Frequently Asked Questions
Is BMI accurate for athletes?
No, not reliably. A muscular athlete can have a BMI in the overweight range despite very low body fat. For example, a 6-foot NFL running back at 220 lb has a BMI near 29.8 (overweight) but may carry only 8-12% body fat. For athletic populations, body fat percentage measured by DEXA or skinfold calipers is a better indicator.
Is the same BMI scale used for children?
No. For children aged 2-19, BMI is calculated using the same formula but read against age- and sex-specific growth charts. The CDC uses percentile categories: underweight (< 5th), healthy (5th-84th), overweight (85th-94th), and obese (≥ 95th). Adult cutoff numbers do not apply.
How do I lower a high BMI safely?
A 300-500 kcal/day deficit with adequate protein (1.6-2.2 g/kg/day) and resistance training preserves lean mass. Aim for 0.5-1% of body weight per week; faster loss comes disproportionately from muscle and water. This is general information - consult a doctor or registered dietitian for a personalized plan.
Why height squared rather than cubed?
A true volume ratio would use cubed height, but empirically adult body weight scales closer to height squared. Using the square keeps BMI roughly independent of stature across the normal adult range, which is why it works as a simple population screen despite its imprecision.
Provided by AllCalculators.io
Free online calculators for everyday. No registration required.
General information only. Not medical advice.
Health & Medical Disclaimer: General information only. Not medical advice.
This calculator provides general health information only and is not medical advice. Results do not replace professional medical evaluation or diagnosis. Consult a licensed healthcare provider before making health decisions. Always seek immediate medical attention for emergencies.