· Lee Chee Cheow, M.Sc. Dip CMP · Metabolic Health · 4 min read
Type 2 Diabetes Risk Factors You Can (and Can't) Control
Some diabetes risk factors are fixed the day you're born. Others move with every meal, every night's sleep, and every waistline change. Here's how much each one actually matters, in numbers.
Type 2 diabetes doesn’t have a single cause — it’s the result of several risk factors stacking on top of each other, some fixed and some negotiable. Knowing which is which matters, because it changes where it’s worth putting your effort. Two factors you were born with can raise your risk several-fold; several everyday habits can push it up or down by similar margins.
Here’s what the research actually shows about each one.
The two you can’t change
Age
Risk doesn’t rise in a straight line with age — it accelerates. After age 45, the relative risk of developing type 2 diabetes increases by roughly 1.5 to 2 times with each additional decade. Singapore’s own numbers illustrate this clearly: the National Population Health Survey 2024 found diabetes prevalence of just 2% among 30-39 year-olds, rising to 5% at 40-49, 13% at 50-59, and 22% at both 60-69 and 70-74 — an elevenfold jump between the youngest and oldest brackets measured. Men consistently show higher rates than women at every age band (for example, roughly 25.5% of men aged 60-69 versus 18.5% of women).
Family history
Having a first-degree relative — a parent or sibling — with type 2 diabetes raises your own risk by 2 to 6 times. This isn’t just genetics; researchers note that family history “might indicate shared genotypes, environments, and/or behaviours,” meaning the household you grew up in matters as much as the DNA you share.
The scale of this effect shows up clearly in the Joint Asia Diabetes Evaluation (JADE) Register, which looked at family history prevalence among 86,931 people with type 2 diabetes across 11 Asian countries. Overall, 59.5% had a family history of the condition, but the rate varied enormously by country — from 39.1% in Vietnam to 85.3% in Malaysia. Singapore sat near the high end at 71.5%, meaning roughly seven in ten Singaporean patients with type 2 diabetes had a first-degree relative who also had it.
The risk factors within your control
A 2025 systematic review and meta-analysis in BMC Public Health quantified how much a range of everyday factors shift the odds of progressing from prediabetes to full type 2 diabetes. The results split cleanly into three groups.
Psychosocial factors turned out to carry some of the largest odds ratios in the entire dataset:
| Factor | Odds ratio |
|---|---|
| Anxiety | 2.61 |
| Depression | 1.88 |
| Insufficient sleep | 1.36 |
| Social deprivation | 1.15 |
An odds ratio of 2.61 for anxiety means the psychological side of health is not a side issue here — it’s one of the strongest modifiable risk factors identified.
Lifestyle factors were more modest but still measurable: smoking carried an odds ratio of 1.31, and drinking 1.07.
Obesity-related measures were also significant, and interestingly, the shape of your body mattered more than your overall weight:
| Factor | Odds ratio |
|---|---|
| High waist-to-hip ratio | 2.44 |
| High waist circumference | 1.49 |
| High BMI | 1.21 |
A high waist-to-hip ratio — a marker of central, abdominal fat — carried roughly double the risk of a high BMI alone, suggesting where fat is stored matters as much as how much of it there is.
On the protective side, the same review found that healthy behaviours cut risk substantially:
| Factor | Odds ratio |
|---|---|
| Fruit and vegetable intake | 0.81 |
| Mediterranean diet | 0.33 |
| Moderate physical activity | 0.24 |
An odds ratio below 1.0 means reduced risk, and moderate physical activity’s 0.24 stands out as the single strongest lever in this entire dataset — non-modifiable or modifiable.
What this means in practice
Age and family history set your baseline risk, and there’s nothing to be done about either. But the modifiable list is longer than most people expect, and it isn’t only about food and exercise — sleep quality and mental health carry odds ratios on par with, or larger than, smoking. If a parent or sibling has type 2 diabetes, that’s a reasonable trigger to pay closer attention to the factors that are within reach, rather than to treat the diagnosis as inevitable.
Frequently asked questions
If diabetes runs in my family, is it inevitable that I’ll develop it too? No. Family history raises relative risk by 2 to 6 times, but it is one input among several. The same research shows that physical activity and dietary pattern carry odds ratios strong enough to meaningfully offset elevated baseline risk.
Why does waist-to-hip ratio matter more than BMI? Waist-to-hip ratio reflects central (abdominal) fat specifically, which is more metabolically active than fat stored elsewhere. In the reviewed data, it carried a higher odds ratio (2.44) than BMI alone (1.21).
Can stress and poor sleep really raise diabetes risk as much as smoking? Based on the pooled odds ratios in this review, yes — anxiety (2.61) and depression (1.88) carried higher odds ratios than smoking (1.31) in the same analysis.
This article is for general information only and does not constitute medical advice. If you have a diagnosed diabetic or prediabetic condition, consult your doctor before making changes to diet, exercise, or supplement use.