Symptoms, Causes, Diagnosis, Treatment, and Management of

Type 1 Diabetes
Also called Juvenile Diabetes, Childhood Diabetes
and Insulin-Dependent Diabetes Mellitus

"Never regret. If it's good, it's wonderful.
If it's bad, it's experience."

         Victoria Holt

What is Type 1 Diabetes?

There is more than one form of type 1 diabetes and each can develop for different reasons.  Type 1 diabetes can result from hereditary deficiencies in the beta-cells of the pancreas (maturity onset diabetes of the young, or MODY),  damage to the pancreas from trauma or drugs, another illness like hemochromatosis (iron overload) or cystic fibrosis that damages the pancreas, or will result when the pancreas is surgically removed.

The most commonly diagnosed form of type 1 diabetes is juvenile diabetes, or, insulin-dependent diabetes.  People with juvenile type 1 diabetes have an inherited genetic predisposition towards developing diabetes (the genes are different for type 1 and type 2 but both have a genetic aspect involved).  Many people have these genes but will never develop the disease. For those that do become diabetic, something triggers the body to attack and destroy the insulin producing beta cells in the pancreas.  

Triggers for type 1 diabetes are thought in include certain viruses (including rotaviruses), chemical, or some other environmental factor.  Visit our general diabetes information page for causes of diabetes, genetic transmission rates of diabetes for type 1 and type 2 diabetes, and other diseases and disorders that are associated with diabetes.

Other diseases that affect persons with diabetes at a higher rate than in the general population include Addison's Disease, Hashimoto’s Thyroiditis. celiac disease (sprue, or gluten intolerance), and polycystic ovarian syndrome.  Anyone diagnosed with type 1 diabetes should also be tested for these.

Juvenile type 1 diabetes is an autoimmune disease.  An autoimmune disease is when the body attacks and destroys good cells and tissues mistaking them as foreign intruders.  With type 1 diabetes the insulin-producing beta cells in the pancreas are slowly destroyed and eventually they fail to produce insulin.  When this happens a person will need to take insulin to live.  

Other Names for Juvenile Type 1 Diabetes

Other names (most of which are considered outdated) include childhood diabetes, insulin-dependent diabetes mellitus (IDDM)  (diabetes mellitus is a group of autoimmune metabolic disorders all of which include hyperglycemia), and ketone prone diabetes.  It is important to note that type 1 diabetes and type 2 diabetes are not the same thing, however, some people can have both types, and people with type 2 can eventually become type 1 diabetic. 

All type 1 diabetics must take insulin to live while only some type 2 diabetics require insulin.  Type 1 onset is usually fast, over days or weeks, and although most often diagnosed in children can occur at anytime in life even in adulthood.

Subtypes of Type 1 Diabetes

Type 1 diabetes has several subtypes, including type 1A diabetes, type 1B (idiopathic diabetes), and latent autoimmune diabetes of adulthood (LADA).  LADA may be initially misdiagnosed as type 2 diabetes because onset is usually much slower than in juvenile diabetes and diagnosis of LADA is most likely to be after age 25.

Maturity Onset Diabetes of the Young (MODY), another form of type 1 is not the same as juvenile type 1 diabetes, but is treated the same way (with blood glucose monitoring and insulin).  Persons with MODY may require only very small amounts of insulin because their pancreas may still produce some insulin.  It can be misdiagnosed as juvenile diabetes because it is so similar and usually occurs prior to age 25.  Persons with MODY often test negative for thyroid antibodies and may have polycystic kidneys as part of the disease.  There is more than one type of MODY and specific treatment varies.

Type 1 subtypes are treated basically in the same manner as type 1 diabetes with stress management, lifestyle changes, and insulin.     

Diagnostic Criteria for Type 1 Diabetes 

A person with two fasting plasma glucose levels of 126 mg per dL (7.0 mmol per L) or greater is considered to have diabetes mellitus.  Some doctors may use a postprandial (after eating) test instead where blood glucose is measured 2 hours after 75 g of glucose is given.  Any 2-hour postprandial reading over 200 is considered diabetic.  And any two casual readings of 200 mg/dL or higher is also considered diabetic.

The fasting glucose tolerance test is generally preferred for diagnosis, however, any two abnormal tests are sufficient to classify a person as diabetic.  Additionally:

  • Type 1 diabetes mellitus is characterized by beta cell destruction caused by an autoimmune process, usually leading to absolute insulin deficiency (the pancreas makes no insulin).  Onset is rapid, usually occurring over a period of days or weeks.
  • Over 95 percent of persons with type 1 develop the disease before the age of 25.  Persons who develop type 1 diabetes over the age of 25 may be diagnosed with Latent Autoimmune Diabetes of Adults (LADA).  Sometimes, LADA, which may also be called "slow onset diabetes" or type 1.5, is initially misdiagnosed as type 2 diabetes.
  • There is an equal incidence of diabetes mellitus in both sexes, but an increased prevalence is seen in caucasians.
  • A family history of type 1 diabetes mellitus, celiac disease (gluten enteropathy) or other endocrine disease such as Polycystic Ovarian Syndrome (in women), or Hashimoto’s Thyroiditis, is often found in those with “immune-mediated form” of diabetes mellitus.
  • Persons with type 1 diabetes have in increased risk of having Addison’s disease, vitiligo, Polycystic Ovarian Syndrome (PCOS), Hashimoto’s Thyroiditis, Celiac Disease, or pernicious anemia.  All persons diagnosed with type 1 should also be tested for antibodies for Hashimoto’s thyroiditis and for celiac disease.
  • Some, usually those of African or Asian origin, have no antibodies but because they meet clinical criteria for diabetes they are classified as having idiopathic type 1 diabetes.

What is considered normal blood glucose range?  

  • Morning Fasting Blood Glucose of  less than 110 mg/dL  
  • 2 hour Postprandial (after eating) of less than 140 mg/dL

What if you are not in the normal range, but not in the diabetic range?

Blood glucose levels higher than normal, but lower than diabetic ranges, classify a person as having impaired glucose homeostasis, specifically as follows:  

  • People with fasting glucose levels from 110 to 126 mg/dL have impaired fasting glucose (FG), or pre-diabetes.
  • People with 2 hour postprandial (two hours after being given glucose) blood glucose levels between 140-200 mg/dL have impaired glucose tolerance (IGT), or pre-diabetes.

Both IFG and IGT are associated with an increase risk in developing type 2 diabetes and lifestyle changes, including weight loss and an exercise program, as well as possible oral medications such as Glucophage are sometimes indicated.

It is important to note that while there is no cure for type 2 (or type 1) diabetes, pre-diabetes can often be completely reversed with proper medical intervention and changes in lifestyle.    

Daily Concerns With Type 1 Diabetes

Type 1 diabetes must be managed on a daily basis.  This includes monitoring blood glucose frequently, following a healthy lifestyle and food plan, testing urine for ketones, and most importantly, thinking long term.  How you manage your diabetes on a daily basis will have tremendous impact on health years down the road.

Daily concerns of type 1 diabetes include watching for, and dealing with, hypoglycemia (low blood glucose), and hyperglycemia. Both can present dangerous situations immediately, on unchecked, can also present possibility of long-term complications as well.

Hypoglycemia (think "O" is in too low) is when blood glucose becomes too low to be healthy or safe. Your doctor should help you determine what constitutes a mild versus a severe low.  In children, a critical low may be set at 60 or 70 mg/dl, an adult might not be considered critical until a low of 50 mg/dl.  

What is considered low varies between individuals as well as time of day, when insulin was last administered, and level of activity.  Medically speaking, a reading of 40 mg/dl or lower is always considered critical for anyone with diabetes.  If blood glucose becomes too low a person becomes disoriented, may experience seizures, loss of consciousness, and even death.

Hyperglycemia (think HIGH-per) is too much blood glucose in the blood stream.  Over time, hyperglycemia can cause serious damage, cells, and organs resulting in diabetes complications.  It can also lead to a state called diabetic ketoacidosis (DKA) that can results in coma or death.

Long-Term Complications of Diabetes

Complications of diabetes are grim and include heart disease, blindness, high blood pressure, nerve damage, diabetic retinopathy (which can lead to blindness), amputation, and kidney failure. But it is possible to maintain tight control over diabetes and help reduce the risk of long-term complications.  High blood glucose over time destroys nerves (neuropathy) and tissues (see image below).  Blood glucose kept in good target ranges will help preserve organs, eyesight and improve longevity.  To better understand why it is important to test your blood glucose often (read diabetes statistics).

Lifestyle Management

Since heart disease is present in more than 75% of all diabetes-related deaths it is important to adopt a healthy lifestyle if you are diagnosed with anyo form of diabetes.  Your doctor may have you consult with a dietitian or nutritionist to help you prepare an exchange plan, or to learn how to count carbohydrate, fat, and protein.  Limiting refined carbohydrates is something everyone should strive for, especially those who are diabetic.  They provide empty calories and require insulin in order to eat.  The exception to eating pure sugar is when fast sugars are required to correct low blood glucose levels.

An important part in keeping blood glucose levels in target range is how you eat and your level of activity.  Even with an insulin pump, which allows more freedom to eat when you want and what you want than do shots, a healthy diet is still very important to combat the high risk of heart disease later on down the road.  Carbohydrates require insulin but so can high fat diets because they can cause blood glucose levels to stay elevated longer.  Also, fatty foods should never be consumed when taking fast sugars to bring up low blood glucose levels because fat will slow down a quick rise in glucose levels.

Understanding how to eat for your particular type of diabetes is key to good health but can be confusing at first.  Type 2 diabetics may need to drastically curtail carbohydrate consumption in general and/or take oral medications to handle carb loads.  While type 1 diabetics should watch the type of carbohydrate they eat,  they need to include plenty of healthy  low-glycemic (long-acting) carbohydrates in their diets -- especially if taking shots and when physically active.

Exercise is a vital part of ensuring long-term health when living with diabetes.  This is particularly true for type 2 diabetics. Exercise increases insulin sensitivity, a problem with some type 2 diabetics and those with Metabolic Syndrome X, insulin resistance, pre-diabetes, and polycystic ovarian syndrome (PCOS).

Medical Treatment
First, it must be said that insulin is not a cure; it is a replacement of a hormone found naturally occurring in the body. Anyone who does not make sufficient insulin (or produces none at all)  will have to take insulin every day.  There are three basic ways of administering insulin:  by syringe (shot therapy), by insulin pump, or by inhalation (the FDA recently approved the use of inhaled insulin).

Treatment for diabetes is multi-faceted, involving insulin, lifestyle changes, stress management, and patient education. Read our section on "Treatment" at for complete information.

Why Insulin?

Insulin is a hormone normally produced in the pancreas and is necessary for the body to properly use blood glucose (sugar).  Insulin acts like a key to open cells and let blood glucose enter.  Without insulin, cells are deprived of glucose, and  cells and tissues begin to breakdown, and the brain is starved of vital energy. 

When glucose builds up in the blood stream it is toxic to all organs and tissues in the body.  Glucose levels can become high enough to induce coma and death.  High blood glucose levels are associated with increased thirst and frequent urination and sweating as the body attempts to rid itself of the excess glucose.  Moderate to heavy ketones present in the urine (an indication of high blood glucose levels) may require immediate medical attention in order to avoid diabetic ketoacidosis (DKA).

Stress Management

Diabetes is stressful all by itself, but uncontrolled stress can lead to high blood glucose.  When the body and emotions are put to the test hormones kick in to help. These hormones can raise blood glucose levels, and can do so rather significantly. The non-diabetic releases these same stress hormones but has functioning mechanisms to keep blood glucose in check that are either absent or do not work properly in diabetics.  

It is important to check your blood glucose during stressful events, such as car accidents (even a minor fender bender), arguments, disappoints like losing a job, or before competitions and speaking engagements -- anything that makes you uneasy or overly excited.  It is not uncommon for persons with diabetes to experience elevated blood glucose from "good" stress such as when reacting positively to a love interest.  It is well documented that teens may only look at someone they have an interest in and experience a surge in blood glucose elevation.  My own daughter (at age 6) developed a young school girl crush on her male teacher's assistant.  The first few weeks of school her blood glucose would jump to nearly 500 within minutes of talking with him.  Excitement in children may also cause a drop in blood glucose levels.  This is more commonly seen in children around holidays and birthday parties.

Many things tax our patience and sap our energy.  It is important to not let yourself get run down physically or emotionally. Take breaks for yourself and find activities and people that you enjoy.  People relax in many different ways, deep breathing, counting to 10, meditation, hobbies, prayer, but one thing all people can benefit from is regular exercise.  This is due in part to levels of cortisol, a stress hormone remains in the system for hours after release.  Exercise will help reduce toxic levels of "bad" hormones and aid in producing "good" hormones that help the body and mind to relax.

If you find your blood glucose is out of control (too high) and you cannot isolate something in your eating and medical plans, look for areas of stress that you can reduce or find better ways to cope with.  Illness also puts strain on the body's systems and can also elevate blood glucose.  Whenever you are sick you should check your blood glucose more often and have a sick-day plan prepared for you by your doctor -- before you get sick.

It is important that you always call your doctor if you are having a hard time keeping your blood glucose in range.

Important Medical Disclaimer

Material on this site is intended for your informational purposes only and should not be used for self- diagnosis or self-treatment. The IOH strongly recommends you seek the advice of a competent medical professional for diagnosis and treatment options, or before making any changes to your diabetes care plan.