BMI Calculator
Calculate your Body Mass Index and understand how your weight relates to your diabetes risk. BMI is a widely used screening tool that can help identify weight ranges that may be associated with higher health risks.
WHO BMI Categories & Diabetes Risk
| Category | BMI Range | Diabetes Risk |
|---|---|---|
| Underweight | < 18.5 | Below average |
| Normal weight | 18.5 – 24.9 | Average |
| Overweight | 25.0 – 29.9 | Increased |
| Obese Class I | 30.0 – 34.9 | High |
| Obese Class II | 35.0 – 39.9 | Very high |
| Obese Class III | ≥ 40.0 | Extremely high |
Medical Disclaimer
BMI is a screening tool, not a diagnostic measure. It does not account for muscle mass, bone density, or fat distribution. Always consult a qualified healthcare professional for a comprehensive health assessment.
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What Does BMI Measure?
Body Mass Index (BMI) is a simple numerical measure derived from a person's weight and height. It provides a quick screening value that categorizes individuals into weight status groups: underweight, normal weight, overweight, and obese. BMI is calculated as weight in kilograms divided by height in meters squared (kg/m²).
BMI and Diabetes Risk
Research consistently shows that excess body weight — particularly abdominal fat — is one of the strongest modifiable risk factors for type 2 diabetes. As BMI increases above the normal range, insulin resistance tends to increase, making it harder for cells to respond to insulin. People with a BMI of 30 or above have a substantially higher lifetime risk of developing type 2 diabetes compared with individuals in the normal BMI range. Even modest weight loss (5–10% of body weight) can significantly improve insulin sensitivity and reduce diabetes risk.
Limitations of BMI
While BMI is a useful population-level screening tool, it has important limitations. It does not distinguish between fat mass and lean muscle mass, meaning highly muscular individuals may be classified as overweight despite having healthy metabolic profiles. BMI also does not account for fat distribution — visceral (abdominal) fat carries greater health risks than subcutaneous fat. Additionally, BMI thresholds may differ across ethnic groups. Always discuss your weight, body composition, and metabolic health with a qualified healthcare professional.
Sources
- World Health Organization. Obesity and overweight. WHO Fact Sheets, 2021.
- Abdullah A, et al. The magnitude of association between overweight and obesity and the risk of diabetes. Obes Rev. 2010;11(5):322-329.
- Guh DP, et al. The incidence of co-morbidities related to obesity and overweight. BMC Public Health. 2009;9:88.
Medical disclaimer: This tool is for informational and educational purposes only and does not constitute medical advice. BMI is a screening tool, not a diagnostic measure. Always consult a qualified healthcare professional before making changes to your diet, exercise, or treatment plan.