Is Your BMI Really A Good Accurate Measurement Of Health?


It’s generally pretty known that your body mass index takes into account your own height and weight rather than your fat total, although, it’s still considered a valid way to screen for heart risks, based on an English study of nearly 3,000 young adults published in the Journal of the American College of Cardiology.

Also known as the ALSPAC study, or more commonly Avon Longitudinal Study of Parents and Children, the new study began by tracking the health of 2,840 children from birth through to the age of 18. As part of the study, participants had their health, height and weight regularly measured, in addition to undergoing X-ray imaging at ages 10 and 18 to assess an individuals fat content. The goal of the recent analysis? To simply see how body mass index and fat content relate together, especially in regard to an individuals heart health.

So, what is Body mass index? Body Mass Index, also known as BMI is a ratio of height to weight, which generally helps determine whether individuals are underweight, normal, overweight or obese according to predetermined medical charts. BMI has been criticised heavily in the past for not including fat in its calculations, and therefore have created large speculation that it’s not necessarily the most accurate form of measurement, which we know has a big impact on heart health. For many, BMI has been rumoured to potentially be a common too that is just too simple of a tool to accurately assess health. However, results of the new ALSPAC study has now squashed all rumours and confirmed that BMI remains  as a useful and scientifically correct measurement for evaluating BMI, and in turn, cardiovascular health in children and young adults.

Over the course of the new medical study, researchers continuously tracked 230 markers of heart health in their participants, including blood pressure, cholesterol, and inflammation. During the testing,  researchers discovered that increases in BMI and fat between the ages 10 and 18 resulted in poorer markers of heart health. However, the study authors note that the association between increased fat content and cardiovascular risk was stronger than that found in BMI. Additionally, they also discovered that fat in the midsection appears far more harmful than fat in the legs or arms.

Dr. Joshua Bell, an epidemiologist at the University of Bristol who led the study, commented: “BMI is often criticised. Our study asked how useful it really is for detecting the health effects of obesity by pitching it against more objective body scan measures. We found that trunk fat is the most damaging to health, but that simple BMI gives very similar answers to more detailed measures. This is good news since BMI is widely measured and costs virtually nothing.”

“We’re now in a better position to understand obesity in the young thanks to participants of the Bristol-based Children of the 90s study—they, and all study participants, make new insights possible.”

“We now need to look at more detailed lean measures to see if other aspects protect against higher fat, and how this might differ between the sexes. This is more important than ever given stubbornly high rates of obesity worldwide.”

According to authors, the take home message for all readers is simply that the fat in our bodies is the driving factor behind increased heart risks. While an individuals BMI doesn’t necessarily consider fat in its calculations, it’s no doubt a useful tool that mirrors the results of fat testing and generally tests that are far more involved and costly than simply calculating your BMI.

So what exactly does all of this mean for patients? Experts on the topic have also noted that based on the findings, gaining fat in any area of your body is not considered at all good for health, especially in the first two decades of life. Children who are overweight or obese have much higher risk for health problems later in life. Therefore, BMI remains an important tool for screening for children at increased cardiovascular risk and hopefully motivating lifestyle change to promote better health.

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