How is bmi flawed

In the United States, there is a weight and obesity problem. It makes sense for doctors and health professionals to be on the lookout for specific health issues. The BMI focuses on two numbers: weight divided by height squared. With the BMI scores, certain groups can have their body fat miscalculated by these measurements. As more people are placed in the overweight or obese categories, the BMI is coming under attack. BMI does not take into account the difference between fat and muscle, so its prediction for weight-related health issues is not accurate.

However, they are unhealthy based on bad cholesterol levels, triglycerides, blood pressure, glucose, and C-reactive protein tests.

On the other side, 50 percent of overweight and 29 percent of obese people were healthy based on their medical examinations. There are certain groups of people who should not use BMI to measure their overall health and body fat. They include the following:. Nursing or pregnant women should find other ways to measure body fat. Women tend to have a higher body fat percentage and weight during this time.

This higher body fat is due to supplying nourishment to the infant. Even nonpregnant women should not take read too deeply into the BMI numbers. When compared to men, women will have higher levels of body fat. If you are Asian and want an accurate body fat measurement, you also might need to find a different measurement than BMI. This is not true.

Your fat cells are like balloons; they get bigger when you gain weight, and they get smaller when you lose weight. Now, the safest place to store fat is in your fat cells. When the cells become full however, the fat ends up in places not designed to store fat in large amounts, such as our muscles or our liver for example, and that is when we tilt into diseases such as type 2 diabetes and other metabolic conditions.

So, here is the interesting thing. Depending on our genes, our fat cells, or adipocytes, are able to expand to different sizes before becoming full. Whereas other ethnicities including white people and, famously, Polynesians for instance, can gain a lot more weight before becoming ill, in large part, due to the expandability of their adipocytes.

The degree to which our fat cells can expand is a powerful genetically influenced trait, and informs our differing safe fat-carrying capacities. As she writes, "At the beginning of the year, I started having very bad thoughts when my body was brought into a conversation.

I would wear four bras to try and cover up my back fat, and I would try to wrap ace bandages around my stomach so I would look skinnier. Tessa's mother took her to a doctor for a checkup, and the doctor said she was just fine. Tessa reminds us that the problem with BMI is that it only gives us an indirect measure of one thing — body fat — and that sometimes doesn't reflect health.

When we talk about BMI, we should see it as something that's more provisional, and not the final answer. Our mission has never been more vital than it is in this moment: to empower through understanding.

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By choosing I Accept , you consent to our use of cookies and other tracking technologies. Why BMI is a flawed measure of body fat, explained by an eloquent year-old. Reddit Pocket Flipboard Email. When her teacher asked for her BMI in a recent health quiz, the eighth-grader responded with an eloquent diatribe about why the calculation is fraught with "obvious flaws" and why it's harmful to one's body image: BMI is an outdated way of defining normal weight, under weight, over weight, and obesity by taking one person's height divided by their weight.

Why BMI is flawed We do have an obesity and weight problem in the US, and there's good reason to be on the lookout for these problems. Not only is the BMI not necessarily an inclusive measure of health, but it's also an inaccurate one. With the BMI, weight and height are the only two measurements taken to reach a conclusion on how "healthy" someone is; BMI doesn't take into account bone density bone is twice as dense as fat , muscle mass, nor the fact that there are four main types of body fat— not all of which are harmful to human health.

Essentially, the BMI is an inherently flawed system that serves to center a white, male, European standard of health as one that's universal to all. Before even walking into the doctor's office, many people's natural bodies are deemed "unhealthy" or "healthy," defined as such within the confines of white-centered standards.

BMI is often used to predict a person's risk for certain conditions like heart disease, high blood pressure, and diabetes , but it is an imperfect measure for many BIPOC communities. For example, the high rate of chronic diseases among Black Americans has long been chalked up to obesity rates, but research shows that Black Americans are over-indexed for obesity thanks to BMI —meaning that weight might not necessarily be the cause of these disparities.

Take diabetes risk, which is commonly associated with a BMI of 30 or higher. This means that an Asian American person could be at risk of diabetes despite being at a BMI that's considered healthy. The BMI's Eurocentric framing might also mean that people of color with larger bodies might be more likely to have health concerns chalked up to their weight. Starla Shines Gomez , RDN, recalls a time when her sister went to her doctor for an annual physical; her BMI and abnormal lab results—which showed an increase in blood sugar— prompted her doctor to place her on a medication for diabetes a condition commonly associated with obesity.

Since Gomez and her sister live together and eat more or less the same meals every day, the results didn't sit quite right with the dietitian. She encouraged her sister to go back to the office and insist her doctor look into her symptoms beyond her weight.

Eventually, her physician referred her to an endocrinologist, who diagnosed her with a metabolic disorder unrelated to diabetes that may have gone untreated if Gomez's sister hadn't demanded better care. And that, genetically, they may never be able to fit in.