We hear the term “overweight” thrown out often, but what is the best way to know whether we are truly overweight?
The two most common ways determine if someone is overweight is to measure the Body Mass Index (BMI) or waist circumference. Both have limitations when used on their own, that’s why it’s best to measure both together to arrive at the most reliable conclusion.
Body Mass Index (BMI)
Body Mass Index (BMI) is calculated using your height and weight. The formula for calculating your BMI is:
Weight (Kg)/[Height (m)]2
The BMI is an estimate of body fat and can indicate your risk for diseases which can occur with more body fat. In other words, the higher your BMI, the higher your risk for certain diseases such as heart disease, high blood pressure, type 2 diabetes, gallstones, breathing problems, and certain cancers. The classifications of weight based on your BMI scores are as follows:
Below 18.5 = Underweight
18.5–24.9 = Normal weight
25.0–29.9 = Overweight
Over 30.0 = Obesity
Although BMI can be used for most men and women, it does have some limits:
It may overestimate body fat in athletes and others who have a muscular build.
It may underestimate body fat in older persons and others who have lost muscle.
Measuring waist circumference helps screen for possible health risks that come with being overweight and obese. The waist circumference measures the fat around your waist and not at your hips. Waist circumference is measured in inches. Those with a higher waist circumference are at a higher risk for heart disease and type 2 diabetes. This risk is increased in people with a waist size that is more than 35 inches for women or 40 inches for men. To correctly measure your waist, stand and place a tape measure around the middle of your abdomen, just above your hipbones. For the most accurate results, measure your waist just after you breathe out.
We can’t emphasize enough the importance of weight loss for those who are considered overweight. Even a small weight loss (between 5 and 10 percent of your current weight) will help lower your risk of developing diseases associated with obesity.
Remember, both BMI and waist circumference measurements have limitations when used on their own, so it’s best to measure both together for the most accurate determination of your weight status.