Anyone thinking about weight loss or looking to establish if their current weight is healthy are usually told to check their body mass index (BMI).
There are various BMI calculators available online, while healthcare professionals also use this measurement to calculate the healthy weight of an individual, so it’s certainly regarded as a handy tool when it comes to weight loss and understanding your current weight
But is BMI still an accurate way to measure weight and weight loss progress? Recent studies have indicated that BMI may not be as accurate as many believe, with the measurement having several limitations that were previously overlooked.
Is BMI still a useful tool measuring weight loss? Let’s look closer to find out more.
What is BMI?
Before getting into how useful BMI is it helps to understand what it is. Body mass index is a measurement used to establish how healthy a person’s weight is. The calculation is made by dividing a person’s weight in kilograms by their height in meters squared, with the resulting measurement being their BMI.
Because BMI accounts both height and weight when calculating a person’s healthy weight range, it’s believed to be one of the most effective ways to establish whether you are overweight, obese, underweight, or a healthy weight.
BMI ranges help establish whether a person’s weight is considered healthy or not. Once you measure your BMI, you check it against BMI ranges to see establish how healthy or unhealthy the weight is. BMI ranges include:
- Healthy – BMI range between 18.5 and 24.9
- Overweight – BMI range between 25 and 29.9
- Obese – BMI range between 30 and 39.9
- Underweight – BMI range below 18.5
Given how simple it is to calculate your BMI and check it against a BMI range using a tool such as the one from HCG injections, it’s easy to see why BMI is considered a useful tool for weight loss. For instance, if you’re trying to lose weight and want to measure your progress, you just need to keep calculating BMI by dividing your weight by your height in metres squared and once you hit the healthy BMI range you know your weight loss is a success.
Or is it?
It is true that measuring your BMI can indicate whether you’re overweight or underweight, while reducing your BMI is a sign that you’re successfully losing weight. However, there are limitations to BMI that should always be considered by people looking to determine how healthy their weight is.
There are some notable limitations of BMI that mean it’s not always the most useful tool for measuring weight loss. For example, BMI doesn’t measure bone density, muscle mass, and gender, all of which influence a person’s weight.
Because of this BMI ranges are often misleading. For instance, people that carry a lot of muscle mass (such as body builders and athletes) may find themselves with an overweight BMI despite not showing any visible signs of body fat.
This is because muscle is denser than fat, so muscular people often have similar weights to people carrying excess body fat. Similarly, people that lose muscle mass may find their BMI range is now considered healthy even if they have a lot of body fat.
Another factor that should be considered when calculating a healthy BMI is the ethnic group. People of Asian are often at a higher risk of developing health issues with BMI range below 25, meaning their healthy BMI range could be misleading.
These are just a few examples of how BMI ranges are often misleading so may not be the best for measuring weight loss.
So, the high and low end of the BMI range usually paint an accurate picture of someone’s weight, being either obese or underweight. The middle range is where things become less clear, as other variables may cause the BMI range to become clouded.
The Importance of Waist Size
Waistlines should also be considered when using BMI to measure weight loss. This is because it provides a more accurate measurement of body fat relating to weight and height. For example, people that have a healthy BMI range that haven’t considered waist size may need to lose weight.
Having too much fat around the stomach with a healthy BMI range means a person should probably lose some weight, as it is not technically healthy, increasing the risks of developing chronic illnesses like heart disease and type 2 diabetes.
Therefore, if you find yourself in a healthy BMI range but still have a fair amount of fat around your stomach then you may want to consider losing weight.
To establish this, you can measure your BMI and waist size to get a more accurate idea of how heathy your weight is. Simply grab a measuring tape and measure your waist, breathing out as you take the measurement.
No matter your BMI range, if your waist size is 37-inches (male)/31.5-inches (female) or more then you should try losing weight. If these waist measurements are several inches above these, then you may be at an even higher risk of serious health issues.
Is BMI a Useful Tool?
While there are several limitations to the accuracy of BMI, it can still be a useful tool for measuring weight loss, espiecally when considering other variables. If you have a very high BMI range then you do need to lose weight, while reducing it significantly shows clear signs of successful weight loss.
But when your BMI is the mid-range, it’s important to consider other variables such as your gender, muscle mass, ethnic group, and waist size. Thankfully, most medical professionals consider all these factors along with the BMI measurement, giving you a much more accurate representation of your weight.
Also, many BMI calculators online now have the option of including your sex, ethnic group, and waist size, so they still have plenty of use. It’s just important to understand the limitations and how they impact your BMI reading and your weight loss progress.