The blood sugar concentration or blood glucose level is the amount of glucose (sugar) present in the blood of a human or an animal. The body naturally tightly regulates blood glucose levels (with the help of insulin that is secreted by pancreas) as a part of metabolic homeostasis.
If blood sugar levels are either increased or decreased by a greater margin than expected this might indicate a medical condition.
Diabetic patients must monitor their levels as body’s inability to properly utilize and / or produce insulin can pose a serious threat to their health.
What is blood sugar?
What is diabetes?
Levels and indication
How to lower blood sugar level?
Children blood sugar levels
Blood sugar levels chart
Checking for BS:
How to check blood sugar?
How to lower blood sugar level?
Can diabetes be cured?
Blood sugar level (or blood sugar concentration) is the amount of glucose (a source of energy) present in your blood at any given time.
A normal level for a healthy person is somewhere between 72 mg/dL (3.8 to 4 mmol/L) and 108 mg/dL (5.8 to 6 mmol/L). It, of course, depends on every individual alone. Blood sugar levels might fluctuate due to other reasons (such as exercise, stress and infection).
Typical levels in humans is around 72 mg/dL (or 4 mmol/L). After a meal the blood sugar level may increase temporarily up to 140 mg/dL (7.8 mmol/L). This is normal.
A blood sugar level between 72 mg/dL (4 mmol/L) and 108 mg/dL (6 mmol/L) is considered normal for a healthy adult.
Note: mg/dL and mmol/L are units of measure. mg/dL is mostly used in USA whereas mmol/L is mostly used in EU and other parts of the world. For easier conversion try our mg/dL mmol/L conversion tool.
For a healthy adult a normal level is between 72 mg/dL and 108 mg/dL (4 to 6 mmol/L). The concentration of glucose in the blood of a healthy person in the morning on an empty stomach is between 68 mg/dL and 108 mg/dL (3.8 and 6.0 mmol/L). Two hours after consuming foods or drinks rich in carbohydrates, the values are usually between 120 and 140 mg/dL (6.7 and 7.8 mmol/L).
For children up to 6 years of age desired level before eating is between 100 mg/dL (5.5 mmol/L) and 180 mg/dL (10 mmol/L). Before sleep values should be between 110 mg/dL (6.1 mmol/L) and 200 mg/dL (11.1 mmol/L).
For children between the age of 6 and 12, before eating, blood sugar levels should be between 90 mg/dL (5 mmol/L) and 180 mg/dL (10 mmol/L). Before sleep values should be between 100 mg/dL (5.5 mmol/L) and 180 mg/dL (10 mmol/L).
Children aged 13 to 19 should expect similar readings than those of adults.
Blood sugar levels rise and drop during the day. This is normal. However, dramatic fluctuations in your blood glucose levels may indicate problems.
Dramatic changes of blood sugar levels have significant physical symptoms and will increase your risk of diabetes-related complications.
Click on the image below to view a larger blood sugar levels chart.
Download your blood sugar levels log and keep track of your results – write down all of your measured values.
|Glucose mg/dL or mmol/L||Value|
|Before breakfast (fasting)||70 – 130 mg/dL or 3.9 – 7.2 mmol/L|
|Before lunch, supper and snack||70 – 130 mg/dL or 3.9 – 7.2 mmol/L|
|Two hours after meals||less than 180 mg/dL or less than 10mmol/L|
|Bedtime||90 – 150 mg/dL or 5 – 8.3 mmol/L|
|A1C (also called glycosylated hemoglobin A1c, HbA1c or glycohemoglobin A1c)||less than 7%|
Please note that you should perform several consecutive blood glucose tests and not rely on one single measurement.
The next chart displays all possible blood sugar (glucose) levels along with a short explanation of what the indicators are.
|Blood Sugar Levels||Indication|
|Less than 70 mg/dL (3.9 mmol/L)||Low fasting blood sugar|
|70 to 108 mg/dL (3.9 to 6 mmol/L)||Normal fasting blood sugar for adults|
|110 to 125 mg/dL (6.1 to 6.9 mmol/L)||Impaired fasting glucose (pre-diabetes)|
|126 mg/dL (7.0 mmol/L) and above in more than one test result||Diabetes|
|about 70 to 140 mg/dL (3.9 to 7.8 mmol/L)||Normal postprandial blood sugar|
|about 142 to 199 mg/dL (7.9 to 10.9 mmol/L)||Borderline postprandial blood sugar. May indicate pre-diabetes.|
|Less than 70 mg/dL (3.9 mmol/L)||Hypoglycemia (Initial Stage)|
|50 mg/dL (2.8 mmol/L)||Hypoglycemia (Fasting)|
|less than 50 mg/dL (2.8 mmol/L)||Insulin Shock|
|145 – 200 mg/dL (8 – 11 mmol/L) Post meal||Value suggesting early diabetes|
|More than 200 mg/dL (11 mmol/L) Post meal||Value suggesting established diabetes|
Normal values for blood sugar are (values are in mmol/L, mg/dL and HbA1c) in the table below.
|Blood sugar levels||HbA1c||mg/dL||mmol/L|
|low||less than 4||less than 65||less than 3.6|
When your blood sugar level drops below 70 mg/dL (3,9 mmol/L) this means you have a low level of blood sugar. The usual symptoms are:
- faltering speech,
- difficulty in concentration,
- visual disturbances…
Symptoms may vary – different people might experience different symptoms. In some cases symptoms can even remain unrecognized (unconscious hypoglycemia).
Chronically high blood sugar (diabetes) is caused by a number of abnormalities in the body, one of them being the affected vascular walls of small and large arteries (diabetic micro-and macro-angiopathy) in a process called atherosclerosis.
We can say that a blood sugar level is high if we measure glucose level and get the following values – more than 110 mg/dL (6.1 mmol/L) on an empty stomach or at any time more than 200 mg/dL (11.1 mmol/L).
High blood sugar levels affect the arteries throughout the body, especially the organs which have the richest blood circulation: heart, brain, kidney, senses, nerves and other organs.
If the high blood sugar is associated with disturbances in lipid metabolism (blood fat), the abnormalities are more intense. Diabetes is among the risk factors for major non-communicable diseases: cardiovascular (coronary) disease, cerebral vascular disease and peripheral vascular diseases.
Typical symptoms of high blood sugar levels (diabetes) are thirst, frequent urination and unexpected weight loss. Sometimes a patient may also experience the following:
- impaired vision,
- itching skin,
- increased appetite,
- skin infections,
- feeling of dizziness,
- heavy dehydration.
Type 1 diabetes symptoms are severe and last for a short time before the disease is diagnosed. Type 2 diabetes symptoms appear slowly and are usually unrecognizable or nearly absent.
Use this tool to convert blood sugar values.
There are basically two main tests which are conducted to determine whether someone has diabetes.
Impaired fasting glycemia test
When being tested for diabetes by a impaired fasting glycemia test, blood sugar levels will normally be taken after around eight hours of fasting.
Impaired glucose tolerance test
An impaired glucose tolerance test involves taking a concentrated amount of glucose and then measuring blood sugar levels after two hours.
In a healthy person, a normal blood glucose level is between 72 mg/dL (4 mmol/L) and 108 mg/dL (6 mmol/L). Read on how to check blood sugar values.
For checking your blood sugar level, you will need:
Medical alcohol to clean the skin where you will prick your finger, a sterile tool to prick your finger, some test strips and a glucose meter to read the test strip.
|Glucose mg/dL or mmol/L level||Value|
|less than 110 mg/dL or 6 mmol/L on an empty stomach||normal value|
|between 110 mg/dL or 6.1 mmol/L and 125 mg/dL or 6.9 mmol/L on an empty stomach||limit value|
|more than 125 mg/dL or 7.0 mmol/L on an empty stomach||possible diabetes|
|more than 198 mg/dL or 11.0 mmol/L anytime||possible diabetes|
At this time there is no known official case of cured diabetes, however with proper action (diet and exercise), type 2 diabetes can be suppressed, but never reverted. There is no known case of diabetes type 1 recovery. Gestational diabetes (high blood sugar levels that manifest during pregnancy) will revert after pregnancy, but might develop into Diabetes Type 2 later in life.
Why diabetes type 1 cannot be reversed
With Diabetes type 1 body’s cells that produce insulin are destroyed. These cells cannot be regrown or replaced. A person would need to use insulin injections to control their condition.
With type 2 diabetes your body does not use insulin properly (also known as insulin resistance). Over the time a patient’s condition worsens as body cannot make enough insulin to keep blood glucose at normal levels.
How to keep diabetes under control?
In addition to modifying your diet, walk for 10 minutes after each meal to help improve insulin sensitivity and glucose uptake into your cells. Eat quality food and monitor your carbohydrates. Get a referral to a certified diabetes educator who will modify their recommendations based on your body, not what the guidelines say. If your blood sugar is still high with the recommended amount of carbs per meal, decrease the carbs further. Avoid low fat foods. Fat and protein will help your body absorb carbs more slowly and prevent spikes and troughs in your blood sugar.
Since diabetic diet is restrictive, you should change your view from focusing on the things you can’t eat to focusing on all of the delicious things you can eat. All food groups are still on the table. You may have to modify recipes but there are so many awesome alternatives to almost any food available on the internet.
It is recommended to severely decrease your daily carbohydrates intake. However Low carb diets can still be rich and delicious.
Diabetics are recommended to avoid certain types of fruit, however, in moderation, all kinds of fruits can still be consumed. They key is to eat them in moderation. For example, half a banana is already one serving of carbohydrates. Apples and oranges should be no larger than a tennis ball. Be careful with dried fruits because they are concentrated.
List of foods that raise blood sugar levels
High Glycemic index foods
Certain foods will make your blood sugar go up quite rapidly. These foods are known as s high-glycemic foods. See more on glycemic index.
Avoid eating foods that are high on the glycemic index (bananas, pineapple, watermelon and dried fruits, carrots, white potatoes and beets, and corn – this means high fructose corn syrup, so virtually all packaged foods). Eat fresh fruit with skins at the beginning of your meal (not as dessert). At least one meal a day, preferably dinner, avoid grains (potatoes, rice, wheat (bread)) and avoid sugar, especially artificial sugars.
It is recommended to have several meals per day. Having multiple meals per day will help diabetics in maintaining optimal glucose blood levels. Since every meal will affect blood glucose levels it is best to break diet down into lighter meals, which in turn means easier regulation of blood glucose. In diabetes, the pancreas either does not produce enough insulin or it produces enough but it is unable to utilize it efficiently.
There are, of course, other factors that influence blood glucose rise and fall that should be taken into account (such as exercise, stress and infection), meaning that a rise in blood glucose it not always due to ingestion of food.
A patient with diabetes is at a 5 times greater risk of developing cardiovascular disease than patient without diabetes. One third of all cardiovascular diseases also affect people with diabetes.
Three quarters of diabetics die from cardiovascular disease. Women with diabetes have a 4 times greater risk of death from cardiovascular disease. People suffering from diabetes usually have high cholesterol levels as well.
Disturbances in the metabolism of blood sugar levels are mainly the consequence of heredity (diabetes in the family), age (over 40), poor diet, excessive body weight (obesity) and physical inactivity. Disturbances in the metabolism of blood sugar were present in 20% of adult Europeans during 2002-2005 a study showed.
RECOMMENDATIONS to decrease elevated blood sugar:
Blood sugar level is determined in the fasting state. In a healthy person, a normal blood glucose level is less than 108 mg/dL or 6 mmol/L on an empty stomach.
Possible values are
- normal blood sugar level (the blood glucose level is normal on an empty stomach),
- disruption of glycemia (blood glucose in the blood on an empty stomach is increased to a maximum value between 110 and 124 mg/dL (6.1 and 6.9 mmol/L),
- diabetes (elevated blood sugar levels to 126 mg/dL / 7.0 mmol/L or more).
What can you do to lower the chance of developing diabetes:
- lose weight – be fit,
- sleep more, be rested.
- have a healthy diet (read how should a diabetic diet look like) with as many vegetables and fruits, a lot of fiber, consume less calories, less fat, less alcoholic beverages and no simple sugars,
- workout at least 30 minutes per day.
Useful resource: blood sugar levels chart:
American Diabetes Association (ADA) – http://www.diabetes.org/
Children with Diabetes – http://www.childrenwithdiabetes.com/
National Heart, Lung, and Blood Institute – http://www.nhlbi.nih.gov/
International Diabetes Federation – http://www.idf.org/
CDC on Diabetes – http://www.cdc.gov/diabetes/
American Association of Diabetes Educators – http://www.diabeteseducator.org/