What Dietitians Said About Ilona Maher’s BMI Video

We asked a few dietitians for their reactions to the video—here’s what they said: 

• Joanna Gregg, Registered Dietitian: “I love that Ilona loves and appreciates her body for what it can accomplish and not for her BMI or weight on the scale. It’s often easy to lose sight of that as BMI is used in healthcare as a determinant of health. A person at a healthy BMI can 100% be less physically fit than a person with an overweight BMI. Love your body for what it can do not for what size it is! Athletes have to train and fuel at a level that is unheard of in the general population and we need more strong women like Ilona to show our younger population what’s truly important.”
• Katherine Basbaum, Registered Dietitian: “A perfect real-life illustration of how BMI, like weight and like age, is just a number and should not be used as stand-alone data to judge or identify an individual’s health status or physical fitness. BMI is a tool, not a diagnosis, and Ilona Maher is a perfect example of this fact.”
• Stephanie Nelson, MyFitnessPal Lead Nutrition Scientist & Registered Dietitian: “Ilona was spot-on! BMI does not tell a story about a person’s worth or what they can do, much less tell a story about how healthy their body is.”
• Brookell White, Registered Dietitian: “Yep, you heard her right! BMI is calculated using someone’s height and weight. Because it’s only using these two measures, it doesn’t account for muscle mass or body fat percentage and therefore may not be a good indicator of obesity for athletes.”
• Daisy Mercer, Registered Dietitian: “I love her so much. BMI is not the end all be all and it is often a poor representation of someone’s overall health. It’s more important to look at the big picture and realize we are all built differently and have different activity levels that BMI can’t account for!”

Dietitians tend to know the facts when it comes to the usefulness of BMI. Maher said in the video that she discussed BMI with her own dietitian, including details about what the number means and its usefulness.

But in case you aren’t fully convinced, let’s dive a little deeper into what BMI is really all about. 

What is BMI?

BMI is just a math formula that divides a person’s weight in kilograms by the square of their height in meters. It was originally developed in the 19th century by a statistician to look at weight data on a population—not individual—level. 

While it has since been adopted by the World Health Organization (WHO) to classify individuals into categories like underweight, healthy weight, overweight, and obese, its usefulness has been widely debated.

Athletes like Maher often fall into the overweight or obese categories of the BMI, thanks to their impressive muscle mass. A key problem with BMI is that it fails to differentiate muscle from fat. 

“BMI is just a comparison of height to weight, nothing more,” Nelson says. “It doesn’t take into account how much muscle a person has, and by itself, it doesn’t say anything about health, lifestyle, or especially worth. BMI’s main usefulness is that it corrects for differences in height when assessing weight.”

So, it’s helpful when looking at large populations over time to see if weights are increasing or decreasing on average, while correcting for height. But, that doesn’t mean it should be applied on the individual level

What Should You Focus On Instead?

Rather than relying exclusively on BMI, pay attention to other indicators of health and fitness. For athletes, performance metrics specific to their sport and position are crucial. 

For most people, the following factors are more important when it comes to getting a full picture of your health, according to Nelson: 

• Body fat percentage (your doctor can measure this at your annual check-up!)
• Waist-to-hip ratio (you can measure these with a tape measure on a monthly basis to gauge changes)
• Overall diet quality (you can better gauge your eating patterns by tracking meals with MyFitnessPal)
• Lifestyle habits (you can focus on improving sleep, increasing physical activity, and reducing stress)
• Physiological risk factors (like blood glucose, cholesterol, and blood pressure)

“When it comes to preventing nutrition-related disease, many experts tend to care more about how much adipose tissue [or fat] is sitting around the organs for a long period of time,” says Nelson. “That’s the visceral or abdominal fat some people carry around their midsection.” 

“Other markers to look at include percentage of body fat and waist-to-hip ratio,” says Nelson. “But it’s also important to consider diet habits as well. Are you getting enough protein, fiber, fruits, veggies, and whole grains?” 

That’s another reason why tracking your meals can be very helpful. You’ll see how you stack up in terms of protein and fiber and have access to some useful insights when you use an app like MyFitnessPal. (Download the app for FREE today!)

Maher concluded her viral video by speaking directly to her heckler and reminding us all that she is an elite athlete performing on the biggest stage. 

It’s a powerful reminder that your BMI says nothing about what you’re capable of. When it comes to understanding your health, it can never be reduced to a single number, whether it’s BMI or the number on the scale. 

“BMI is only one teeny tiny piece of information and we should be aware of its limitations,” says Nelson.