The worst thing you can do with prediabetes is sit still while eating processed food and refined carbohydrates. That combination spikes your blood sugar repeatedly, packs fat into your liver, and drives insulin resistance until your pancreas can’t keep up. About 5 to 10 percent of people with prediabetes progress to type 2 diabetes every year.
The ones who progress fastest share two habits: they don’t move much, and they eat in ways that hammer their blood sugar all day.
The good news? Prediabetes is reversible. The window is open. But you have to know what’s actually doing the damage before you can fix it.
What Can Make Prediabetes Worse?
Three things accelerate progression more than anything else: physical inactivity, a diet high in refined carbs and ultra-processed food, and fat accumulation in the liver.
Liver fat is the one most people miss. A 2025 meta-analysis of 59 cohort studies found that the Fatty Liver Index was the single strongest predictor of progression from prediabetes to type 2 diabetes, with an odds ratio of 6.14. That means people with high liver fat were more than six times more likely to develop diabetes.
Liver fat builds up when you eat more calories than you burn, especially from refined carbs and sugar. Your liver converts the excess into fat, and that fat directly worsens insulin resistance.
I’ve seen this with clients who thought they were doing everything right. One was eating what he called a “healthy diet” but drinking two to three glasses of juice a day and having white rice with most meals. His liver enzymes were elevated and his blood sugar kept creeping up. When we cut the liquid sugar and swapped in whole grains and vegetables, his numbers started moving in the right direction within eight weeks.
Physical inactivity compounds the problem. Muscle is your body’s main site for absorbing glucose. When you don’t use your muscles, they become less sensitive to insulin. Glucose that should go into muscle stays in your bloodstream instead.
Over time, your pancreas works harder and harder to compensate, until eventually it can’t.
Chronic poor sleep and high stress also push blood sugar up by elevating cortisol, a hormone that signals your body to release stored glucose. These aren’t minor contributors. They’re active accelerants.
Why Sitting Is More Dangerous Than Most People Think
Exercise is not optional with prediabetes. A 2024 network meta-analysis of 407 trials covering over 33,000 people found that exercise outperformed metformin on every major blood sugar marker in people with prediabetes. Exercise reduced HbA1c by 0.16 percent versus 0.10 percent for metformin. It reduced 2-hour glucose by 0.68 mmol/L versus virtually nothing for metformin. It cut insulin resistance scores by more than double what medication achieved.
Exercise beats the drug. That’s not a small finding.
The mechanism is direct. When your muscles contract during exercise, they absorb glucose without needing insulin to do it. Every session of movement is essentially a blood sugar flush. And over time, regular exercise rebuilds insulin sensitivity so your body handles glucose better even at rest.
High-intensity interval training showed particular benefits for glycemic control and cardiovascular risk factors in adults with prediabetes. You don’t need a gym membership or complicated equipment to do HIIT. Short bursts of effort followed by rest periods work. Twenty minutes, three to four times a week, can move the needle.
When I work with prediabetic clients in Port Melbourne, I don’t start them on complex programs. I start them walking briskly after dinner. That single habit after meals blunts the postprandial glucose spike better than most people expect. Then we build from there.
What’s the Fastest Way to Fix Prediabetes?
The fastest proven path combines exercise, diet change, and modest weight loss. Lose 5 to 7 percent of your body weight if you’re carrying excess, move for at least 150 minutes a week, and clean up your diet. That combination produces a 40 to 70 percent relative risk reduction in progression to diabetes.
For a 90kg person, 5 to 7 percent is 4.5 to 6.5kg. That’s achievable in two to three months with consistent effort. The weight loss matters because it directly reduces liver fat and visceral fat, which are the main drivers of insulin resistance.
The thing most articles get wrong here is telling people to focus on the long game only. Yes, long-term consistency matters. But early wins matter too because they change how you relate to the process.
One of my clients lost 4kg in six weeks by cutting ultra-processed snacks and adding three 30-minute walks per week. Her fasting glucose dropped from 6.4 to 5.8 mmol/L. She didn’t need supplements, a specific meal plan, or anything expensive. She needed two habit changes done consistently.
If your blood sugar is high enough that your doctor is considering medication, exercise is still your most powerful tool. Use both if needed, but don’t let a prescription make you feel like the lifestyle work is optional.
What Foods Can Prediabetics Eat Freely?
Non-starchy vegetables are the closest thing to a free food in prediabetes. Spinach, broccoli, cucumber, zucchini, capsicum, lettuce, cauliflower, green beans. These have minimal impact on blood sugar and are loaded with fiber, which slows glucose absorption.
Lean proteins are also safe and useful. Eggs, chicken breast, fish, tofu, Greek yogurt. Protein fills you up, has almost no effect on blood sugar, and preserves muscle mass during weight loss.
Legumes sit in a middle zone that leans positive. Lentils, chickpeas, and kidney beans have carbohydrates but also a lot of fiber and protein, so their actual effect on blood sugar is much gentler than their carb count suggests.
The foods to limit are refined carbohydrates and added sugars. White bread, white rice, pastries, soft drinks, fruit juice, flavored yogurt, most breakfast cereals. These cause sharp postprandial glucose spikes, and repeated spikes drive the progression from prediabetes to diabetes faster than almost anything else.
A 2021 randomized trial comparing a personalized glucose-targeting diet to a Mediterranean diet found that reducing individual glucose spikes produced significantly better outcomes than the Mediterranean approach alone. The Mediterranean diet is still very good. But the finding tells you that minimizing your personal glucose spikes matters, and that’s done primarily by reducing refined carbs and replacing them with whole foods.
What Is the Best Drink to Reverse Prediabetes?
Water is the best drink. That’s not a deflection. Replacing sugary drinks with water is one of the highest-use moves available to someone with prediabetes because liquid sugar bypasses many of the appetite signals that solid food triggers. You absorb it fast, your blood sugar jumps, and you don’t feel full afterward.
After water, unsweetened green tea has reasonable evidence behind it. It contains compounds called catechins that may improve insulin sensitivity. The effect size is modest but the drink itself is harmless and potentially useful.
Black coffee in moderate amounts is associated with lower diabetes risk in large observational studies, likely because of its polyphenol content. If you drink coffee, drink it without sugar and without flavored syrups.
Apple cider vinegar is popular in this space. There is some evidence it blunts postprandial glucose spikes when taken before meals, but the effect is small and it’s not a substitute for dietary change. Use it if you want, but don’t rely on it.
What to cut immediately: fruit juice, soft drinks, sports drinks, flavored milk, and energy drinks. One of my clients was drinking a bottle of orange juice every morning thinking it was healthy because it said “natural.” That single drink was adding 40+ grams of sugar to her breakfast. Cutting it dropped her fasting glucose by 0.4 mmol/L in three weeks.
The Hidden Risk Nobody Talks About: Complications Start Before Diabetes Does
Most people think complications like kidney damage, nerve problems, and eye changes only start once you have type 2 diabetes. The research says otherwise. Early signs of nephropathy, neuropathy, retinopathy, and cardiovascular disease have been documented in people with prediabetes.
This matters because it changes the urgency. Prediabetes isn’t a waiting room. It’s a state where damage is already beginning, slowly. Every month spent at elevated blood sugar is adding to that load.
A 2025 proteomic study of 108 people with prediabetes found that those who progressed to diabetes within one year had higher baseline levels of 14 specific proteins linked to reduced insulin sensitivity. Those proteins reflect the downstream effects of poor diet, inactivity, and metabolic stress. The biology is already shifting before the diagnosis changes.
Acting now isn’t about preventing a future problem. It’s about slowing a current one.
FAQ
Can prediabetes go away completely?
Yes. Research and clinical practice consistently show that prediabetes can reverse to normal blood sugar levels through lifestyle change. The Diabetes Prevention Program showed a 58 percent reduction in progression with diet and exercise. Many people reach normal HbA1c within months of consistent effort.
Is fruit bad for prediabetes?
Whole fruit in reasonable amounts is fine for most people with prediabetes. The fiber in whole fruit slows glucose absorption. Juice is not the same. Juice removes fiber and delivers sugar rapidly. Stick to whole fruit and watch portion sizes on high-sugar fruits like mango, grapes, and bananas.
How much exercise is actually needed?
150 minutes per week of moderate activity is the evidence-based target. That’s 30 minutes five days a week, or five 20-minute HIIT sessions, or any combination that gets you moving. Resistance training two to three times a week adds benefit on top of cardio because building muscle creates more glucose-absorbing tissue.
Does stress really affect blood sugar?
Yes, directly. Cortisol signals the liver to release stored glucose into the bloodstream. Chronic stress keeps cortisol elevated, which keeps blood sugar elevated. Sleep deprivation has the same effect. Managing stress and sleep is part of managing prediabetes, not a soft add-on.
Should I track my blood sugar at home?
It helps. Knowing how specific foods affect your personal glucose response lets you make smarter choices. A 2021 trial showed that targeting individual postprandial glucose spikes produced better outcomes than following a standard healthy diet alone. A basic glucometer is inexpensive and gives you real-time feedback that no generic meal plan can match.
What to Do Right Now
Cut refined carbs and liquid sugar today. That means white bread, white rice, sugary drinks, and fruit juice. Replace them with vegetables, legumes, whole grains, and lean protein.
Start moving after meals. A 10 to 15 minute walk after eating blunts blood sugar spikes better than waiting until the next morning to exercise.
Build up to 150 minutes of exercise per week. Include at least two resistance training sessions. If you want faster results, add HIIT two to three times a week.
If you’re in Port Melbourne and want structured support from a personal trainer who works with prediabetic clients, Fitness Network Port Melbourne offers coaching built around exactly this kind of metabolic health work. A good coach keeps you accountable and builds a program that matches where you are right now.
The biology is on your side if you act. Prediabetes responds to effort faster than most people expect. Start with the two biggest levers: cut the sugar and start moving. Build from there.
Sources
- Hu S, Ji W, Zhang Y, Zhu W, Sun H, Sun Y (2025) “Risk factors for progression to type 2 diabetes in prediabetes: a systematic review and meta-analysis” BMC public health. PMID: 40165126
- Zhao T, Yang Q, Feuerbacher JF, Yu B, Brinkmann C, Cheng S, et al. (2024) “Effects of exercise, metformin and their combination on glucose metabolism in individuals with abnormal glycaemic control: a systematic review and network meta-analysis” British journal of sports medicine. PMID: 39242178
- Barovic M, Hahn JJ, Heinrich A, Adhikari T, Schwarz P, Mirtschink P, et al. (2025) “Proteomic and Metabolomic Signatures in Prediabetes Progressing to Diabetes or Reversing to Normoglycemia Within 1 Year” Diabetes care. PMID: 39746149
- Li J, Yuan J, Wang F, Zeng Q, Zhang Y, Ma H (2026) “Effects of high-intensity interval training on glycemic control and cardiometabolic risk factors in adults with prediabetes: a systematic review and meta-analysis” Frontiers in Endocrinology. DOI: 10.3389/fendo.2026.1837386
- Milenkovic T, Bozhinovska N, Macut D, Bjekic-Macut J, Rahelic D, Velija Asimi Z, et al. (2021) “Mediterranean Diet and Type 2 Diabetes Mellitus: A Perpetual Inspiration for the Scientific World. A Review” Nutrients. PMID: 33920947
- Ben-Yacov O, Godneva A, Rein M, Shilo S, Kolobkov D, Koren N, et al. (2021) “Personalized Postprandial Glucose Response-Targeting Diet Versus Mediterranean Diet for Glycemic Control in Prediabetes” Diabetes care. PMID: 34301736
- Thipsawat S (2023) “Dietary Consumption on Glycemic Control Among Prediabetes: A Review of the Literature” SAGE Open Nursing. DOI: 10.1177/23779608231218189
- Tabák AG, Herder C, Rathmann W, Brunner EJ, Kivimäki M (2012) “Prediabetes: a high-risk state for diabetes development” Lancet (London, England). PMID: 22683128
