Conditions That Mimic Type 2 Diabetes

"Diabetes mellitus" is an umbrella term that refers to a group of insulin-related metabolic disorders (e.g., type 1 diabetes or type 2 diabetes) that affects the body's ability to turn food into a usable energy source. Insulin is a hormone produced by the pancreas that controls the amount of energy-providing glucose (sugar) in the bloodstream.

Diabetes may be misdiagnosed or missed due to several conditions with one or more of the same symptoms. Getting an accurate diagnosis can be thrown off by conditions that mimic diabetes.

This article explains how to get an accurate type 2 diabetes diagnosis and highlights some conditions that mimic this disease, such as fatigue, numbness or tingling in the hands and feet, mood changes, and frequent urination.

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Fatigue

People with untreated or misdiagnosed diabetes often experience extreme tiredness and fatigue because their body doesn't produce or can't use insulin to manage their blood sugar levels. However, fatigue can be caused by other factors and people without diabetes can have blood sugar issues as well.

Blood sugar levels that are too low (hypoglycemia) or too high (hyperglycemia) can make people feel lethargic and fatigued. The best way to find out if your symptoms of fatigue are linked to blood sugar levels that are too high or too low because of diabetes (or not because of diabetes) is to get lab tests from a healthcare provider.

In nondiabetic individuals with fatigue, blood glucose levels are typically between 70 and 99 milligrams per deciliter (mg/dL). Having blood glucose levels below 70 mg/dL is considered hypoglycemia for people with diabetes. For those without diabetes, blood sugar below 70 mg/dL is also a tipping point between healthy glucose levels and hypoglycemia.

At the other extreme, blood glucose levels higher than 130 mg/dL when fasting or higher than 180 mg/dL a few hours after a meal are typically considered hyperglycemia. In general, blood sugar levels higher than 200 mg/dL indicate hyperglycemia.

If you're feeling tired for no known reason or experiencing a lack of energy that's disrupting your quality of life and isn't resolved by getting more rest, speak to a healthcare provider about your symptoms and the possibility of getting tested to diagnose type 2 diabetes.

Numbness in the Hands or Feet

Nondiabetic neuropathy can cause numbness in the hands and feet that mimics the symptoms of neuropathy caused by diabetes. Neuropathies typically start with a feeling of numbness or tingling in the hands and feet, but other body areas can experience it, too. Although diabetes is the leading cause of neuropathy in the United States, other common causes include:

Mood Changes

People with diabetes may experience mood swings linked to rapid changes in blood sugar levels. However, people can experience mood changes for other reasons. Common causes of mood swings include:

Glucose monitoring is the best way to identify if diabetes is causing these mood changes.

Frequent Urination

Frequent urination or the feeling that you need to urinate more often than usual can be caused by many things. Although frequent urination and the need to get up in the middle of the night to urinate (nocturia) are a symptom of diabetes, other factors can increase urination frequency.

Some common nondiabetic causes of frequent urination symptoms include:

How to Get an Accurate Diagnosis

Blood sugar tests that measure the amount of glucose in the blood are the gold standard for getting an accurate diabetes diagnosis. The A1C test—also known as an HbA1c, glycated hemoglobin, or glycosylated hemoglobin test—is the most commonly used diabetes test.

Other tests used to get an accurate diagnosis for prediabetes, type 1 diabetes, type 2 diabetes, or gestational diabetes include:

Type 2 Diabetes vs. Other Types of Diabetes

Contrary to popular belief, children can develop type 2 diabetes, and type 1 diabetes can appear for the first time when someone is older. Age-related assumptions about different types of diabetes mellitus increase the risk of misdiagnosis. 

Summary

Type 2 diabetes has a number of symptoms that may be mistaken for other disorders. A wide range of diseases and nondiabetic factors can cause symptoms that mimic type 2 diabetes. Blood sugar tests like the A1C, fasting plasma glucose test, or an oral glucose tolerance test are the best way to determine if symptoms of fatigue, numbness in the hands or feet, and frequent urination are being caused by diabetes.

A Word From Verywell

Getting an accurate type 2 diabetes diagnosis can be tricky. Because there are so many conditions that mimic type 2 diabetes, it's important to speak with a healthcare provider and discuss what lab tests can be performed to determine if diabetes is, in fact, causing your symptoms.

Frequently Asked Questions

  • How common is type 2 diabetes misdiagnosis?

    A type 2 diabetes misdiagnosis is relatively common, especially in older adults. As well, many people over age 30 with type 1 diabetes are misdiagnosed with type 2 diabetes, which used to be called adult-onset diabetes. For example, a study of adults over age 30 who'd been diagnosed with type 2 diabetes found that 21% actually had type 1 diabetes.

  • Can type 2 diabetes turn into type 1?

    Type 2 diabetes can't turn into type 1 diabetes. However, many people who originally get a type 2 diabetes diagnosis may discover that they actually have type 1 diabetes and need insulin medications to control their blood sugar. Although type 1 diabetes (formerly known as juvenile diabetes) tends to appear in childhood or adolescence, adults can develop type 1 diabetes and children can develop type 2 diabetes.

  • Can thyroid diseases be mistaken for diabetes?

    Thyroid disease symptoms are often mistaken for diabetes, but the two are closely linked. Accumulating evidence suggests that that there's an increased prevalence of thyroid disorders in patients with diabetes mellitus. People with type 2 diabetes are also more likely to have subclinical hypothyroidism (underactive thyroid gland).

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Christopher Bergland
Christopher Bergland is a retired ultra-endurance athlete turned medical writer and science reporter.