7 Ways High Blood Sugar Affects Your Body—And Why You Should Track It

These type 2 diabetes symptoms—from numb feet to painful blisters and sex problems—can occur when blood sugar is out of control.

Updated on March 29, 2022

Young man and woman in kitchen checking A1C diabetes blood sugar
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Everyone needs a certain amount of sugar in their blood. Carbohydrates from our food and drink are broken down into glucose, a type of sugar that travels into the bloodstream to feed our body’s cells and energize us. Insulin, a hormone produced in the pancreas, is often described as the key that unlocks cells so glucose can get in and be used for energy.

But when you develop insulin resistance, it’s as if the door becomes harder to open. The body responds by producing more insulin, which helps, but only for a while. Eventually, if insulin resistance continues to worsen or the pancreas can’t keep up, blood sugar levels increase, which is characteristic of diabetes.

Treatments to bring blood sugar to healthy levels include lifestyle changes such as healthy eating and exercise. Managing your weight is key, since obesity is thought to be one of the main causes of insulin resistance. Tracking your blood sugar regularly will also help you take control of your levels, and medication or insulin may also be needed. Unless these steps are taken, poor or uncontrolled blood sugar can cause damage to nerves and blood vessels, creating a host of health problems over time.

a Black woman checks her blood sugar levels
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One easy way to manage your blood sugar levels

If you are taking insulin, trying to control your blood glucose, or have been diagnosed with gestational diabetes, one easy way to manage your levels—and reduce your risk of health problems—is to track your blood sugar on a regular basis. There are many over-the-counter test strip kits, meters and lancing devices available that make it easy to test your own blood glucose.

By monitoring your levels, you’ll also have a record of your progress to discuss with your healthcare provider at each appointment. Use Sharecare to record your results, so you don’t have to remember your levels from day to day. You can download Sharecare for your iPhone and for Android.

Here’s how to check your levels using test strips:

  1. Wash your hands.
  2. Insert a test strip in your meter.
  3. Get a sample of blood using your lancing device.
  4. Hold your test strip into the sample of blood and wait.
Man massaging foot pain on blue couch
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Loss of sensation

Nerve damage, especially in the feet and legs, is a complication that may result from diabetes. Symptoms include unsteadiness when you stand or walk, as well as numbness that can limit your ability to feel hot, cold, and pain. Along with the peculiarity of not having any sensation when you walk, being numb means you could suffer a foot injury—such as a blister or cut—and not realize that you’ve been injured. Such injuries could lead to infection. 

While loss of sensation is one side of the coin, the other is that feet may feel tingly, or you may experience shooting pain.

Woman's eye with sty
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Boils and styes

People with type 2 diabetes are more susceptible to bacterial infections, including boils, styes, and infections of the hair follicles and skin around the nails. Skin problems are often an early indicator of type 2 diabetes. If caught early enough, however, these issues can be treated and even prevented.

Senior applying skin cream to hand
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If your skin feels itchy, you may wonder if it’s your clothing or an allergy. But diabetes may be the culprit, as it may cause excessively dry skin. To avoid or control the itchiness, use gentle soap and shampoo, don’t bathe with hot water, and apply cream to soothe your skin. It’s also important to avoid scratching the itch. Scratching can cause skin lacerations, opening them to infection.

Woman wearing socks on bed with cat
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Poor circulation

Type 2 diabetes can lead to a narrowing and hardening of blood vessels in the feet and legs, causing poor blood flow. If your feet are cold, wear socks. Don’t use hot water or a heating pad to warm your feet if they’re numb; you won’t feel the heat and can easily burn them. Poor circulation can also cause your skin to itch in the lower parts of your legs.

insomnia, sleep, unable to sleep, couple in bed, awake
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Sex Problems

Damaged nerves can affect the sex organs and sexual response. Erectile dysfunction may result when the flow of blood to the penis is disrupted and/or the nerves are damaged. High blood pressure, high cholesterol, and obesity, may also contribute to sexual issues. 

Nerve damage may also lead to vaginal dryness, making intercourse painful, and a loss of sensation in the vaginal area, which can interfere with the ability to achieve orgasm.

finger, broken finger nail, fungal infection
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Fungal infections

People with type 2 diabetes are especially susceptible to fungal infections caused by Candida albicans, a common type of yeast infection. Symptoms typically include red rashes that occur in moist skin folds, which are often surrounded by blisters and scales. The armpits, groin, between fingers and toes, and corners of the mouth are common breeding grounds for this infection.

Older man in purple shirt with stomach pain
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The vagus nerve is responsible for moving food through the digestive tract. When the nerve is damaged or not working, the digestive process slows or stops—a disorder called gastroparesis. When food is essentially delayed in the stomach, blood sugar levels become erratic, making it more difficult to manage. Among other digestive problems, food can harden, making it difficult to pass into the small intestine.

Slideshow sources open slideshow sources

National Institute of Diabetes and Digestive and Kidney Diseases. Insulin Resistance & Prediabetes. Last Reviewed May 2018.
American Diabetes Association. Life doesn’t end with type 2 diabetes, Skin Complications, Peripheral Neuropathy, Foot Complications, Complications.
Joslin Diabetes. Diabetes Learning Center.
Mayo Clinic. Diabetic Neuropathy. March 3, 2020.
Centers for Disease Control and Prevention. Candidiasis. Page last reviewed: October 30, 2020.
J Casqueiro, J Casqueiro, & C Alves. Infections in patients with diabetes mellitus: A review of pathogenesis. Indian journal of endocrinology and metabolism. 16 Suppl 1(Suppl1), S27–S36. 2012.

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