increase your chances of quitting for good.
You may be overwhelmed by how much you need to learn and change. Talk with your family and friends about your feelings, and ask for help if you need it.
This blood test shows how steady your blood sugar levels have been over time. Your doctor may recommend that you get this test every 3 to 6 months.
Work with your doctor to manage your blood pressure and cholesterol, and talk to your doctor about foot exams and other tests. Tests to do every year may include:
If you take diabetes medicine, take it exactly as prescribed. Do not stop or change your medicine without talking to your doctor first.
Work with your doctor to make a plan for what to do when you are sick. Being sick can affect your blood sugar.
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Some people with type 2 diabetes need medicines to help their bodies make insulin, decrease insulin resistance, or slow down how quickly their bodies absorb carbohydrates.
Medicines that may be prescribed include:
It lets sugar (glucose) in the blood enter cells, where it is used for energy. Without insulin, the blood sugar level gets too high.
Insulin can be taken as a shot (injection) or through an insulin pump. Most people who take it use a combination of short-acting and long-acting insulin. This helps keep blood sugar within the target range.
Your healthcare provider may recommend bariatric surgery (also called weight-loss surgery) to help manage your type 2 diabetes and if your body mass index (BMI) is
CitationsDiabetes Canada Clinical Practice Guidelines Expert Committee, et al. (2018). Screening for diabetes in adults. Canadian Journal of Diabetes, 42(Suppl 1): S16–S19. DOI: 10.1016/j.jcjd.2017.10.004. Accessed October 15, 2018.Diabetes Canada Clinical Practice Guidelines Expert Committee, et al. (2018). Reducing the risk of developing diabetes. Canadian Journal of Diabetes, 42(Suppl 1): S20–S26. DOI: 10.1016/j.jcjd.2017.10.033. Accessed October 12, 2018.Diabetes Canada Clinical Practice Guidelines Expert Committee, et al. (2018). Complementary and alternative medicine for diabetes. Canadian Journal of Diabetes, 42(Suppl 1): S154–S161. DOI: 10.1016/j.jcjd.2017.10.023. Accessed October 15, 2018.Diabetes Canada Clinical Practice Guidelines Expert Committee, et al. (2018). Weight management in diabetes. Canadian Journal of Diabetes, 42(Suppl 1): S124–S129. DOI: 10.1016/j.jcjd.2017.10.015. Accessed October 15, 2018.
Adaptation Date: 6/14/2023
Adapted By: Alberta Health Services
Adaptation Reviewed By: Alberta Health Services
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