While an estimated 38 million Americans have type 2 diabetes, the disease is increasingly being diagnosed among young adults. Without treatment, they face decades of high risk of complications such as heart disease and kidney failure.
A recent study published October 1 in The Lancet Regional Health – Americas examined whether a combination of intensive weight loss and structured exercise could put early-onset type 2 diabetes into remission.
The researchers recruited 96 adults aged 18 to 45 who had obesity and had been diagnosed with type 2 diabetes in the previous six years. The average age of the participants was around 38 years old and they had been living with diabetes for an average of just over two years. The small clinical trial was conducted in Canada and the United Kingdom.
To help understand the findings and what they mean for diabetes treatment, I spoke with CNN wellness expert Dr. Leana Wen. Wen is an emergency physician and clinical associate professor at George Washington University. She previously served as Baltimore’s health commissioner.
CNN: Why is early-onset type 2 diabetes of particular concern?
Dr. Leana Wen: Early-onset type 2 diabetes refers to diabetes diagnosed before the age of 45. It tends to progress more quickly than diabetes diagnosed later in life, with faster progression and a higher risk of complications.
A person diagnosed at age 30 could live with diabetes for decades. Over time, high blood sugar can damage blood vessels, nerves, kidneys and eyes. Young adults with type 2 diabetes also face an increased risk of cardiovascular disease and premature death.
Substantial weight loss can put type 2 diabetes into remission, previous research has shown, but most of those trials have focused on older people. In this study, researchers wanted to know if this approach could work in younger patients, whose disease may be more aggressive. The team also wanted to test whether adding supervised exercise that included strength training could preserve muscle during rapid weight loss.
CNN: What did the study reveal?
Magnifying glass: Participants were randomly assigned to either an intensive diet and exercise program or their usual medical care, meaning they continued treatment with their healthcare professional. After six months, 54% of participants in the intervention group achieved diabetes remission, compared to only 4% receiving usual care.
Remission was defined as a hemoglobin A1c level below 6.5%, the threshold for diagnosis of diabetes, without hypoglycemic treatment for at least three months. (Hemoglobin A1c reflects the average measurement of blood sugar over a period of time and is a standard measure of diabetes diagnosis and treatment effectiveness.)
Participants in the intervention group also saw a substantial reduction in their body fat, losing about 16.5 pounds (7.5 kilograms) more than those receiving usual care. They also improved their cardiorespiratory fitness, demonstrating lower resting heart rates and improved exercise capacity.
During the first 12 weeks, members of the intervention group followed a supervised diet limiting calorie intake to 800 to 900 calories per day. For the first two weeks, these individuals consumed only meal replacements, then incorporated one regular meal per day while maintaining the calorie goal. Starting from the third week, participants in the intervention group attended two exercise sessions per week combining aerobic activity and resistance training using weights or exercise machines. They also performed a third session of aerobic exercise independently each week.
Over the past 12 weeks, participants gradually returned to a regular diet in an effort to maintain their weight loss. They continued to train independently and received ongoing support from dietitians and exercise specialists. Doctors monitored participants’ blood sugar and blood pressure throughout the program and adjusted medications if necessary.
Individuals seeking to replicate these results should understand the intensity of the intervention. The calorie restriction was severe and would be difficult for many people to follow safely. The exercise sessions were also demanding, and only 40% of participants met all criteria for adherence to the study program. The study took place in three specialist centers with regular support from doctors, dietitians and exercise specialists. We do not know whether similar results could be achieved in routine clinical practice, where people may not have access to these resources.
CNN: What should people with type 2 diabetes do if they want to try to reverse their diabetes through diet and exercise?
Magnifying glass: I would start with a conversation with your clinician to find out if remission is a realistic goal and what approach would be safe.
In particular, the low-calorie diet used in this study should not be attempted without very close medical supervision. People who take insulin or oral medications called sulfonylureas may develop dangerously low blood sugar levels when they significantly reduce their food intake. Clinicians may need to adjust these and other prescription medications if someone changes their calorie intake.
A less restrictive approach can nevertheless produce significant improvements. People can work with a dietitian to adopt a more nutritious diet, such as reducing sugary drinks and refined carbohydrates and prioritizing vegetables and foods high in fiber and protein.
For physical activity, try to stick to the recommended 150 minutes of moderate-intensity aerobic exercise per week. Add resistance training at least twice a week, with exercises targeting major muscle groups. Such changes can slow the progression of diabetes and prevent complications, even if they don’t reverse it.
CNN: Why did researchers focus on strength training?
Magnifying glass: Muscle plays a major role in regulating blood sugar. After eating, insulin helps move glucose from the bloodstream to muscle cells, where it can be used for energy or stored. In people with type 2 diabetes, insulin resistance makes this process less effective. Exercise helps muscles absorb glucose and improves their sensitivity to insulin, which can lead to better blood sugar regulation.
A consistent strength training routine has another important benefit: activity helps preserve muscle during weight loss. When people lose a lot of weight, they usually lose fat and muscle. This loss of muscle mass can pose particular problems for people with type 2 diabetes, who are already at increased risk of muscle deficiency and premature frailty. Preserving muscle can help maintain physical strength and metabolic health.
In this study, participants in the intervention group lost substantial amounts of fat without significantly greater loss of muscle mass than those receiving usual care. Another notable finding was that those in the intensive intervention group improved their grip strength by about 8%, suggesting that their muscles became stronger even as they lost weight. These findings support recommendations to integrate resistance training with aerobic exercise, especially when experiencing such rapid weight loss.
CNN: What are the other limitations of this study?
Magnifying glass: First, it was a relatively small trial – and the participants were all young adults with obesity and a relatively recent diagnosis of diabetes. In particular, the researchers excluded people receiving insulin treatment and those with certain medical complications, including cardiovascular disease and significant kidney disease. We cannot assume that the same remission rates would apply to older adults, people who have had diabetes for decades, or those with more advanced disease.
Second, the study compared a combined diet and exercise program to usual care, but did not include a group that followed the same diet without supervised exercise. We therefore cannot determine the additional benefit resulting from exercise, nor whether the remission rate would have been similar with dietary changes alone. Participants in the intervention group also received significantly more attention from healthcare professionals than those receiving usual care, which could have influenced their results.
Ultimately, the researchers followed the participants for only six months. Remission measured during this period does not mean that diabetes has been permanently reversed and cured. Blood sugar levels may rise again, especially if a person gains weight or their pancreas loses more of its ability to produce insulin. Longer-term research is needed to determine how many participants can maintain remission over several years.
Be inspired by a weekly summary on living well, made simple. Sign up for CNN’s Life, But Better newsletter for news and tools designed to improve your well-being.
Gn Health
