Diabetes mellitus is a condition where your body cannot properly process glucose. Your pancreas usually helps your body move sugar from the bloodstream into your cells for energy. With diabetes, your body has an issue with insulin production, or your body’s cells don’t properly respond to insulin.
There are three main types of diabetes, although most people are only familiar with two. They differ in their cause and onset.
Type 1 diabetes is a congenital autoimmune disorder that causes the pancreas not to produce enough insulin. This is the rarer kind of diabetes, and symptoms typically develop early in life.
However, it is possible to develop type I diabetes in adulthood. It was previously called juvenile-onset diabetes, but that term was retired as we gained more understanding of the condition and how it develops. Another term you might hear is insulin-dependent diabetes.
Type 1 diabetes represents up to 10% of the diabetes cases reported and is relatively rare.
Type 2 diabetes is the most common form and develops with age. In type 2 diabetes, your body does not respond properly to insulin, or your body isn't producing enough insulin. The former is called "insulin resistance."
Type 2 diabetes generally develops slowly over time.
Prediabetes is when your blood sugar is higher than normal but below the threshold for diagnosis with type 2 diabetes. You can often reverse prediabetes with lifestyle changes.
Gestational diabetes is a complication of pregnancy that develops in pregnant women who have never had diabetes. This is typically transitory and goes away after the child is born. However, it increases the risk of type 2 diabetes later in life. In fact, about 50% of people with gestational diabetes develop type 2 diabetes within 5–10 years.
Gestational diabetes is caused by hormonal changes during pregnancy leading to insulin resistance.
In 2019, 11.3%¹ of the US population had some form of diabetes. Officially, it was the seventh leading cause of death, but counting diabetes-related deaths can be challenging because it often leads to other diseases.
About 8.5 million adults with diabetes may be undiagnosed. Diabetes is most common in older people.
Symptoms of type 1 tend to come on quickly, although they can take months or years to appear. Symptoms include:
Frequent urination, including bed-wetting in children who have not shown it before
Unintended weight loss
Irritability and mood changes
Fatigue and weakness
Symptoms of type 2 diabetes tend to develop more slowly, and many people are diagnosed by routine screening of blood sugar before they encounter symptoms. They are similar to those for type 1 and include:
Unintended weight loss
Sores that are slow to heal
Peripheral neuropathy, i.e., numbness or tingling in the hands or feet
Areas of darkened skin around the armpits and neck
Prediabetes normally has no symptoms and is diagnosed through routine screening. It should be considered a warning sign that you are at risk of diabetes.
Doctors screen all pregnant people for gestational diabetes. In most cases, gestational diabetes has no symptoms and is detected through routine screening. The two known symptoms are increased thirst and more frequent urination, but it often goes unnoticed as the latter is normal during pregnancy.
First of all, diabetes is incurable, and you cannot prevent type 1 diabetes yet. Type 1 diabetes appears to be a genetic disorder. However, type 2 diabetes is considered a lifestyle disease. It can either be prevented or slowed down.
Over time, elevated blood glucose levels lead to various significant complications, including:
High risk of heart disease
High risk of stroke
Kidney problems, where high levels of blood sugar being filtered put a lot of strain on the kidneys
Diabetic retinopathy, where the high blood sugar levels damage the retina and cause vision loss
Peripheral nerve damage
Foot problems, including the potential risk of amputation
Poor oral health, including more cavities and gum disease
In the case of gestational diabetes, if it is not treated, it increases the risk of:
Premature delivery, sometimes accompanied by respiratory distress syndrome
Excessive birth weight, potentially resulting in difficult labor, birth injuries, or the need for an emergency C-section
High blood pressure and pre-eclampsia, i.e., a dangerous pregnancy complication that can result in the need for elective early delivery
Hypoglycemia in the baby resulting in seizures
Potential obesity in the baby
Type 2 diabetes risk in the baby later in life, with a particular risk for early-onset diabetes (before age 22)
Type 1 diabetes in the baby
Proper treatment and management can reduce all these risks, although not necessarily to zero.
You are more likely to develop type 1 diabetes if you:
Have a parent or sibling with the condition
Are given cow's milk before the age of 12 months (as associated with T1 diabetes)
Had certain viral infections, including rubella, coxsackie, and mumps
Have another autoimmune disease, especially multiple sclerosis, pernicious anemia, or Graves' disease
The known risk factors are:
Gestational diabetes in your gestational parent
Age 45 or older
High blood pressure
Low level of good cholesterol or high level of triglycerides
Had gestational diabetes or gave birth to a baby weighing 9lbs or more
History of heart disease or stroke
Polycystic ovary syndrome (PCOS)
Acanthosis nigricans, a condition that causes the skin to darken and thicken in places
Race, i.e., being Black, Alaska Native, Native American, Asian American, Hispanic, Latino, Native Hawaiian, or Pacific Islander
The good news is that you can control many of these risk factors. The best way to reduce your risk of type 2 diabetes is to stay physically active. This can keep your weight down, balance cholesterol levels, and reduce your risk of depression.
The risk factors for gestational diabetes are similar with the addition of prior delivery of a high birth weight baby.
You should see a doctor if you have any of the symptoms above, many of which can also be signs of another health disorder. For example, frequent urination can be caused by various factors, including pregnancy, a urinary tract infection, urinary tract stones and STIs, or something as minor as drinking too much carbonated soda.
Everyone should have their blood sugar and cholesterol levels regularly checked as there are huge benefits to detecting diabetes early. The American Diabetes Association recommends annual testing starting at the age of 45, but if you have risk factors such as obesity or family history, they may suggest starting earlier. Pregnant women should be screened during the second trimester or first if they have risk factors.
As of right now, there is no cure for type 1 diabetes, and the only treatment is supplemental insulin, which is used daily. This is either in the form of injections or a worn insulin pump. There is no way to prevent type 1 diabetes, although given the potential link to viral infections, getting all recommended vaccinations may help.
You or your child will need to check your blood sugar regularly and keep your blood sugar levels as close to the target. Type 1 diabetics will often have ‘sick day’ action plans to follow when they become unwell with an infection. People with type 1 diabetes are also advised to manage stress, get regular physical activity, and get enough sleep.
Type 1 diabetics are at risk of a hypoglycemic coma, which typically happens if they give themselves too much insulin. Insulin dosage has to be balanced with planned physical activity and food consumption. Symptoms of hypoglycemia include:
Nervousness or anxiety
If you start to experience these symptoms, it's vital to eat or drink something with sugar as quickly as possible to get your blood sugar levels up quickly. Most people with type 1 diabetes carry a sugary drink or glucose pills in the event of an emergency. If somebody goes into a coma, you should call 911.
Most people with type 1 diabetes can lead a normal life as long as they take insulin on schedule.
However, there is a lot of research going on to manage type 1 diabetes. Pancreatic islet transplantation is a promising treatment.
While still experimental, this treatment involves injecting healthy pancreatic cells from a donor into a vein that carries blood to the liver. This typically requires more than one procedure but can result in no longer needing insulin. However, it requires immunosuppressants, which increases your risk of getting infections.
As of right now, it is mostly being recommended for people with major difficulty controlling their blood sugar or simultaneous with a kidney transplant. It's also hard to get donor pancreases, as most pancreases from deceased donors are not in a good enough condition to produce healthy islets.
Candidates for islet transplantation can join an appropriate clinical trial at a special facility. Search for active diabetes clinical trials.
Type 2 diabetes is more complicated. While some people with type 2 diabetes need insulin therapy, others don’t. All older adults should be monitored for increased blood glucose, and those with a family history should pay particular attention.
Many doctors now also monitor cholesterol levels, as a sudden increase in triglycerides can indicate incipient prediabetes. This screening is designed to spot people with prediabetes or insulin resistance before developing into diabetes.
In many cases, lifestyle changes can prevent prediabetes from becoming diabetes and even reverse it. Lifestyle changes are always the first line of treatment for type 2 diabetes. This typically means increasing physical activity, quitting smoking, and eating a healthy diet.
Most people with prediabetes or type 2 diabetes will be referred to a dietician to help them develop a sustainable healthy eating plan that they can keep up with for the rest of their lives. Nevertheless, many people with type 2 diabetes take medication to control their condition.
Medication is more likely to be prescribed for people who are younger at the age of diagnosis. In older people (70 and above), the long-term damage caused by slightly elevated blood sugar is generally not an issue. However, in those diagnosed at 40 or 50, it's very important to keep blood sugar levels down. You may also be prescribed other medication to lower associated risks.
Direct medication for blood sugar, called antidiabetics, falls into several categories, which are typically prescribed when lifestyle changes are not bringing blood glucose down to target levels. Most antidiabetic medications carry the risk of hypoglycemia, especially when used in combination. These medications include:
Metformin is the most common and best-studied anti-diabetic medication and one of the best tolerated. It has been used for many years, and the common side effects are an upset stomach and diarrhea. Usually, these side effects can be controlled by always taking your metformin with food.
A rare complication is an acidosis, where blood becomes too acidic and leads to breathing problems, circulatory shock, and nausea. Metformin is thus contraindicated for people with decreased heart or kidney function or for alcoholics. Metformin works by reducing the amount of glucose your body produces.
Sulfonylureas help your pancreas produce more insulin and have also been in use for some time. They only work for people who still have some pancreatic function and are not indicated for people whose primary issue is using insulin, not producing it.
They have a higher risk of hypoglycemia as they can make your pancreas produce too much insulin. They can also cause weight gain at the start of treatment.
Most glitazones have been taken off the market, but one remains — pioglitazone. This drug helps your body respond better to insulin and is sometimes used with insulin. However, it is not a first-choice drug for several reasons.
It can cause or exacerbate congestive heart failure and should not be used if you have symptomatic heart failure. It's also contraindicated for people with diabetic ketoacidosis and liver impairment. There's some indication of a link to bladder, prostate, or pancreatic cancer, along with a long list of other issues that include eye problems, increased fracture risk in females, and causing ovulation in females who aren't ovulating — potentially resulting in a high-risk pregnancy.
Pioglitazone is typically used only when other drugs have failed, and the benefits outweigh the risks. It can be useful in some situations. It only works if you have sufficient insulin or are on insulin therapy.
Glinides also increase insulin production, similar to metformin. They tend to be second-line drugs as they have a higher risk of hypoglycemia and weight gain, so many doctors prescribe them when metformin is not well tolerated.
Gliptins are also called DPP-4 inhibitors, and they work by blocking the enzyme DPP-4, leading to increased insulin production. Again, they tend to be less well tolerated than metformin and can cause headaches and GI problems, but they are a good option for people for whom metformin is not a good choice.
Gliflozins or SGLT2 inhibitors have a completely different mechanism. They increase the amount of sugar excreted in the urine, thus lowering blood sugar levels. However, they may increase the risk of acidosis and have been known to cause vaginal thrush and increased urinary tract infections.
Gliflozins are, however, also used to treat renal disease and congestive heart failure. Some doctors may thus consider them if you have or have a high risk of these issues. They may also be associated with slight weight loss and reduced blood pressure.
Incretin mimetics, also known as GLP-1 agonists, are a relatively new group of injectable drugs that mimic the natural incretin hormones in your body that help lower post-meal blood sugar levels. They may be associated with transient nausea and vomiting. They have also been used for people wanting to lose weight.
Additionally, your doctor may recommend insulin therapy if the amount of insulin being produced by your pancreas is insufficient. This can happen after you have had type 2 diabetes for a while. Insulin resistance can lead your pancreas to produce excessive insulin, leading to pancreas damage.
Finally, people with type 2 diabetes may be prescribed other medication to lower the risk of complications. Since diabetes is often associated with high cholesterol, you may be given statins to lower your cholesterol levels. Your doctor may also give you low-dose aspirin to prevent blood clots or antihypertensives to lower your blood pressure. Some supplements can also potentially help control blood sugar.
This can lower the risk of complications even if you have issues controlling your blood sugar.
For people with prediabetes, the only treatment recommended is typically lifestyle changes to increase physical activity and reduce weight. People with prediabetes should have their blood sugar checked annually and self-monitor for symptoms that could indicate type 2 diabetes, such as an increase in the frequency of urination.
Gestational diabetes is typically treated similarly to type 2 diabetes, starting with the same lifestyle changes. Doctors now encourage healthy levels of moderate exercise during pregnancy unless there is a complication that results in risks.
Low-intensity exercise is ideal for those who were not active before pregnancy. If you were already active, talk to your doctor about which activities to continue and substitute.
It's a good idea to try and get your weight healthy before trying to get pregnant. You should not try to lose weight during pregnancy, and some weight gain is normal. However, being at a healthy risk reduces your risk of gestational diabetes and increases your chances of conceiving.
Typically, you will be given a healthy eating plan to help you and your baby get good nutrition and control your blood sugar.
Temporary insulin supplementation using shots is sometimes recommended. Insulin will not harm your baby. Metformin, in recent years, has gained acceptance as being safe in pregnancy, especially for those with polycystic ovary syndrome, but your obstetrician must guide the use of this medication.
Gestational diabetes typically goes away postpartum, but you should be screened for diabetes again a month or two after giving birth and should consider yourself at high risk for developing type 2 for the rest of your life. You should also make sure that your child eats a healthy diet and is physically active to reduce their risk of becoming obese or developing diabetes.