What is diabetes mellitus? More and more people in today’s world suffer from the metabolic disease diabetes mellitus, mostly known as diabetes. It is considered one of the major widespread diseases: In the United States, just over one in ten people have diabetes – that’s a hefty 34 million people. But what causes diabetes, and who is most likely to be affected?
Experts are particularly concerned about the rising number of people with type 2 diabetes. This is because diabetes increases the risk of various secondary diseases, including cardiovascular disease, kidney damage, and visual and nervous system disorders.
Type 2 diabetes is considered a disease caused by a combination of high-fat food, obesity, lack of exercise, and increasing life expectancy – these are supposedly the main reasons why diabetes is becoming increasingly widespread. The good news is that many of us are in control of some of these contributing factors and can therefore proactively reduce our risk of developing diabetes.
What causes diabetes, and what is the difference between type 1 and type 2 diabetes? Who is particularly at risk of developing the disease, and what are typical diabetes mellitus symptoms we should look out for? We explore the answers to these questions and commonly asked questions about how diabetes is diagnosed and what a diabetes diet should look like. Read on for more information!
What Is Diabetes Mellitus?
Diabetes mellitus, also known simply as “diabetes,” is a metabolic disease, whereby those affected permanently have too much sugar in their blood. This is what experts call “chronic hyperglycemia” (high blood sugar). People with diabetes have problems with their insulin production, in that this vital hormone can either no longer be produced or is not absorbed well enough by the body’s cells.
Why do our bodies need insulin? Insulin transports sugar from the blood into our body’s cells. These, in turn, use sugar as their main source of energy, enabling vital bodily functions such as movement, breathing, and brain and cardiac activity.
If we lack insulin or it no longer works effectively in the body’s cells, sugar accumulates in our blood. Long-term elevated blood sugar can cause damage, which is why the body tries to get rid of the excess sugar. Diabetics then excrete sugar through their urine, for example.
Did you know that the sugar in the urine of diabetics gives it a slightly sweet taste? This is where the technical term “mellitus” comes from: In Latin, it means “honeyed or sweet.”
What Are Typical Diabetes Mellitus Symptoms?
For those affected by diabetes mellitus, the lack of sugar in their cells becomes noticeable over time, as the body lacks the energy it needs in various places.
One of the better-known diabetes mellitus symptoms is diabetic foot syndrome. Years of elevated blood sugar levels can damage the nerves and blood flow in the foot. For this reason, many people with diabetes are more affected by injuries to their feet, and the wounds do not heal well on their own. Wounds can become very deep and large if they are not treated in time. In the worst case, the tissue can be so damaged by the wounds that toes or even the foot have to be amputated.
What Types of Diabetes Are There?
Experts distinguish between four different types of diabetes. Type 1 and 2 diabetes are the most well known, as they are much more common than the other two types of diabetes.
Type 3 diabetes is very rare. This form of metabolic disorder is triggered by genetic causes, pancreatic diseases, medication, or infection. Type 4 diabetes exclusively affects pregnant women; it is also called “gestational diabetes.”
Testing for gestational diabetes is an integral part of prenatal care. Doctors and medical staff can diagnose and treat the disease at an early stage. In most cases, this form of diabetes disappears after the birth of the child.
What Is Meant by Type 1 Diabetes?
Type 1 diabetes is an autoimmune disease, whereby the body destroys its own cells in the pancreas that are responsible for insulin production. As a result, those affected have little or no insulin. Sugar can no longer be transported from the bloodstream into the body’s cells, resulting in hyperglycemia.
For those affected by type 1 diabetes, symptoms usually appear suddenly. Typical symptoms include:
- Weight loss
- Fatigue and muscle weakness
- Poor wound healing
- Dry skin
- Vision problems
Diabetics excrete excess sugar in their urine. In the process, the sugar binds a lot of water, leading to a strong feeling of thirst and a greater urge to urinate.
You can find out more specific details about type 1 diabetes – including symptoms, diagnosis, and treatment – in our dedicated Health Portal article.
People with type 1 diabetes have to take insulin by injection, pen, or insulin pump. The body can then utilize this artificial insulin for sugar metabolism.
What Is Type 2 Diabetes?
To lower blood sugar levels, the pancreas initially produces more and more insulin. At some point, the effort of producing insulin becomes too great, and not enough can be produced. This is known as a “relative insulin deficiency,” whereby the pancreas produces insulin, but it is not enough for the body’s insulin-resistant cells. They are therefore still unable to absorb the sugar from the blood.
Type 2 diabetes develops subtly, in a way that means the disease often remains undetected for years. Symptoms are similar to those of type 1 diabetes:
- Fatigue, lack of drive, depressive moods
- Lack of concentration, forgetfulness
- Itchy, dry skin
- Poorly healing wounds
- Stronger feeling of thirst, increased urge to urinate
People with type 2 diabetes can optimize their health with a change in diet, sometimes in combination with tablets. The longer the disease lasts, the more likely it is that insulin deficiency will occur. If this does happen, those affected also have to inject themselves with insulin.
Which Is Worse: Type 1 or Type 2 Diabetes?
Although there are various differences between type 1 and type 2 diabetes, neither is better than the other, so to speak. Both forms cause serious secondary diseases if they are not treated. These include, for example, cardiovascular disease, stroke, eye and nerve damage, kidney problems, and diabetic foot syndrome.The goal with both forms of diabetes is therefore to detect the disease in good time and to optimally adjust blood glucose levels. In this way, secondary damage can be effectively prevented.
Table: Difference between Type 1 and Type 2 Diabetes
Type 1 Diabetes
Type 2 Diabetes
Reasons for onset
Proportion of all diabetes diseases
When the disease first emerges
Childhood to young adulthood
Lifelong insulin therapy
Change in lifestyle (diet change)
Who Is Most at Risk for Diabetes?
In most people, type 2 diabetes is associated with an unhealthy lifestyle and often does not occur until after the age of 40. Smoking, lack of exercise, and an unhealthy diet increase the risk of developing type 2 diabetes. Other factors include:
- Frequent family history of type 2 diabetes
- Obesity, high blood pressure, high cholesterol levels
- Gestational diabetes
- Medication that affects sugar metabolism (for example, cortisone)
- Other hormonal disorders (e.g. polycystic ovary syndrome)
Perhaps, for peace of mind, you’d like to monitor your cholesterol levels? These days, this can easily be done with a cholesterol test – either at your family doctor’s or with an at-home health test.
What Causes Diabetes: What Do We Know about Obesity?
Experts have observed a clear link between severe obesity and the development of type 2 diabetes. The reasons for this are being intensively researched.
Current studies suggest that the fatty tissue of overweight people releases inflammatory messenger substances that disrupt sugar metabolism. Insulin then apparently loses its effect, and blood glucose can no longer be absorbed by the body’s cells – leading to insulin resistance.
A healthy body weight, on the other hand, can positively influence the development and severity of type 2 diabetes.
Researchers are currently investigating through numerous studies how the risk and severity of diabetes are related to vitamin D deficiency. Sufficient vitamin D levels seem to improve insulin secretion. Whether taking vitamin D supplements can protect you from diabetes is not yet clear, as studies have recently come to contradictory conclusions.[15, 16]
What Is the Best Way to Diagnose Diabetes?
If you experience the typical diabetes mellitus symptoms mentioned above, you should be tested for diabetes. Various blood tests, a urine test, and, in some cases, an antibody test are possible methods of finding out whether you are diabetic.
You should take an antibody test if doctors suspect type 1 diabetes. Type 1 diabetics produce autoantibodies that attack the insulin-producing pancreatic cells. If the test does not detect these special antibodies in the blood, this form of diabetes can be ruled out.
What Blood Test Would Show Diabetes?
In a blood test, your doctor will take a blood sample to check whether your blood sugar level (glucose level) is elevated. Four different blood tests are available.
First, your casual blood glucose is usually measured. If blood glucose levels of 200 mg/dl (11.1 mmol/l) or more are detected in the laboratory, this indicates diabetes.
If your blood glucose level is high, the next step is to measure your blood glucose level when fasting – that is, after not eating any food for eight to twelve hours. This is the fasting blood glucose. Fasting blood glucose levels of 126 mg/dl (7.0 mmol/l) or more indicate diabetes.
What Is the Long-Term Blood Sugar Test?
The long-term blood glucose value, also known as your HbA1c value, provides information about your average blood glucose levels over the last two to three months. It measures the percentage of hemoglobin that is sugared. You have diabetes if your HbA1c is at 6.5 percent (48 mmol/mol) or more. You can take an HbA1c test performed by a doctor or purchase a self-test for home use.
Find out more about your HbA1c value and what it means more precisely in our article.
What Can an Oral Glucose Tolerance Test Tell Me?
In some cases, especially when type 2 diabetes is suspected, you might take an oral glucose tolerance test (OGTT). It indicates how well sugar from food can be absorbed into the body’s cells. If the OGTT-2-h value in the blood is 200 mg/dl (11.1mmol/l) or more, you can diagnose diabetes.[18, 19]
Can Diabetes Be Detected in a Urine Test?
A urine test can be used to determine whether your body is excreting higher amounts of sugar. To do this, special test strips are dipped into a urine sample, which make the sugar content of the urine visible by changing color. However, this method only detects diabetes at an advanced stage. With the test strips, elevated blood glucose levels are detectable only from 160 to 180 mg/dl (8.9 to 10 mmol/l).
Diabetes Diet: What Diet Is Best for Diabetes?
If you have diabetes, you can theoretically eat anything, as there is no special diet or foods you must avoid, as with a food allergy. However, diabetics must keep their blood glucose levels under control, and this is best achieved through a healthy and balanced diet. Of course, snacking is allowed.
Experts generally recommend a high-fiber diet with plenty of vegetables, whole grains, and legumes for people with and without diabetes. Lean meats, fish, and low-fat dairy products are suitable too. You should ideally opt for vegetable oils over other types of oil.
Dietary fiber is particularly great for diabetics because it allows blood sugar to rise slowly and steadily, so that the body is not overwhelmed. At the same time, recent studies show that a high-fiber diet (35 grams of fiber daily) has positive effects on body weight and cholesterol levels in diabetics. You can therefore effectively reduce your risk of cardiovascular disease, regardless of whether you suffer from type 1 or type 2 diabetes.
What Should Be on Your Plate?
With this plate method, you can create a healthy and varied meal for yourself over and over again. All you need to do is mentally divide your plate into four equal parts:
- Two parts with vegetables and/or fruit
- One part with protein-rich foods (meat, fish, eggs, legumes, dairy products – with as little oil as possible)
- One part with a side dish (potatoes, pasta, rice, grains – preferably whole grains and low-fat)
What Is Diabetes Mellitus – at a Glance
What Is Diabetes and What Types Are There?
Diabetes mellitus, also simply known as “diabetes,” is a metabolic disease, whereby affected individuals permanently have too much sugar in their blood. This is known as chronic hyperglycemia (high blood sugar).
People with diabetes have problems with the hormone insulin, which either can no longer be produced (type 1 diabetes) or is not absorbed as well by the body’s cells (type 2 diabetes).
Diabetes type 3 and type 4 are rare. Diabetes type 3 often runs in the family or is triggered by other diseases. Type 4 diabetes exclusively affects pregnant women and is also known as “gestational diabetes.”
What Are Typical Diabetes Mellitus Symptoms?
Typical diabetes mellitus symptoms are, for example, weight loss, fatigue and muscle weakness, poor concentration, poor wound healing, dry skin, visual impairment, a strong feeling of thirst, and an increased urge to urinate.
With type 1 diabetes, symptoms usually appear suddenly; with type 2 diabetes, they develop gradually.
How Do You Diagnose Diabetes?
Possible tests include various blood tests (measuring blood sugar), a urine test (measuring sugar content in the urine), and, in some cases, an antibody test (test for autoantibodies present with type 1 diabetes).
What Is the Ideal Diabetes Diet?
With diabetes mellitus, you can theoretically eat anything, because you don’t have to follow a special diet or avoid certain foods. That being said, with a healthy and balanced diet, you can keep your blood sugar level under control and reduce your risk of secondary diseases.
Experts generally recommend a high-fiber diet with plenty of vegetables, whole grains, and legumes. Lean meats, fish, and low-fat dairy products are also suitable. You should opt for vegetable oils.
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