Getting lab results back is usually a stressful exercise in "is this bolded or not?" You scan the page, looking for flags. Then you see it. A hemoglobin A1c level 5.7 sitting right there on the line. It isn't a massive red alarm, but it’s the exact moment your doctor starts using the word "prediabetes."
It’s annoying. You feel fine. You might even eat better than most people you know. Yet, according to the American Diabetes Association (ADA), you have officially crossed the threshold from "normal" into a metabolic gray zone.
What does 5.7 actually mean for your blood?
Let’s get the science straight because there’s a lot of confusion about what this test even measures. People think it’s a snapshot of today's sugar. It’s not. It’s more of a three-month memory. Basically, sugar (glucose) in your bloodstream sticks to your red blood cells. Specifically, it sticks to the hemoglobin. Since red blood cells live for about 120 days, measuring the percentage of sugar-coated hemoglobin tells us your average blood sugar over the last few months.
At a hemoglobin A1c level 5.7, approximately 5.7% of your hemoglobin is glycated.
That might sound like a tiny amount. But in the world of endocrinology, it’s the definitive boundary. Anything below 5.7% is considered normal. At 5.7% to 6.4%, you are in the prediabetes range. If you hit 6.5%, that’s the diagnostic criteria for Type 2 diabetes.
It’s a tightrope.
The nuance of the "Normal" range
Context is everything. If you’ve been at a 6.2 and you’ve worked your tail off to get down to a hemoglobin A1c level 5.7, your doctor is probably doing a happy dance. You’re reversing the trend. But if you were a 5.2 last year and suddenly you’re here? That’s a signal that your body is starting to struggle with insulin resistance.
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Your pancreas is likely working overtime. It’s pumping out extra insulin to keep your blood sugar from spiking, but it’s losing the battle, just a little bit.
Some experts, like those at the Cleveland Clinic, point out that A1c isn't perfect. It can be skewed by things you wouldn't expect. Anemia, for instance. If you have iron deficiency, your red blood cells might live longer, which can artificially inflate your A1c. On the flip side, if you have sickle cell trait or certain types of hemolysis where blood cells die faster, your A1c might look better than it actually is.
The myth of "Only 5.7"
There’s this weird tendency to think "I’m barely prediabetic, so it doesn't count." That’s a dangerous game to play with your vasculature.
Even at a hemoglobin A1c level 5.7, your body is potentially sustaining subtle damage. Research published in The Lancet has shown that the "microvascular" complications we associate with full-blown diabetes—stuff like nerve damage in the feet or changes in the small vessels of the eyes—can actually start during the prediabetic phase.
It's not like a light switch that only turns on at 6.5. It's a dimmer switch.
The inflammation associated with elevated glucose starts early. It affects the endothelium, which is the inner lining of your blood vessels. When that lining gets irritated, it gets sticky. Plaque builds up easier. This is why people with prediabetes have a significantly higher risk of heart disease compared to those with an A1c under 5.0.
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Why did this happen to you?
It’s easy to blame the donuts. Honestly, it's rarely just the donuts.
Genetics plays a massive, often unfair role. Some people can eat processed carbs all day and stay at a 4.9. Others have a family history that makes their insulin receptors less "sticky" to glucose. Then there’s sleep. If you aren't sleeping, your cortisol is high. High cortisol tells your liver to dump glucose into your blood for energy you don't actually need because you're just sitting at a desk.
Muscle mass matters too. Your muscles are the primary "sink" for glucose. If you don't have much muscle, or if you aren't moving the muscle you have, that sugar has nowhere to go but to stay in the blood and stick to those red cells.
Making the 5.7 disappear
The good news? A hemoglobin A1c level 5.7 is incredibly reversible. You aren't "broken." You’re just getting an early warning.
You don't need a "diabetes diet." You need a metabolic reset.
The Order of Operations. This is a trick often discussed by biochemists like Jessie Inchauspé. If you eat fiber first (a salad or greens), then protein/fats, and save the starches for the end of the meal, you drastically flatten the glucose spike. Same calories. Different A1c result.
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The 10-Minute Walk Rule. This is non-negotiable. After your biggest meal of the day, walk for ten minutes. Just ten. This triggers your muscles to soak up the glucose that just hit your bloodstream from the meal, preventing it from lingering long enough to raise your A1c.
Weight loss is a lever, not the whole machine. You don't have to lose 50 pounds. Studies from the Diabetes Prevention Program (DPP) showed that losing just 5% to 7% of your body weight can reduce the risk of progressing to Type 2 diabetes by over 50%. For a 200-pound person, that’s only 10 to 14 pounds.
Watch the "Liquid Health." Stop drinking juice. Even green juice. If the fiber has been removed, it's just a sugar hit that your liver has to deal with instantly.
Strength Training. You don't need to be a bodybuilder. But adding even a small amount of muscle mass gives your body a larger storage tank for glucose.
The psychological hurdle
It’s easy to feel defeated. You might think your "good years" of eating whatever you want are over.
But look at a hemoglobin A1c level 5.7 as a gift of information. Most people don't find out they have a blood sugar issue until they're at a 7.0 and dealing with blurry vision or numb toes. You're catching it while the door is still wide open to change the outcome.
Check your magnesium levels too. There’s some evidence that magnesium deficiency can worsen insulin resistance. If your magnesium is low, your cells might not "unlock" for insulin as easily as they should.
Actionable Next Steps
- Request a Fasting Insulin test. A1c only tells you the average sugar, but it doesn't tell you how hard your pancreas is working. A "HOMA-IR" calculation (using fasting glucose and fasting insulin) can tell you if you're truly insulin resistant even if your A1c is still "low" in the prediabetes range.
- Get a Continuous Glucose Monitor (CGM) for two weeks. Even if you aren't diabetic, seeing how your body reacts to a piece of toast versus a bowl of oatmeal is eye-opening. Everyone’s microbiome reacts differently to carbs.
- Focus on Fiber. Aim for 30-35 grams a day. Fiber slows down the absorption of sugar, which is the easiest way to protect your hemoglobin from glycation.
- Re-test in 90 days. Don't bother re-testing in three weeks. Remember, those red blood cells need time to cycle out. Give your lifestyle changes a full three months to show up in the data.
Your hemoglobin A1c level 5.7 is a crossroads. One path leads to chronic disease management, and the other leads to metabolic flexibility. Choosing the latter usually just requires a few tweaks to your daily rhythm rather than a total life overhaul.