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Type 2 diabetes is a progressive condition in which blood sugar issues show up gradually. First signs begin with slightly elevated blood sugar (glucose) levels—out of normal range but not high enough to be diagnosed with diabetes. This is called insulin resistance and is the first of four stages of type 2 diabetes.
This article will explain what you can expect at each stage and how to manage the condition as it progresses.
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Insulin resistance is the first sign of blood sugar issues, often occurring years before a type 2 diabetes diagnosis. The food you eat becomes sugar (or glucose) in your body as it enters your blood. The pancreas releases insulin to remove the sugar from your blood and enter your cells for your body to use for energy. When your body is resistant to insulin or doesn’t properly respond to insulin, your blood sugar begins to rise.
As a result, your body signals the liver and muscles to store blood sugar. When the liver can't hold anymore, it sends the extra sugar to fat cells, which get stored as body fat.
While this first stage can go unnoticed, many changes in the body can create serious health issues in the future.
Type A insulin resistance is a rare disorder where the body’s tissues don’t respond to insulin. It’s caused by a mutation in a gene that helps cells take in insulin.
You have prediabetes when your blood glucose is outside the normal range but not high enough to be considered diabetes. While reversible through lifestyle changes, such as diet and exercise, prediabetes increases your chances of developing type 2 diabetes, heart disease, and stroke.
Similar to insulin resistance, you may not see any signs of prediabetes until a blood test reveals glucose levels that are higher than they should be. Prediabetes risk increases if you have:
Prevalence of prediabetes increases for African Americans, Native Hawaiians, Alaska Natives, American Natives, Asian Americans, Hispanics/Latinos, Pacific Islanders, and those 45 or older.
With type 2 diabetes, your blood glucose is in a dangerous range. Normal fasting blood sugar is 99 milligrams of sugar per deciliters of blood (mg/dL) or lower. With prediabetes, blood glucose is between 100 to 125 milligrams of sugar per deciliters of blood. Numbers that are 126 milligrams of sugar per deciliters of blood or higher mean you have type 2 diabetes.
Some with type 2 diabetes may not show symptoms; for others, symptoms may be mild. However, symptoms will get progressively worse.
Type 2 diabetes symptoms include:
Even when you are following your diabetes treatment plan, blood sugar may get out of control due to the condition's progressive nature. If you notice signs of your blood sugar slipping out of the normal range, contact your healthcare provider immediately to discuss your treatment plan.
This final stage of diabetes involves vascular (blood vessel) damage. This includes diabetic retinopathy, atherosclerosis, and diabetic nephropathy. These conditions are caused by years of high blood sugar and are responsible for reduced life expectancy, blindness, and end-stage renal disease in those with type 2 diabetes.
Diabetic retinopathy. The blood vessels in the back of your eye become swollen, leaking fluid into your eye. This can cause vision loss, retinal detachment, glaucoma (optic nerve damage), and cataracts (cloudy eye lens).
Atherosclerosis. A build-up of fat and cholesterol, called plaque, collects in the arteries. It eventually hardens, and blood is unable to move freely. The plaque can get so thick that the pathway through the arteries is completely blocked, causing a heart attack or stroke.
Diabetic nephropathy. High blood sugar can also damage your kidneys. When this happens, the kidneys can’t remove waste and fluid from your body effectively, eventually leading to kidney failure. Treatment requires regular dialysis, a procedure that manually removes waste from the blood until you can receive a kidney transplant.
The only way to prevent or slow the progression of type 2 diabetes is to control your blood sugar. If you’re diagnosed with insulin resistance or prediabetes, you can still avoid type 2 diabetes. If you are diagnosed with type 2 diabetes, prevention and management are the same:
Type 2 diabetes is a progressive disease, making it harder to control your blood sugar over time. Work with your healthcare provider to adjust your treatment plan and medications as needed to help prevent serious complications.
While a type 2 diabetes diagnosis may seem like it comes out of nowhere, the changes in your body begin years before a diagnosis. Diabetes occurs in four stages: Insulin resistance, prediabetes, type 2 diabetes, and type 2 diabetes with vascular complications. You are at higher risk for these conditions if you are older than 45, have close biological relatives with diabetes, are physically inactive, or have extra weight.
If insulin resistance or prediabetes is caught early, lifestyle changes, such as eating a healthy diet, adding exercise to your daily activities, and possibly taking diabetes medication, can prevent you from developing type 2 diabetes.
Blood sugar management is key to preventing the most severe complications, such as eye disease, kidney damage, and cardiovascular disease. Some may be able to reverse type 2 diabetes, but for many, it is a lifelong medical condition.
Being diagnosed with any form of diabetes or insulin resistance can come as a shock. Making significant changes to your eating habits and life routine can be intimidating, but with the help of your healthcare provider, you can create a treatment plan that works for you. Keeping your blood sugar within a normal range will decrease your risk of developing dangerous diabetes complications. As always, talk to your healthcare provider about concerns or if you need to change your treatment plan.
End-stage diabetes is a series of complications that can occur in people who have had diabetes for a long time. These complications can include heart disease, kidney problems, and nerve damage. Older adults are more likely to experience end-stage diabetes because increased frailty and age-related cognitive changes can make it more difficult to manage diabetes.
The average life expectancy of someone with type 2 diabetes is around 63 years. But this is highly dependent on how well you control your diabetes. Eating healthy, doing regular physical activity, and following your healthcare provider’s treatment plan will help keep your blood sugar under control.
Yes, prediabetes is reversible. Think of it as a warning signal. Eating healthy, losing extra weight through regular physical activity, and taking prescribed medications can get your blood sugar levels back in a normal range.
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Carisa D. Brewster is a freelance journalist with over 20 years of experience writing for newspapers, magazines, and digital publications. She specializes in science and healthcare content.
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