The most effective way to lower your A1c is to combine dietary changes, regular exercise, and weight loss rather than relying on any single strategy. Each of these can independently drop your A1c by roughly 0.4 to 0.6 percentage points, and together they can rival or exceed what first-line medication achieves on its own. Because your A1c reflects average blood sugar over the past 120 days (the lifespan of a red blood cell), it takes about three months of consistent changes before you see the full effect on your next lab result.
Know Your Target Number
A1c below 5.7% is considered normal. Between 5.7% and 6.4% falls in the prediabetes range, and 6.5% or higher indicates diabetes. If you already have diabetes, the American Diabetes Association recommends most adults aim for below 7.0%. Healthy older adults have a slightly relaxed target of below 7.5%, and those managing multiple chronic conditions may aim for below 8.0%. Your starting number matters because someone at 9% has more room to drop than someone at 7.2%, and the strategies that move the needle can differ at each level.
Shift What You Eat, Not Just How Much
Switching to lower-glycemic foods, those that raise blood sugar more slowly, lowers A1c by about 0.5 percentage points compared to a higher-glycemic diet. That’s a meaningful change from food choices alone. In practice, this means choosing steel-cut oats over instant, whole fruit over juice, beans and lentils over white rice, and whole grain bread over refined white bread. The principle is simple: foods with more fiber, protein, or fat slow down the conversion of carbohydrates into blood sugar.
You don’t need to eliminate carbohydrates entirely. The benefit comes from the type and quality of carbs, not from cutting them to zero. Pairing carbohydrates with protein or healthy fat at every meal (an apple with peanut butter instead of an apple alone) blunts the post-meal blood sugar spike that drives A1c upward over time.
Add Soluble Fiber Deliberately
Soluble fiber deserves special attention. A meta-analysis found that consuming roughly 13 grams of soluble fiber per day, about one tablespoon of a fiber supplement like psyllium husk, reduced A1c by about 0.58 percentage points in just eight weeks. That’s on par with some medications. You can get soluble fiber from oats, barley, beans, lentils, flaxseed, and certain fruits like oranges and apples. If your current intake is low, adding a daily serving of oatmeal plus a handful of beans at lunch can get you close to that 13-gram threshold without supplements.
Exercise: Pick What You’ll Actually Do
Both aerobic exercise (walking, cycling, swimming) and resistance training (weight lifting, resistance bands, bodyweight exercises) lower A1c by similar amounts. A large meta-analysis found resistance training alone reduced A1c by about 0.4 percentage points, and there was no statistically significant difference between resistance and aerobic training. The combination of both likely offers the greatest benefit, but the key finding is that you don’t have to run if you prefer to lift.
Most studies showing clear results used two to three sessions per week. Interestingly, the people who gained the most strength from their resistance training also saw the largest drops in A1c. This suggests that progressive challenge matters: if you’re lifting the same light weights month after month, the metabolic benefit plateaus. Gradually increasing your resistance or intensity keeps muscles adapting and pulling more glucose from your bloodstream.
If you’re starting from zero activity, even brisk walking for 20 to 30 minutes after meals can make a noticeable difference in post-meal blood sugar spikes, which is exactly what drives A1c up over time.
Lose Weight, Even Modestly
Weight loss is one of the most powerful levers for A1c reduction, and you don’t need to reach an “ideal” body weight to benefit. Research from the landmark DiRECT trial found that people who lost more than 22 pounds (about 10 kilograms) and kept it off for 12 to 24 months achieved high rates of type 2 diabetes remission, meaning their A1c dropped below the diabetes threshold without medication. Losing 5% of your body weight (roughly 10 pounds for someone who weighs 200) is the benchmark where clinically meaningful changes in blood sugar, blood pressure, and cholesterol typically appear.
How you lose the weight matters less than whether you sustain it. A study from the University of Colorado Anschutz campus compared intermittent fasting (eating normally four days a week and significantly restricting calories three days) with traditional daily calorie restriction. The intermittent fasting group showed more favorable changes in fasting glucose and A1c, and 58% of that group hit the 5% weight loss mark compared to 47% in the calorie-counting group. These were secondary findings that need larger trials to confirm, but they suggest that intermittent fasting may work better for some people simply because it’s easier to stick with.
Sleep Is a Blood Sugar Issue
Sleeping fewer than six hours a night raises fasting blood sugar and increases insulin resistance independently of weight. This isn’t a minor effect. Studies show that short sleepers have significantly higher rates of prediabetes and diabetes even after accounting for BMI and waist size. On the flip side, people who successfully extended their sleep beyond six hours showed measurable improvements in insulin resistance, insulin secretion, and the function of the cells in the pancreas that produce insulin.
If you’re doing everything right with diet and exercise but sleeping five hours a night, poor sleep may be quietly undermining your results. Aiming for seven to eight hours is one of the simpler changes that can support every other effort you’re making.
Track Your Blood Sugar in Real Time
Continuous glucose monitors (CGMs), small sensors worn on the arm or abdomen, give you a real-time view of how specific foods, activities, and even stress affect your blood sugar throughout the day. People who use CGMs consistently see notably better results: one study found that frequent CGM users reduced their A1c by 1.52 percentage points over 12 months, compared to 0.63 points in those who didn’t use a monitor at all.
The benefit isn’t the device itself. It’s the behavior change that comes from immediate feedback. When you can see your blood sugar spike 40 points after a bowl of cereal but only 15 points after eggs and toast, you start making different choices without needing willpower. CGMs are increasingly available without a prescription in some countries, though cost and insurance coverage vary widely.
How These Changes Compare to Medication
The most commonly prescribed first-line diabetes medication lowers A1c by up to 1.5 percentage points at its maximum dose. That’s a useful benchmark. A person who switches to a lower-glycemic diet (0.5 point reduction), adds daily soluble fiber (0.5 point), exercises three times a week (0.4 point), and loses a moderate amount of weight can potentially match or exceed that medication effect through lifestyle alone. For many people, the best results come from combining lifestyle changes with medication rather than choosing one or the other.
The timeline for seeing results on your next A1c test is roughly three months, since the test captures your average blood sugar over the lifespan of your red blood cells. If you make significant changes today, your next quarterly blood draw should reflect them. Some people see a dramatic drop of a full percentage point or more in that first three-month window, especially if they’re starting from a higher baseline and making multiple changes simultaneously.