How does diabetes affect the body?

Intermountain Registered Dietitians on behalf of Intermountain Healthcare

Nutrition & Dietetics

Diabetes is a life-long disease that can't be cured. But it can be managed. It's easier to do this if you understand what's going on in your body. Diabetes is a metabolic disorder. This means it's a disease that affects how your body uses food for energy and growth.

Here's how things work in a person without diabetes:

When you eat, your body breaks food down into glucose. Glucose is a type of sugar that is your body's main source of energy.
Glucose from food goes into your bloodstream. Your blood glucose (the amount of sugar in your blood) begins to rise.
As your blood glucose rises, your pancreas responds by releasing a hormone called insulin.
Insulin allows glucose to cross out of your bloodstream and go into your body's cells -- it's like a key that "unlocks" the cells. Once glucose gets in your cells, it's used for energy.
Your liver also plays a role in the metabolic process. It stores glucose from your bloodstream and releases it when your cells need fuel (as, for example, when you haven't eaten for a while). When you have eaten, however, insulin blocks this release of glucose from your liver.

When you have diabetes, your body still breaks down the food you eat into glucose. The problem is that your body doesn't have the right amount of insulin. The reasons for this depend on the type of diabetes you have, type 1 or type 2. But with both types of diabetes, the end result is the same:

Your cells are starved for energy. Without an insulin "key" to help move glucose into your cells, you feel weak, hungry, and thirsty -- just plain awful. You'll also have ketones in your blood and urine (pee). Ketones are a sign that your body is breaking down fat and protein to get energy, since it's not able to use glucose normally. High levels of ketones are harmful to your body.
Your blood glucose is too high. Unused glucose from the food you eat builds up in your bloodstream. If you don't have enough insulin (as with type 1 diabetes) your liver will release even more glucose as well. If your blood glucose gets high enough, glucose will "spill" into your urine. Over time, high levels of blood glucose can damage your nerves and blood vessels. Therefore, your doctor will do tests over the years to monitor any changes and make sure you get the right care at the right time to stay healthy.

Honor Society of Nursing (STTI)

If left untreated or not treated properly, diabetes mellitus can affect every part of the body. In diabetes mellitus, the body does not process blood sugar properly. Elevated blood sugar levels, especially when sustained over long periods of time, can greatly increase the risk of cardiovascular disease and stroke.This condition may also damage nerves, especially those to your legs, increase the risk of eye problems, complications with the feet, and other problems. It is very important to follow your doctor's treatment program to reduce the risk of these complications related to diabetes. (Diabetes insipidus, a rare disease, may be dangerous, causing severe dehydration, but does not elevate blood sugar and does not affect the body in the same way.)

Dr. Mehmet Oz, MD

Cardiology (Cardiovascular Disease)

Diabetes ages you 1.5 years for every year you live. For example, get it at age 30 and live to 60, you're not really 60, but you have the energy and disability risks of a 75-year-old.

Type II diabetes makes sugar build up in your bloodstream rather than directly into your cells. That causes weakness in the seals between cells in your arteries allowing cholesterol to seep in. It also causes sugar to attach to proteins and make them less effective. That causes a host of health problems. For example:

It increases your blood pressure.

It increases your risk of heart attacks, strokes, memory loss, kidney failure, eye problems, arthritis and lung disease.

It decreases your ability to fight off infections.

American Diabetes Association

Diabetes can damage many parts of the body: the eyes, heart, blood vessels, nervous system, teeth and gums, feet and skin, and kidneys. These are called chronic, or long-lasting, complications. However, studies have shown that keeping blood glucose, blood pressure, and cholesterol close to target levels can help prevent or delay the harmful effects of diabetes.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.