Prediabetes is reversible, and the most effective treatment is lifestyle change, not medication. A landmark study called the Diabetes Prevention Program found that losing roughly 4 kilograms (about 9 pounds) of body weight through diet and exercise reduced the risk of developing type 2 diabetes by 58%. In a five-year study tracking people with prediabetes who made sustained lifestyle changes, about 43% returned to completely normal blood sugar levels, 50% stayed in the prediabetes range without getting worse, and only 7% progressed to type 2 diabetes.
What Your Numbers Mean
Prediabetes is diagnosed when your blood sugar is higher than normal but not high enough to qualify as type 2 diabetes. Three tests can identify it: an A1C between 5.7% and 6.4%, a fasting blood glucose between 100 and 125 mg/dL, or a two-hour oral glucose tolerance test result between 140 and 199 mg/dL. Any one of these results is enough for a diagnosis.
Once you’ve been diagnosed, the CDC recommends repeating your A1C test every one to two years to track whether your blood sugar is improving, holding steady, or creeping toward the diabetes threshold. If you’re actively making changes, your doctor may test more frequently so you can see the results of your efforts sooner.
How Exercise Lowers Blood Sugar Directly
The single most impactful habit you can build is regular physical activity. The CDC recommends at least 150 minutes per week of moderate-intensity exercise, which works out to about 30 minutes five days a week. Walking briskly, cycling, swimming, or anything that raises your heart rate enough that you can talk but not sing comfortably counts.
What makes exercise so powerful for prediabetes is that it pulls sugar out of your bloodstream through a completely different pathway than insulin. When your muscles contract, they move glucose transporters to the surface of muscle cells, allowing sugar to flow in without needing insulin to open the door. This is significant because prediabetes is fundamentally a problem of insulin resistance, where your cells stop responding well to insulin’s signal. Exercise bypasses that broken signal entirely. The effect starts with your first workout and lasts for hours afterward, which is why consistent, frequent activity matters more than occasional intense sessions.
Adding strength training (resistance bands, bodyweight exercises, or weights) amplifies this effect by building more muscle tissue, which gives your body a larger reservoir for absorbing blood sugar around the clock.
What to Eat and Why It Works
You don’t need a special “prediabetes diet.” The core strategy is choosing foods that release sugar into your bloodstream slowly rather than all at once. A Mediterranean-style eating pattern built around whole grains, vegetables, legumes, nuts, olive oil, and fish consistently shows strong results for blood sugar control. Research comparing different versions of this diet found that meals built around slow-digesting carbohydrate sources like pasta, brown rice, rye bread, and seeds produced noticeably lower blood sugar spikes than meals with refined grains, even when the total amount of carbohydrates was the same.
Fiber is the key ingredient that slows digestion and flattens blood sugar curves. Research from Harvard Health found that people eating around 35 grams of fiber per day had lower blood sugar, lower cholesterol, less inflammation, and lower body weight compared to those eating only 19 grams. Most adults get about 15 grams daily, so closing that gap makes a measurable difference. Practical ways to get there include swapping white rice for brown, eating beans or lentils several times a week, snacking on nuts and vegetables instead of crackers, and choosing whole fruit over juice.
You don’t need to eliminate carbohydrates. The goal is choosing carbohydrates that come packaged with fiber and are minimally processed. A bowl of oatmeal with berries behaves very differently in your bloodstream than a bowl of sugary cereal, even if the calorie count is similar.
Why Weight Loss Has an Outsized Effect
The Diabetes Prevention Program found that every kilogram of weight lost (about 2.2 pounds) reduced the risk of progressing to diabetes by 16%. The participants who achieved the 58% risk reduction lost an average of about 9 pounds. That’s a meaningful but achievable target for most people, and it doesn’t require reaching an “ideal” body weight.
The reason modest weight loss works so well is that excess fat, particularly around the abdomen, actively interferes with insulin signaling. As visceral fat decreases, your cells become more responsive to insulin again, and your pancreas doesn’t have to work as hard to keep blood sugar in check. For many people, the combination of regular exercise and dietary changes produces this amount of weight loss naturally, without calorie counting or restrictive dieting.
Sleep and Stress Are Not Optional Factors
Sleep deprivation directly causes insulin resistance, even in otherwise healthy people. A study published in the journal Diabetes found that restricting sleep to five hours per night for just one week reduced insulin sensitivity by 11% to 20%. At the same time, afternoon and evening cortisol levels rose significantly. Cortisol is your body’s main stress hormone, and elevated levels trigger the liver to release more glucose into the bloodstream while simultaneously making cells less responsive to insulin.
This means you can eat well and exercise consistently but still struggle with blood sugar if you’re chronically sleeping fewer than six or seven hours. Prioritizing seven to eight hours of sleep per night is a genuine treatment strategy, not just general wellness advice. The same logic applies to chronic psychological stress, which keeps cortisol elevated through the same pathway. Regular physical activity helps on both fronts, improving sleep quality and lowering baseline stress hormones.
When Medication Enters the Picture
For most people with prediabetes, lifestyle changes alone are the first-line treatment. The American Diabetes Association has recommended considering metformin as an add-on to lifestyle changes since 2008, but only for specific groups: people with a BMI of 35 or higher, people under 60, or women with a history of gestational diabetes. Even in these groups, metformin is meant to supplement diet and exercise, not replace them.
Metformin works by reducing the amount of sugar your liver releases between meals and improving your cells’ sensitivity to insulin. It’s inexpensive and well-studied, but in the Diabetes Prevention Program, lifestyle changes outperformed metformin across nearly every demographic group. If your doctor suggests it, it’s typically because your risk factors are high enough that adding a second tool makes sense while you build sustainable habits.
Putting It All Together
The most effective approach combines several changes at once, but you don’t need to overhaul your life overnight. Starting with 150 minutes of weekly activity and shifting toward whole, fiber-rich foods will move your numbers. Adding consistent sleep of seven or more hours and gradual weight loss of even 5% to 7% of your body weight covers the interventions with the strongest evidence behind them. Track your progress with an A1C test every year or two, and expect changes to show up in your bloodwork within three to six months of consistent effort.
Prediabetes is one of the few conditions where the evidence overwhelmingly supports reversal. Nearly half of people who commit to sustained lifestyle changes return to normal blood sugar levels. The window to act is now, while your body can still recover full insulin function.