To explain what hemoglobin A1c is, think in simple terms. Sugar sticks, and when it's around for a long time, it's harder to get it off. In the body, sugar sticks too, particularly to proteins. The red blood cells that circulate in the body live for about three months before they die off. When sugar sticks to these hemoglobin proteins in these cells, it is known as glycosylated hemoglobin or hemoglobin A1c (HBA1c). Measurement of HBA1c gives us an idea of how much sugar is present in the bloodstream for the preceding three months. In most labs, the normal range is 4%-5.9 %. In poorly controlled diabetes, its 8.0% or above, and in well controlled patients it's less than 7.0% (optimal is <6.5%). The benefits of measuring A1c is that is gives a more reasonable and stable view of what's happening over the course of time (three months), and the value does not vary as much as finger stick blood sugar measurements. There is a direct correlation between A1c levels and average blood sugar levels as follows.
^ Jump up to: a b Picot J, Jones J, Colquitt JL, Gospodarevskaya E, Loveman E, Baxter L, Clegg AJ (September 2009). "The clinical effectiveness and cost-effectiveness of bariatric (weight loss) surgery for obesity: a systematic review and economic evaluation". Health Technology Assessment. 13 (41): 1–190, 215–357, iii–iv. doi:10.3310/hta13410. PMID 19726018.
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.
Type I diabetes, sometimes called juvenile diabetes, begins most commonly in childhood or adolescence. In this form of diabetes, the body produces little or no insulin. It is characterized by a sudden onset and occurs more frequently in populations descended from Northern European countries (Finland, Scotland, Scandinavia) than in those from Southern European countries, the Middle East, or Asia. In the United States, approximately three people in 1,000 develop Type I diabetes. This form also is called insulin-dependent diabetes because people who develop this type need to have daily injections of insulin.
Regarding age, data shows that for each decade after 40 years of age regardless of weight there is an increase in incidence of diabetes. The prevalence of diabetes in persons 65 years of age and older is around 25%. Type 2 diabetes is also more common in certain ethnic groups. Compared with a 7% prevalence in non-Hispanic Caucasians, the prevalence in Asian Americans is estimated to be 8.0%, in Hispanics 13%, in blacks around 12.3%, and in certain Native American communities 20% to 50%. Finally, diabetes occurs much more frequently in women with a prior history of diabetes that develops during pregnancy (gestational diabetes).
Finally, modern society should probably shoulder at least some of the blame for the type 2 diabetes epidemic. Access to cheap, calorie-laden foods may even influence type 2 risk beyond simply their effects on body weight; the stuff that is in processed foods, like high-fructose corn syrup, could alter the body's chemistry or gut microbes in a way that affects health. Add to that the fact that most Americans are sedentary, spending their time sitting in cubicles, driving in cars, playing video games, or watching television. The lack of exercise, plus the abundance of unhealthy foods, cultivates a fertile breeding ground for diabetes.
Type 2 diabetes typically starts with insulin resistance. That is, the cells of the body resist insulin’s efforts to escort glucose into the cells. What causes insulin resistance? It appears to be caused by an accumulation of microscopic fat particles within muscle and liver cells.4 This fat comes mainly from the diet—chicken fat, beef fat, cheese fat, fish fat, and even vegetable fat. To try to overcome insulin resistance, the pancreas produces extra insulin. When the pancreas can no longer keep up, blood sugar rises. The combination of insulin resistance and pancreatic cell failure leads to type 2 diabetes.
Type 1 diabetes is always treated with insulin, a life-saving treatment. Patients will need to take insulin several times a day for the rest of their lives. They will usually learn how to self-administer this. Insulin is usually given through injections under the skin, normally two to four times a day. An increasing number of patients with type 1 diabetes are being treated with ‘insulin pumps’, which provide a continuous supply of insulin.
Diabetes mellitus is a metabolic condition in which a person's blood sugar (glucose) levels are too high. Over 29.1 million children and adults in the US have diabetes. Of that, 8.1 million people have diabetes and don't even know it. Type 1 diabetes (insulin-dependent, juvenile) is caused by a problem with insulin production by the pancreas. Type 2 diabetes (non-insulin dependent) is caused by:
 Diabetes Prevention Program Research Group. Long-term effects of lifestyle intervention or metformin on diabetes development and microvascular complications over 15-year follow-up: the Diabetes Prevention Program Outcomes Study. The Lancet Diabetes & Endocrinology. 2015;3(11):866‒875. You can find more information about this study on the Diabetes Prevention Program Outcomes Study website.
With such a surplus of food nowadays, it's easy to overindulge without physical activity, leading to weight gain and, for some people, eventual Type 2 diabetes. "It's a lack of exercise and still eating like you're 20 years old," says Susan M. De Abate, a nurse and certified diabetes educator and team coordinator of the diabetes education program at Sentara Virginia Beach General Hospital.
Jump up ^ Haw, JS; Galaviz, KI; Straus, AN; Kowalski, AJ; Magee, MJ; Weber, MB; Wei, J; Narayan, KMV; Ali, MK (6 November 2017). "Long-term Sustainability of Diabetes Prevention Approaches: A Systematic Review and Meta-analysis of Randomized Clinical Trials". JAMA Internal Medicine. 177 (12): 1808–17. doi:10.1001/jamainternmed.2017.6040. PMID 29114778.
The causes of diabetes mellitus are unclear, however, there seem to be both hereditary (genetic factors passed on in families) and environmental factors involved. Research has shown that some people who develop diabetes have common genetic markers. In Type I diabetes, the immune system, the body's defense system against infection, is believed to be triggered by a virus or another microorganism that destroys cells in the pancreas that produce insulin. In Type II diabetes, age, obesity, and family history of diabetes play a role.
Abnormal cholesterol and triglyceride levels. If you have low levels of high-density lipoprotein (HDL), or "good," cholesterol, your risk of type 2 diabetes is higher. Triglycerides are another type of fat carried in the blood. People with high levels of triglycerides have an increased risk of type 2 diabetes. Your doctor can let you know what your cholesterol and triglyceride levels are.