BMI and Health Metrics: Beyond the Basic Number
BMI gets criticized, but dismissing it entirely is also a mistake. Here is how I pair it with other metrics for a complete picture. BMI gets a lot of criticism, and much of it is fair. But the criticism sometimes swings too far the other way, dismissing BMI entirely when it is still a useful screening tool. After tracking my own health metrics for years, I have settled on a balanced approach: I calculate BMI, but I pair it with other metrics that address its weaknesses. Here is how I use each one and what it tells me about my own body. BMI: The Quick Screening Tool BMI is weight in kilograms divided by height in meters squared. The formula is simple, and the categories are standardized: under 18.5 is underweight, 18.5 to 24.9 is normal, 25 to 29.9 is overweight, and 30 or above is obese. I use BMI as a first pass. If my BMI shifts significantly, it signals that something has changed and I should investigate further. Metric: weight(kg) / height(m)^2 Imperial: (weight(lb) * 703) / height(in)^2 Example: 175 lb, 70 in tall (175 * 703) / (70 * 70) = 123,025 / 4,900 = 25.1 Category: just into overweight The well-known limitation is that BMI does not distinguish muscle from fat. When I started lifting weights seriously, my BMI crept into the overweight range, but my body fat percentage was declining.