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Ways Your Blood Sugar is Making You Sick

Here’s what high blood sugar is doing to your health.
FACT CHECKED BY Emilia Paluszek

High blood sugar is linked to a host of serious health conditions and should never be left untreated. "Uncontrolled glucose levels over time can lead to bad health problems such as heart disease, kidney failure, retinopathy, and even loss of limbs," says Mihail Zilbermint, MD, expert in endocrinology, diabetes, and metabolism, and an assistant professor at Johns Hopkins School of Medicine. "Essentially any organ that needs blood supply is at risk of failure if you have diabetes." Here are five ways your high blood sugar is making you sick, according to doctors. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Diabetic Neuropathy

doctor checking heart with stethoscope

Long-term high blood sugar can cause diabetic neuropathy, nerve damage caused by diabetes. "About 30 percent of patients with frank diabetes for more than a decade have some neuropathy," says Otis Brawley, MD. "It usually presents as numbness, itching or tingling in the legs but can also be pains. It can even present as digestive problems such as difficulty digesting food or diarrhea due to problems with nerves in the bowels. Most diabetic neuropathy is caused by peripheral artery disease, in which the small blood vessels are obstructed or partially obstructed and cannot carry oxygenated blood to areas of the body. These areas have pain or other difficulties due to the lack of oxygen."


Bone and Joint Disorders

Shot of a doctor explaining a medical procedure with a model to a senior patient while sitting in her office

High blood sugar can lead to many bone and joint issues, including osteoporosis. "Individuals with Type 1 diabetes (the loss of insulin produced by the pancreas) or Type 2 diabetes (the body's inability to use insulin and a slow loss of one's ability to make insulin) have an increased risk of bone fractures and osteoporosis," says nurse practitioner Jenny DeJesus. "Associated with decreased bone mass, women with Type 1 diabetes are 12 times more likely to have a fracture than women without diabetes. Although bone mass may or may not be decreased in those with Type 2 diabetes, there is evidence of altered bone quality. The duration of diabetes also plays a role as those living with the condition for more than 5 years tend to be at a higher risk for fractures and poor fracture healing."


Vision Issues

High blood sugar can lead to serious vision issues, and even blindness. "[Diabetic retinopathy] occurs after extended periods of high blood sugar cause the walls of the small blood vessels in the eye to weaken and begin to leak," says Russel Lazarus, B.Optom (Hons) M.Optom. "Once this happens, parts of the eye begin to have difficulty receiving enough blood. In order to compensate for this, the eye begins creating new blood vessels leading to those parts. Unfortunately, the new blood vessels are also weak, and soon begin to leak as well. Over time, this can lead to scarring of the eye, retinal detachment and even total loss of vision. In many cases, a person with diabetic retinopathy will not experience any symptoms until irreparable damage has already been done to their vision."


Weight Loss

weight fluctuates

High blood sugar can lead to weight loss, doctors warn. "When we diagnose someone, we assume they have probably already had diabetes for about five years," says endocrinologist Kevin Pantalone, DO. "Often what happens is people minimize the symptoms or rationalize them and they get worse until they become severe enough that they have to see someone. They have excessive weight loss or are really tired of peeing all night."


Sleep Issues

woman sleeping at night with eye mask

High blood sugar can interfere with sleep and cause insomnia. "This isn't a surprise," says Elena Christofides, MD, FACE. "Stress is a known contributor to the development and progression of obesity and diabetes because it causes the body to not be ever able to go into repair and relaxation mode. It is always in reaction mode… It's not just one night [with insomnia] that's the problem. It's night after night. Quality sleep allows your body to go into rest and repair mode instead of active mode."

Ferozan Mast
Ferozan Mast is a science, health and wellness writer with a passion for making science and research-backed information accessible to a general audience. Read more about Ferozan
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