10 Facts You May Not Know About Hemoglobin A1C


I’d never heard of hemoglobin A1C until my husband, Mike, was diagnosed with Type 1 diabetes in 2002. At the time of his diagnosis, Mike’s A1C was 15.8%. The normal range of A1C is generally considered between 4-5.7%. (According to DiabetesMine, Dr. Francine Kaufman has seen an A1C as high as 22%.)

A hemoglobin A1C blood test reflects a person’s average blood sugar levels over the course of about three months. Hemoglobin is a protein in red blood cells that carries oxygen, and the A1C test measures how much sugar has “stuck” to those cells. The test is used both to diagnose and monitor Type 1 and Type 2 diabetes.

  1. A1C test goes by many other names, including glycated hemoglobin, glycosylated hemoglobin, hemoglobin A1C and HbA1c.
  2. The A in A1C stands for adult.
  3. In 2013, the FDA approved the first A1C test for diagnosing diabetes.
  4. In people without diabetes A1C values are higher in blacks, Asians, and Latinos when compared to white persons. Although the differences are small, they could have an impact on the use of a sole A1C value to diagnose diabetes in all ethnic populations.
  5. For most adults, the American Diabetes Association recommends a target A1C of below 7 percent. New and much debated guidance from the American College of Physicians, however, suggests that A1C should be between 7 and 8 percent for most adults with type 2 diabetes.

  6. Iron deficiency anemia is associated with a higher A1C. However, blood loss from surgery, heavy menstrual cycles, other types of anemia may cause an A1C to be falsely low.
  7. The A1C test doesn’t show sudden, temporary increases or decreases in blood glucose levels. “Even though A1C results represent a long-term average, blood glucose levels within the past 30 days have a greater effect on the A1C reading than those in previous months.”

  8. An A1C result is an average. It does not necessarily reflect time spent with in-range blood sugars. For example, a person’s A1C of 6% could be the average of many highs and lows, not simply the result of steady in-range blood sugar.
  9. There is no need to fast before an A1C test.
  10. It is possible to lower your A1C by making small lifestyle changes, like adding more exercise to your routine, or eating low carb meals and snacks. You can use this A1C calculator to estimate your A1C based on your blood sugar levels.
A1C levelEstimated average blood sugar level
5 percent97 mg/dL (5.4 mmol/L)
6 percent126 mg/dL (7 mmol/L)
7 percent154 mg/dL (8.5 mmol/L)
8 percent183 mg/dL (10.2 mmol/L)
9 percent212 mg/dL (11.8 mmol/L)
10 percent240 mg/dL (13.3 mmol/L)
11 percent269 mg/dL (14.9 mmol/L)
12 percent298 mg/dL (16.5 mmol/L)
13 percent326 mg/dL (18.1 mmol/L)
14 percent355 mg/dL (19.7 mmol/L)

*Source: Mayo Clinic

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3 years ago

my stepdaughter is a type 1 diabetic and has an A1C over 10 for over 10 years. Despite all our coaching, she doesn’t seem to care or doesn’t want to make the changes with her diet to bring this under control. What are your thoughts? how long will she be able to live without complications?

5 years ago

The article is informative but I would like to comment that the values recommended and “approved” by Medical Dingbats is way too high. Sugar glycation and the beginnings of damage to all our cells in our bodies start at 90 mg/dL which is in the normal range of 70-100 mg/dL. That should be the target. There’s a ton of research papers telling us that cutting unnecessary carbs is what lowers blood sugars and that should be the desired outcome. My A1c is now 4.7 which is approximately 88 mg/dL on a daily average or within the normal range. When I… Read more »

Richard B. Tucker
Richard B. Tucker
5 years ago
Reply to  Judith

Very well said Judith! You have found the Truth!!!

4 years ago
Reply to  Judith

I completely agree with you also. I am not in the medical profession, however, as a type II diabetic, it took the same life change for me. My A1C was over 7, I was on 2000 mg
Metformin a day. It was doing nothing. they put me on Janumet again my A1C was continuing to rise. A long story short two years later A!C 5.3 No pharmaceuticals at all for these last two years. Only diet exercise and some common vitamins, spices & minerals. Glucose 94, A1C 5.3

4 years ago
Reply to  Vic

Vic, maybe you could give more details on what you are doing for your diet and what supplements you are taking? Thanks in advance.

Ny Narine
Ny Narine
4 years ago
Reply to  Judith

…That was awesome. I love bread and flour products. However, I have to sacrifice to cut back my consumption, being just diagnosed at A1c 7.1. Dr. said I am diabetic. I asked her to give me another three months to lose some weight and cut back on carbs and do more walking & exercise.

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