You’ve probably heard it at a check-up or seen it on a fitness app – your BMI. Body Mass Index (BMI) is a number that tells if an individual is underweight, overweight or within the healthy weight range. It is quick, easy and it is everywhere. But here’s the catch – BMI does not always provide you with a full picture of health.
The question we ask is, ‘Can a single number define our health?’ Not really! If you’ve ever felt confused by your BMI score or wondered why it does not match how you feel, you’re not the only one.
In this post, you will understand BMI better and get to know the other parameters you can track to get an accurate picture of your health.
What is BMI and How It’s Calculated
Body Mass Index (BMI) is a simple calculation to determine body fat in an individual. It was created by a Belgian Mathematician in the 1830s and has been in use for more than a century for public health screenings. Widely used to classify weight ranges, you can get your BMI by dividing your weight (in kilograms) by height (in meters squared).
BMI = weight (kg) ÷ height (m²)
However, BMI was never designed to measure individual health as it doesn’t take into account muscle mass, bone structure or fat distribution. So two people with the same BMI can have very different health profiles.
If you’re wondering what BMI is, overweight or obese, you can check the full breakdown on BMI for overweight and obese to see where you land.
| Category | BMI Range |
| Underweight | Less than 18.5 |
| Normal weight | 18.5 to 24.9 |
| Overweight | 25 to 29.9 |
| Obese | 30 and above |
When it comes to healthy vs unhealthy BMI ranges, underweight, overweight and obese categories are all considered to be at health risks such as the development of diabetes, high cholesterol, heart disease while people having a normal weight are considered healthy.
BMI scale for obesity classification
Below is how BMI defines obesity.
| Classification | BMI Range | Health Risk |
| Normal weight | 18.5 to 24.9 | Low |
| Overweight | 25 to 29.9 | Increased |
| Obesity Class I (Mild) | 30 to 34.9 | High |
| Obesity Class II (Moderate) | 35 to 39.9 | Very High |
| Obesity Class III (Severe) | 40 and above | Extremely High |
Limitations of BMI as a Health Metric
BMI is everywhere – from gym posters to doctors’ charts – but it leaves out a lot. Here’s what BMI doesn’t tell you.
- Muscle mass: A bodybuilder and someone with excess fat can have the same BMI. One is fit, the other may not be.
- Bone density: People with heavier bones often score higher on the BMI scale. Even if they’re in great shape, their BMI tells a different story.
- Fat distribution: Where fat is stored on your body matters a lot. Having belly fat (abdominal fat) has more health risks than the fat in the hips or thighs. BMI doesn’t make this difference.
It also misses the mark across different groups as age, gender and ethnicity affect how and where the fat is stored on the body. So a BMI of 25 might mean one thing for a young athlete and something else for a sedentary adult.
BMI can be a useful screening tool but it’s not a diagnosis. If your BMI feels off it might be time to look beyond the chart and ask better questions about your health.
Alternative Health Indicators to Consider
There are better ways to understand your health that look beyond weight and height and BMI. Here are three that matter:
1. Waist to hip ratio
This compares the size of your waist to your hips. Carrying more fat around your waist than your hips can increase your chances of heart disease and type 2 diabetes.
2. Waist circumference
This measures your abdominal fat. A waist size above 40 inches for men and 35 inches for women is linked to a higher risk of metabolic conditions.
3. Body fat percentage
This tells you how much of your body is made up of fat versus muscle, bone and water. A person with a high BMI but low body fat is likely in better shape than someone with a normal BMI and high fat percentage.
4. Metabolic health markers
These include blood pressure, cholesterol levels, blood sugar and more. You can have a “healthy” BMI and still be at risk if these are off.
So while the BMI chart for overweight and obese can be a helpful starting point, it is not the finish line.
Conclusion
BMI can be useful as an initial health analysis. But to get good insights, you need to take muscle mass, fat distribution and key health markers that matter into account. Whether you’re an athlete, an older adult or just curious about your health, it pays to look deeper.
Dig into parameters such as waist to hip ratio, body fat percentage and metabolic markers to get a clearer picture. If you’ve ever questioned your BMI score, you’re asking the right questions. Real health starts with real data.
