Not Weight, Not Body Shape: Scientists Say These Measurements Are More Important For Health

For many decades, weight gain has been represented culturally as a harbinger of doomed health. But the root of this fear is not based in science but in stigma. As more and more research emerges, we are discovering that weight is not the immediate litmus test for wellness we have been sold. There are many other metrics that can be measured more accurately and reveal much more about bodily health, including blood pressure and cholesterol. However, as with all things, it is important to remember that your body is composed of many systems working in conjunction, and thus far, no one metric has been able to fully distinguish a healthy body from an unhealthy one.

Many of the touted concerns for people who present with bodies that are larger than societal ideals revolve around cardiovascular health. This is likely related to the known link between metabolic deficiencies and poor cardiovascular outcomes, along with the presumed link between higher weight and poor metabolism. However, there are many people with obesity as indicated by BMI who are, in fact, metabolically healthy. While metabolic disorders can alter weight gain, high weight levels do not automatically mean that a metabolic issue is present. Therefore, investigating a patient's metabolism through lipid levels, blood pressure, and insulin sensitivity would likely present a better overall picture of health as opposed to simply comparing their weight-to-height ratios.

As mentioned above, many people can have BMIs in the above-average range and still be metabolically healthy. Therefore, analyzing indicators of proper metabolic function is much more useful in gaining an understanding of someone's overall health. Moreover, these are generally accurate measures with much more concrete evidence to back them up in the literature.

One such metric is cholesterol. High levels of low-density lipoprotein (LDL) cholesterol can build up in your blood vessels. When this happens, it can lead to the formation of a blood clot. Blocking blood flow is very dangerous for a number of reasons, as blood is the oxygen and nutrient delivery system in our bodies. If a blood clot occurs leading to the brain, this will result in a stroke. Whereas if a blood clot forms on the way to the heart, a heart attack can occur. Importantly, high LDL cholesterol is a leading cause of cardiovascular issues, which are a common cause of death. Physicians can perform a lipid panel to assess cholesterol levels and better predict the risk of cardiovascular issues. 

Another metabolic factor that has the greatest association with cardiovascular health is blood pressure. Typically, this is something a healthcare provider measures each time you go to an appointment. High blood pressure can lead to damaged blood vessels, having detrimental downstream effects, including stroke and heart failure. Therefore, paying attention to blood pressure and cholesterol is much more likely to provide an accurate picture of your health.

Understanding how weight was centered as the immediate display of health requires understanding the flaws in our measurements. Much of our data regarding weight is organized by a metric known as the body mass index (BMI). This is calculated by body weight divided by squared height. Originally designed by a mathematician (not a health scientist), Adolphe Quetelet in the 19th century, this equation was meant to investigate what constituted the "normal man." Later, in 1972, a physiologist named Ancel Keys would term the equation "body mass index" and trumpet it as an efficient measure for population studies. The study that he conducted to support this included over seven thousand men.

A couple of red flags might have caught your eye. First, this method was never intended to indicate health — it was math paired with the intent to determine what was "normal." Secondly, this "normal" was only calculated with cis-men. We know that there are variations between sexes in height-to-weight ratios and that the exclusion of people assigned female at birth in research studies is a persistent shortcoming in health research. Moreover, sex does have a known influence on metabolism and other aspects of health that we discussed above, like cardiovascular conditions.

While there are data that highlight an association of BMI with cardiovascular diseases, these vary greatly based on population, with the most predictive outcomes for White people of European descent. Therefore, the other metrics outlined above are generally more effective.