Lowering your HbA1c is achievable through a combination of dietary changes, regular exercise, better sleep, and, when needed, medication. How much it drops and how quickly depends on where you’re starting. A normal A1c is below 5.7%, prediabetes falls between 5.7% and 6.4%, and diabetes is diagnosed at 6.5% or above. Most adults with diabetes aim for an A1c under 7%, though your personal target may differ based on age and overall health.
What Your A1c Actually Measures
Your A1c reflects your average blood sugar over the past two to three months. It works by measuring how much glucose has attached to hemoglobin, the protein in red blood cells that carries oxygen. This attachment happens naturally whenever glucose is circulating in your blood, but the more sugar present, the more hemoglobin gets “coated.” Since red blood cells live for about 90 to 120 days, the test captures a rolling average rather than a single snapshot.
This is why A1c doesn’t change overnight. A fasting blood sugar reading can swing from one morning to the next, but A1c moves slowly. That’s both the frustration and the advantage: it takes weeks of consistent effort to see a change, but once it drops, it reflects a real, sustained improvement in how your body handles sugar.
Cut Back on Refined Carbohydrates
Carbohydrates raise blood sugar more than protein or fat, so reducing them is the most direct dietary lever you have. A meta-analysis in Diabetes Research and Clinical Practice found that restricting carbohydrates to less than 26% of total daily calories lowered A1c by an average of 0.47% at three months and 0.36% at six months compared to higher-carb diets. That might sound modest, but for someone with an A1c of 7.5%, a half-point drop is clinically meaningful.
The catch: the same analysis found no significant difference at 12 or 24 months. This likely reflects how hard it is to maintain a very low-carb diet long term. A more practical approach for most people is to focus on the type of carbohydrates rather than eliminating them. Swap white bread, sugary drinks, and processed snacks for whole grains, legumes, and vegetables. These foods break down more slowly and produce smaller blood sugar spikes.
Fiber Deserves Special Attention
Fiber is technically a carbohydrate, but your body can’t digest it the way it digests starch or sugar. It slows the absorption of other carbohydrates you eat alongside it, which blunts the post-meal blood sugar spike. The federal Dietary Guidelines recommend 22 to 34 grams of fiber per day depending on age and sex, and most Americans fall well short of that. Good sources include beans, lentils, oats, berries, broccoli, and chia seeds. If your current intake is low, increase gradually to avoid digestive discomfort.
Exercise Consistently, Not Perfectly
Physical activity lowers blood sugar in two ways. During exercise, your muscles pull glucose out of the bloodstream for fuel. Over time, regular exercise also makes your cells more responsive to insulin, so they absorb sugar more efficiently even at rest.
A systematic review in BMJ Open Diabetes Research & Care compared resistance training (weight lifting, bands, bodyweight exercises) to aerobic exercise (walking, cycling, swimming) and found no significant difference in their effect on A1c. Both types work. The best choice is whichever one you’ll actually do four or five times a week. Combining both in a weekly routine is ideal, but consistency matters more than the specific format.
A brisk 30-minute walk after your largest meal can make an outsized difference because it catches blood sugar at its peak. If you’re starting from a sedentary baseline, even 10-minute walks after meals add up. The goal is to make movement a daily habit rather than an occasional event.
Prioritize Sleep
Sleep is an underrated factor in blood sugar control. Data from the National Health and Nutrition Examination Survey shows a U-shaped relationship between sleep and A1c: people who slept four hours or fewer per night had higher A1c levels than those sleeping seven to eight hours. Both the quantity and the quality of sleep mattered, with seven to eight hours of fair-to-good quality sleep associated with the best A1c levels.
The mechanism is straightforward. Poor sleep reduces your body’s sensitivity to insulin, meaning your cells need more of the hormone to clear the same amount of sugar from your blood. Over weeks and months, that adds up to higher average blood sugar and a higher A1c. If you’re doing everything right with diet and exercise but sleeping poorly, this could be the missing piece.
Manage Stress and Weight
Chronic stress triggers hormones like cortisol and adrenaline, which signal your liver to release stored glucose into the bloodstream. This was useful for outrunning predators, but in modern life it just means persistently elevated blood sugar. Stress management looks different for everyone: regular exercise covers part of it, but dedicated practices like deep breathing, meditation, or simply protecting downtime in your schedule can help keep stress hormones in check.
Losing even a modest amount of weight improves insulin sensitivity. For people who are overweight, losing 5% to 7% of body weight often produces a measurable drop in A1c. For a 200-pound person, that’s 10 to 14 pounds. You don’t need to reach an “ideal” weight to see benefits. The metabolic improvement from early weight loss is disproportionately large.
When Lifestyle Isn’t Enough
If your A1c remains above target after several months of sustained dietary and exercise changes, medication is a reasonable next step. The most commonly prescribed first-line drug lowers A1c by up to 1.5% at full doses, according to Johns Hopkins Diabetes Info. It works primarily by reducing the amount of sugar your liver releases between meals and by improving how your cells respond to insulin.
Medication works best alongside lifestyle changes, not as a replacement for them. The dietary and exercise strategies above continue to provide benefits on top of whatever a prescription achieves. Many people find that combining both approaches gets them comfortably under their target, while relying on either one alone falls short.
How Quickly You Can Expect Results
Because A1c reflects a two-to-three-month average, you won’t see a meaningful change on your next lab draw if it’s only a few weeks away. Most clinicians recheck A1c every three months when someone is actively working to lower it. A realistic expectation for aggressive lifestyle changes alone is a drop of 0.5% to 1.0% over three months. Adding medication can push that further.
The first three to six months of changes tend to produce the most dramatic improvements. After that, progress often slows as your body adapts and the easiest wins are behind you. This is normal and doesn’t mean your efforts have stopped working. Maintaining a lower A1c over years is what reduces the risk of complications affecting your eyes, kidneys, nerves, and heart. The goal isn’t a single good lab result. It’s building habits sustainable enough to keep that number down for the long haul.