Diabetes is a chronic disease that occurs because the body is unable to use blood sugar (glucose) properly. The exact cause of this malfunction is unknown, but genetic and environmental factors play a part. Risk factors for diabetes include obesity and high levels of cholesterol. Some specific causes are discussed below.
Lack of insulin production
This is primarily the cause of type 1 diabetes. It occurs when insulin-producing cells are damaged or destroyed and stop producing insulin. Insulin is needed to move blood sugar into cells throughout the body. The resulting insulin deficiency leaves too much sugar in the blood and not enough in the cells for energy.
Insulin resistance
This is specific to type 2 diabetes. It occurs when insulin is produced normally in the pancreas, but the body is still unable move glucose into the cells for fuel. At first, the pancreas will create more insulin to overcome the body’s resistance. Eventually the cells “wear out.” At that point the body slows insulin production, leaving too much glucose in the blood. This is known as prediabetes. A person with prediabetes has a blood sugar level higher than normal but not high enough for a diagnosis of diabetes. Unless tested, the person may not be aware, as there are no clear symptoms. Type 2 diabetes occurs as insulin production continues to decrease and resistance increases.
Symptoms of insulin resistance »
Genetics plays a role in determining how likely you are to develop some type of diabetes. Researchers don’t fully understand the role of genetics in the development of diabetes. According to the American Diabetes Association, statistics show that if you have a parent or sibling with diabetes, your odds of developing it yourself increase.
Although research is not conclusive, some ethnic groups seem to have a higher rate of diabetes. This is true for:
- African-Americans
- Native Americans
- Asians
- Pacific Islanders
- Hispanic Americans
Genetic conditions like cystic fibrosis and hemochromatosis can both damage the pancreas leading to a higher likelihood of developing diabetes.
Monogenic forms of diabetes result from single gene mutations. Monogenic forms of diabetes are rare, accounting for only 1 to 5 percent of all cases of diabetes found in young people.
A small percentage of pregnant women may develop gestational diabetes. It’s thought that hormones developed in the placenta interfere with the body’s insulin response. This leads to insulin resistance and high levels of glucose in the blood.
Women who develop gestational diabetes during pregnancy are at higher risk for developing type 2 diabetes later in life. According to the Centers for Disease Control and Prevention (CDC), women that deliver a baby that weighs more than 9 pounds are also at greater risk.
According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), your risk of developing type 2 diabetes increases as you age. Your risk goes up after age 45 in particular. However, the incidence of type 2 diabetes is increasing dramatically among children, adolescents, and younger adults. Likely factors include reduced exercise, decreased muscle mass, and weight gain as you age. Type 1 diabetes is usually diagnosed by the age of 30.
Excess body fat can cause insulin resistance. Fatty tissue may cause inflammation that can lead to insulin resistance. But many overweight people never develop diabetes, and more research is needed on the link between obesity and diabetes.
Poor nutrition may contribute to type 2 diabetes. A diet high in calories, fat, and cholesterol increases your body’s resistance to insulin.
Diet tips for insulin resistance »
Exercise makes muscle tissue respond better to insulin. This is why regular aerobic exercise and resistance training can lower your diabetes risk. Talk to your doctor about an exercise plan that is safe for you.
Although rare, certain hormonal conditions can also lead to diabetes. The following conditions can sometimes cause insulin resistance:
- Cushing’s syndrome: Cushing’s syndrome causes high levels of cortisol, which is the stress hormone in your blood. This raises blood glucose levels and may cause diabetes.
- Acromegaly: Acromegaly results when the body makes too much growth hormone. This can lead to excessive weight gain and diabetes if left untreated.
- Hyperthyroidism: Hyperthyroidism occurs when the thyroid gland produces too much thyroid hormone. Diabetes is one of the possible complications of this condition.
Healthy eating is your recipe for managing diabetes.
More than 37 million Americans have diabetes (about 1 in 10), and approximately 90-95% of them have type 2 diabetes. Type 2 diabetes most often develops in people over age 45, but more and more children, teens, and young adults are also developing it.
What Causes Type 2 Diabetes?
Insulin is a hormone made by your pancreas that acts like a key to let blood sugar into the cells in your body for use as energy. If you have type 2 diabetes, cells don’t respond normally to insulin; this is called insulin resistance. Your pancreas makes more insulin to try to get cells to respond. Eventually your pancreas can’t keep up, and your blood sugar rises, setting the stage for prediabetes and type 2 diabetes. High blood sugar is damaging to the body and can cause other serious health problems, such as heart disease, vision loss, and kidney disease.
Symptoms and Risk Factors
Type 2 diabetes symptoms often develop over several years and can go on for a long time without being noticed (sometimes there aren’t any noticeable symptoms at all). Because symptoms can be hard to spot, it’s important to know the risk factors and to see your doctor to get your blood sugar tested if you have any of them.
Testing for Type 2 Diabetes
A simple blood test will let you know if you have diabetes. If you’ve gotten your blood sugar tested at a health fair or pharmacy, follow up at a clinic or doctor’s office to make sure the results are accurate.
Managing Diabetes
Unlike many health conditions, diabetes is managed mostly by you, with support from your health care team (including your primary care doctor, foot doctor, dentist, eye doctor, registered dietitian nutritionist, diabetes educator, and pharmacist), family, and other important people in your life. Managing diabetes can be challenging, but everything you do to improve your health is worth it!
You may be able to manage your diabetes with healthy eating and being active, or your doctor may prescribe insulin, other injectable medications, or oral diabetes medicines to help manage your blood sugar and avoid complications. You’ll still need to eat healthy and be active if you take insulin or other medicines. It’s also important to keep your blood pressure and cholesterol close to the targets your doctor sets for you and get necessary screening tests.
You’ll need to check your blood sugar regularly. Ask your doctor how often you should check it and what your target blood sugar levels should be. Keeping your blood sugar levels as close to target as possible will help you prevent or delay diabetes-related complications.
Stress is a part of life, but it can make managing diabetes harder, including managing your blood sugar levels and dealing with daily diabetes care. Regular physical activity, getting enough sleep, and relaxation exercises can help. Talk to your doctor and diabetes educator about these and other ways you can manage stress.
Make regular appointments with your health care team to be sure you’re on track with your treatment plan and to get help with new ideas and strategies if needed.
Whether you were just diagnosed with diabetes or have had it for some time, meeting with a diabetes educator is a great way to get support and guidance, including how to:
- Develop a healthy eating and activity plan
- Test your blood sugar and keep a record of the results
- Recognize the signs of high or low blood sugar and what to do about it
- If needed, give yourself insulin by syringe, pen, or pump
- Monitor your feet, skin, and eyes to catch problems early
- Buy diabetes supplies and store them properly
- Manage stress and deal with daily diabetes care
Ask your doctor about diabetes self-management education and support services and to recommend a diabetes educator, or search the Association of Diabetes Care & Education Specialists’ (ADCES) nationwide directoryexternal icon for a list of programs in your community.
Type 2 Diabetes in Children and Teens
Childhood obesity rates are rising, and so are the rates of type 2 diabetes in youth. More than 75% of children with type 2 diabetes have a close relative who has it, too. But it’s not always because family members are related; it can also be because they share certain habits that can increase their risk. Parents can help prevent or delay type 2 diabetes by developing a plan for the whole family:
- Drinking more water and fewer sugary drinks
- Eating more fruits and vegetables
- Making favorite foods healthier
- Making physical activity more fun
Healthy changes become habits more easily when everyone makes them together. Find out how to take charge family style with these healthy tips.
Get Support
Tap into online diabetes communities for encouragement, insights, and support. The American Diabetes Association’s Community pageexternal icon and ADCES’s Peer Support Resourcesexternal icon are great ways to connect with others who share your experience.