Several factors raise your risk of developing type 2 diabetes, and most people who get it have more than one working against them. The biggest drivers are excess weight, family history, age over 35, and belonging to certain racial or ethnic groups. Some of these you can change; others you can’t. Understanding where you fall helps you know whether screening or lifestyle changes should be on your radar.
Weight and Body Fat Distribution
Carrying extra weight is the single most significant modifiable risk factor for type 2 diabetes. Adults with a BMI of 25 or higher are considered overweight and face elevated risk. But the number on the scale tells only part of the story. Where your body stores fat matters too. Men with a waist circumference over 40 inches and women with a waist over 35 inches have a notably higher risk, because fat around the midsection is more tightly linked to insulin resistance than fat stored in the hips or thighs.
These thresholds aren’t universal. Asian Americans face increased risk at a lower BMI of 23 or higher, while Pacific Islanders reach the elevated-risk category at a BMI of 26 or higher. Research comparing diabetes incidence across ethnic groups found that South Asian adults develop type 2 diabetes at the same rate as white adults at BMIs roughly 5 to 6 points lower. For South Asian women, a BMI of about 23 carries the same diabetes risk as a BMI of 30 in a white woman. This means standard BMI charts can give a false sense of security if you’re of Asian or South Asian descent.
Family History and Genetics
Your genes play a substantial role. If one of your parents has type 2 diabetes, your lifetime risk of developing it is around 40%. If both parents have it, that figure climbs to nearly 70%. Having an affected parent or sibling roughly triples your risk compared to someone with no family history, and having two affected parents increases it about sixfold.
This doesn’t mean diabetes is inevitable if it runs in your family. Genetics loads the gun, but lifestyle factors largely determine whether and when it fires. Still, a strong family history is reason enough to get screened earlier and pay closer attention to weight and activity levels.
Race and Ethnicity
Type 2 diabetes does not affect all populations equally. Among U.S. adults (2021 to 2023 data from the American Diabetes Association), diagnosed diabetes rates break down as follows:
- American Indian or Alaska Native: 15.7%
- Black, non-Hispanic: 12.2%
- Hispanic: 11.8%
- Asian, non-Hispanic: 9.7%
- White, non-Hispanic: lower than all groups above
Within these broad categories, risk varies considerably. Among Hispanic adults, Puerto Rican individuals have the highest prevalence at 13.3%, while South Americans have the lowest at 5.0%. Among Asian Americans, Filipino adults have the highest rate at 12.2%, more than double the rate in Korean Americans (6.1%). These differences reflect a mix of genetic susceptibility, dietary patterns, body composition, and access to healthcare.
Age
Risk rises steadily with age, and data show a meaningful jump starting around 35. The U.S. Preventive Services Task Force now recommends that adults aged 35 to 70 who are overweight or have obesity get screened for prediabetes and type 2 diabetes, lowering the previous starting age from 40. That shift came after evidence showed diabetes incidence increases at 35 compared to younger ages.
Children and teens can develop type 2 diabetes too, particularly if they are overweight and have other risk factors like family history or belong to a higher-risk ethnic group. But the vast majority of new cases occur in adults over 35.
Prediabetes: The Clearest Warning Sign
Prediabetes means your blood sugar is higher than normal but not yet in the diabetic range. It’s defined by an A1C between 5.7% and 6.4% (normal is below 5.7%, and diabetes is diagnosed at 6.5% or above). About 5% to 10% of people with prediabetes progress to full type 2 diabetes each year. Over a 10-year period, roughly 12.5% make that transition.
The encouraging side of those numbers: within 10 years, 36% of people with prediabetes revert to normal blood sugar. Your odds of going one direction or the other depend heavily on where in the prediabetes range you fall. Those in the highest quarter of fasting blood sugar have a 16% chance of progressing over a decade and only a 13% chance of reverting to normal. The higher your A1C within the prediabetes range, the more urgently lifestyle changes matter.
Gestational Diabetes
Women who develop diabetes during pregnancy face a significantly elevated long-term risk. Between 50% and 70% of women with gestational diabetes will eventually develop type 2 diabetes, and about 30% of them will be diagnosed within just five years of giving birth. Having delivered a baby weighing 9 pounds or more is also an independent risk factor, even without a formal gestational diabetes diagnosis.
If you had gestational diabetes, regular blood sugar monitoring after pregnancy is essential. The postpartum period is a window where lifestyle interventions can delay or prevent progression.
Physical Inactivity
A sedentary lifestyle is one of the more modifiable risk factors. Whether the cause is a desk job, physical limitations, or simply low activity levels, sitting for long stretches reduces your muscles’ ability to use insulin effectively. Regular physical activity improves insulin sensitivity directly, independent of any weight you might lose in the process. Even modest increases in movement, like 150 minutes of brisk walking per week, can lower risk meaningfully.
Certain Medications
Some commonly prescribed medications can raise blood sugar or increase diabetes risk. The main categories include glucocorticoids (often prescribed for inflammation or autoimmune conditions), certain antipsychotic medications, statins (used for cholesterol), beta blockers, and thiazide diuretics (both used for blood pressure). This doesn’t mean you should stop taking a prescribed medication. But if you’re on one of these drug classes and already have other risk factors, it’s worth monitoring your blood sugar more closely.
How Multiple Risk Factors Stack Up
Most people who develop type 2 diabetes have several overlapping risk factors rather than a single overwhelming one. A 40-year-old Black woman with a BMI of 28, a parent with diabetes, and a history of gestational diabetes carries far more risk than any one of those factors alone would suggest. The combination matters.
If you recognize yourself in two or more of the categories above, screening with a simple blood test is the logical next step. Catching prediabetes early, when blood sugar is only mildly elevated, gives you the widest window to change course through diet, movement, and weight management before the condition progresses.