Type 1 diabetes definition and facts
- Type 1 diabetes mellitus (formerly known as insulin-dependent diabetes or juvenile diabetes) is a condition in which the body stops making insulin. This causes the person's blood glucose level (blood sugar) to increase.
- There are two types of diabetes, type 1 and type 2.
- In type 1 diabetes, the immune system attacks the pancreas, which causes the pancreas to stop producing insulin.
- In type 2 diabetes, the pancreas can produce insulin, but the body cannot use it.
- The cause of type 1 diabetes is autoimmune destruction of the pancreatic beta cells, which can be caused by viruses and infections as well as other unknown factors. In many cases, the cause is not known. Scientists are looking for cures for type 1 diabetes such as replacing the pancreas or some of its cells.
- Risk factors for type 1 diabetes are family history, introducing certain foods too soon (fruit) or too late (oats/rice) to babies, and exposure to toxins.
- Diabetic ketoacidosis, also referred to as simply ketoacidosis or DKA, is a serious and even life-threatening complication of type 1 diabetes
- Symptoms of type 1 diabetes are
- Sometimes, there are no significant symptoms.
- Type 1 diabetes is diagnosed by blood tests. The level of blood sugar is measured, and then levels of insulin and antibodies can be measured to confirm type 1 vs. type 2 diabetes.
- Type 1 diabetes is treated with insulin and lifestyle changes. Specifically, meal planning to be sure that carbohydrate intake matches insulin dosing.
- Complications of type 1 diabetes are kidney disease, eye problems, heart disease, and nerve problems (diabetic neuropathy) such as loss of feeling in the feet. Poor wound healing can also be a complication of type 1 diabetes.
- Type 1 diabetes cannot be prevented, however, keeping blood sugar at healthy levels may delay or prevent symptoms or long-term complications. There is currently no cure for type 1 diabetes.
- The prognosis or life expectancy for a person with type 1 diabetes is good if blood sugar levels are kept within a healthy range. The life expectancy for someone with type 1 diabetes traditionally has been about 11 years less than average, but that is changing as the prevention of complications improves and technology such as insulin pumps makes it easier for people to keep their blood sugar in a healthy range.
What is type 1 diabetes?
Type 1 diabetes is an autoimmune disease that affects blood sugar regulation. A person's immune system makes antibodies that destroy the insulin-producing islet beta cells in the pancreas. The pancreas then fails to make insulin. Without insulin, blood sugar increases and cannot be delivered to the muscles and brain where it is needed. Over time, high blood sugar can lead to a number of complications such as kidney, nerve, and eye damage, and cardiovascular disease. Moreover, cells do not receive the glucose necessary for energy and normal function.
Because type 1 diabetes is an autoimmune disease, cures will likely involve replacing the damaged pancreas or promoting regeneration or functioning of the pancreas. Because people with type 1 diabetes can no longer produce their own insulin, they must inject doses of insulin. They must match the amount of insulin they inject with their diet. Keeping blood sugar in a normal, healthy range (what doctors call "good glycemic control") is the key to preventing long-term complications.
Diabetes is defined best as...
Type 1 Diabetes Diet
Foods to Eat and Foods to Avoid
Glycemic index and glycemic load are scientific terms used to measure he impact of a food on blood sugar. Foods with low glycemic load (index) raise blood sugar modestly, and thus are better choices for people with diabetes.
Foods to eat for a type 1 diabetic diet include complex carbohydrates such as
- brown rice,
- whole wheat,
- beans, and
What are the signs and symptoms of type 1 diabetes?
Type 1 diabetes can be subtle or life threatening. Some people have no symptoms (asymptomatic), and type 1 diabetes is not detected until blood or urine lab studies are done. If a person does have type 1 diabetes symptoms, early signs and symptoms are
- weight loss,
- thirst, and
- excessive urination.
Other signs and symptoms are
- an unusual odor to the urine,
- urinary tract infections (UTIs),
- yeast infections,
- unexplained weight loss,
- feeling hungry even after meals,
- stomach pain,
- swollen ankles,
- darkening skin around the armpits or groin,
- night sweats,
- blurry vision,
- fruity or unusual breath,
- hair loss, and
- generally feeling unwell (malaise).
People with type 1 diabetes may experience more frequent infections of the skin or respiratory tract.
Undiagnosed type 1 diabetes can become life threatening if a person goes into ketoacidosis (a state in which elevated blood sugar leads to other metabolic changes).
What is the difference between type 1 and type 2 diabetes?
The major process that happens in type 1 diabetes is that the pancreas can no longer produce insulin. Type 2 diabetes is more a result of insulin resistance (cells not being able to use insulin effectively or at all), that is, it takes a large amount of insulin to move glucose out of the blood and into the cells. Over time, people with type 2 diabetes also may experience decreased insulin production in the pancreas. In type 1 diabetes, over time, the body can also develop insulin resistance -- especially in people who gain a lot of weight while using insulin. This means there is some overlap in treatment and diet for people who have had diabetes of either type for a long time.
How many people have type 1 diabetes?
Most people with diabetes (90%-95% of all those with the condition) have type 2 diabetes. Around 1.25 million American children and adults have type 1 diabetes.
Is type 1 diabetes a genetic (inherited) disease?
There is a strong genetic link with type 1 diabetes. This can be tested for by looking at the human leukocyte antigen (HLA) genotype. First-degree relatives are at higher risk. However, with any genetic condition, it is important to remember that gene expression changes in response to the epigenetic (nutritional) environment, and risk factors can be addressed with a health care professional or nutrition/functional/naturopathic practitioner knowledgeable about epigenetics.
Type 1 Diabetes: What Are The Symptoms?
How do you develop type 1 diabetes (causes)?
Type 1 diabetes is caused by the autoimmune destruction of the pancreatic beta cells that produce insulin. It is not known why the autoimmune destruction happens. However, there are some known triggers, for example:
- Genetics, including family history and the prenatal environment of the mother, can put people at risk for developing type 1 diabetes.
- Exposures to chemicals, especially ones called endocrine disruptors, found in plastics
- Viral infections also can trigger the autoimmune process.
- Early or late introduction of certain foods to infants has been shown to trigger type 1 diabetes in research studies. Introducing fruit before 5 months of age or waiting until later than 7 months to introduce grains such as oats and rice increases the risk of diabetes. However, research shows that breastfeeding reduces these risks.
The underlying cause of type 1 diabetes usually is not known.
What are risk factors for developing type 1 diabetes?
Risk factors for developing type 1 diabetes include prenatal exposures, exposures to food and environmental toxins early in life, and geography.
- Prenatal exposures include maternal preeclampsia or metabolic syndrome .
- Environmental exposures include chemicals, especially those found in plastics and foods, specifically introduction of gluten, casein (the protein in dairy) or fruit before 4 months of age or late introduction (after 7 months of age) to grains (gluten, oat, and rice) and casein.
- Viral infections, such as Epstein-Barr virus or EBV (mononucleosis), Coxsackie, CMV, and other infections can also be risk factors for developing type 1 diabetes.
- Living in a northern climate is a risk factor that has not been fully explained.
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Type 1 diabetes and pregnancy
Pregnant women with type 1 diabetes need to be extra careful to maintain good blood sugar control. If blood sugar runs too high during pregnancy, there is an increased risk of complications including having a very large baby, having the baby too early, and having preeclampsia, a condition that can be life threatening to the mother and baby. You can minimize the risk for complications by paying close attention to blood sugar, eating a low-glycemic diet, and staying regularly active.
How is type 1 diabetes diagnosed?
- Type 1 diabetes is diagnosed with a blood test for blood glucose.
- If it is greater than 125 when fasting or greater than 200 randomly, a diagnosis of diabetes is made. To confirm whether it is type 1 or type 2 diabetes, blood tests are used to measure antibodies.
- Additionally, a presumptive diagnosis can be made based on glucose or ketones in the urine.
- A c-peptide test can determine how much insulin the pancreas is producing.
- Genetic testing, such as HLA subtyping, can add further understanding of the disease.
What is the treatment for type 1 diabetes? Can it be cured?
Currently, type 1 diabetes cannot be cured. People with type 1 diabetes require injectable insulin because their pancreas does not produce enough on its own. There are different types of insulin and different routes of administration. Most people with type 1 diabetes use both a long-acting insulin (sometimes called a basal insulin), and inject additional insulin before or after meals (sometimes called regular or short-acting insulin) to match the carbohydrate content of the meal. An insulin pump may also be used to optimize insulin delivery to the body's needs.
- Unfortunately, one of the major side effects of insulin is weight gain. People with type 1 diabetes can reduce weight gain by:
- Eating a healthy low-carbohydrate (low-glycemic load) diet,
- Getting plenty of exercise, and
- Learning to use insulin correctly in order to use just the right amount
- Diet and level of activity.
- Because type 1 diabetes is characterized by the loss of insulin production in the pancreas, insulin must be provided in the form of an injection.
- In addition to insulin, treatment includes diet changes to minimize sugars and make sure carbohydrates are matched with the appropriate dose of insulin.
- There are different forms of insulin and different ways it can be administered.
- A type 1 diabetes diet should focus on lots of vegetables and healthy proteins such as fish, chicken, and beans; and should be low in sweets and processed baked goods.
- A healthy diet helps blood sugar control and helps with weight loss.
Is there a type 1 diabetes diet?
The basics of a type 1 diabetes diet include making sure carbohydrate intake is matched with insulin and choosing healthy options to maximize nutrition in each calorie. People with type 1 diabetes will find it is easiest to match carbohydrates to insulin if they follow a low-glycemic load (index) diet, so that the impact of carbohydrates on blood sugar is slow and gradual. This also makes it easier to predict and match to required insulin.
Because weight gain can be a side effect of injecting insulin, a type 1 diabetes diet should be healthy and low in calories to help the person maintain or lose weight. Food lists of low-glycemic load options can help people learn what to include in their diet.
Does exercise affect blood sugar levels?
- Exercise is important for everyone, including people with type 1 diabetes.
- People with type 1 diabetes need to be careful to monitor their blood sugar before, during, and after exercise and have snacks with them in case blood sugar goes too low.
- When people exercise, the muscles use insulin to access blood sugar for fuel.
- This can lead to lower than expected blood sugar.
- Exercise also may trigger release of stored glucose from the liver. This can lead to higher than expected blood sugar. This is why it is important to check blood sugar, especially when beginning a new exercise program.
- People with type 1 diabetes may see their blood sugar go up or down with exercise.
What is the life expectancy for someone with type 1 diabetes?
Research published in the Journal of the American Medical Association reported that people with type 1 diabetes live about 11 years less than average; however, new research also suggests this differential can be reduced with good glycemic control. Most people with type 1 diabetes die from complications of type 1 diabetes such as heart disease or kidney disease. Thus, preventing complications and following a healthy lifestyle that prevents heart disease and controls blood sugar are the best things people with type 1 diabetes can do to live a long, healthy life.
What are the complications of type 1 diabetes?
Uncontrolled blood sugar can lead to a number long-term complications associated with diabetes such as
If you have type 1 or type 2 diabetes you can prevent complications by maintaining a healthy blood sugar level, eating a healthy diet rich in vegetables, and staying physically active.
Can type 1 diabetes be prevented?
While there is not any definitive way to prevent type 1 diabetes, parents can be aware of the risk factors in the prenatal period and in early childhood to minimize risk. For people who already have type 1 diabetes, prevention of complications through good glycemic control and regular medical screening is key.
Which specialties of doctors treat type 1 diabetes?
Adult and pediatric endocrinologists, specialists in treating hormonal disorders and disorders of the endocrine system, manage patients with diabetes. A number of primary care doctors including family and internal medicine doctors, naturopathic doctors, or nurse practitioners also may care for people with type 1 diabetes. When complications arise, people with diabetes often consult other specialists, including neurologists, gastroenterologists, ophthalmologists, surgeons, and cardiologists. Nutritionists, integrative and functional medicine doctors, and physical activity experts such as personal trainers are also important members of a diabetes treatment team.
Medically Reviewed on 8/26/2019
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