High blood sugar (hyperglycemia) occurs when the body fails to produce enough insulin, leaving extra sugar in the bloodstream. Hyperglycemia is one of the hallmarks of diabetes. High blood sugar can be managed through diet, exercise and medication (insulin); however, if blood glucose is not adequately managed, it can cause potentially serious effects on the body. Untreated, uncontrolled or chronic high blood sugar can lead to complications that affect vital organs, tissues and nerves.
Early Effects
When blood sugars exceed normal levels, the body shows some early signs. Common effects of high blood glucose include increased thirst and hunger, frequent urination, dry skin, blurred vision, weakness, fatigue, numbness or tingling in the feet and weight loss. Noticeable increases in infection and problems healing may develop, as well. Specifically, vaginal and skin infections may arise, and cuts or sores may take longer than normal to heal. Upon urinalysis testing, sugar is also detectable in the urine.
Ketoacidosis
When the body does not have enough insulin to break down blood sugar as it rises, it instead starts to break down fat for energy. This releases toxic acids called ketones into the body, leading to a potentially fatal condition known as ketoacidosis.
Some of the symptoms of ketoacidosis may overlap the early signs of high blood sugar. These include excessive thirst, weakness or fatigue and frequent urination. However, ketoacidosis has additional serious effects on the body including nausea and vomiting, abdominal pain, shortness of breath and loss of appetite. It also gives the breath a fruity scent and can lead to feelings of mental confusion.
Hyperosmolar Syndrome
When blood sugar levels exceed 600 milligrams per deciliter, the blood becomes thick and syrupy, leading to a condition known as Hyperosmolar Syndrome. Excess sugar is filtered out into your urine along with so much fluid that you could develop life-threatening dehydration. Over a period of days or weeks, symptoms such as dry mouth, warm skin, absence of sweating, drowsiness, confusion, vision loss or weakness on one side of the body may emerge.
Chronic Effects
When blood sugar levels stay high over long periods of time, they can cause damage to the body's vital organs and tissues. Hyperglycemia is associated with peripheral nerve damage that may necessitate amputation of the feet or digits of the hands. It also causes blood flow disruptions and blockages in the arteries (known as vascular disease). These blockages can occur anywhere in the body and may have serious effects. For example, blood flow to the eyes may be affected, causing a condition known as retinopathy. Hyperglycemia can also affect the kidneys (nephropathy) and the heart, leading to high blood pressure, high cholesterol and cardiovascular disease. Impeded blood flow to the lungs, brain or limbs may also cause blood clots that can result in stroke.
