Could the future of type-2 diabetes treatment be prescription diets?

In the future doctors could prescribe low calorie diets to reverse type-2 diabetes, not tablets and surgery, according to one scientist conducting a 5-year study on such a strategy.

Currently the UK’s National Health Service (NHS) spends about £75m (€97.93m) a year on drugs to help regulate the blood glucose levels of people with type-2 diabetes as normal as possible, not to mention the cost of expensive, invasive and potentially risky surgical operations such as gastric banding and bypasses to help patients lose weight rapidly.

But professor Roy Taylor of Newcastle University and Professor Mike Lean of the University of Glasgow hope their 5-year study, the Diabetes Remission Clinical Trial (DiRECT), will help validate a cheaper solution of a 600 calories a day liquid diet that could reverse the abnormalities underlying type-2 diabetes - beta cell failure and insulin resistance – permanently.

The pair, who have known each other since working together as first-year doctors in Edinburgh, were awarded a £2.4m (€3.13m) grant by Diabetes UK in 2013, the biggest figure in the charity's 80-year history. The money will be put towards the long-term study, which started last autumn and seeks to confirm if promising results recorded with 11 people over eight weeks in 2011 could be lasting.

Roy-Taylor-3.jpg
Professor Roy Taylor. Photo: Diabetes UK. 

Speaking with NutraIngredients, professor Taylor said: “We want to talk about this and publicise this interesting area of work but at the same time we don't want to give the impression that it's a no brainer that the weight loss approach will be better. We really have to wait to find out.”

“We might get the brilliant results with weight loss we’ve already observed, but then the people who lose the weight but then just can’t maintain the weight may end up being worse off.”

Taylor said the cost impact for the NHS could be huge – calculating that even if one in five people signed up to such a diet, the yearly saving could be around £14m (€18.27m).

“But also the value to the individuals of no longer having this terrible label of diabetes – paying more for their holiday insurance, regular hospital visits, taking time off work and having to take all the tablets. So it’s really quite an important business to try and get right.”

An extreme diet for an extreme condition

Taylor said whilst the diet was ‘extreme’, compared to the time off work needed for surgery and the associated risks of that it was relatively less invasive. “Yes it’s extreme but we shouldn’t forget we’re dealing with an absolute medical emergency here. These people are heading towards strokes and amputations and all sorts of nasties.”

The recommended average daily calorie intake for men is 2,500 and 2,000 for women. This experiment diet contains a daily count of 600 calories made up of sugars, fats and all the minerals needed. EFSA recently issued an opinion on what a low calorie diet should consist of. 

He said the diet wasn’t a “magic recipe” but simply provided enough energy for the body to “tick over” and spurred it into burning up excess fat supplies.

Yet he said the current study model would be as close to "real life" as possible, with flexibility in the time taken to achieve the target weight loss built in, allowing an extension beyond the initial 12 weeks.

Some participants who had achieved the base weight loss by the point even chose to continue with the weight loss programme, he said. 

“So the people have spoken as it were, or at least are speaking, and we’re finding that far from wanting to come off this diet that observers view as 'extreme', people who want to achieve their goals are actually sticking with it for longer than they originally signed up to.”

Long term changes

After the three-month intervention, participants must go back to eating normal foods stuff. “The clever bit is not the intervention, it’s getting people back eating – but eating much less than they used to because to keep the weight off they will have to drop their calorie intake by about a third.”

He said there was a huge behavioural element to this follow up – with very specific guidance after the three months for the quantity of food.

“Yes we are talking about bringing about long term changes but in order to do that we’ve got to have a long term change in this terribly dysfunctional pattern of eating we’ve slipped into in this country.”

He said as a population we had “lost it” with regards to what we see as a healthy weight – with type 2 diabetes not actually being a problem of obesity per say but one of the overweight and overfed and our perceptions of normality around that.