• We all have a level of fat our body can cope with, and exceeding it can trigger the development of type 2 diabetes, according to new research.
  • It also further supports the previous studies that suggest weight loss can reverse the metabolic condition, even in people with a Body Mass Index (BMI) within or just above the ‘normal’ range.
  • The study should help to break the stigma associated with type 2 diabetes and being overweight, showing that it is caused by storing too much fat inside the liver and pancreas rather than having a certain level of BMI.

We each have a ‘personal fat threshold’ that allows the development of type 2 diabetes if exceeded, according to research presented at the European Association for the Study of Diabetes (EASD) in Stockholm, Sweden.

A BMI over 30 has long been considered a risk factor for type 2 diabetes, with previous research demonstrating how intensive weight loss programmes can help people who are overweight or obese place their condition into remission.

Despite this, not everyone with type 2 is overweight, with around 15% of type 2 diagnoses in people with normal weight.

Led by Professor Roy Taylor and funded by Diabetes UK, the ReTune study (Reversal of Type 2 Diabetes upon Normalisation of Energy Intake in the Non-obese) used twenty men and women with type 2 who had a BMI at or just above the healthy range (below 27).

All participants followed a low-calorie (800 kcal per day) weight loss programme for a fortnight, including formula meal replacements such as low-cal soups and shakes. After this, the participants spent four to six weeks maintaining that weight loss while simultaneously reintroducing everyday foods back into their diet.

The weight loss and maintenance cycle was repeated three times until the participants had lost between 10-15% of their starting body weight. Researchers measured the fat around each participant’s pancreas and liver after each cycle using MRI scans. Through the scans, they could see whether an individual had gone into type 2 remission.

Fourteen or 70% of the participants went into type 2 remission, considered when HbA1c is less than 48mmol/mol for a minimum of six months and medication is no longer required to treat the condition. On average, the participants lost 7.7kg at remission or 10.7% of their initial weight.

The average BMI fell from 24.8 to 22.4, with total body fat falling from 32.1% to 27.7%.

The MRI Scans showed that fat levels inside the liver and pancreas had fallen substantially. Despite the average amount of fat in the liver being considered ‘unremarkable’ at 4.1%, this was around three times higher compared to healthy control groups of the same weight. The liver fat level was reduced through the programme to 1.4%, significantly closer to the healthy control level.

The fat in the pancreas fell from an average of 5.8% to 4.3%, with the activity of insulin-producing beta cells returning to normal.

Researchers involved in the study believe the results indicate that type 2 diabetes is caused by the same factors in normal-weight people as in those who are overweight or obese.

Doctors have previously assumed that there is a different cause for developing type 2 diabetes in people with a lower weight. Those individuals are typically prescribed diabetes medications rather than being advised to lose weight.

“But if they lost around 10% of their weight, they would have a very good chance of putting their type 2 diabetes into remission,” says Professor Roy Taylor, of Newcastle University, Newcastle, UK, the principal investigator on the trial.

It is hoped the research will help dispel the stigma surrounding type 2 diabetes diagnoses.

Professor Taylor continued: “This should help to remove some of the stigma that attaches to type 2 diabetes. It is clearly a condition which is not “caused” by being over any level of BMI but by storing a little too much fat inside liver and pancreas, whatever your weight.

“The results also support the personal fat threshold concept that anyone with type 2 diabetes has a little more fat on board than they individually can cope with.  This is determined by your genes. Each of us has a threshold level under which they can store fat safely and that this has little to do with BMI.

“If you develop type 2 diabetes, you simply have more fat inside your body than you can cope with, even if apparently slim.

“This excess fat spills into your liver and pancreas stopping normal function and causing type 2 diabetes. You only need an extra half gram of fat in the pancreas to prevent normal insulin production.”

Chris Askew OBE, Chief Executive of Diabetes UK, the charity which funded the study, added: “This game-changing study from Professor Taylor and his team advances our understanding of why type 2 diabetes develops, and what can be done to treat it.

“Our ambition is for as many people as possible to have the chance to put their type 2 diabetes into remission and live well for longer. The findings of the ReTUNE study potentially take us a significant step closer to achieving this goal by showing that remission isn’t only possible for people of certain body weights.”

This article is from an early release presented at the European Association for the Study of Diabetes (EASD) Annual Meeting in Stockholm, Sweden (19-23 Sept).

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