While poor vision is hardly uncommon—more than 60 percent of the American population wears glasses or contacts, after all—sudden changes in your vision, especially blurriness, need to be addressed by your doctor. Blurry vision is often a symptom of diabetes, as high blood sugar levels can cause swelling in the lenses of your eye, distorting your sight in the process. Fortunately, for many people, the effect is temporary and goes away when their blood sugar is being managed.
One particular type of sugar that has attracted a lot of negative attention is high-fructose corn syrup (HFCS) — and for good reason, as multiple studies suggest HFCS can influence diabetes risk. Some research in people who are overweight and obese, for example, suggests regularly consuming drinks sweetened with either fructose, a byproduct of HFCS, or glucose can lead to weight gain, and drinks with fructose in particular may reduce insulin sensitivity and spike blood sugar levels.
There are many complications of diabetes. Knowing and understanding the signs of these complications is important. If caught early, some of these complications can be treated and prevented from getting worse. The best way to prevent complications of diabetes is to keep your blood sugars in good control. High glucose levels produce changes in the blood vessels themselves, as well as in blood cells (primarily erythrocytes) that impair blood flow to various organs.
Diabetes mellitus (“diabetes”) and hypertension, which commonly coexist, are global public health issues contributing to an enormous burden of cardiovascular disease, chronic kidney disease, and premature mortality and disability. The presence of both conditions has an amplifying effect on risk for microvascular and macrovascular complications.1 The prevalence of diabetes is rising worldwide (Fig. 37.1). Both diabetes and hypertension disproportionately affect people in middle and low-income countries, and an estimated 70% of all cases of diabetes are found in these countries.2,3 In the United States alone, the total costs of care for diabetes and hypertension in the years 2012 and 2011 were 245 and 46 billion dollars, respectively.4,5 Therefore, there is a great potential for meaningful health and economic gains attached to prevention, detection, and intervention for diabetes and hypertension.
It isn't always easy to start an exercise regimen, but once you get into a groove, you may be surprised at how much you enjoy it. Find a way to fit activity into your daily routine. Even a few minutes a day goes a long way. The American Diabetes Association recommends that adults with diabetes should perform at least 150 minutes of moderate-intensity aerobic physical activity per week (spread over at least three days with no more than two consecutive days without exercise). You don't have to start with this right away, though. Start with five to 10 minutes per day and go from there. To stay motivated, find a buddy, get a fitness tracker, or use another measurement tool that can help you see your progress.

Damage to small blood vessels can affect the eyes, kidneys, and nerves. Damage to eyes, specifically the retina, is called diabetic retinopathy and is the leading cause of blindness. Damage to the kidneys, called diabetic nephropathy, can lead to kidney failure and the need for dialysis. Damage to the nerves that supply the legs and arms and gastrointestinal tract is called diabetic neuropathy. Some people with diabetes who develop peripheral neuropathy (damage to the nerves in the legs) and have poor blood flow to the legs may eventually need an amputation.
Supporting evidence for Shulman's theory comes from observations about a rare genetic illness called lipodystrophy. People with lipodystrophy can't make fat tissue, which is where fat should properly be stored. These thin people also develop severe insulin resistance and type 2 diabetes. "They have fat stored in places it doesn't belong," like the liver and muscles, says Shulman. "When we treat them . . . we melt the fat away, reversing insulin resistance and type 2 diabetes." Shulman's theory also suggests why some people who carry extra fat don't get type 2. "There are some individuals who store fat [under the skin] who have relatively normal insulin sensitivity, a so-called fit fat individual," he says. Because of the way their bodies store fat, he believes, they don't get diabetes.
Diabetes mellitus is a group of metabolic diseases characterized by high blood sugar (glucose) levels that result from defects in insulin secretion, or its action, or both. Diabetes mellitus, commonly referred to as diabetes (as it will be in this article) was first identified as a disease associated with "sweet urine," and excessive muscle loss in the ancient world. Elevated levels of blood glucose (hyperglycemia) lead to spillage of glucose into the urine, hence the term sweet urine.

The amount of glucose in the bloodstream is tightly regulated by insulin and other hormones. Insulin is always being released in small amounts by the pancreas. When the amount of glucose in the blood rises to a certain level, the pancreas will release more insulin to push more glucose into the cells. This causes the glucose levels in the blood (blood glucose levels) to drop.

The information contained in this monograph is for educational purposes only. This information is not a substitute for professional medical advice, diagnosis, or treatment. If you have or suspect you may have a health concern, consult your professional health care provider. Reliance on any information provided in this monograph is solely at your own risk.


People with diabetes aim for a hemoglobin A1C level of less than 7%. Achieving this level is difficult, but the lower the hemoglobin A1C level, the less likely people are to have complications. Doctors may recommend a slightly higher or lower target for certain people depending on their particular health situation. However, levels above 9% show poor control, and levels above 12% show very poor control. Most doctors who specialize in diabetes care recommend that hemoglobin A1C be measured every 3 to 6 months.
If you’re getting a good night’s rest but still find yourself so tired you can barely function, it’s definitely worth mentioning to your doctor. Diabetes often wreaks havoc on a person’s normal blood sugar levels, causing fatigue in the process. In later stages, the tissue death associated with untreated diabetes can also limit circulation, meaning oxygenated blood isn’t being effectively transported to your vital organs, making your body work harder and tiring you out along the way.

^ Jump up to: a b Petzold A, Solimena M, Knoch KP (October 2015). "Mechanisms of Beta Cell Dysfunction Associated With Viral Infection". Current Diabetes Reports (Review). 15 (10): 73. doi:10.1007/s11892-015-0654-x. PMC 4539350. PMID 26280364. So far, none of the hypotheses accounting for virus-induced beta cell autoimmunity has been supported by stringent evidence in humans, and the involvement of several mechanisms rather than just one is also plausible.


Oral Agents. Oral antidiabetic drugs (see hypoglycemic agents) are sometimes prescribed for patients with type 2 diabetes who cannot control their blood glucose with diet and exercise. These are not oral forms of insulin; they are sulfonylureas, chemically related to the sulfonamide antibiotics. Patients receiving them should be taught that the drug they are taking does not eliminate the need for a diet and exercise program. Only the prescribed dosage should be taken; it should never be increased to make up for dietary indiscretions or discontinued unless authorized by the physician.
Treatment of high blood pressure and high cholesterol levels, which can contribute to circulation problems, can help prevent some of the complications of diabetes as well. A low dose of aspirin taken daily is recommended in people with risk factors for heart disease. All people with diabetes who are between 40 and 75 years are given a statin (a drug to decrease cholesterol levels) regardless of cholesterol levels. Younger people with an elevated risk of heart disease should also take a statin .
Scientists have done studies of twins to help estimate how important genes are in determining one's risk of developing diabetes. Identical twins have identical genes and thus the same genetic risk for a disease. Research has found that if one identical twin has type 1 diabetes, the chance that the other twin will get the disease is roughly 40 or 50 percent. For type 2 diabetes, that risk goes up to about 80 or 90 percent. This might suggest that genes play a bigger role in type 2 than in type 1, but that isn't necessarily so. Type 2 is far more common in the general population than type 1, which means that regardless of genetics both twins are more likely to develop type 2 diabetes.
Fasting glucose test This test involves giving a blood sample after you have fasted for eight hours. (18) If you have a fasting blood sugar level of less than 100 milligrams per deciliter (mg/dl), your blood sugar levels are normal. But if you have one from 100 to 125 mg/dl, you have prediabetes, and if you have 126 mg/dl on two separate occasions, you have diabetes. (17)
There are many complications of diabetes. Knowing and understanding the signs of these complications is important. If caught early, some of these complications can be treated and prevented from getting worse. The best way to prevent complications of diabetes is to keep your blood sugars in good control. High glucose levels produce changes in the blood vessels themselves, as well as in blood cells (primarily erythrocytes) that impair blood flow to various organs.
People with type 2 diabetes have insulin resistance, which means the body cannot use insulin properly to help glucose get into the cells. In people with type 2 diabetes, insulin doesn’t work well in muscle, fat, and other tissues, so your pancreas (the organ that makes insulin) starts to put out a lot more of it to try and compensate. "This results in high insulin levels in the body,” says Fernando Ovalle, MD, director of the multidisciplinary diabetes clinic at the University of Alabama in Birmingham. This insulin level sends signals to the brain that your body is hungry.
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