Recognizing Type 2 Diabetes: Symptoms, Causes, and What Your Blood Sugar Tells You

What is blood sugar and what does insulin do?

Blood sugar, or glucose, is the main fuel for your cells. It comes primarily from carbohydrates in your diet and circulates through your blood to the rest of your body.

To get glucose from your blood into the cells, you need insulin, a hormone produced by your pancreas. Insulin acts like a kind of key: it opens the cell wall so that glucose can enter and does not remain stuck in your blood. In type 2 diabetes, your cells respond less and less well to insulin, a phenomenon called insulin resistance. Your pancreas initially tries to compensate for this by producing more insulin, but eventually this is no longer possible and your blood sugar increases structurally.

Symptoms of type 2 diabetes

The symptoms of type 2 diabetes develop gradually and are often vague in the beginning, which is why many people are diagnosed late. Common signs include:

• More thirst than normal and needing to urinate more frequently, as your body tries to eliminate excess sugar through urine
• Persistent fatigue, because your cells cannot properly use the glucose in your blood as energy
• Unintentional weight loss, especially with severely elevated blood sugar levels, because the body is less able to utilize glucose and therefore taps into more fat and muscle reserves.
• Blurred vision, due to fluctuations in the fluid balance of the eye lens when blood sugar is high
• Tingling or reduced sensation in the hands and feet, an early sign of nerve damage caused by prolonged high blood sugar levels
• Wounds that heal more slowly than normal, because high blood sugar affects blood circulation and the ability to heal
• More frequent infections, such as skin or bladder infections

You may experience some of these symptoms, or none at all. Precisely because the symptoms are so gradual and inconspicuous in themselves, type 2 diabetes is often only discovered by chance, for example during a general blood test.

Who is at risk of type 2 diabetes?

Type 2 diabetes is caused by a combination of heredity and lifestyle. A number of factors clearly increase the risk:

Being overweight, especially around the abdomen. Fat tissue around the abdominal organs makes cells more susceptible to insulin resistance.

Lack of physical activity. Muscles that are used infrequently absorb glucose less effectively, causing your blood sugar to rise more quickly.

Age. The risk increases as you get older, although more and more younger people are also being diagnosed.

Heredity. If you have parents, brothers, or sisters with type 2 diabetes, your own risk is clearly higher.

Past gestational diabetes. Women who had diabetes during pregnancy have an increased risk of developing type 2 diabetes later in life.

PCOS. Polycystic ovary syndrome is often associated with insulin resistance, regardless of body weight.

What can you do yourself?

• Exercise regularly. Both endurance training and strength training make cells more sensitive to insulin, allowing glucose to be absorbed more easily.
• Pay attention to your diet. Whole-grain products, vegetables, legumes, and sufficient fiber ensure a more gradual rise in your blood sugar than refined sugars and white grains. Maintain a healthy weight. Even a modest weight loss of five to ten percent can noticeably improve insulin sensitivity.
• Limit sugary drinks. These raise blood sugar quickly and provide little nutritional value.
• Stop smoking. Smoking increases the risk of insulin resistance and exacerbates the vascular damage that diabetes already entails.

Have your values ​​checked if you have risk factors. This is certainly worthwhile if you are overweight, have a family history, or have had gestational diabetes, even without symptoms. For most people, these lifestyle adjustments are the first step, and with an early diagnosis (prediabetes) they can delay or even prevent the onset of type 2 diabetes. If the diagnosis has already been made, a doctor can prescribe medication to keep blood sugar under control.

When is a blood test useful?

Because type 2 diabetes develops slowly, a blood test is the best way to detect it early, especially if you belong to a risk group. The marker glucose (fasting) measures your blood sugar level after at least eight hours of fasting and is the primary test used in the Netherlands to detect diabetes.

The marker HbA1c measures your average blood sugar over the past two to three months, rather than a snapshot. You do not need to be fasting for it, which makes it practical. HbA1c is primarily used to monitor blood sugar in people who have already been diagnosed with diabetes, but a value of 48 mmol/mol or higher can also independently confirm the diagnosis of diabetes, provided it is repeated with a second measurement.

In the event of an abnormal result, a doctor never makes the diagnosis based on a single measurement alone: ​​an elevated fasting glucose value is always repeated at a later time before the diagnosis of diabetes is definitively established.

What are normal blood sugar values?

For the fasting glucose value (after not eating for at least eight hours), Dutch general practitioners use these limits:

• Below 6.1 mmol/l: normal
• 6.1 to 6.9 mmol/l: increased risk, also known as impaired fasting glucose or prediabetes
• 7.0 mmol/l or higher: indicates diabetes, provided it is confirmed with a second measurement

For HbA1c, internationally Generally accepted: below 42 mmol/mol is normal, 42 to 47 mmol/mol indicates prediabetes, and 48 mmol/mol or higher indicates diabetes. In Dutch general practice, the emphasis for diagnosis lies primarily on the fasting glucose value; HbA1c is additionally used to monitor blood sugar over a longer period.

Prediabetes does not mean that you have diabetes, but rather that your body is already starting to struggle to regulate your blood sugar. This is often the moment when lifestyle adjustments make the biggest difference.

Conclusion

Type 2 diabetes usually develops slowly and initially causes vague or no symptoms at all, while your blood sugar can rise in the meantime. Being overweight, a lack of exercise, and heredity are the main risk factors, but lifestyle has a significant influence on whether and when the disease develops. Because early detection makes all the difference, blood tests for glucose and HbA1c are the best way to know where you stand, especially if you belong to a risk group. In the case of prediabetes, lifestyle adjustments can often still prevent it from developing into diabetes.