According to the American Diabetes Association, nearly 40 million Americans have diabetes. Of that population, just under 30 million were diagnosed, leaving the other 8.5 million undiagnosed. The CDC estimates that about 1 in 4 U.S. adults have undiagnosed diabetes.

Something else that gets in the way of people getting checked for and accurately diagnosed with the disease is diabetes stigma, which, according to the CDC, is "... the false idea that people with diabetes made unhealthy food and lifestyle choices, which resulted in their diagnosis."

If you're undiagnosed how do you know if you might have diabetes or be pre-diabetic?

10 warning signs of diabetes

Here are warning signs to look out for according to Dr. Ajaykumar D. Rao the chief of the section of Endocrinology, Diabetes and Metabolism at the Lewis Katz School of Medicine at Temple University.

1. Urinating and unquenchable thirst

Frequent urination is the most common warning sign of diabetes, Rao said, and comes with extreme thirst. 

“Those two in connection is really going to be concerning or should bring up alarm signs to people to perhaps get tested for diabetes,” Rao said.

Rao said that the body detects high sugar levels and finds ways to have the sugar exit the body in its natural defense process. The easiest way to get rid of the excess sugar is through urination, but excessive urination can also lead to dehydration. 

“It’s not only the sugar that’s being lost, but also the water,” Rao said.

Rao says that sometimes people with diabetes could have issues with uncontrollable urination at night. For men, this might be mistaken for a prostate problem but it is actually “the body trying to get rid of sugar through urination,” he said.

1. Dramatic weight change

There might be dramatic weight gain or loss, Rao said. People who have Type 1, specifically, often present weight loss because of the lack of insulin production from their body. Diabetics can gain weight if they begin receiving insulin treatment, according to the Mayo Clinic. But with lifestyle adjustments, including diet, and even medications, this can be remedied.

1. Blurry vision or vision changes

According to the CDC, blurry vision associated with diabetes is caused when high blood sugar damages blood vessels in the retina. When blood vessels are damaged, they may swell or leak, which causes vision to blur. 

Rao says if you or someone you know is having vision changes that are not attributed to anything else, it is important to go through a thorough examination with an ophthalmologist. 

1. Numbness and tingling

Diabetes also may cause nerve damage that causes a numbness or tingling sensation, Rao said. The CDC reports that half of all people with diabetes have nerve damage, known as neuropathy. Increased blood sugar damages nerves which blocks the brain from sending signals to different parts of your body causing numbness or a tingling feeling.

1. Slow-healing wounds

Healthline.com reports that high blood sugar levels, neuropathy, poor circulation and immune system deficiencies all cause wounds to heal slower in diabetics. Many people with diabetes experience a compromised or weaker immune system that prevents wounds from healing properly or efficiently.

1. Frequent infections

Diabetes complications may show up on the skin as well. According to the ADA, diabetics may experience bacterial infections, fungal infections and itching more than people without diabetes.

Additionally, Rao says that urinary tract infections are common in both men and women. Women may experience more yeast infections as a response to the high blood sugar.

“Getting to the point where the patient is not responding properly to antibiotics and continues to have that again, it could be, again, the high sugars are putting them at risk for infections,” Rao said.

1. Foot problems

Rao said lower extremity foot problems such as calluses or ulcers in their feet is another reason for individuals to seek medical attention and get diagnosed. 

According to the American Diabetes Association, foot problems are often caused by nerve damage. If not cared for, calluses can turn into ulcers, which are then prone to infection. 

1. Fatigue

Fatigue may also be connected to dehydration and unquenchable thirst, Rao said. Although this may be a warning sign of diabetes, it is also a generic side effect for other diseases, medications or lifestyles. Rao highlights that it is important not to self-diagnose and seek the advice of a professional. 

1. Mood changes

Like fatigue, mood changes may be a sign of diabetes but could also be a symptom of other health conditions, too. Sometimes people with preexisting psychological or psychiatric disorders may experience mood changes more than others, Rao said. However, it is not always specific to diabetes.

“If anybody has a new medical disorder that develops on top of a preexisting mental health situation, it might make those things a little but more difficult to manage,” Rao said.

1. Chest pains

Oftentimes, patients who have chest pains or heart attacks will be diagnosed with diabetes. Patients may be undiagnosed, find out they have diabetes and have gone a long time without knowing or regulating their chronic disease, Rao said.

What is diabetes?:From types to causes, what to know about one of the deadliest diseases.

How to know if you have diabetes

If you are experiencing any of these warning signs, it is important to be diagnosed by a medical professional.

“You have to work with your providers,” Rao said. “I think it’s crucial to get engaged with them. It’s crucial to find out if you're diagnosed with diabetes or that you need to be screened.”

By working with your medical care provider, you will be able to manage your symptoms and regulate the effects of diabetes.

“Be persistent to get in and get screened,” Rao said. “It can be as simple as a blood test. There are a lot of ways to get screens, even if you can’t get it through your provider.”

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