Study: Healthy Waist Size May Be Bigger For Black Women

A new study finds that the 'healthy' waistline threshold may be slightly larger for African-American women than for white women.
A new study finds that the 'healthy' waistline threshold may be slightly larger for African-American women than for white women.

"Healthy" waist may be a bit bigger for black women....When I saw this Reuters story my first thought was one of intense skepticism (full disclosure — I am a black woman).

Allow me to give a brief explainer on all things fat-related:

  • Waistline circumference measures the amount of fat around one's abdomen. High levels of fat around the abdomen increase the risk of type 2 diabetes, hypertension and heart disease. Women with waist sizes above 35 inches and men with waist sizes above 40 inches are considered to be abdominally obese.
  • Non-Hispanic black women have higher rates of abdominal obesity than Non-Hispanic white women.
  • Body Mass Index (BMI) measures the amount of body fat relative to a person's weight and height, and is typically used to diagnose whether someone is obese. African-American women have the highest rates of obesity and, in general, being overweight, in the U.S.

So you can imagine my cynicism after reading that a new study finds that the BMI threshold for black women in the study was 32.6 — the highest BMI among blacks and whites of both genders in the study — while the threshold for white women was 29.6.

Here's an excerpt of the study, which was published in the journal Obesity:

Several studies that have included both AA [African-American] and white women have shown a racial difference in the relationship between BMI and mortality. In these studies, a significant relationship was found for white women, but the association was much weaker or nonexistent in African-American women. The weighted evidence suggests that the relationship between BMI and mortality may be less strong in AA than white women. The degree to which racial differences in the relationship between BMI and mortality may be explained by differences in the association between BMI and adiposity or risk factors is not known.

Regardless of my skepticism of the study's findings, the issue of obesity itself remains unchanged, says Dr. Paula Johnson, Chief of the Division of Women’s Health at Brigham & Women’s Hospital, and Executive Director for the Connors Center for Women’s Health and Gender Biology.

"We still have an absolute epidemic of obesity in our country...certain populations of women, including black women, are at very high risk and have significantly higher rates," Johnson said. "We need to recalculate those rates if in fact we see that these findings are accurate and can be replicated."

The need for accuracy when measuring BMI, waist circumference and the like is significant — even misdiagnosing a patient a couple of points too high could put them in the "cutoff" category, "for being eligible for maybe certain types of life insurance," Dr. Johnson said.

"So I think it's important that we get it right because you don't want to penalize [women] in that zone between 30 and 33, in terms of BMI, who should not be penalized."

One interesting thing to note about accurate measurements: Dr. Johnson said that taking these measurements, especially height, is not "uniformly" being done accurately (this is important because height is a factor in BMI calculations), and that in many practices, taking waist circumference measurements is not commonly done.

Back to the study. How much does race play into health care? In summing up the study, the doctors involved made an interesting point:

These results highlight the need to clarify racial differences in both the relative and absolute risk of disease, which is important to determine the need for ethnic-specific clinical guidelines.

"I think it’s yet again an important indication that sex and race and ethnicity should really be rigorously included in research as very significant variables," Dr. Johnson said.

The 1993 NIH revitalization ACT made these inclusions a federal law (yes, that's right, 1993 — only 17 years ago) in clinical research funded by the NIH, but, according to Dr. Johnson, many studies today still don't include enough minority participants. Oftentimes this shortage is due to money — the more participants, the larger the study, and the more rigorous the search for participants, the more expensive it is to fund the study.

“We still are a long way away from the majority of studies, when appropriate, including enough minorities to analyze the data in a meaningful way by sex and race groups, and we have a very long way to go,” she said.

In a world where paying attention to racial differences is taboo, health care may be one instance where it does matter if you're black or white.

This program aired on February 18, 2011. The audio for this program is not available.


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