One important part of diabetes management is blood sugar readings. They can give a diabetic an idea of how well they are managing their condition and how much of an effect diet, medications, and/or insulin are having.
But, blood sugar readings can often be confusing. What is a good blood sugar reading, and what readings indicate that their diabetes needs to be better managed? Here’s how it breaks down.
Blood Sugar Ranges
There are three different blood sugar ranges that can be tested for. Each is done at a different time and a certain amount before or after eating. Those ranges are upon waking from a night’s sleep, before eating a meal, and from ninety minutes to two hours after eating. In some cases, you may have to do an overnight fast before getting a blood sugar reading or a series of blood sugar readings at a doctor’s office. [1]
Each range has three possible categories of scores: normal, prediabetic, and diabetic. Those scores are further discussed below.
Normal Range
Normal range scores vary for diabetic and nondiabetic individuals. For someone who doesn’t have diabetes, 4.0 to 5.9 mmol/L (72 to 125 mg/dl) before meals and under 7.8 mmol/L (140 mg/dl) after meals is considered a normal range of scores, although blood sugar can go as low as 2.8 mmol/L (50 mg/dl) before meals. [2] (Nondiabetics, since they make their own insulin and it is being used by the cells, don’t have to worry about blood sugar drops overnight except in rare circumstances.) [3]
For a diabetic, the normal ranges of blood sugar scores are 5 to 7 mmol/l (90 to 125 mg/dl) upon waking, 4 to 7mmol/l (72 to 125 mg/dl) before meals, and 8.5-9mmol/l (153 to 162 mg/dl) or under up to two hours after a meal. [4]Type 2 diabetics may not have to check their blood sugar upon waking. The higher score before meals is advised for type 2 diabetics, and the lower score before meals is advised for type 1 diabetics. This is reversed after meals – type 2 diabetics should have lower scores than type 1 diabetics.
Fasting blood sugar is considered normal if the score is below 3.9 mmol/L (71 mg/dl) and 5.6 mmol/L (100 mg/dl). [5]
Prediabetes Range
If a person has not been diagnosed with diabetes, they are considered prediabetic if their blood sugar is 5.55 mmol/l to 6.93 mmol/l (100 to 125 mg/dl) before meals and between 7.8 mmol/l to 11.0 mmol/l after meals. [6][7]
A person can also be considered prediabetic if they have a fasting blood sugar between 5.6 to 6.9 mmol/L (100 to 125 mg/dl) on at least two tests. [8]
Diabetes Range
Anyone who has not been diagnosed with diabetes is considered diabetic if they have a blood sugar of 7.0 mmol/l (125 mg/dl) or higher before meals and 11.1 mmol/l (200 mg/dl) after meals. [9] If a person has a fasting blood sugar score of 7.0 mmol/l or more on two different tests, they are also considered diabetic. [10]
Is 93/94/95/96/97 a Good Blood Sugar?
What is considered a good blood sugar reading depends on when it is being tested. Since there are three different occasions where blood sugar can be tested, and those times all have different normal levels, a reading at one time can be acceptable when it would not be acceptable at other times.
That being said, a score below 100 mg/dl is well within the normal range for both waking blood sugar levels and blood sugar levels right before eating when scores are expected to be the lowest. So, a score in those ranges can be considered a good blood sugar reading. [11]
Your doctor may have given you blood sugar readings that are lower than the ones considered acceptable above. If that’s the case, ask for an explanation.
What Affects My Blood Glucose Reading?
Many different things affect your blood glucose reading over time. Among them include: [12]
- The food you eat is an obvious source of your blood sugar levels, but it’s more than just the carbohydrates in the food. Both protein and fat affect blood glucose, although to a lesser degree than carbs.
- Drinking alcohol can cause blood sugar to rise, but it will later drop to a much lower reading, causing hypoglycemia.
- Exercise can cause blood sugar to drop over 48 hours. Short periods of intense exercise can also raise blood glucose. Not exercising can also have an effect – if you typically exercise every day and skip one day, your blood sugar may rise as a result.
- If you inject insulin, what you inject has a role in your blood glucose reading. Injecting into a place where you have less body fat can lead to hypoglycemia. [13] If you inject into an arm or thigh and later exercise that muscle, it can cause insulin to be used more quickly.
- Stress and illness can cause blood sugar levels to go up. [14]
- Some medications taken for other conditions can cause either high blood sugar or low blood sugar.
Tips for Keeping Blood Glucose Level from Spiking
The best way to manage blood glucose levels is to keep them on an even level. Some of the best ways to do so include:
- Your fasting blood sugar and blood sugar upon waking up should be 5.55 mmol/l or 100 mg/dl. If they are not around that number on a regular basis, try to figure out what is causing them to be high.
- Make whole grain complex carbohydrates part of your diet. The fiber in them will help you feel full longer, and the carbohydrates in them will be released more slowly over time.
- Start an exercise routine. Exercise can help lower blood sugar over time. (If you exercise on a daily basis and skip a day for whatever reason, you may have a temporary spike in blood sugar.)
- Both lack of sleep and stress can cause blood sugar spikes. Try to get eight hours of sleep a night and manage whatever sources of stress in your life exist. [15]
FAQ
Why are A1c Results Important?
A1C results are important because they can show your overall blood sugar levels over an extended period of time, two or three months. They can indicate whether your diabetes is consistently being managed over time.
What to do If My Glucose Level is Low?
If your glucose level is low and you are feeling faint or dizzy, take some fast-acting carbohydrates to raise it. Orange juice, a piece of hard candy, or glucose tablets or gels are good sources.
When should I call my doctor?
If your blood sugar levels seem to be too high or too low for your diet, or if they seem to fluctuate a lot between readings, it may be time to call your doctor.
Final Thoughts
Many of the complications caused by diabetes are caused by high blood sugar over time. Knowing what readings are acceptable over time, what causes high blood sugar and sudden spikes in blood sugar, and how to keep blood sugar from spiking are the most important tools in making sure those complications don’t occur.
References
- Diabetes UK. (2019, January 15). Normal and Diabetic Blood Sugar Level Ranges – Blood Sugar Levels for Diabetes. Diabetes.co.uk. https://www.diabetes.co.uk/diabetes_care/blood-sugar-level-ranges.html
- Diabetes UK. (2019, January 15). Normal and Diabetic Blood Sugar Level Ranges – Blood Sugar Levels for Diabetes. Diabetes.co.uk. https://www.diabetes.co.uk/diabetes_care/blood-sugar-level-ranges.html
- Reyhanoglu, G., & Rehman, A. (2020). Somogyi Phenomenon. PubMed; StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK551525/
- NHS Inform. (2019). Hyperglycaemia (high blood sugar) – Illnesses & conditions. Nhsinform.scot. https://www.nhsinform.scot/illnesses-and-conditions/blood-and-lymph/hyperglycaemia-high-blood-sugar
- Riley, L. (2022). Mean Fasting Blood Glucose. Www.who.int. https://www.who.int/data/gho/indicator-metadata-registry/imr-details/2380
- Diabetes UK. (2019, January 15). Normal and Diabetic Blood Sugar Level Ranges – Blood Sugar Levels for Diabetes. Diabetes.co.uk. https://www.diabetes.co.uk/diabetes_care/blood-sugar-level-ranges.html
- Centers for Disease Control and Prevention. (2019). Blood Sugar and Diabetes. CDC. https://www.cdc.gov/diabetes/managing/manage-blood-sugar.html
- Riley, L. (2022). Mean Fasting Blood Glucose. Www.who.int. https://www.who.int/data/gho/indicator-metadata-registry/imr-details/2380
- Diabetes UK. (2019, January 15). Normal and Diabetic Blood Sugar Level Ranges – Blood Sugar Levels for Diabetes. Diabetes.co.uk. https://www.diabetes.co.uk/diabetes_care/blood-sugar-level-ranges.html
- Riley, L. (2022). Mean Fasting Blood Glucose. Www.who.int. https://www.who.int/data/gho/indicator-metadata-registry/imr-details/2380
- Centers for Disease Control and Prevention. (2019). Diabetes Tests. Centers for Disease Control and Prevention. https://www.cdc.gov/diabetes/basics/getting-tested.html
- Editor. (2019, January 15). What Affects Blood Sugar Levels. Diabetes. https://www.diabetes.co.uk/blood-glucose/what-affects-blood-glucose-levels.html
- Editor. (2019, January 15). Insulin Injection Sites. Diabetes. https://www.diabetes.co.uk/insulin/injection-sites.html
- American DIabetes Association. (n.d.). Blood Sugar and Insulin at Work | ADA. Diabetes.org. https://diabetes.org/tools-support/diabetes-prevention/high-blood-sugar
- Alexander, H. (n.d.). 4 tips to avoid sugar spikes. MD Anderson Cancer Center. https://www.mdanderson.org/cancerwise/how-to-avoid-sugar-spikes.h00-159537378.html
