Beyond BMI: The Need for a Nuanced View of Obesity Risk

According to the Centers for Disease Control and Prevention (CDC), the percentage of the U.S. population aged 40-69 defined as normal weight (BMI of 18.5-25) shrank from 41% to 32% between 1999-00 and 2015-16 while the percentage considered obese (BMI of 30+) grew from 27% to 36%. And while almost 14% of adults in Canada were considered obese in 1978,¹ 27% were in 2017.² Obesity among adolescents has also increased, with severe implications for long-term health and the likelihood of complications such as diabetes and cardiovascular disease.

At the same time, data show that BMI for individuals also continues creeping upward from early childhood through late middle age. A Canadian study measuring the average 5-year change in BMI for individuals in different age cohorts found that BMI increased for every age cohort, except for those over age 65.

These worsening obesity trends mean we are almost certainly underestimating real mortality risk —particularly for younger applicants and for those starting out with a BMI in the obese range.

Adolescents with high BMIs simply have more time to develop resulting complications such as diabetes and cardiovascular disease. This is compounded by the fact that they are also likely to continue gaining weight over time given individual BMI migration trends. So current crediting and offsetting programs for adolescents with high BMIs are likely underestimating mortality risk.

In addition, the upward migration of BMI in the population overall has a disproportionate impact on mortality risk for those who are already moderately (BMI of 35-40) or severely (BMI of 40+) obese. So while an individual’s migration from a BMI of 24 to a BMI of 26 over 20 years does not significantly change their mortality risk, a two-point migration from 35 to 37 does.

Rather than rely on older approaches to address the risks associated with these trends, Munich Re is combining state-of-the-art predictive analytics and industry-leading underwriting and medical expertise to push the envelope. We are identifying innovative ways to assess and mitigate this growing concern to help carriers successfully position their businesses in a risk-informed way.