BMI Result: 5ft 9in, 83 lbs (BMI 12.3) - Female
According to CDC and WHO standards, a BMI of 12.3 is classified as Underweight.
A female who is 5ft 9in tall and weighs 83lbs has a BMI of 12.3, which falls into the Underweight category used by the CDC and WHO for adults.
| Category | BMI Range |
|---|---|
| Underweight | < 18.5 |
| Underweight | < 18.5 |
| Obese | ≥ 30 |
Healthy weight range for 5ft 9in: 125 lbs – 169 lbs
Metric: 175.3 cm, 37.6 kg
📏 Healthy waist circumference for your height: 30" – 35" (below 35" for female)
So you're 5ft 9in and weigh 83lbs. Your BMI is 12.3, which falls into the Underweight category according to CDC and WHO standards. Let's break down what this means for your health.
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Understanding Your BMI
A BMI below 18.5 may indicate nutritional insufficiency. According to the CDC, this range is associated with increased risk of bone density loss and immune function decline. Consulting a healthcare provider is recommended for a thorough nutritional assessment.
What This Means for Your Height
For women of average height, BMI is a reliable screening tool. Pair it with waist circumference for a more complete health picture.
Weight & Threshold
Gaining approximately 42.0 lbs would bring your BMI to 18.5, the start of the next category.
⬆️ Gaining approximately 42.0 lbs would put you in the Normal BMI range.
Waist & Health
The CDC recommends that non-pregnant women keep waist circumference below 35 inches. A waist-to-height ratio below 0.5 is also associated with lower health risks.
Age Context
For adults 45-64, metabolic health becomes increasingly important. At 56 years old, a woman at 5ft 9in and 83lbs has a BMI of 12.3, which falls into the Underweight category.
For adults in this age range, maintaining stable weight and regular physical activity is key to preserving metabolic health.
👉 Calculate your Body Fat Percentage for a more complete health assessment.
👉 Try our Athlete BMI Calculator if you have higher muscle mass.
Health Analysis
Recommendations
General Health
A BMI of 12.3 is below the CDC and WHO healthy range of 18.5-24.9. This may indicate nutritional insufficiency. Consulting a healthcare provider is recommended for a thorough nutritional assessment.
Monitoring
In addition to BMI, pay attention to waist circumference. The CDC recommends females stay under 35 inches. Regular tracking of your measurements over time provides the most useful insight into your health trends.
Next Steps
If you're concerned about your weight or body composition, a healthcare provider can offer personalized guidance based on your full health profile.
Personalized Notes
Physical Activity
For a woman at 5ft 9in, light strength training 2-3 times per week can help build muscle mass. Avoid excessive cardio which burns additional calories. The CDC recommends consulting a healthcare provider before starting any new exercise program.
Health Risks
With a BMI of 12.3 for a 5ft 9in woman, the underweight range is associated with increased risk of bone density loss and immune function decline. Consulting a healthcare provider is recommended for a thorough nutritional assessment.
Frequently Asked Questions
Is 83lbs overweight for a 5ft 9in woman?
How common is a BMI of 12.3 for a 5ft 9in woman?
How does a BMI of 12.3 affect health for a 5ft 9in woman?
How do I calculate my BMI at 5ft 9in and 83lbs?
Related Tools & Articles
💡 About this calculation: BMI = (83 × 703) ÷ (69 × 69) = 12.3 | Metric: 175.3 cm, 37.6 kg
📖 Recommended reading:
Editorial Review: This page was generated by the BMI Calculator Web Editorial Team and reviewed at template and content-pool level for accuracy and guideline alignment by Dr. Sarah K. Johnson, PhD, RD. All content is aligned with current WHO, CDC, and NIH guidelines.
Published: 2026-08-19