It is not caused by eating too much sugar, per se, but it has everything to do with how your body handles the sugar you consume and what you do to manage the level of sugar in your blood.
Types and Prevalence of Diabetes Mellitus, Defined
A number of disorders are grouped under the umbrella of diabetes, usually identified by type. Each type is distinct in terms of what causes it, how it's treated, and the complications that can arise.
Here's a quick look at each type of diabetes: definitions, some fast facts, and how common each type is in the United States and worldwide.
Diabetes 101: What Are the Different Types of Diabetes?
Prediabetes?and Insulin Resistance
Prediabetes is a condition that can lead to type 2 diabetes. To understand what causes it, you have to understand how the body handles sugar (or glucose) and processes it into energy.
Type 2 Diabetes?
Type 1 Diabetes
Type 1 diabetes is an autoimmune disorder in which a person’s own immune system attacks and destroys the beta cells in the pancreas that make insulin. Without that hormone, hyperglycemia develops. People who have type 1 diabetes must take insulin injections to replace the insulin their body doesn’t make, as well as monitor their blood glucose level daily.
Complications of type 1 diabetes are similar to those found in type 2 because in both cases, chronically elevated blood sugar causes long-term damage. But people with type 1 are especially vulnerable to developing a potentially life-threatening condition known as?diabetic ketoacidosis (DKA). When the body doesn’t have enough insulin to convert glucose into energy, it begins to break down fat for fuel. The result is a buildup of acids in the bloodstream known as ketones.
“We typically tell patients that if your blood sugar is above 250 [milligrams per deciliter; mg/dL] you want to test your urine for the presence of ketones — or check if you are going to?exercise?and your blood sugar is above 300 mg/dL. It can be life-threatening, because high levels of ketones in your blood can actually make your blood too acidic,” says?Jordana Turkel, RD, a certified diabetes care and education specialist (CDCES) at Park Avenue Endocrinology and Nutrition in New York City.
Type 1.5 Diabetes
“When you have a patient who is over the age of 30 and they come in with classic symptoms — the blood sugar is pretty high — if you give them metformin, they may be able to still manage some of their symptoms. But within the next five years, those beta cells that are producing the insulin are going to stop working and then they are going to turn into a true type 1 patient requiring insulin,” says Turkel.
‘Type 3 Diabetes’
Signs and Symptoms of Diabetes
If you suspect that you have prediabetes or diabetes because of any of the symptoms below, you'll want to visit your healthcare provider immediately.
How Is Diabetes Diagnosed?
To be tested for prediabetes or any type of diabetes, you'll need to visit your healthcare provider's office. Unfortunately, you cannot test for the disease at home. As a first step in diagnosing you, the healthcare provider will take a medical history, including information about anyone else in your family who has had diabetes and what type. Next, they will likely order lab tests to measure your blood glucose, such as:
Fasting plasma glucose test (FPG)?This test is performed after you’ve had nothing to eat and no more than small sips of water for eight hours. Here’s what the results mean:
- Normal: less than 100 mg/dL
- Prediabetes: 100–125 mg/dL
- Diabetes: 126 mg/dL or higher
- Normal: less than 5.7 percent
- Prediabetes: 5.7–6.4 percent
- Diabetes: 6.5 percent or higher
- Normal: Less than 140 mg/dL
- Prediabetes: 140–199 mg/dL
- Diabetes: 200 mg/dL or higher
Random plasma glucose test (RPG)?This test for diabetes doesn’t require fasting beforehand, and while it can suggest diabetes with results of 200 mg/dL or higher, it is not typically used.
Autoantibody tests?are?most often done to test for type 1 diabetes or LADA. Common tests look for antibodies targeting insulin or certain pancreatic cells.
C-peptide test?measures a protein that mirrors the level of insulin in the body. Low levels can indicate type 1 diabetes or LADA.
Genetic testing for?monogenic forms of diabetes,?such as maturity-onset diabetes of the young and neonatal diabetes mellitus.
Causes and Risk Factors of Diabetes
You can take steps to lower your chance of developing types of diabetes that involve insulin resistance, such as prediabetes, type 2 diabetes, or gestational diabetes. (Type 1 diabetes, an autoimmune disorder in which too little or no insulin is produced, isn’t known to be preventable.)
Diabetes Risk Factors You Can Control
Some of the strongest risk factors for developing insulin resistance are under your control. They include:
- Excess weight, especially a?body mass index (BMI)?of 25 or higher for people in most ethnic groups in the United States; 23 and higher for Asian Americans; and 26 or higher for Pacific Islanders
- A diet that is high in fat, added sugar, and refined carbohydrates
- No regular?exercise
- Tobacco smoking
Diabetes Risk Factors You Can’t Control
- Age 45 or older
- A family history of diabetes
- African American, Alaska Native, American Indian, Asian American, Hispanic/Latino, Native Hawaiian, or Pacific Islander ethnicity
- A history of gestational diabetes or a child with a birth weight of nine pounds or more
- Polycystic ovary syndrome (PCOS)
People should know that they can do things to lower their risk of developing the insulin-resistant forms of diabetes, but they should not feel guilty if they develop the disease anyway, says?Joshua D. Miller, MD, the medical director of diabetes care at Stony Brook Medicine in Stony Brook, New York, who manages a personal diagnosis of type 1 diabetes himself.
“No one wakes up and says they want to develop diabetes, whether it be type 1 or type 2. Developing diabetes is completely out of most people’s control — even along the type 2 diabetes spectrum where lifestyle and obesity play a larger role in developing the disease,” Dr. Miller says. “Working past the notion that you’ve done something wrong because your blood sugar is too high is probably the most important challenge to overcome in order to help people become better at managing their disease.”
Is Diabetes Hereditary? The Role of Genetics in Risk
While your risk score won’t predict with 100 percent certainty whether you’ll develop a polygenic form of diabetes, it may help you focus on taking preventive measures, says Mónica?Alvarado, a certified and licensed genetic counselor who is the regional administrator for genetic services at Kaiser Permanente in Pasadena, California. “The advantage of that is that someone might be more motivated to control their diet and exercise, and to monitor their glucose and hemoglobin A1C more regularly than if they just have information that their risk for diabetes is higher than that of the average person.”
Alvarado also says the influence of family history is complex, and it’s hard to know whether relatives are just sharing genetic variations alone, or also sharing a diet, lifestyle, and environment that make them more prone to developing diabetes.
Treatment and Medication Options for Diabetes
If you’ve been diagnosed with diabetes, your?treatment?regimen will vary based on your individual health and the type of diabetes you’re managing. But one word that's often closely linked with the condition is insulin.
There are two main types of insulin used to get you through the day.
Basal insulin is present in the body 24 hours a day, always in the background regardless of what or when you eat. “It’s what the pancreas would be dripping into the system constantly,” says Grace Derocha, a registered dietitian and a certified diabetes care and education specialist at Blue Cross Blue Shield of Michigan in Detroit.
Long-acting insulin, such as?Detemir (levemir);?Tresiba (degludec); and Lantus, Toujeo, and?Basaglar?(glargine) and intermediate-acting insulin, such as?Humulin N (isophane), Novolin N, and Lente (lente), are slowly released into the bloodstream so they can last up to 24 hours. If someone is on a pump, the amount is adjusted slightly depending on the level of activity or whether someone is awake or asleep, says Derocha.
Instead of or in addition to insulin, a number of oral medications are used to treat diabetes, particularly in people whose bodies still make some insulin.
Meglitinides?Prandin (repaglinide)?is a meglitinide, which also stimulates the pancreas to release more insulin when taken with meals.
Thiazolidinediones?The only approved drug in this class is?Actos (pioglitazone), which makes the body more sensitive to the effects of insulin.
DPP-4 inhibitors?Januvia (sitagliptin)?and Tradjenta (linagliptin) belong to this class. These drugs improve the level of insulin made after a meal and help lower the amount of glucose made by the body.
GLP-1 receptor agonists?Victoza (liraglutide), Trulicity (dulaglutide), and Ozempic (semaglutide) belong to this class of drugs, which mimic the effects of the incretin hormone GLP-1, which is excreted during a meal and lowers blood sugar.
SGLT2 inhibitors?Invokana (canagliflozin)?belongs to this class of drugs, which prompt the kidneys to get rid of more glucose through urine.
There are also continuous glucose monitors that you wear on your arm or abdomen for 10 to 14 days, including Freestlye Libre, Dexcom G6, and Medtronic Guardian.
Diet and Lifestyle Tips to Help Keep Blood Sugar in Check
Depending on the type of diabetes you're managing, you'll need to work with your healthcare team to devise a diet and lifestyle program that meets your individual needs. Then you'll need to build a support team in and outside of the home to help you stay on track.
Eating to Control Your Blood Sugar
“We try to teach carb control, carb consistency, and carb counting,” says Derocha. “I call it the ‘three carbohydrate Cs’ that are important for any type of diabetes and blood sugar control.” In short: Counting your carbohydrates and keeping them at a consistent level for every meal can help you to stabilize and control your blood sugar.
Glycemic Index and Glycemic Load
Some people also look at how various foods containing carbohydrates are likely to raise their blood sugar, according to the food's rank on the?glycemic index (GI) and its?glycemic load (GL).
The glycemic index is a measure of how food raises blood glucose levels. Foods are ranked on a scale of 0 to 100, with 100 being pure glucose (sugar). Low-GI foods rank at 55 or less (such as oatmeal, sweet potatoes, and most fruit); medium-GI foods rank 56–69 (brown?rice?and corn); and high-GI foods (think bagels, popcorn, and melon) rank 70 and above.
“A high-glycemic-index food will raise blood sugar more than a food on the medium or low end of the spectrum,” explains Derocha. But, she notes, “The glycemic load itself is really a better way to tell you how that particular food will then affect your blood sugar.” This is because glycemic?load compares the ability of the same amount of carbs in each food to raise your blood sugar higher.
To figure out a food’s glycemic load, multiply its GI by the number of carbohydrate grams (g) in a serving, and then divide that by 100.
Knowing a food’s specific GL can help you lower and control your blood sugar, but Derocha stresses that it’s most effective to use this strategy in concert with carb counting and healthy eating.
The Ketogenic Diet and Diabetes
Some people with type 2 diabetes will go on a ketogenic diet (also called the “keto” diet), a high-fat, low-carb regimen that forces your body to burn fat instead of carbs for fuel. Because the approach is so low in carbohydrates, the body quickly depletes its store of glucose and then enters a natural state of ketosis, in which fat is broken down by the liver into acids known as ketones, which become the main source of fuel. “For type 2 patients on medication or who have PCOS with insulin resistance, a version of the ketogenic diet can help,” particularly if losing weight is a goal, says Turkel.
But, she adds, people who have insulin resistance are typically trying to manage a lot of diet and lifestyle changes at once to help control their blood sugar, so she doesn’t recommend the rigors of a ketogenic diet as a long-term solution. Additionally, if you are taking oral diabetes medications, you may be at risk of potentially serious complications, like hypoglycemia.
Eating to Control Gestational Diabetes
Derocha says her personal experience with gestational diabetes is that it’s manageable. “During my pregnancies, I did not have to take any medication, and I did not take any insulin, because I was able to control it with my diet and lifestyle changes.”
The Importance of Exercise
As for what you should do for exercise, Happel suggests finding an activity you like and sticking with it. “Make it fun, make it something you enjoy doing,” Happel says. “Do it with family, do it at work. If you like to dance, then dance. Walking, working in the garden — just be active.”
Complications of Diabetes
Poorly managed blood sugar can lead to serious and even life-threatening health complications, regardless of the type of diabetes you have. But there are some specific health risks by type that you should be aware of.
Type 1 and Type 2 Diabetes
A number of complications can arise from types 1 and 2 diabetes if they’re uncontrolled or poorly controlled for a long period of time. They include:
- Damage to blood vessels, resulting in heart disease, stroke, and kidney disease, according to the NIDDK
- Blindness?(including diabetic retinopathy, diabetic macular edema, cataracts, and glaucoma) caused by swelling, nerve damage, or damage to the tiny blood vessels in the eye
- Bladder problems and sexual dysfunction, also due to damage to blood vessels or nerves
- Orthostatic hypotension (a drop in blood pressure upon standing up)?caused by nerve damage, according to Diabetes.co.uk
- Slow-healing wounds, as a result of blood vessel damage
- Diabetic ketoacidosis (DKA), a buildup of acids in the bloodstream known as ketones, occurring when the body doesn’t have enough glucose to use as fuel.
Other Possible Complications of Diabetes
Numerous complications are associated with diabetes mellitus. They include:
Diabetic neuropathy?Nerve damage affects nearly 60 percent of people with diabetes. Distal symmetric polyneuropathy (DSP) is the most prevalent within that group. With this form of neuropathy, the most distant nerve fibers from the central nervous system malfunction first. “It usually starts in the feet; [you’ll] feel tingling or numbness at the bottom of the feet, and then [it] may slowly progress upward in the foot to the ankle and the legs,” says?Happel.
The pattern is usually symmetrical, affecting limbs on both sides. Sometimes, a burning sensation takes hold, which Happel says is sometimes mistaken by patients for?athlete’s foot. Eventually, numbness and then profound loss of sensation can set in, along with the loss of reflexes.
Symptoms of hypoglycemia include jitteriness or shakiness, blurred vision, fatigue, dizziness, disorientation, a fast or irregular heartbeat, irritability, weakness, or extreme hunger. Severely low blood sugar may result in unconsciousness and seizures.
Happel says one reason why people end up with HHNS is noncompliance with their insulin treatment regimen, especially among teens and college students with type 1 diabetes. “They don’t want to be different from their friends, so they don’t take their insulin. Then they go out and have some drinks. Alcohol, when it is broken down in the body, is also broken down into sugars. But they are not taking their insulin, and they wind up in the hospital,” Happel explains.
But people with any type of diabetes are at risk for this complication, especially if they’re insulin-dependent. Noncompliance isn’t the only trigger, either; sometimes a person who develops HHNS is fighting another illness that has weakened and dehydrated them, says Happel.
Treatment generally happens in the ICU. “One of the first things is fluid resuscitation. They are four to six liters of fluid behind by the time they develop these complications,” says Happel. Insulin is administered and electrolyte balances are also addressed. The best way to avoid HHNS is to monitor your blood sugar, take any insulin or medications you are prescribed in the proper dosage, and stick to your diet and exercise plan to manage diabetes.
Gestational Diabetes Complications
Is It Possible to Reverse Diabetes? Answers to FAQs Like This
Short answer: Maybe. Get more details on that common question and others below.
Q: How do I know if I have diabetes?
Q: Does sugar cause diabetes?
A: Not really, but diabetes has everything to do with how your body handles the sugar you consume. Diabetes mellitus is a group of metabolic disorders that cause the level of glucose (sugar) in your blood to be too high. This is called hyperglycemia.
Q: Which is worse: type 1 diabetes or type 2 diabetes?
Q: Is type 2 diabetes genetic? What about type 1 diabetes?
Nonetheless, risk scoring cannot tell you with certainty if you will develop one of the disorders. Family history is another risk factor, but it’s hard to know whether that is due to sharing genetic variations with relatives, or also due to having?a diet, lifestyle, and environment in common.
Q: What does “prediabetic” mean?
Q: Can people with diabetes donate blood?
Taking oral medications and most forms of insulin to maintain that control is okay, but if you have ever used bovine (beef) insulin made from cattle from the United Kingdom since 1980, you are ineligible, because of a concern about Creutzfeldt-Jakob disease, also known as “mad cow disease.” If you're in doubt about your blood sugar level or what insulin you have taken, check with your doctor.
Q: Can people with diabetes eat fruit?
“At one given time you don’t want to have more than 1 cup of cut-up fruit or a cup of berries or one small piece of fruit,” Turkel advises. “And you never want to eat a piece of fruit or cup of fruit without a protein or a fat.” Adding protein or fat slows down the impact of the fruit’s sugar in your bloodstream and lessens the chance of a spike in blood sugar. “If you like fruit, pair it with some protein — a handful of nuts, a hard-boiled egg — and be strategic about it. And limit it to only twice a day.”
Q: What is a “diabetic diet”?
Q: What foods should people with diabetes avoid??
Q: Can people with diabetes get tattoos?
A: Yes, but you should check with your doctor first, and be sure of a few things, says Derocha. “Obviously you would not do this if you were pregnant [and have gestational diabetes], but with type 1 or type 2, you’d really have to have good blood sugar control. That is because one of the side effects of poor sugar control is an inability to heal [well] and to fight off infection.”
Q: What is diabetes insipidus?
Q: What does diabetic nerve pain feel like?
Q: Can dogs get diabetes?
Q: Can you die of diabetes?
Q: Can diabetes cause low blood sugar?
Signs that your blood sugar has dropped can include feeling shaky or jittery; having blurred vision, fatigue, dizziness, disorientation, fast or irregular heartbeat; being irritable; and feeling weak or extremely hungry. If left untreated, hypoglycemia can result in unconsciousness and seizures.
If you have diabetes, check your blood glucose if you notice any of these symptoms and if your number drops below 70 mg/dL (or the target you’ve set with your doctor), and then take in 15 g of carbohydrates right away, and then check your blood glucose 15 minutes later. Repeat this until your blood glucose is on target. This is called the rule of 15s. If it doesn’t help you meet your target after several attempts, use oral glucose.
Q: Can diabetes be reversed?
Additional reporting by Moira Lawler.
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