In a study of individuals at risk for developing type 2 diabetes, researchers identified genetic variants linked with participants’ responses to two different blood sugar–lowering drugs.
Type 2 Diabetes
When your body can't make enough insulin or can't use insulin, it is called type 2 diabetes. Insulin helps the cells in the body absorb glucose, or sugar, for energy. Without insulin, glucose builds up in the blood resulting in high blood sugar.
Corrigan Minehan Heart Center
The Cardiovascular Disease Prevention Center at the Massachusetts General Hospital Corrigan Minehan Heart Center takes a prevention-as-treatment approach to caring for the heart and overall cardiovascular system.
We provide comprehensive care to children and adolescents with both type 1 (juvenile-onset; insulin-dependent) and type 2 (adult-onset; non-insulin-dependent) diabetes mellitus.
The Division of Pediatric Endocrinology and Diabetes Center at Mass General for Children is an international referral center for the management of pediatric diabetes and endocrine disorders in children and adolescents.
Type 2 Diabetes
What is type 2 diabetes?
Type 2 diabetes is when your body can’t make enough insulin. Or it means your body can't use the insulin well. Insulin helps your cells use sugar (glucose) for energy. Without insulin, glucose builds up in your blood. This leads to high blood sugar.
Type 2 diabetes is an ongoing (chronic) disease. It has no known cure. It's the most common type of diabetes.
What causes type 2 diabetes?
The exact cause of type 2 diabetes is not known. It seems to run in families. But it often takes other things to bring on the disease. These include:
Not getting enough physical activity
Taking certain medicines
Who is at risk for type 2 diabetes?
You are at higher risk for diabetes if you have any of these:
Older age. People ages 35 and older are at higher risk for diabetes.
Family history of diabetes. It tends to run in families.
Extra weight. Being overweight puts you at higher risk.
Lack of exercise. Not enough physical activity puts you at risk.
Taking certain medicines. These include steroids and some water pills (diuretics). They also include medicines for mental health called antipsychotics.
Race and ethnicity. People who have African, Hispanic, Asian, Pacific Island, or American Indian heritage are more likely to develop type 2 diabetes.
Gestational diabetes. Having diabetes in pregnancy puts you at higher risk for type 2 diabetes later.
Prediabetes. This is when you have blood sugar levels higher than normal, but not high enough to be diabetes. Weight loss and medicines can help prevent type 2 diabetes in people who have prediabetes.
Low HDL. This means low levels of the good cholesterol.
A high triglyceride level. This is a type of blood fat.
Smoking. Being a smoker puts you at higher risk.
Other health problems. Polycystic ovary syndrome (PCOS) puts you at higher risk. So do patches of darker skin (acanthosis nigricans), or being born at a low birth weight.
What are the symptoms of type 2 diabetes?
Symptoms may include:
Frequent bladder infections
Skin infections that don't heal easily
Feeling very thirsty
Nausea and vomiting
Feeling very weak and tired
Irritability and mood changes
Dry, itchy skin
Tingling or loss of feeling in the hands or feet
Some people don’t have symptoms. Or symptoms may be mild and you may not notice them. Half of all people in the U.S. who have diabetes don't know it.
How is type 2 diabetes diagnosed?
Diabetes can be diagnosed with several tests. It's best to repeat the tests a second time to confirm the results. The tests include:
Hemoglobin A1C test. The A1C test measures your average blood glucose for the past 2 to 3 months. An A1C of 6.5% or higher means you have diabetes. Some conditions can affect how accurate the A1C test is. These conditions include sickle cell disease, pregnancy, glucose-6-phosphate dehydrogenase deficiency, HIV, hemodialysis, recent blood loss or transfusion, and erythropoietin therapy.
Fasting plasma glucose (FPG). This test checks your blood glucose levels after 8 hours of fasting. You usually get this test before your first meal of the day. This is called your fasting blood glucose level. A result higher than or equal to 126 mg/dL means you have diabetes.
Oral glucose tolerance test (OGTT). For this test, your glucose level is measured before and then after 2 hours after you drink a sugary drink. This shows how well your body processes glucose. A result of 200 mg/dL or higher after 2 hours means you have diabetes.
Random glucose test. This blood test is done at any time of the day. Blood glucose of 200 mg/dL or higher with symptoms of high blood sugar means you have diabetes.
If you don't have any symptoms of high blood sugar, you will need to have 2 abnormal test results from the same sample or in 2 separate test samples to be diagnosed. An example is a fasting plasma glucose greater than 126 and an A1C greater than 6.5% from the same sample.
How is type 2 diabetes treated?
Treatment will depend on your symptoms, age, and general health. It will also depend on how severe the condition is.
Ask your team about a service called diabetes self-management education and support (DSMES). You will learn skills to help you better manage your diabetes and find support when you need it. This service may be given in a group setting or one-on-one with your team.
The goal of treatment is to keep blood sugar levels as close to normal as possible, but not too low. To do this, you will need to control your blood sugar. You will need to check it regularly.
You may be able to control your type 2 diabetes with:
Healthy eating habits
But you may also need to take medicine or insulin.
Treatment may include some or all of these:
Being more active. Get at least 150 minutes a week of exercise or physical activity. Don’t let more than 2 days go by without being active. When sitting for long periods of time, get up for light activity every 30 minutes.
Meal planning. You will need to eat foods that don’t cause your blood sugar to rise too fast. Your healthcare provider will help you get started with a personal nutrition program.
Weight loss. Losing just 5% to 7% of your body weight can help. Losing 10% or more of your weight and keeping it off gives you even greater benefits. Your type 2 diabetes may go into remission. Talk with your healthcare provider about ways to help you lose weight.
Taking medicine. There are different types of medicines to treat type 2 diabetes. Each type works in a different way to lower blood sugar. You may take 1 or more medicines to improve your blood sugar control.
Taking insulin. If oral medicines don’t work well for you, you may need to inject insulin into your body.
Getting blood tests. You will need to have your A1C level checked several times a year. Experts advise testing at least twice a year if your blood sugar level is in the target range and stable. You will need this test more often if your blood sugar level is not stable.
Routine healthcare. Keep all appointments. This is so your healthcare provider can track your diabetes. You will also need to check your feet daily. This is to look for injuries, sores, or infection. These can lead to severe foot problems.
Vaccines. Get a yearly flu shot. And ask your healthcare provider about vaccines to prevent pneumonia, shingles, COVID-19, and hepatitis B.
What are possible complications of type 2 diabetes?
Diabetes that is not treated or controlled well can cause problems. These can include problems with:
This can lead to:
Amputation of feet
For these reasons, it's important to follow a strict treatment plan.
How daily issues affect your health
Many things in your daily life impact your health. This can include transportation, money problems, housing, access to food, and child care. If you can’t get to medical appointments, you may not receive the care you need. When money is tight, it may be hard to pay for medicines. And living far from a grocery store can make it hard to buy healthy food.
If you have concerns in any of these or other areas, talk with your healthcare team. They may know of local resources to assist you. Or they may have a staff person who can help.
Key points about type 2 diabetes
Type 2 diabetes is when your body can’t make enough insulin, or use it well.
Insulin helps the cells in your body use glucose for energy. Without insulin, too much glucose is left in the blood. This causes high blood sugar.
Type 2 diabetes is a chronic disease. It has no known cure. It's the most common type of diabetes.
The exact cause of type 2 diabetes is not known. It tends to run in families.
Diabetes that is not treated or controlled can lead to serious health problems.
The goal of treatment is to keep your blood sugar levels as close to normal as possible, but not too low. You will need to control your blood sugar. You will need to get physical activity, plan meals, and get regular healthcare.
Tips to help you get the most from a visit to your healthcare provider:
Know the reason for your visit and what you want to happen.
Before your visit, write down questions you want answered.
Bring someone with you to help you ask questions and remember what your provider tells you.
At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
Ask if your condition can be treated in other ways.
Know why a test or procedure is recommended and what the results could mean.
Know what to expect if you do not take the medicine or have the test or procedure.
If you have a follow-up appointment, write down the date, time, and purpose for that visit.
Know how you can contact your provider if you have questions.
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