function calculateHealthMetrics() {
var weightKg = parseFloat(document.getElementById('weightKg').value);
var heightCm = parseFloat(document.getElementById('heightCm').value);
var waistCm = parseFloat(document.getElementById('waistCm').value);
var genderMale = document.getElementById('genderMale').checked;
var bmiResultDiv = document.getElementById('bmiResult');
var whtrResultDiv = document.getElementById('whtrResult');
var overallAssessmentDiv = document.getElementById('overallAssessment');
bmiResultDiv.innerHTML = 'BMI: -';
whtrResultDiv.innerHTML = 'Waist-to-Height Ratio: -';
overallAssessmentDiv.innerHTML = 'Overall Assessment: -';
if (isNaN(weightKg) || weightKg <= 0 || isNaN(heightCm) || heightCm <= 0 || isNaN(waistCm) || waistCm <= 0) {
overallAssessmentDiv.innerHTML = '
';
return;
}
// Calculate BMI
var heightM = heightCm / 100;
var bmi = weightKg / (heightM * heightM);
var bmiCategory = ";
if (bmi = 18.5 && bmi = 25.0 && bmi <= 29.9) {
bmiCategory = 'Overweight';
} else {
bmiCategory = 'Obese';
}
bmiResultDiv.innerHTML = 'BMI: ' + bmi.toFixed(2) + ' (' + bmiCategory + ')';
// Calculate Waist-to-Height Ratio (WHtR)
var whtr = waistCm / heightCm;
var whtrCategory = '';
if (genderMale) { // Male categories
if (whtr = 0.43 && whtr = 0.53 && whtr = 0.58 && whtr <= 0.62) {
whtrCategory = 'High Risk (Obese)';
} else {
whtrCategory = 'Very High Risk (Severely Obese)';
}
} else { // Female categories
if (whtr = 0.42 && whtr = 0.49 && whtr = 0.54 && whtr <= 0.57) {
whtrCategory = 'High Risk (Obese)';
} else {
whtrCategory = 'Very High Risk (Severely Obese)';
}
}
whtrResultDiv.innerHTML = 'Waist-to-Height Ratio: ' + whtr.toFixed(2) + ' (' + whtrCategory + ')';
// Overall Assessment
var assessmentText = '';
var assessmentColor = 'black';
if (bmiCategory === 'Normal weight' && whtrCategory === 'Healthy') {
assessmentText = 'Your BMI and Waist-to-Height Ratio both indicate a healthy range. Keep up the good work!';
assessmentColor = 'green';
} else if (bmiCategory === 'Normal weight' && (whtrCategory.includes('Risk') || whtrCategory.includes('Obese'))) {
assessmentText = 'While your BMI is in the normal range, your Waist-to-Height Ratio suggests increased abdominal fat, which can be a health risk. Focus on reducing waist circumference.';
assessmentColor = 'orange';
} else if (bmiCategory === 'Overweight' && whtrCategory === 'Healthy') {
assessmentText = 'Your BMI is in the overweight category, but your Waist-to-Height Ratio is healthy. This might indicate a muscular build, but it\'s still wise to monitor your weight.';
assessmentColor = 'orange';
} else if (bmiCategory === 'Overweight' && (whtrCategory.includes('Risk') || whtrCategory.includes('Obese'))) {
assessmentText = 'Both your BMI and Waist-to-Height Ratio indicate you are overweight with increased health risks. Consider lifestyle changes to improve both metrics.';
assessmentColor = 'red';
} else if (bmiCategory === 'Obese' || whtrCategory.includes('High Risk') || whtrCategory.includes('Very High Risk')) {
assessmentText = 'Your BMI and/or Waist-to-Height Ratio indicate obesity and significant health risks. It is highly recommended to consult a healthcare professional for guidance.';
assessmentColor = 'red';
} else if (bmiCategory === 'Underweight') {
assessmentText = 'Your BMI indicates you are underweight. It\'s advisable to consult a healthcare professional to ensure you are meeting your nutritional needs.';
assessmentColor = 'orange';
} else {
assessmentText = 'Based on your metrics, it\'s recommended to review your lifestyle choices. Consult a healthcare professional for personalized advice.';
assessmentColor = 'black';
}
overallAssessmentDiv.innerHTML = 'Overall Assessment:
Understanding Your Body Composition: BMI and Waist-to-Height Ratio
Assessing your body composition is a crucial step towards understanding your overall health. While Body Mass Index (BMI) has long been a standard tool, combining it with the Waist-to-Height Ratio (WHtR) provides a more comprehensive picture, especially regarding abdominal fat, which is linked to various health risks.
What is BMI?
The Body Mass Index (BMI) is a simple calculation using your height and weight to estimate if you are underweight, normal weight, overweight, or obese. It's calculated as: BMI = weight (kg) / (height (m))^2.
BMI Categories:
- Underweight: Less than 18.5
- Normal weight: 18.5 – 24.9
- Overweight: 25.0 – 29.9
- Obese: 30.0 or greater
While BMI is a useful screening tool, it has limitations. It doesn't distinguish between fat and muscle mass, meaning a very muscular person might have a high BMI without being unhealthy, and it doesn't account for fat distribution.
What is Waist-to-Height Ratio (WHtR)?
The Waist-to-Height Ratio (WHtR) is a simple and increasingly recognized indicator of central obesity, which is the accumulation of fat around the abdomen. This type of fat (visceral fat) is metabolically active and poses a higher risk for conditions like heart disease, type 2 diabetes, and stroke, even in individuals with a "normal" BMI.
It's calculated as: WHtR = Waist Circumference (cm) / Height (cm).
How to Measure Your Waist Circumference Correctly:
- Stand upright with your feet together and breathe out normally.
- Locate the top of your hip bone and the bottom of your lowest rib.
- Place a measuring tape midway between these two points, usually around your belly button.
- Ensure the tape is snug but not compressing your skin, and parallel to the floor.
- Read the measurement.
Interpreting Your WHtR:
Unlike BMI, WHtR thresholds are generally more consistent across different populations and ages for identifying health risks. A common guideline is to keep your waist circumference less than half your height.
General WHtR Categories (Adults):
- Below 0.4: Extremely Slim (potentially underweight)
- 0.4 to 0.49: Healthy range
- 0.5 to 0.59: Increased risk (overweight/pre-obese)
- 0.6 or greater: High risk (obese)
Our calculator uses slightly more refined, gender-specific guidelines for a more accurate interpretation.
Why Use Both?
Combining BMI and WHtR offers a more robust assessment of health risks. A person with a normal BMI but a high WHtR might still be at risk due to excess abdominal fat. Conversely, someone with a slightly elevated BMI but a healthy WHtR might have a higher muscle mass. This dual approach helps you and your healthcare provider make more informed decisions about your health and lifestyle.
Disclaimer: This calculator provides general information and is not a substitute for professional medical advice. Always consult with a healthcare professional for personalized health assessments and recommendations.