The info here was inspired by a comment left by Jim. He said: “One of the things that has confused me since being diagnosed Type 2 is blood sugar and A1c.”
Of course, Jim is not alone. Many people are in the same boat, wondering, what on earth is the difference between hemoglobin a1c and blood sugar!
If that sounds like you, by the time you finish reading through the below info, it should all be crystal clear – no more confusions.
Blood Sugar Levels
When you take your fasting glucose (aka morning blood sugar levels) or measure 2 hours after a meal, you generally do it on a daily basis so you can get a mg/dL or mmol/l reading (depending where you live in the world).
Measuring daily levels is necessary because as Jim said: “When you’re in in the trenches like us, it seems to me focusing on the daily readings makes sense because we can affect those immediately (good or bad).”
And that’s exactly right. Even though your levels will change daily, they give you immediate feedback on your level of control.
Daily readings are influenced by diet, exercise, sleep, stress, lifestyle, medications and illness, which is why they can be up and down. Your goal is to hit daily averages that are within the normal range, majority of the time. That’s under 140 mg/dL or 7.8 mmol/L 2-hours after meals.
Diabetes Blood Sugar Level Goals
Note that ranges can vary slightly depending on what organization or healthcare provider you see. But generally your goals are to reach the following average numbers on a daily basis:
Time to Check | mg/dl | mmol/l |
Upon waking before breakfast (Fasting) | 70-130 (Ideal under 100) | 4-7.2 (Ideal under 5.6) |
Two hours after meals | Under 180 (Ideal is under 140) | Under 10 (Ideal is under 7.8) |
Bedtime | 90-150 | 5-8.3 |
What is Hemoglobin A1c?
This can sometimes be called A1c, HbA1c, or hemoglobin A1c.
A1c is another, more accurate way to measure blood glucose control.
The A1c is a blood test that reflects your average blood sugar levels over the past 3 month period.
Hemoglobin is our blood, and a process called glycosylation occurs where sugars (glucose) in your blood stream attach to hemoglobin (the protein in red blood cells that carries oxygen).
The average red blood cell lives for around 3 months, so when they do an A1c blood test they are testing ‘glycated hemoglobin’ (which essentially means glucose/sugar on the blood).
Unlike blood sugar which will give you a mg/dL or mmol/l measurement (depending where you live in the world), A1C gives a percentage (%) measurement.
The normal range is between 4-6%, so your goal is to lower your A1C so it’s a close to normal as possible.
What is the Difference Between A1c and Blood Sugar?
Blood sugar = daily readings that show more fluctuation because blood glucose levels are affected by diet, sleep, stress, exercise and so forth.
Hemoglobin A1c = an average reading of three months that is not influenced by the above daily factors.
The benefit of measuring A1c is that it gives a more objective view of your blood glucose control because it can’t be influenced by all those short term things like meal changes, infections, acute glucose changes etc.
Can You Convert A1c To Average Blood Sugar?
Remember, your HbA1c is a 3 month snapshot of how well your glucose levels have been running on average. Whereas your daily readings are an actual number of how much glucose is in your blood at any given time.
Therefore, you can’t get an exact match measurement for the two. However, there is an A1c to EAG calculator that estimates your average glucose based on A1c and vice versa.
Blood Sugar A1c Conversion Chart
Here is a chart of A1c to estimated average glucose (EAG).
A1c | EAG | |
% | mg/dl | mmol/l |
6 | 126 | 7.0 |
6.5 | 140 | 7.8 |
7 | 154 | 8.6 |
7.5 | 169 | 9.4 |
8 | 183 | 10.1 |
8.5 | 197 | 10.9 |
9 | 212 | 11.8 |
9.5 | 226 | 12.6 |
10 | 240 | 13.4 |
Just be aware, this is taking into consideration the average of all values, including both fasting and post-meal. Because the A1c is an overall 3 month average, it isn’t possible to give an exact correlation between the two because blood glucose is measured daily.
Still, the chart does work as a guide on how your blood sugar to a1c conversion might be tracking. Because sometimes if can be frustrating when you have to wait for that next blood test!
If you focus on gaining good control of your blood sugar levels, your A1C should follow suit, and likewise lower over time.
And just remember, it takes time to gain good control. We often hear people say: “I’ve been eating low carb for a week and my blood sugar is up one day and normal the next, what gives?”
The answer is: Give it time.
When testing blood glucose at home, it is normal for blood sugar to fluctuate, as it is influenced on a day-to-day basis by many things.
Just keep working at making changes to your nutrition and you will see your levels coming down quickly.
Be patient though. Just like A1c takes 3 months to reflect in your bloodstream, allow at least 3 months to see more normalized patterns in your levels occurring (or at least lower numbers if your numbers are currently running high).
Even then, once you see some good results occurring, you’ll still need to keep an eye on your levels going forward.
Eat well, exercise, sleep, stress less, and do what you can to gain/ maintain good control. It’s well worth the effort to stay in good health!
Please share this info to help others. Thanks!
Robert Ramsaywak
What does mg/dl and mmol/
What does it stand for
Milligram/???
Dr Jedha
Robert, those are the blood sugar measurements and we list two different ones because it depends where you live in the world. US is mg/dl, Canada, UK, Australia are mmol/l.
Gloria
This is great info, thank you. The other thing people need to know is that once you reverse the T-2, you are still on the diet for the rest of your life. Reversing T-2 means that what you are doing is working, but it must continue.
Gem
Great info very in lighting, I have a1c of 6.1 trying to Reverse this Pre-Diabetes , Changing my eating habits with walking exercise s 5 days a week for 45 minutes. My next A1c test is In May . Hope it’s lower to be off Meds.. what can I do to make my goal? CGS
Malorie: Dietitian (MS, RD, CLT)
Hi Gem, that is great you are changing your eating habits and exercising more. Both will help lower your A1c. I would really look at your eating habits and see where you may need to improve. You can start here to learn about using a low carbohydrate diet.
Holly Bifulk
I keep my daily carb count under 60 grams per day. You will see a huge difference and will loose weight at the same time.
Hope this helps.
Cecelia
This is a wonderful site. It has been so helpful to me. Please continue to promote this information, you are probably saving lives.
jim
I found this an important topic when I wrote those things you quoted. I have since been reminded that the number, whichever one it is, is really just a number. The glucose is great for immediate feed back which can be so important. This week I’m really struggling with eating correctly, doing a finger stick every morning and even taking my medications everyday. The blood glucose knows and tells me things just aren’t right. Hopefully, I get this back on track and by the time I have another A1C this detour won’t even be noticed. Thank you 3 month averaging! Now to work on not letting the “ONLY A NUMBER” thing not add to the stress and sleeplessness which are twisting my arm into putting wrong food to my mouth. Don’t you just hate doing the wrong thing and knowing it?
Jedha
It happens to us ALL Jim, even us nutritionists and dietitians who should know better! There are so many temptations around us all the time, and stress can promote cravings as well, so it’s human nature to slip up. And with diabetes, the routine of it all can get overwhelming sometimes. It’s just important to get back on track and not let it get out of hand into a much bigger downward spiral.
And yes, it’s really frustrating when you know you’re doing the “wrong” thing!
jim
Thank you Jedha! You are very kind. It helps knowing the experts are human too. Setting my personal rant aside I don’t want to lose track of what I really wanted to say. Blood glucose or A1C are just numbers and should be used as tools to help us keep track of our own journeys.
Jedha
Yes, great point!
Ashley Mann
Now it”s very clear now. Thank you. The convenience store is a sugar dealer. Therefore, fast food translates into a convenient slow death from the sugar high. Population control?
Catherine
Found this to be helpful