What is Blood Sugar? What are the Effects on the Body? – Blood Sugar Level
Blood glucose is glucose in the blood that is taken into the body with food, reaches the cells through the bloodstream and is used as an energy source. Foods are digested and enter the bloodstream as glucose. It is transported into cells and used by the hormone insulin. Glucose is the main source of energy for cells and the brain.
Carbohydrates are converted into blood glucose in the body. Excess glucose is stored in the liver for later use. Your body is designed to keep blood sugar levels stable. When blood sugar rises, the pancreas releases insulin to lower blood sugar levels to normal levels. Blood sugar is transported to provide energy to cells. A few hours after eating, blood sugar drops and the pancreas reduces insulin release. Liquid carbohydrate consumed on its own raises blood sugar faster than solid carbohydrate. Indigestible carbohydrates are dietary fiber and prevent the rapid rise of blood glucose. Therefore, including dietary fiber in your diet helps to maintain blood sugar balance
How is Blood Sugar Measured?
Test strips are used to measure blood glucose. The test strip is placed in the meter and a drop of blood is applied from the fingertip. In this way, blood glucose can be measured several times a day. It is an important procedure for daily blood glucose monitoring, especially for individuals with diabetes. In addition, blood glucose levels can be monitored with an electronic blood glucose monitor called a continuous tissue glucose meter (CGM) or flash glucose monitor.
An HbA1c blood test is done to measure the average blood glucose level in the body over the last three months. This value, also known as the A1c test, is a scale that indicates the risk of diabetes. A normal blood HbA1c value of 6.5% indicates diabetes. The target value for adults with diabetes may vary depending on the individual’s age, health status and medications. A high HbA1c indicates that there is too much sugar in the blood. This increases the likelihood of developing diabetic complications, especially related to your eyes and feet (3, 4).
What are Ideal Blood Sugar Values?
Although the ideal blood glucose level is individualized depending on the age and health status of the person, there are certain values that are ideal. These values vary between people with and without diabetes.
- The ideal fasting blood glucose level before a meal for a person without diabetes is 70-100 mg/dL. However, these values may be between 50-70 mg/dL or 70-110 mg/dL for some people.
- The ideal fasting blood glucose level for individuals with diabetes is 80-130 mg/dL. Postprandial blood glucose level after a meal is <180 mg/dL.
In individuals with diabetes, the fasting blood glucose target can be individualized according to the duration of diabetes, cardiovascular complications and other disease states (5, 6).
What is Fasting Blood Sugar? – Blood Sugar Level
Fasting blood glucose is the level of sugar in the blood in the fasting state before a meal. Fasting blood glucose is a common blood test used to screen and diagnose diabetes, prediabetes and gestational diabetes (gestational diabetes).
Prediabetes, Type 2 diabetes and gestational diabetes may not always be symptomatic and the person may not know it. Therefore, fasting blood glucose is monitored with regular examinations. Pregnant women and individuals with symptoms of diabetes should have fasting blood glucose measured. Fasting for 8-12 hours is required to prepare for a fasting blood glucose test.
- <100 mg/dL is the normal fasting blood sugar level for non-diabetic individuals.
- A fasting blood sugar level between 100-125 mg/dL indicates prediabetes. This range means that the blood sugar is higher than normal but not high enough to be classified as diabetes.
- >126 mg/dL is a high blood sugar level, which is a main indicator of diabetes.
Although fasting blood glucose values and classification have different values in different sources, values close to these levels are generally taken as basis (2, 7).
What is Postprandial Blood Sugar?
Postprandial blood glucose is the blood glucose value measured two hours after eating. The Oral Glucose Tolerance Test (OGTT) is a test that measures and evaluates postprandial blood glucose. The Oral Glucose Tolerance Test involves drinking a liquid with a high sugar content. Two hours later a blood test is taken. This enables the diagnosis of prediabetes, Type 2 diabetes and gestational diabetes. According to OGTT results, evaluations are made as follows:
- If the test result is <139 mg/dL, it indicates a normal blood sugar level.
- If the test result is between 140-199 mg/dL, it indicates prediabetes.
- A test result of ≥200 mg/dL signifies diabetes.
A blood test is extremely important for the diagnosis of diabetes in pregnant women. If blood glucose is elevated in two or three tests during OGTT, gestational diabetes is diagnosed (8).
What is Hyperglycaemia?
Hyperglycemia describes high blood sugar. It occurs in cases such as eating too much and sugar-heavy diet, stress, diabetes. A fasting blood glucose level >130 mg/dL indicates hyperglycemia.
When your blood sugar rises, your body gives the following symptoms:
- Frequent urination
- Constant thirst
- Constant hunger
- Dry mouth
- Blurred vision
If you have hyperglycemia, you should reconsider your medications and diet with the help of specialized healthcare professionals (9, 10).
What is Hypoglycaemia?
Hypoglycemia describes a drop in blood sugar below normal values. Drugs that lower blood sugar such as insulin, skipping meals, doing more physical activity than usual can cause hypoglycemia. When blood sugar in the body drops, the following symptoms occur:
- Heart palpitations
- Speech disturbances
- Blurred vision
Hypoglycemia can be more dangerous than hyperglycemia in some cases. When you feel low blood sugar, you can resort to short-term treatments such as fruit juice, sugar or glucose tablets (9).
What is Diabetes? – Blood Sugar Level
Diabetes is a disease that occurs when blood sugar levels are higher than normal. Sugar in the bloodstream is the main source of energy for cells. Digested food is broken down into glucose and enters the bloodstream. The hormone insulin released from the pancreas ensures that glucose in the blood is taken up by cells in different parts of the body. This allows blood sugar to enter the cells and be used. However, sometimes the body produces less insulin or the insulin is not used by the tissues. In this case, blood sugar cannot reach the cells and high blood sugar occurs.
There are three main types of diabetes:
- Type 1 diabetes occurs when the body does not produce enough insulin. The individual’s immune system sees cells that secrete insulin as foreign substances and attacks the pancreatic cells.
- In type 2 diabetes, insulin is produced in the body, but the cells do not respond to insulin. As a result, the pancreas secretes more insulin to help blood sugar enter the cells. This eventually damages the pancreas and leads to insulin resistance.
- Gestational diabetes occurs in women during pregnancy and often resolves after childbirth. However, women who have had gestational diabetes have a higher risk of developing type 2 diabetes in later years.
The risk of diabetes increases with age, overweight and a family history of diabetes. In addition, lack of physical activity, hypertension and malnutrition increase the risk of type 2 diabetes (11).