Type 2 diabetes is often associated with being overweight, but some people who are slim can also develop the disease.
These patients with a normal body mass index have “a very good chance” of going into remission by losing a substantial amount of weight — 10%-15% of what they weigh now, researchers said this week at the annual meeting of the European Association for the Study of Diabetes.
The early findings were a preview of a small study that’s expected to be finished next year. Two-thirds of the 12 participants went into remission, according to Roy Taylor, the principal investigator.
“Unlike those who are overweight, those who are of normal weight aren’t usually advised to lose weight before being given diabetes drugs and insulin,” said Taylor, a professor of medicine and metabolism at Newcastle University in the U.K., in a statement.
“This should be a wake-up call to doctors.”
Something else Taylor said is getting a lot of attention: As a rule of thumb, a person’s waist size should be the same now as when he or she was 21. So “if you can’t get into the same size trousers now, you are carrying too much fat and therefore at risk of developing Type 2 diabetes, even if you aren’t overweight,” he noted.
Dr. Robert Gabbay, chief scientific and medical officer for the American Diabetes Association, called it “maybe a little bit too simplistic” way of putting things. But generally, if a person’s waist circumference has increased a lot — to more than 35 inches for women or more than 40 inches for men — it does put them at risk for diabetes.
“Raising some level of concern about people’s body weight, certainly for most Americans, that's not necessarily a bad message,” Gabbay told TODAY.
Most people with Type 2 diabetes — a disease in which the body doesn't use insulin properly and blood sugar levels are too high — develop it in part because of obesity.
But about 10% of people with Type 2 diabetes are at a healthy BMI. The risk differs by race and ethnicity: the prevalence of the disease in this group was 5% in whites, 10% in Asians and American Indians/Alaskan Natives, 13% in Hispanics, 13.5% in Blacks and 18% in Hawaiians/Pacific Islanders, research has found.
The theory is that each person has a “personal fat threshold,” which — if exceeded — may cause fat to be stored in harmful places in the body and can lead to Type 2 diabetes, even if that person is slim. Internal fat around the pancreas and liver could be one of the reasons why people with a normal BMI can develop the disease, noted Diabetes UK, the charity that funded the study.
“It turns out that the fat in the abdominal cavity, around the organs, what we call visceral fat, is the fat that is most effective in causing insulin resistance,” Gabbay added.
As part of the new study, 12 men and women who had Type 2 diabetes and were of normal weight — with an average BMI of 24.5 — were asked to eat only 800 calories a day for two weeks. Their diet consisted mostly of low-calorie soups, shakes and non-starchy vegetables.
When those two weeks were over, they entered a maintenance phase for about a month, gradually returning to their regular eating regimen, but aiming to keep off the weight they lost, according to Diabetes UK.
They repeated this pattern up to three times until they had lost 10%-15% of their body weight.
Eight of the 12 participants achieved remission of their Type 2 diabetes, researchers reported. On average, the people in the study lost 18 pounds and reduced their body fat from 33% to 27%. Scans showed the amount of fat in their organs also fell.
It's too early to draw any conclusions from the results because it's preliminary data from a very small study, Gabbay noted. But this kind of weight loss early in the course of the disease can lead to remission based on previous studies done on people with obesity, he said. The challenge is being able to lose that much weight and keep it off.
The very low-calorie diet used in this study would be hard to stick to, said Kristin Kirkpatrick, the lead dietitian at Cleveland Clinic Wellness & Preventive Medicine in Cleveland, Ohio.
“My fear in this approach is this: Even though weight loss will surely occur short-term — and with it, most likely improvements in biomarkers — long-term, it is hard to sustain and weight may come back on,” she noted.
Allowing more calories and making them high quality could be more sustainable, Kirkpatrick added.
She also wasn’t a fan of worrying about fitting into jeans from one’s youth.
“We need to focus on what makes sense for better health in real time. Focusing on what is possible now may be better for long-term sustainability,” she said.