Diabetes mellitus, or diabetes, is a chronic disease that impacts the pancreas, the organ responsible for producing insulin.
Insulin is a hormone necessary for regulating blood sugar levels. Glucose (sugar) is obtained through the diet and stored in the liver to be released when needed or in times of stress.
Without enough insulin, sugar cannot enter the body’s cells to use as energy, leaving it to accumulate in the bloodstream. Chronic high blood sugar can cause many complications such as an increased risk of heart disease, kidney disease, nerve damage, poorly healing wounds, and many other conditions.
Diabetes is increasing in prevalence worldwide. As of 2015, 30.3 million people in the United States, or about 9.4 percent of the population, had diabetes. The global incidence of diabetes has also increased from 4.7% in 1980 to 8.5% in 2014. The majority of those with diabetes have type 2 diabetes, while only about 5% of those with diabetes have type 1.
Many people also have prediabetes, a condition where blood sugars are slightly elevated but not high enough to be considered diabetes. Having prediabetes is a significant risk factor for eventually developing type 2 diabetes.
The U.S. Centers for Disease Control (CDC) estimates that up to 30% of people with prediabetes will develop type 2 diabetes within five years of their prediabetes diagnosis.
While people often refer to both types of diabetes as just “diabetes,” type 1 and type 2 diabetes are different in many ways. While there are some similarities between them, they should not (and cannot) be treated the same. Type 2 diabetes is associated with more well-known risk factors, whereas type 1 diabetes’s risk factors remain somewhat unclear.
Type 1 and type 2 diabetes are two distinct conditions
Blood glucose, or blood sugar, is the main energy “currency” used by the body’s cells. In order for the glucose to enter the cell, it requires a hormone called insulin, which is produced by the pancreas.
Cells have insulin receptors that insulin can bind to, letting the glucose enter the cell from the bloodstream. Another way to think of it is that insulin is the key to enter the cell “door,” which has an insulin receptor “doorknob.”
In someone without diabetes, the pancreas produces enough insulin to help keep the levels of sugar in the bloodstream at a healthy level. The liver also releases sugar to help keep blood sugars from falling too low (hypoglycemia), such as during periods of fasting.
Type 1 and type 2 diabetes result from a lack of insulin and increased blood sugars. The liver can also release too much sugar in people with diabetes, further worsening the high blood sugar. The ways type 1 and type 2 diabetes occur are very different.
Type 2 diabetes usually occurs from insulin resistance, when cells don’t respond to or use insulin effectively. This can lead to an insulin deficiency from the pancreas working harder to produce more insulin in response to high blood sugar levels. Without enough insulin, the glucose molecules are unable to enter the cells as they should. When this occurs, glucose accumulates in the bloodstream and leads to hyperglycemia or high blood sugar. The body’s process of becoming insulin resistant can occur over several years, gradually reducing the body’s ability to produce enough insulin.
People with type 2 diabetes don’t usually lose the ability to produce insulin entirely. The pancreas of someone with type 2 diabetes might not make enough insulin, but it still can create some. This is another major difference between the two types of diabetes.
Type 1 diabetes is an autoimmune disease. An autoimmune disease is one where the body’s immune system mistakenly views healthy parts of the body as foreign and works to destroy them. While this process is useful in the presence of an actual foreign invader, such as a virus, it is devastating when healthy parts of the body are attacked.
Specifically, the beta cells of the pancreas are targeted and destroyed in type 1 diabetes. The beta cells are the ones responsible for producing insulin. Once the beta cells are destroyed, the damage is irreversible. Unlike type 2 diabetes, people with type 1 diabetes are insulin deficient, meaning their pancreas isn’t able to produce insulin. This is why people with type 1 diabetes must take insulin, whereas people with type 2 diabetes can sometimes manage it with lifestyle changes alone, or they can take medications other than insulin.
The risk factors for type 1 diabetes aren’t as well-understood as type 2 diabetes because of its nature as an autoimmune disease. Some of the known risk factors for developing type 1 diabetes include:
- Family history: people with a parent or sibling with type 1 diabetes are more likely to develop it than people without a family history.
- Genetics: certain genes tend to indicate an increased risk of type 1 diabetes.
- Geography: incidence of type 1 diabetes tends to increase as the distance from the equator increases.
- Age: the first peak of diagnosis tends to occur between ages 4-7 and again between ages 10-14. This is one of the reasons type 1 diabetes is often referred to as juvenile-onset diabetes.
Symptoms of type 1 diabetes
The symptoms of type 1 and type 2 diabetes are often very similar. The symptoms arise as a result of the body trying to rid itself of the excess glucose. The symptoms of type 1 diabetes can have a sudden onset and include:
- Increased thirst
- Frequent urination
- Bed-wetting in children who previously didn’t wet the bed during the night
- Extreme hunger
- Unintended weight loss
- Irritability and other mood changes
- Fatigue and weakness
There are several blood tests available to determine if someone has diabetes. To differentiate between type 1 and type 2 diabetes, antibody tests can be ordered to see if there is immune system involvement, which would indicate type 1. Some antibody tests that can be used to diagnose type 1 diabetes include C-peptide, IAA, IA-2A, ZnT8Ab, ICA, and GADA anti-GAD.
In addition to antibody tests, healthcare providers will usually run other blood tests to determine how high blood sugar levels are.
Fasting blood sugar, random blood sugar, and hemoglobin A1c are all commonly used. A fasting blood sugar of 126 mg/dL or greater, hemoglobin A1c of 6.5% or greater, and/or a random blood sugar of 200 mg/dL or greater are all indicative of diabetes.
Some people may find out they have undiagnosed type 1 diabetes for the first time after experiencing a serious condition called diabetic ketoacidosis, or DKA. DKA occurs when insulin levels fall so low that the body starts burning ketones for fuel instead of glucose.
Some of the warning signs of DKA include:
- Thirst or a very dry mouth
- Frequent urination
- High blood glucose (blood sugar) levels
- High levels of ketones in the urine
Other symptoms can appear as DKA worsens:
- Constantly feeling tired
- Dry or flushed skin
- Nausea, vomiting, or abdominal pain
- Difficulty breathing
- Fruity odor on the breath
- Hard time paying attention, or confusion
Left untreated, DKA can lead to a diabetic coma or even death, which is why people with DKA should be evaluated by a medical provider urgently.
Tips for living with type 1 diabetes
1) Build your care team
Managing type 1 diabetes can be especially challenging; even people who have had type 1 their whole lives can still experience erratic blood sugar shifts due to hormonal changes, stress, and many other factors.
Along with a primary care provider, people with type 1 diabetes should also consider adding the following healthcare providers to their care team:
- Endocrinologists are healthcare providers who specialize in conditions pertaining to hormones such as insulin. Endocrinologists can also guide their patients on correctly dosing their insulin and offer guidance when using an insulin pump.
- Diabetes educators specialize in diabetes care and education. They should be certified as a Certified Diabetes Care and Education Specialist (CDCES) to prove they have met the education and experience requirements to earn their credential. Diabetes educators can be especially helpful early on after the initial diagnosis to help guide parents, family members, and other caregivers on how to best support the person with type 1.
- Ophthalmologists are eye doctors who can determine if any damage has been done to the eyes, such as in the case of diabetic retinopathy. People with retinopathy can lose vision or even become blind, which occurs from damage to the vessels in the eyes due to prolonged high blood sugar.
- Registered Dietitians (RD/RDN) are nutrition professionals who have met specific education criteria and have been trained to help people navigate conditions like diabetes. RDs can help people with type 1 diabetes make food choices to promote healthy blood sugar levels and avoid low blood sugar. People with type 1 diabetes should choose a dietitian who can help them make sustainable lifestyle changes; fad diets or extreme restrictions usually can’t be maintained and can be detrimental to health.
- Podiatrists specialize in issues with the feet. People with type 1 diabetes are more prone to foot ulcers and other foot injuries, which can lead to amputations if not treated correctly. Podiatrists can help people avoid these problems and may even prescribe special diabetic shoes.
- Mental health care providers can help people with type 1 diabetes navigate the stress and challenges of their disease. People with type 1 are more likely to suffer from anxiety, depression, and disordered eating.
2) Be able to identify and treat low blood sugar
Hypoglycemia is the term for low blood sugar, which occurs when blood sugar falls below 70 mg/dL. Hypoglycemia is more common in people taking insulin, such as those with type 1 diabetes. Symptoms of hypoglycemia include:
- feeling shaky
- feeling disorientated
- being anxious or irritable
- going pale
- palpitations and a fast pulse
- lips feeling tingly
- blurred vision
- being hungry
- feeling tearful
- having a headache
- lack of concentration.
Hypoglycemia is most effectively treated with glucose tablets, drinking fruit juice, or injecting glucagon in more severe cases. Glucagon is a hormone that increases the amount of sugar released from the liver. A glucagon injection can be prescribed for someone with type 1 diabetes to have on hand in the case of severe hypoglycemia when they may not be able to consume food or drink containing sugar.
Family members and friends should also be trained on hypoglycemia warning signs to support the individual with type 1.
3) Consider using an insulin pump and/or a continuous glucose monitor (CGM)
An insulin pump delivers insulin automatically and continuously via a device worn under the skin. The insulin pump acts to mimic a pancreas, minimizing the need to inject multiple doses of insulin each day.
A continuous glucose monitor is another device worn under the skin that measures blood sugar levels every 5-15 minutes. This is useful for identifying trends in blood sugar levels and can also help predict and identify hypoglycemia sooner. Using a CGM can reduce the amount of finger prick glucose tests someone with type 1 needs to perform each day.
CGMs and insulin pumps can require certain criteria to be met before they are provided through healthcare insurance.
4) Check blood sugar often
For those not using an insulin pump, blood sugar levels should be monitored several times a day to ensure good blood sugar control. It’s also important to know how blood sugar levels change during the day to adjust best basal (long-acting) and bolus (short-acting/mealtime) insulin. Common times to check blood sugar levels for someone with type 1 can include first thing in the morning (fasting), before and/or after meals and snacks, before and/or after exercise, and at bedtime.
5) Be smart about exercise
Exercise is beneficial for helping to control blood sugar in those with type 1 and type 2 diabetes. However, suppose blood sugar levels are very high, and there are ketones present (tested with a simple at-home urine test strip) prior to exercising. In that case, exercise should be avoided until blood sugars are stabilized. Exercise can increase blood sugars in the initial stages, which would worsen existing very high blood sugars and could even lead to diabetic ketoacidosis in someone with type 1 diabetes.
Type 1 diabetes is an autoimmune disease where the insulin-producing cells of the pancreas are destroyed. People with type 1 diabetes are usually diagnosed in their childhood years, giving it the name “juvenile-onset diabetes.”
People with type 1 diabetes must inject insulin because their pancreas doesn’t control blood sugar levels. Unlike type 2 diabetes, people with type 1 don’t suffer from insulin resistance, and developing type 1 isn’t associated with lifestyle habits such as being overweight, being sedentary, etc.
Managing and living with type 1 diabetes can be complicated, requiring a comprehensive care team including healthcare professionals such as endocrinologists, diabetes educators, dietitians, and mental health professionals. Increasing technology can also help simplify diabetes care, such as using insulin pumps and continuous glucose monitors.