People risk developing type 2 diabetes if they can no longer fit into the jeans they were wearing when they were 21, according to one of the world’s leading experts on the disease.
And if people discovered they could no longer fit into the same-sized trousers then they were “carrying too much fat”, Prof Roy Taylor, from Newcastle University, said.
Taylor was presenting data at the European Association for the Study of Diabetes’ annual conference on an early study that found that people of normal weight with type 2 diabetes could “achieve remission” by losing weight.
Eight in 12 people managed to “get rid” of their condition by losing 10 to 15% of their body weight.
The participants, who had type 2 diabetes despite having a “normal” body mass index (BMI), managed to cut the levels of fat in the liver and pancreas, and the activity of the insulin-producing cells in the pancreas was deemed to be restored.
Taylor, the principle investigator, said: “Doctors tend to assume that type 2 diabetes has a different cause in those who are not overweight. What we’ve shown is that if those of normal weight lose 10 to 15% of their weight, they have a very good chance of getting rid of their diabetes.”
The participants, who had an average BMI of 24.5, followed a weight-loss programme that included a low-calorie liquid diet for two weeks – where each day they were consuming only 800 calories a day through soups and shakes.
They completed three rounds of this programme until they lost 10 to 15% of their body weight.
After weight loss was achieved, scans showed reductions in the fat in the liver and eight of the 12 participants had their type 2 diabetes go into remission, which was defined as having blood sugar levels under control and patients no longer needing any medication.
Taylor said the results, while preliminary, “demonstrate very clearly that diabetes is not caused by obesity but by being too heavy for your own body”.
He added: “As a rule of thumb, your waist size should be the same now as when you were 21. 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.”
Dr Lucy Chambers, the head of research communications at Diabetes UK, which funded the study, said she welcomed the findings but cautioned that they were early, with full results expected in 2022.
This article was amended on 29 September 2021 to restore the full comment made by Professor Roy Taylor concerning trouser size; it clarifies a “rule of thumb” relating to waist circumference.