Should People Considered ‘Skinny Fat’ Be Screened for Diabetes?
Research suggests body fat percentage may be a better predictor of type 2 diabetes than BMI, the commonly used measurement for health risk.
By Becky Upham
Don't Miss This
Sign Up for OurLiving with DiabetesNewsletter
Thanks for signing up!You might also like these other newsletters:
April 26, 2019
A new study suggests that healthcare providers who are conducting diabetes screenings according to high body mass index (BMI) alone may be missing a chunk of the normal-weight population that could actually be at a higher risk of the disease.
The research, published in April 2019 in the journal BMJ Open, found that individuals with a normal BMI but a high body fat percentage (a group popularly described as “skinny fat”) were more likely to have prediabetes or type 2 diabetes than people with a BMI that is considered overweight but who have a lower percentage of body fat.
To draw their results, researchers from the University of Florida (UF) used information from a 1999–2006 National Health and Nutrition Survey, the most recent national health data available that includes whole-body DXA measurement. This technology uses a whole-body dual-energy X-ray and is considered the gold standard to calculate body fat.
RELATED:Why BMI Is Flawed and the History Behind How the Scale Came to Define Obesity
BMI vs. Body Fat: Which Is a Better Predictor of Type 2 Diabetes?
A common way to measure BMI is by dividing a person’s weight in kilograms by his or her height in meters, and dividing again by height. The formula works for both men and women. The Centers for Disease Control and Prevention (CDC) divides BMI into four categories: underweight, normal, overweight, and obese. According to the National Institutes of Health, a BMI of under 18.5 is underweight, a BMI between 18.5 and 24.9 is normal, a BMI between 25 and 29.9 is overweight, and a BMI of 30 or more is obese.
Previous guidelines from the American Diabetes Association recommend screening for diabetes in the general population in people with a BMI that is 25 or over, and in the Asian American population by 23 or higher.
The CDC currently does not offer universally accepted guidelines regarding body fat, so the researchers used guidelines from American Association of Clinical Endocrinologists and the American College of Endocrinology, which classify 25 percent and above as high body fat for men, and 35 percent and above as high body fat for women.
The research focused on 6,355 adults ages 40 and over who had never been diagnosed with diabetes. This representative group was then divided into four subgroups: 1) normal weight with normal body fat percentage, 2) normal weight with high body fat percentage, 3) overweight with normal body fat percentage, and 4) overweight with high body fat percentage.
Thirteen and a half percent of people with a normal-range BMI and high body fat met the criteria for prediabetes or diabetes, compared with 10.5 percent of people with an overweight BMI, but lower body fat.
“Typically, normal BMI has been perceived as healthy, so people with normal BMI have been neglected in several preventive care guidelines,” says lead investigator Ara Jo, PhD, a clinical assistant professor in the department of health services research, management and policy at the UF College of Public Health and Health Professions in Gainesville, Florida. “Yet, normal BMI does not necessarily mean healthy body composition.” Dr. Jo notes that she was particularly surprised that more than 64 percent of the normal-BMI population had a higher percentage of body fat and showed higher risk of abnormal glucose compared with the population defined as overweight by their BMI.
RELATED:Can Thin People Get Type 2 Diabetes?
How the Study Findings May Affect Diabetes Screenings Based on BMI
Jo speculates that this study could undercut the value of using BMI measurement alone to determine health risk. “Body weight is an easy and important proxy for predicting chronic disease,” she says, but it doesn’t tell the whole story. This line of thinking not only may prevent normal-weight people from receiving helpful health screenings, but it could also contribute to stigma against people with a high BMI, Jo adds.
Fatima Cody Stanford, MD, an obesity and medicine physician at Massachusetts General Hospital in Boston, who was not involved in this research, says the study supports what researchers and clinicians have long known: BMI in and of itself doesn’t provide sufficient information about an individual’s cardiometabolic health. “BMI is a crude measure to help sort persons out who might need further intervention in regard to their weight. I don’t think it should be a standalone tool,” she says, adding that this measurement is used not just in the United States but worldwide. “The World Health Organization utilizes the BMI guidelines, but there are nuances, such as different cutoffs for certain races and ethnicities,” she says.
RELATED:What Causes Obesity Goes Way Beyond Just What’s on Your Plate
“BMI just takes into account height and weight; it doesn’t take into account muscle mass and it doesn’t take into account one [of] the things that is most important, which is this idea of central adiposity, or weight that’s carried in the midsection. This weight tends to be more visceral, which means that it surrounds the organs — when that fat is around organs, it precludes really great health as opposed to subcutaneous fat, which is less deleterious,” says Dr. Stanford.
People don’t necessarily need a high-tech imaging machine to find out if their risk for diabetes or heart disease may be higher — a simple measuring tape could do the trick. “For each patient I screen, I utilize BMI, but I also measure waist circumference as an initial screening to capture where a patient’s weight is distributed,” says Cody Stanford. “If a female has a waist circumference of greater than 35 inches or if a male has a waist circumference of greater than 40 inches, that portends to more metabolic issues, such as type 2 diabetes,” she says, pointing out that men should measure their waist circumference at belly button level, not at the waistline of pants.
Video: Jade and Julie compare diets
Taylor Swift Just Topped Maxim’s Hot 100 List—and Looks Amazing on theCover
How to Understand Virgo Man
How to Tell if You Have Reyes Syndrome
Christmas Card Etiquette Rules Only Old Schoolers Will Know
A Sparkly Silicon Beauty Blender Is What You Need Right Now
How to Save on Postage for Your Wedding Invitations
Trump 100 billion tax cut through capital gains inflation index plan
Cereal Bar Hay Bales
FDA Approves First Marijuana-Based Drug
Medium Chain Triglycerides
How to Handle Intimidation
How to Choose Fall Wedding Decorations
Louise Roe on How to Upgrade YourWardrobe