Type 1 vs. Type 2 diabetes
A little more than 1 in 10 Americans — or 34.2 million — have diabetes, according to the American Diabetes Association. Of those, 1.6 million have Type 1 diabetes, while the rest have Type 2. With the different types of diabetes and the large portion of the population affected, it’s easy to get confused by diabetes causes. Is Type 1 or Type 2 diabetes the one that can come on with age and obesity? How much of diabetes is due to genetics?
Insulin is the hormone in your body that assists blood sugar to enter cells in your body so it can be used for energy. If there’s no insulin, sugar levels can build up in your bloodstream.
Type 1 diabetes is what you have when your body’s pancreas doesn’t make insulin or only makes a small amount of it. In the past, Type 1 diabetes was previously called juvenile diabetes because it often is diagnosed in children and teens. However, it can develop at any age. Type 1 diabetes is considered an autoimmune disease and isn’t preventable. This means your immune system mistakenly attacks healthy cells in the body.
Type 2 diabetes is more common in adults, although a growing number of children and young adults are getting diagnosed with Type 2 diabetes. With Type 2 diabetes, your cells don’t respond to insulin as they normally should, which is called insulin resistance. This leads to the pancreas making more insulin. Over time, this causes your blood sugar levels to increase.
What causes Type 1 diabetes?
It’s not always clear what causes Type 1 diabetes. However, there are some potential triggers for the development of it, including a family history of Type 1 diabetes and viral infections.
Type 1 diabetes is not associated with dietary or lifestyle patterns, says certified diabetes care and education specialist Carrie Swift, who is a spokesperson for the Association of Diabetes Care and Education Specialists and a quality coordinator at Kadlec Regional Medical Center in Richland, Washington.
There was a 30% increase in Type 1 diabetes diagnoses in the U.S. from 2002 to 2015, according to a report from the Centers for Disease Control and Prevention. Researchers are still exploring causes for this growth in Type 1 diabetes.
Type 2 diabetes causes: genetics and race/ethnicity
Genetics play a role in Type 2 diabetes. If you have a parent with Type 2 diabetes, your risk of developing it increases by 30%, says Erin Palinski-Wade, a Sparta, New Jersey-based registered dietitian and author of “2 Day Diabetes Diet.” If both parents have it, your risk shoots up by 50%.
There is likely a combination of genetics along with your environment that determines if you’ll develop Type 2 diabetes, says Dr. Deena Adimoolam, a Jersey City, New Jersey-based specialist in endocrinology and primary care prevention. Adimoolam is also a member of the U.S. News Medical Review Board.
If you have genes linked to Type 2 diabetes and you’re overweight or obese, you’re more likely to develop it. Exercise and a healthy diet can reduce your diabetes risk, she adds.
The risk for developing diabetes also increases in certain racial and ethnic groups, including:
— American Indians.
— Asian Americans.
— Pacific Islanders.
Type 2 diabetes causes: poor food choices
The foods you eat can make a difference in the development of diabetes. Sugar-filled foods and foods with no nutritional value can raise the risk for diabetes, including:
— Sugary drinks such as soda, energy drinks and sweetened coffee drinks.
Repeated consumption of these types of foods can raise your insulin levels and eventually cause your body’s cells to lose sensitivity to insulin, says Dr. Linda Anegawa, a Honolulu-based physician with virtual primary care and mental health platform PlushCare. This can raise your blood sugar levels and eventually lead to Type 2 diabetes.
Do your best to focus instead on eating more vegetables, whole fruit and fiber, Palinksi-Wade advises.
Type 2 diabetes causes: lack of physical activity
Too little physical activity can also increase your chance of developing diabetes, according to the CDC. That’s because exercise helps to control your blood glucose levels. Plus, physical activity can help you with weight loss. Carrying too much weight can contribute to a higher diabetes risk.
Federal guidelines recommend 150 minutes of moderate physical activity a week, which breaks down to 30 minutes, five times a week. Find physical activity that you enjoy, be it walking, swimming, dancing or aerobics. You can also find ways to sneak in more movement throughout the day, such as doing short, brisk walks after each meal.
Type 2 diabetes causes: age
Age by itself doesn’t cause Type 2 diabetes, but changes that occur as you age can raise your risk of developing it, Palinski-Wade says. Age can increase your risk for diabetes, particularly after age 50, Adimoolam says. This is due to hormonal changes associated with menopause in women and general changes in fat and muscle distribution with age. Those changes can lead to more fat tissue, which adds to insulin resistance.
However, keep in mind that Type 2 diabetes is on the rise among children and young adults, so you’re not safe from diabetes even if you’re under age 50. In fact, a report from the CDC found that Type 2 diabetes among those under age 20 increased 4.8% per year from 2002 to 2012.
Type 2 diabetes causes: being overweight or obese
If you’re overweight or obese, you have a greater chance of developing Type 2 diabetes. That’s because you have high amounts of fat tissue, which can cause insulin resistance and lead to Type 2 diabetes, Adimoolam says.
In particular, excess fat in your belly — also called visceral fat — can shoot up your risk for Type 2 diabetes. One tip to keep in mind: A waist circumference of more than 35 inches for women and 40 inches for men can increase your chance of developing diabetes.
If you’re struggling to lose weight, ask a primary care doctor for help. “Too often, people turn to fad diets or think that it’s all about willpower. This is not the case,” Anegawa says. “Your doctor can help you and even determine if medication can help.”
Other causes of diabetes
Beyond the usual genetic, food and weight-related causes of diabetes, there are other possible causes.
— Latent autoimmune diabetes in adults. Sometimes referred to as Type 1½ diabetes, this is similar to Type 1 diabetes because it’s an autoimmune condition, but is more likely to occur in adults over age 30, Swift says. This often leads to a misdiagnosis of Type 2 diabetes.
— Maturity onset diabetes of the young, a type of diabetes caused by a gene mutation.
— Chronic pancreatitis diabetes. Inflammation in the pancreas can damage this organ, leading to high blood sugars. It could lead to a need for insulin the rest of your life, Swift says.
Less common causes of diabetes
Two additional and less common diabetes causes include:
— Cystic fibrosis-related diabetes. Cystic fibrosis is associated with a thick, sticky mucus, and this can scar the pancreas. Over time, this could stop the pancreas from making adequate amounts of insulin.
— COVID-19. A small percentage of people who have had COVID-19 have developed diabetes. Dr. Francis Collins, director of the National Institutes of Health, supported the connection between COVID-19 and new-onset diabetes in a June 2021 article. A November 2020 study in Diabetes, Obesity and Metabolism found that among those hospitalized for COVID-19, 14.4% went on to develop diabetes. This may be due to the virus replicating and impairing the function of the insulin-producing beta cells in the pancreas, Anegawa says.
It’s also possible that these patients had mild insulin resistance before getting COVID-19, and the infection led to insulin resistance due to the stress placed on the body. If these patients received steroids as part of their treatment, this could have increased insulin resistance and put their blood sugar values in the Type 2 diabetes range, Adimoolam says. Researchers are still exploring the link between diabetes that develops after COVID-19 infection.
What to do if you think you’re at risk for diabetes
To find out if you’re at risk for diabetes, Swift recommends starting with a quick risk test available on the American Diabetes Association website. If your results show you’re at a higher risk for Type 2 diabetes, set an appointment with a primary care provider for further evaluation. This will likely include lab work, which can help show your blood sugar level.
Even if you’re at low risk, maintain healthy habits to keep your Type 2 diabetes risk low. Make sure to:
— Eat healthy.
— Don’t smoke.
— Keep a healthy weight.
— Maintain regular health checkups.
Causes of diabetes:
— Poor food choices.
— Being overweight or obese.
— Lack of physical activity.
— Inflammation in the pancreas.
More from U.S. News
Update 03/07/22: This article was published at an earlier date and has been updated with new information.