- Prediabetes can go three ways: progress to type 2 diabetes, stay the same, or return to normal.
- Without changes, about 5–10% of people progress each year, and up to 70% eventually develop diabetes.
- Many people do return to normal blood sugar, and doing so even once lowers long-term risk.
- Lifestyle changes delay or prevent diabetes for many years and protect the heart.
A prediabetes diagnosis often raises one big question: what happens next? The honest answer is that it depends. Prediabetes is a crossroads rather than a fixed destination. Large studies that have followed people for 10, 15 and even 30 years show that the path you take is shaped strongly by what you do in the first few years after diagnosis.
Three possible paths
Blood sugar keeps rising until it reaches the diabetes range. About 5–10% of people with prediabetes take this path each year.
Blood sugar stays in the prediabetes range for years. Risk remains, and the heart is still under some extra strain.
Blood sugar falls back into the normal range. This happens more often with weight loss, activity and in younger people.
A Cochrane review of more than 100 studies found that, over one to five years, a substantial share of people with prediabetes returned to normal blood sugar, while others progressed. The rates varied widely between studies, which tells us something important: the outcome is not fixed.
The long view: what the big studies show
In the Diabetes Prevention Program, lifestyle changes cut new cases of diabetes by 58% compared with usual care.
Follow-up showed people in the lifestyle group developed diabetes about 4 years later on average than the comparison group.
The lifestyle group still had 27% fewer cases of diabetes, long after the formal program ended.
In China’s Da Qing study, six years of lifestyle changes led to fewer heart attacks and strokes, fewer deaths from heart disease, and a longer life on average.
Knowler et al., NEJM 2002; DPP Research Group, Lancet 2009 and Lancet Diabetes Endocrinol 2015; Gong et al., Lancet Diabetes Endocrinol 2019.
What prediabetes does to the body over time
Even before diabetes develops, raised blood sugar and the insulin resistance behind it can affect the body. The risks are much smaller than with diabetes, but they are real, and they are one more reason to act early.
People with prediabetes have a modestly higher risk of heart disease, stroke and early death than those with normal blood sugar.
Early kidney changes, such as small amounts of protein in the urine, are more common.
Some people develop mild nerve damage, felt as tingling or burning in the feet.
Insulin resistance often goes hand in hand with fatty liver disease.
What tips the balance
- Gaining weight, especially around the waist
- Little physical activity and long sitting
- Sugary drinks and refined carbs
- Short sleep and chronic stress
- Smoking
- HbA1c toward the top of the range (6.0–6.4%)
- Losing 5–7% of body weight
- At least 150 minutes of brisk activity a week
- More fiber, vegetables, legumes and whole grains
- 7–8 hours of sleep
- Quitting smoking
- Starting early, soon after diagnosis
In the Diabetes Prevention Program, people who returned to normal blood sugar at least once during the study had a 56% lower risk of developing diabetes over the next several years than those who never did. That makes getting back to normal, even temporarily, a worthwhile goal.
Why some people progress faster
Two people with the same test result can follow very different paths. Progression tends to be faster when both fasting glucose and after-meal glucose are raised (rather than just one), when HbA1c is near the top of the range, and when there is a strong family history or a past pregnancy with gestational diabetes. Age matters too, but in an unexpected way: in the Diabetes Prevention Program, adults over 60 responded best of all to lifestyle changes, cutting their risk by 71%. It is never too late to benefit.
Keeping track
A simple follow-up plan
Keep your results in one place, such as a notebook or phone note. Seeing HbA1c move from 6.1% to 5.8% is powerful motivation, and a rising trend is an early signal to step up changes or discuss medicine with your doctor.
MythOnce you have prediabetes, diabetes is only a matter of time.
FactMany people never develop diabetes, and lifestyle changes delay it by years or prevent it altogether.
Common questions
How long does it take to go from prediabetes to diabetes?
It varies from a few years to decades, and for many people it never happens. Higher starting blood sugar, weight gain and inactivity speed it up.
If my blood sugar returns to normal, am I cured?
Your risk drops a lot, but the tendency remains. Keep the habits that got you there and continue yearly testing.
Should I take metformin to stop progression?
Metformin lowered diabetes risk by 31% in the Diabetes Prevention Program, less than lifestyle changes. Doctors may suggest it for people under 60 with a higher BMI, those with past gestational diabetes, or when blood sugar keeps rising despite changes.
Does prediabetes damage my eyes?
Serious eye damage is uncommon in prediabetes, but a small number of people show early changes. Regular eye checks are sensible, especially if you also have high blood pressure.
Already diagnosed with type 2 diabetes? Read When Your Type 2 Diabetes Changes in our 18-part Type 2 Diabetes Basics series.
- Prediabetes can progress, stay the same or return to normal.
- Without changes, 5–10% progress each year, but lifestyle changes cut that risk by more than half.
- Benefits last: fewer cases at 15 years and fewer heart attacks and deaths at 30 years.
- Test yearly and track the trend.
- Next: Treating prediabetes: the lifestyle changes that matter most.
Sources
- Richter B, Hemmingsen B, Metzendorf MI, Takwoingi Y. Development of type 2 diabetes mellitus in people with intermediate hyperglycaemia. Cochrane Database Syst Rev. 2018;10:CD012661.
- Knowler WC, Barrett-Connor E, Fowler SE, et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002;346(6):393–403.
- Diabetes Prevention Program Research Group. 10-year follow-up of diabetes incidence and weight loss in the Diabetes Prevention Program Outcomes Study. Lancet. 2009;374(9702):1677–1686.
- Diabetes Prevention Program Research Group. Long-term effects of lifestyle intervention or metformin on diabetes development and microvascular complications over 15-year follow-up. Lancet Diabetes Endocrinol. 2015;3(11):866–875.
- Gong Q, Zhang P, Wang J, et al. Morbidity and mortality after lifestyle intervention for people with impaired glucose tolerance: 30-year results of the Da Qing Diabetes Prevention Outcome Study. Lancet Diabetes Endocrinol. 2019;7(6):452–461.
- Perreault L, Pan Q, Mather KJ, et al. Effect of regression from prediabetes to normal glucose regulation on long-term reduction in diabetes risk. Lancet. 2012;379(9833):2243–2251.
- Cai X, Zhang Y, Li M, et al. Association between prediabetes and risk of all cause mortality and cardiovascular disease: updated meta-analysis. BMJ. 2020;370:m2297.
This article is for general education and is not a substitute for advice from your own doctor or healthcare team.