As we've heard for years, stepping on the scale isn't a good way to measure your health - but neither is your body mass index (BMI).
A 2016 study found that your BMI doesn't actually reveal whether your body is healthy or not. While it can be helpful, according to registered dietitian and nutritionist Sonya Angelone, it's far from the be-all-and-end-all of health.
The BMI is calculated by the person's weight divided by their height, and dates way back to the 1800s - so as you can imagine, it's a little outdated by now. Depending on the calculation, the person can be classified as underweight, normal, overweight or obese.
Angelone says the purpose of the BMI is not about aesthetics or to shame you, but is looking at your risk of disease.
“There are studies that show that people who have higher BMIs have higher mortality rates. The point, really, of the BMI is to look at the relationship between body weight and your disease and death rate. Because people who are overweight and obese have an increased risk for a lot of diseases, including coronary artery disease, diabetes, gallbladder disease, high blood pressure, osteoarthritis, stroke, and tongue cancer.”
She also notes however that it has many limitations: “It is not an accurate measurement of health risk for an individual. When a study looks at a group of people, that doesn’t apply to you as an individual and people never quite understand that. It can indicate that you might be just like that group, but you also might not be just like that group.”
“What’s really important for somebody’s weight is to know the quality of that weight. Is it fat or muscle? And BMI doesn’t really tell you that,” Angelone said. “It doesn’t differentiate between muscle mass and fat mass. The goal is to have more muscle in general," when it comes to being healthy.
A better way of measuring your health, according to Angelone, is body-fat measurement. This can give you a better idea of how much of your body is fat vs. muscle. There are two ways of doing this, the more common being calipers - “The problem is is that you have to have somebody who really knows how to use calipers." It's also probably good to have the same person measure you each time if you are doing this across a few different periods.
Another more helpful way to measure your health is using waist measurements. Your waist circumference, waist-to-hip ratio and waist-to-height ratios are all helpful. The US National Institute of Health states that women are at greater risk of heart disease and type two diabetes if their waist measures more than 35 inches (or 40 inches for men).
Research has found that people have a “higher risk of diabetes, dyslipidemia, hypertension, and cardiovascular disease because of excess abdominal fat.”
Your waist-to-hip ratio (WHR) is your waist circumference divided by your hip circumference. Your health risk increases according to the World Health Organisation if your WHR is above .85 (or .90 for men).
Your waist-to-height ratio (WHtR) is your waist circumference divided by your height. The ratio should be less than 0.5.
These measurements are all more helpful in showing your true health than weight or BMI. Angelone also noted that drastic diets and fads will not help to make you healthier. The number one thing she recommends to remain healthy is exercise: “Just make sure you’re exercising. If people are not exercising enough, which includes aerobic and some strength training, then they need to figure out a way to do that if they really, truly want to be optimally healthy.”