The American Diabetes Association Is Reevaluating BMI for Weight Management

Fact checked by Nick Blackmer

Key Takeaways

• In its new 2024 guidelines, the American Diabetes Association (ADA) says that in addition to BMI, other measurements of fat distribution should be considered when it comes to treating patients with type 2 diabetes.

• The ADA also says that weight loss should be a primary goal for people with type 2 diabetes, echoing its previous recommendation.

• Weight loss of more than 10% of body weight is associated with better health outcomes for people with type 2 diabetes, including the remission of the disease.

The American Diabetes Association (ADA) recently published its updated guidelines for 2024—including its new recommendations around body mass index, or BMI, and weight management for type 2 diabetes.

Part of the new guidelines, called Standards of Care in Diabetes, include the recommendation that healthcare providers use other measurements of body fat distribution, such as waist circumference, waist-to-hip ratio, and/or waist-to-height ratio in tandem with BMI. In its 2023 guidelines, the ADA focused on BMI.

BMI has long been a metric used to assess risk related to type 2 diabetes. That’s because obesity can increase the chance of developing the disease, as well as further disease progression.

Many health experts, however, believe that BMI is an incomplete way to determine someone’s health, as it does not take into consideration body composition, such as muscle mass or where fat is stored on the body, as well as ethnicity, age, and race.

“These other measures, like waist-to-hip ratio, give a fuller view of the state of obesity in the individual and can guide therapy,” Robert Gabbay, MD, PhD, chief scientific and medical officer for the American Diabetes Association, told Verywell. “We know that a high waist circumference or waist-to-hip ratio is an additional risk factor leading to worse outcomes.”

Takeaway

BMI is a dated, flawed measure. It does not take into account factors such as body composition, ethnicity, sex, race, and age. Even though it is a biased measure, BMI is still widely used in the medical community because it’s an inexpensive and quick way to analyze a person’s potential health status and outcomes.

Related: BMI Can’t Predict Diabetes Risk for Asian Americans. What Else Might Work?

Are New Measurements to Supplement BMI Realistic?

The ADA recommends healthcare providers measure waist circumference, waist-to-hip ratio, and/or waist-to-height ratio alongside BMI.

BMI: BMI is a measurement based on height and weight. BMI is calculated by dividing their weight in kilograms by their height in meters squared (kg/m²). The ADA points out that it is often calculated automatically by most electronic medical records.

“BMI is convenient, so it’s a great epidemiologic tool used for population screening and it can be flagged on electronic health records,” Andrew Kraftson, MD, a clinical associate professor at the University of Michigan who specializes in endocrinology and diabetes, told Verywell Health. “But there are tons of papers that talk about how waist circumference and waist-to-hip would also be helpful.”

Waist circumference: Waist circumference, on the other hand, is a measurement of the waist that helps measure fat around the belly. It is a helpful measurement because higher weight circumference scores, which show excessive abdominal fat, are associated with type 2 diabetes.

The CDC says you have a higher risk of developing obesity-related conditions if you are a man with a waist circumference of more than 40 inches or a woman with a waist circumference greater than 35 inches.

Waist-to-hip ratio: Your waist-to-hip ratio can also be a predictor of type 2 diabetes. Another way of assessing abdominal obesity, this measurement is calculated by measuring both your waist and hip circumferences, then dividing the waist measurement by the hip measurement.

To get a sense of ideal waist-to-hip ratios, a woman’s ratio should be less than 0.85, and a man’s should be less than 0.9.

Related: Researchers Say Waist-to-Hip Ratio Should Replace BMI—Here’s Why

Waist-to-height ratio: Likewise, higher waist-to-height ratios can be predictors of obesity and/or type 2 diabetes. A person’s waist-to-height ratio can be calculated by dividing their waist circumference by their height.

According to research published in Plos One, a waist-to-height ratio greater than 0.53 in men and 0.54 in women is associated with obesity and disease.

Kraftson explained that there is some hesitancy to actually use additional measurements beyond BMI in clinical settings. He said healthcare providers need to be trained on exactly how to take such measurements, and patients might feel uncomfortable lifting their shirts or lowering their pants to have it done.

“There are these small—but significant—barriers,” Kraftson said.

ADA-Recommended Approaches to Weight Loss

Another key recommendation from the ADA: For people with type 2 diabetes who have overweight or obesity, weight management and glycemic management should be primary goals.

In its recommendations, the ADA points out that losing 10% or more of body weight is associated with positive health benefits, including the possible remission of type 2 diabetes and improved long-term cardiovascular outcomes and mortality.

When it comes to weight loss interventions or tools, the ADA recommends, in this order:

• Nutrition, physical activity, and behavioral therapy

• Pharmacotherapy

• Medical devices

• Metabolic surgery

“Lifestyle changes are the primary therapy with effective nutrition and exercise. However, if these are not effective, one must consider medications like semaglutide or tirzepatide,” Gabbay said. “Metabolic surgery is another option when not meeting weight goals.”

Nutrition, physical activity, and behavioral therapy section: This includes interventions such as regular health counseling focusing on nutrition, exercise, and behavioral strategies that aim to help people burn an extra 500 to 750 calories per day.

Pharmacotherapy recommendations: The ADA says medications for comorbid conditions associated with weight gain should be minimized whenever possible. For people with overweight or obesity and type 2 diabetes, drugs that promote weight loss should be considered along with lifestyle changes.

The preferred medication is a glucagon-like peptide 1 receptor agonist (GLP-1) such as Ozempic (semaglutide) or a dual glucose-dependent insulinotropic polypeptide (GIP) agonist and GLP-1 agonist such as Mounjaro (tirzepatide).

Related: Can You Take Ozempic With Other Medications?

“The problem is that only about 10% of people are successful at losing 10% of their body weight and keeping it off for a year with lifestyle management alone,” John Buse, MD, PhD, an endocrinologist and professor at the University of North Carolina’s School of Medicine, told Verywell. Buse was formerly the president of the American Diabetes Association and a guideline writer.

“As these [weight loss and diabetes] drugs have evolved, they are so much more effective, and it’s frankly easier to achieve that kind of weight loss,” he said.

Medical devices: The ADA acknowledges that “gastric banding devices have fallen out of favor due to their limited long-term efficacy and high rate of complications.”

That said, the ADA includes an oral hydrogel (Plenity) that has been approved by the FDA for long-term use in people with a BMI of 25 kg/m² or greater “to simulate the space-occupying effect of implantable gastric balloons.”

Metabolic surgery: The ADA says that weight loss surgery could be considered for people with diabetes who have a BMI of greater than 30.0 kg/m² (for Asian Americans, the BMI measurement is 27.5 kg/m² or more) as a way to manage weight and blood sugar. People should be in otherwise good condition to be considered candidates for surgery.

Any surgery should be performed by specialists who have great experience managing obesity, diabetes, and gastrointestinal surgery, the ADA says.

Related: Weight Loss Drug vs. Bariatric Surgery: Which One Is Better?

The bottom line, said Buse, is that these ADA guidelines focus on weight loss and weight management because it can improve the health outcomes of people with obesity and type 2 diabetes.

“By focusing on weight loss, we’re basically dealing with the root cause [of type 2 diabetes] as opposed to giving someone medicines for their diabetes, medicines for their blood pressure, and extra medicines for their cholesterol,” Buse said.

What This Means For You

BMI is a helpful but not complete tool for assessing type 2 diabetes risk or managing progression of the disease. Other factors, such as waist circumference and waist-to-hip ratio, are also important measurements. In addition, weight loss should be a primary goal for people with type 2 diabetes and obesity in order to improve health outcomes.

Read the original article on Verywell Health.