Is There a Link Between Obesity and Type 2 Diabetes?

Obesity is a risk factor for type 2 diabetes, but it doesn’t guarantee someone will develop the condition. Preventing and managing obesity and type 2 diabetes requires open discussions that avoid stigmatizing people with larger bodies.

In our interview with Lorena Drago, RDN, CDCES, we explore the relationship between obesity and type 2 diabetes.

Hi Lorena, thank you for joining us! Could you explain what obesity is and how it’s clinically diagnosed?

Ongoing research reveals that obesity is far more complex than it seems, with much still to be understood. 

Obesity is a chronic and progressive disease, very similar to high blood pressure (aka hypertension), and is about more than just diet and physical activity. 

Body Mass Index (BMI) is a basic calculation based on your height and weight. You can calculate yours here.

• If a person has a body mass index value between 25 and 29.9, they are considered overweight. 
• For obesity, BMI values range from 30 to 39.9. 
• Severe obesity is defined as a BMI of 40 or higher.

Some people with a BMI of 28 or 30 may not be considered obese. For example, if you have more muscle mass, you might weigh more without actually being obese.

We know that there is a link between obesity and type 2 diabetes, but we also know that it is not the only cause or risk factor for developing type 2 diabetes. How are they linked?

Well, it begs the question: what came first, the egg or the chicken? While not everyone who is overweight or obese develops type 2 diabetes, 90% of people with type 2 diabetes are overweight or obese.

Several factors may explain the link between obesity and type 2 diabetes, including:

• Insulin Resistance
• Inflammation
• Organ response to belly fat (visceral adipose tissue) 
• Genetics 
• Lifestyle

These factors work together to increase the risk of developing type 2 diabetes in people who live with obesity.

The Diabetes Prevention Program (DPP) showed that people with prediabetes who lost 5-7% of their weight and got 150 minutes of exercise a week reduced their risk of developing type 2 diabetes by 60% over three years.

The body responds positively to these interventions. A similar result was seen in people with type 2 diabetes who lost 10-15% of their initial body weight.

The Look AHEAD (Action for Health in Diabetes) trial, with 5,000 participants, also showed that weight loss helped reduce A1C levels.

If a person living with type 2 diabetes loses weight, can they normalize their blood glucose or reverse the diagnosis?

Clinical trials show us that weight loss does not necessarily send type 2 diabetes into remission. 

In 2018, the Diabetes Remission Clinical Trial (DiRECT) was designed to see if losing weight could help people with type 2 diabetes get rid of their condition—at least temporarily.

Here are the key findings from DiRECT in 2018:

• Significant Weight Loss: Participants in the intervention group lost an average of 22 pounds over 12 months.
• Diabetes Remission: 46% of participants in the intervention group achieved remission of type 2 diabetes at 12 months.
• Sustained Weight Loss: Weight loss was maintained at 12 months—with participants losing an average of 17 pounds
• Improved Beta-Cell Function: Participants who went into remission had better beta-cell function, meaning their bodies made more insulin.
• Reduction in Medication: Many participants were able to reduce or stop their diabetes medications.
• Health Benefits: Participants experienced improvements in blood pressure, cholesterol levels, and overall well-being.

The Bottom Line

Obesity is a key risk factor for type 2 diabetes. 

Managing obesity with weight loss, exercise, and healthy habits can reduce the risk of type 2 diabetes and improve overall health, including blood sugar control.

Remember—obesity doesn’t always lead to type 2 diabetes. It’s a complex issue that requires more understanding and compassionate care than many realize.

Taking small steps toward healthier habits can make a big difference, and it’s always okay to reach out for support along the way.

This content was made possible with support from Lilly, an active partner of Beyond Type 1 at the time of publication.

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