Insulin is released into the blood by beta cells (β-cells), found in the islets of Langerhans in the pancreas, in response to rising levels of blood glucose, typically after eating. Insulin is used by about two-thirds of the body's cells to absorb glucose from the blood for use as fuel, for conversion to other needed molecules, or for storage. Lower glucose levels result in decreased insulin release from the beta cells and in the breakdown of glycogen to glucose. This process is mainly controlled by the hormone glucagon, which acts in the opposite manner to insulin.[60]
"Secondary" diabetes refers to elevated blood sugar levels from another medical condition. Secondary diabetes may develop when the pancreatic tissue responsible for the production of insulin is destroyed by disease, such as chronic pancreatitis (inflammation of the pancreas by toxins like excessive alcohol), trauma, or surgical removal of the pancreas.
Pregnancy. Gestational diabetes is a kind of diabetes that happens only during pregnancy. Although gestational diabetes goes away after pregnancy, about half of women who had gestational diabetes are diagnosed with type 2 diabetes within 15 years. Even if they don’t have gestational diabetes, women who give birth to babies who weigh 9 pounds or more are more likely to develop type 2 diabetes later in life. The American Academy of Family Physicians (AAFP) recommends screening for gestational diabetes in pregnant women after the 24th week of pregnancy. The AAFP believes there is not enough evidence to determine the benefit and harm of screening for gestational diabetes in pregnant women before the 24th week of pregnancy.
Hypoglycemia means abnormally low blood sugar (glucose). In patients with diabetes, the most common cause of low blood sugar is excessive use of insulin or other glucose-lowering medications, to lower the blood sugar level in diabetic patients in the presence of a delayed or absent meal. When low blood sugar levels occur because of too much insulin, it is called an insulin reaction. Sometimes, low blood sugar can be the result of an insufficient caloric intake or sudden excessive physical exertion.

Gestational diabetes, a common complication of pregnancy. Gestational diabetes can lead to perinatal complications in mother and child and substantially increases the likelihood of cesarean section. Gestational diabetes is also a risk factor for the mother and, later in life, the child's subsequent development of type 2 diabetes after the affected pregnancy.
^ Boussageon R, Supper I, Bejan-Angoulvant T, Kellou N, Cucherat M, Boissel JP, Kassai B, Moreau A, Gueyffier F, Cornu C (2012). Groop L, ed. "Reappraisal of metformin efficacy in the treatment of type 2 diabetes: a meta-analysis of randomised controlled trials". PLoS Medicine. 9 (4): e1001204. doi:10.1371/journal.pmed.1001204. PMC 3323508. PMID 22509138.
You can live a normal life with well-controlled diabetes. However, you have to pay attention to your diet, weight, exercise, and medicine. If you don’t control your diabetes, you will have too much glucose in your blood. This can lead to serious health problems, including heart disease and damage to the nerves and kidneys. These are known as diabetic complications. Complications include:
When Dan Hamilton was diagnosed with T1D in 1972, the doctor told him he wouldn’t live past 50. Fast forward 45 years, and Dan is strong and healthy at 59. He credits his health to the advancements in treatment and care over the years. He has been an early adopter of every technology that has come along, and exercises regularly as part of a healthy lifestyle.
Other technology devices, like physical activity trackers, are being integrated with some continuous glucose monitor (CGM) systems to help demonstrate how activity impacts blood glucose levels. In the fall of 2017, Fitbit partnered with Dexcom to bring CGM data to Fitbit Ionic. Some health-care programs, like UHC Medicare Advantage plans, are even providing piloting programs in which participants who use CGM technology, like Dexcom, are receiving Fitbit activity trackers.

Type 2 diabetes is a disorder characterized by abnormally high blood sugar levels. In this form of diabetes, the body stops using and making insulin properly. Insulin is a hormone produced in the pancreas that helps regulate blood sugar levels. Specifically, insulin controls how much glucose (a type of sugar) is passed from the blood into cells, where it is used as an energy source. When blood sugar levels are high (such as after a meal), the pancreas releases insulin to move the excess glucose into cells, which reduces the amount of glucose in the blood.

When Dan Hamilton was diagnosed with T1D in 1972, the doctor told him he wouldn’t live past 50. Fast forward 45 years, and Dan is strong and healthy at 59. He credits his health to the advancements in treatment and care over the years. He has been an early adopter of every technology that has come along, and exercises regularly as part of a healthy lifestyle.
Other potentially important mechanisms associated with type 2 diabetes and insulin resistance include: increased breakdown of lipids within fat cells, resistance to and lack of incretin, high glucagon levels in the blood, increased retention of salt and water by the kidneys, and inappropriate regulation of metabolism by the central nervous system.[10] However, not all people with insulin resistance develop diabetes, since an impairment of insulin secretion by pancreatic beta cells is also required.[13]
Findings from the Diabetes Control and Complications Trial (DCCT) and the United Kingdom Prospective Diabetes Study (UKPDS) have clearly shown that aggressive and intensive control of elevated levels of blood sugar in patients with type 1 and type 2 diabetes decreases the complications of nephropathy, neuropathy, retinopathy, and may reduce the occurrence and severity of large blood vessel diseases. Aggressive control with intensive therapy means achieving fasting glucose levels between 70-120 mg/dl; glucose levels of less than 160 mg/dl after meals; and a near normal hemoglobin A1c levels (see below).
A proper diet and exercise are the foundations of diabetic care,[23] with a greater amount of exercise yielding better results.[82] Exercise improves blood sugar control, decreases body fat content and decreases blood lipid levels, and these effects are evident even without weight loss.[83] Aerobic exercise leads to a decrease in HbA1c and improved insulin sensitivity.[84] Resistance training is also useful and the combination of both types of exercise may be most effective.[84]

Your doctor will test your blood sugar every 3 months with an A1C test. Also, you can test your blood sugar on your own throughout the day. You will need to use a blood glucose monitor to check it on your own. This involves pricking your finger for blood and putting a test strip in the blood to get the results. If your blood sugar gets too low, you might feel tired, experience problems with muscle coordination, sweat, have difficulty thinking or speaking clearly, twitch, feel like you’re going to faint, become pale, lose consciousness, or have a seizure. At the earliest sign of any of these symptoms, eat or drink something that will raise your blood sugar fast. This could include candy, juice, milk, or raisins. If you don’t feel better in 15 minutes or if monitoring shows that your blood sugar level is still too low, eat or drink another item to raise your blood sugar fast. Always keep a supply of these items on hand for emergencies.


The World Health Organization recommends testing those groups at high risk[55] and in 2014 the USPSTF is considering a similar recommendation.[59] High-risk groups in the United States include: those over 45 years old; those with a first degree relative with diabetes; some ethnic groups, including Hispanics, African-Americans, and Native-Americans; a history of gestational diabetes; polycystic ovary syndrome; excess weight; and conditions associated with metabolic syndrome.[23] The American Diabetes Association recommends screening those who have a BMI over 25 (in people of Asian descent screening is recommended for a BMI over 23).[60]
With type 2 diabetes, your body doesn’t use insulin well and can’t keep blood sugar at normal levels. About 90% of people with diabetes have type 2. It develops over many years and is usually diagnosed in adults (but more and more in children, teens, and young adults). You may not notice any symptoms, so it’s important to get your blood sugar tested if you’re at risk. Type 2 diabetes can be prevented or delayed with healthy lifestyle changes, such as losing weight, eating healthy food, and being active.
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