Prediabetes is reversible, and the most effective tools are ones you control: what you eat, how much you move, and how you sleep. A landmark prevention study found that people who lost 7% of their body weight and exercised 150 minutes per week cut their risk of developing type 2 diabetes by 58%. That’s a better result than medication alone. The key is starting early, because the sooner you act after a prediabetes diagnosis, the more likely your blood sugar will return to normal.
What Prediabetes Actually Means
Prediabetes means your blood sugar is elevated but hasn’t crossed into the diabetes range. It’s typically diagnosed with one of two tests: an A1C between 5.7% and 6.4%, or a fasting blood sugar between 100 and 125 mg/dL. Your body is still producing insulin, but your cells are becoming less responsive to it. Glucose lingers in the bloodstream longer than it should after meals.
This isn’t a permanent label. A study published in BMJ Open Diabetes Research & Care tracked people with prediabetes who made lifestyle changes and found that 43% reversed to normal blood sugar levels within about three and a half years. Another 50% stayed in the prediabetes range without progressing. Only 7% developed type 2 diabetes. The critical finding: people who started lifestyle changes within five years of their diagnosis saw significantly greater drops in blood sugar than those who waited longer.
The Foods That Move the Needle
The single most important dietary shift is replacing high-glycemic carbohydrates with low-glycemic ones. High-glycemic foods (white bread, white rice, sugary drinks, most breakfast cereals) cause a rapid spike in blood sugar followed by a crash. Low-glycemic foods release glucose slowly, keeping blood sugar steadier and putting less strain on your insulin response.
Low-glycemic foods include most fruits and vegetables, beans, lentils, minimally processed grains like steel-cut oats and quinoa, pasta cooked al dente, nuts, and low-fat dairy. You don’t need to memorize a glycemic index chart. A practical rule: the less processed the carbohydrate, the lower its glycemic impact. A whole apple is better than apple juice. Brown rice is better than white. A handful of almonds with lunch will slow down the glucose absorption from the rest of your meal.
Fiber deserves special attention. It slows digestion and blunts blood sugar spikes after eating. The Dietary Guidelines for Americans recommend 22 to 34 grams of fiber per day depending on age and sex, but most people get roughly half that. Adding a cup of black beans to a meal gives you about 15 grams. Other high-fiber options include lentils, raspberries, broccoli, chia seeds, and whole grain bread. Building fiber intake gradually helps avoid digestive discomfort.
Portion size matters as much as food choice. Even healthy carbohydrates will raise blood sugar if you eat large quantities at once. Spreading your carbohydrate intake across meals rather than loading up at dinner keeps glucose levels more stable throughout the day.
How Exercise Lowers Blood Sugar
Exercise works through a mechanism that’s independent of insulin. When your muscles contract, they pull glucose directly out of the bloodstream to use as fuel, bypassing the insulin signaling that’s become sluggish in prediabetes. Over time, regular exercise also increases the number of glucose transporters your muscle cells produce, making them permanently better at absorbing sugar from your blood. This is why consistent physical activity improves insulin sensitivity even on days you don’t work out.
The target is 150 minutes of moderate-intensity activity per week. Moderate intensity means you can carry on a conversation but couldn’t sing a song. You can break this up however fits your life: 30 minutes five days a week, 50 minutes three days, or 25 minutes six days. Walking counts. So do swimming, cycling, dancing, and yard work. The American Diabetes Association recommends exercising five to six days a week to maximize benefits, since the insulin-sensitizing effect of a single session fades after about 48 hours.
Adding resistance training (bodyweight exercises, resistance bands, or weight lifting) two to three times per week provides additional benefit. Muscle tissue is the largest consumer of blood glucose in your body, and building more of it gives you a bigger metabolic sink for sugar.
Weight Loss and How Much You Need
The Diabetes Prevention Program, the largest and most influential study on prediabetes, set a weight loss goal of 7% of body weight. For someone weighing 200 pounds, that’s 14 pounds. For someone at 170 pounds, it’s about 12 pounds. This is not a dramatic transformation. It’s a modest, achievable target that produced a 58% reduction in diabetes risk.
You don’t need to hit this number overnight. Losing one to two pounds per week through a combination of dietary changes and increased activity is sustainable and effective. The participants in the prevention program achieved their results through the same lifestyle changes described here: better food choices, more movement, and consistent follow-through. No extreme diets were involved.
Where you carry weight also matters. Fat stored around the abdomen is more metabolically active and contributes more to insulin resistance than fat stored in the hips or thighs. Even a small reduction in waist circumference can improve how your body handles glucose.
Sleep Changes Your Insulin Response
Sleep is an underappreciated factor in blood sugar management. Research published in The American Journal of Managed Care found that restricting sleep to 6.2 hours or less per night for six weeks increased insulin resistance by nearly 15%. Postmenopausal women experienced an even steeper rise of about 20%. The encouraging part: when participants returned to 7 to 9 hours of sleep per night, their insulin and glucose levels normalized.
Poor sleep also increases hunger hormones and cravings for high-carbohydrate foods, making dietary changes harder to maintain. If you’re doing everything right with food and exercise but sleeping poorly, you’re working against yourself. Consistent sleep and wake times, a cool dark room, and limiting screens before bed are straightforward changes that support blood sugar control.
When Medication Enters the Picture
For most people with prediabetes, lifestyle changes are the first and most effective treatment. But the 2025 ADA guidelines recommend considering metformin for a specific subset of people: those between ages 25 and 59 with a BMI over 35, a fasting blood sugar above 110 mg/dL, an A1C above 6%, or women who had gestational diabetes. If you fall into one of these categories, medication can work alongside lifestyle changes rather than replacing them. In clinical trials, lifestyle intervention consistently outperformed metformin alone.
Tracking Your Progress
After a prediabetes diagnosis, your doctor will typically recheck your A1C or fasting glucose at regular intervals, often annually. This gives you a concrete number to track over time. An A1C that drops from, say, 6.1% to 5.5% means your efforts are working and you’ve moved back into the normal range.
Between lab visits, paying attention to how you feel can also be informative. Many people with prediabetes notice they have more stable energy throughout the day once they reduce refined carbohydrates and increase activity. The afternoon crash after a high-carb lunch becomes less frequent. These aren’t diagnostic markers, but they’re real signals that your metabolism is responding to the changes you’re making.
The timeline varies. Some people see measurable improvement in three to six months. Others take a year or more. The research is clear that acting within the first few years of diagnosis gives you the best chance of full reversal, so the most important step is starting now rather than waiting for a perfect plan.