Lowering your blood glucose and A1c comes down to a handful of lifestyle changes that work together: adjusting what and how much you eat, moving more, sleeping better, and staying hydrated. A normal A1c is below 5.7%, prediabetes falls between 5.7% and 6.4%, and diabetes is diagnosed at 6.5% or higher. Even modest changes in daily habits can shift these numbers meaningfully within a few months.
How A1c and Daily Glucose Are Connected
Your A1c reflects your average blood sugar over roughly the past two to three months. It’s not a snapshot of one morning; it captures how well your body has been managing glucose day after day. That means a single good week won’t move it much, but consistent changes over 8 to 12 weeks will. Everything below targets both your daily glucose readings and your A1c together, because the same strategies improve both.
Cut Back on Refined Carbohydrates
Carbohydrates have the most direct effect on blood sugar. When you eat bread, rice, pasta, sugary drinks, or sweets, your body converts them into glucose quickly, and your blood sugar rises. Reducing your total carbohydrate intake is the single most powerful dietary lever for lowering A1c.
In a community-based study published in BMJ Open Diabetes Research & Care, people with type 2 diabetes who followed a low-carbohydrate diet (keeping net carbs to about 20 grams per day or 5% to 10% of total calories) lowered their A1c by an average of 1.29 percentage points compared to a usual-care group. That’s a clinically significant drop, often comparable to what a first-line medication achieves. Multiple studies of similar low-carb approaches have found A1c reductions greater than 1% over periods ranging from 12 weeks to one year.
You don’t necessarily need to go that low to see results. Replacing refined grains and added sugars with vegetables, nuts, legumes, and whole foods will reduce your carb load and slow glucose absorption. The key is consistency over weeks and months, not perfection at every meal.
Add More Soluble Fiber
Soluble fiber slows the rate at which sugar enters your bloodstream after a meal. It forms a gel-like substance in your digestive tract that delays carbohydrate absorption and helps smooth out glucose spikes. Good sources include oats, beans, lentils, barley, flaxseeds, and fruits like apples and citrus.
A meta-analysis of randomized controlled trials found that a daily intake of roughly 7.6 to 8.3 grams of soluble fiber improved blood sugar control in adults with type 2 diabetes. To put that in practical terms, a cup of cooked oatmeal has about 2 grams of soluble fiber, a cup of black beans has around 4 grams, and a medium apple has about 1 gram. Combining a few of these foods throughout the day gets you into that effective range without supplements.
Exercise Regularly, Any Type
Physical activity lowers blood sugar in two ways: your muscles pull glucose out of the bloodstream for energy during the workout, and over time, exercise makes your cells more responsive to insulin. Both aerobic exercise (walking, cycling, swimming) and resistance training (weights, bands, bodyweight exercises) are effective.
A systematic review found that resistance training alone reduced A1c by an average of 0.39 percentage points compared to inactive controls. When researchers compared resistance training head-to-head with aerobic training, there was no statistically significant difference between the two. In other words, the best exercise for lowering A1c is whichever type you’ll actually do consistently. Combining both types in a weekly routine is ideal, but if you’re starting from zero, pick one and build the habit first.
For immediate glucose management, timing matters. Blood sugar typically peaks within 90 minutes of eating. A short walk after a meal, even 10 to 15 minutes, can blunt that post-meal spike by helping your muscles absorb glucose right when it’s flooding your bloodstream. This is one of the simplest, most accessible tools available.
Lose a Moderate Amount of Weight
You don’t need to reach an “ideal” body weight to see your numbers improve. The Diabetes Prevention Program, one of the largest and most influential studies on preventing type 2 diabetes, set a goal of just 5% to 7% body weight loss over six months. For someone weighing 200 pounds, that’s 10 to 14 pounds. Participants who hit that target through diet and exercise significantly reduced their risk of developing diabetes, and meta-analyses involving thousands of patients have confirmed that structured programs combining exercise and dietary changes for at least 12 weeks produce statistically significant A1c reductions.
The weight loss itself helps because excess fat, particularly around the midsection, makes your cells less sensitive to insulin. As fat decreases, insulin works more efficiently, and less glucose lingers in your blood.
Prioritize Sleep
Poor sleep raises blood sugar through several overlapping mechanisms. When you’re sleep-deprived, your body ramps up cortisol production, which signals the liver to release more glucose into the bloodstream. At the same time, your sympathetic nervous system (the “fight or flight” system) becomes more active, raising levels of stress hormones like noradrenaline that promote fat breakdown and increase circulating fatty acids. Those excess fatty acids interfere with insulin signaling in the liver and muscles, making it harder for your cells to absorb glucose.
Sleep deprivation also promotes fat accumulation in the liver, which further worsens insulin resistance. The net effect is that consistently sleeping fewer than six or seven hours a night can raise your fasting glucose and, over time, your A1c, even if your diet and exercise habits are solid. Aiming for seven to eight hours of sleep per night removes one of the hidden drivers of high blood sugar.
Stay Well Hydrated
Dehydration has a direct and somewhat surprising effect on blood sugar. When your body is low on water, it releases a hormone called vasopressin that tells your kidneys to conserve fluid. That same hormone also raises blood glucose levels. Research on people with type 2 diabetes found that just three days of reduced water intake significantly worsened blood sugar response during glucose testing, with the effect mediated partly through increased cortisol.
In the study, blood glucose at the two-hour mark was meaningfully higher in the dehydrated group (21.0 vs. 19.1 mmol/L) compared to those who were well hydrated. Drinking enough water throughout the day, roughly 8 to 10 cups for most adults, is a low-effort habit that supports everything else you’re doing.
What About Supplements?
Berberine, a compound found in several plants, is one of the most commonly discussed supplements for blood sugar. While some studies suggest it can modestly improve glucose levels, head-to-head research has found that metformin (the most widely prescribed diabetes medication) is more effective for blood sugar control. Berberine may offer some benefits for cholesterol, but it’s not a reliable substitute for proven lifestyle changes or prescribed medication.
No supplement replaces the fundamentals. If your A1c is in the prediabetes or diabetes range, the strategies with the strongest and most consistent evidence are dietary carbohydrate reduction, regular physical activity, moderate weight loss, adequate sleep, and proper hydration. These work through different pathways, and their effects stack. Combining even two or three of them can produce the kind of sustained A1c drop that changes your health trajectory.