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How to beat the blood sugar

Dr Michael Mosley, the 5:2 diet creator, is busting more myths about weight loss. He’s tackling type 2 diabetes – a global health crisis – and says rather than relying on drugs, the crash diet is the secret to restoring health.

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It came as a shock to Dr Michael Mosley when he was told his blood sugar measured in the diabetic range. The British author and broadcaster had visited his doctor with a minor skin complaint and while he was there had routine blood tests. To receive a call saying the results showed he needed to start taking medication for type 2 diabetes wasn’t expected, particularly since Mosley, in his mid-fifties at the time, seemed reasonably fit.

“I had some dodgy bathroom scales that were under-reading but I reckon I weighed about 85kg so at 5ft 11in [1.80m] I was only mildly overweight,” he says.

“I didn’t look fat, but it turned out that I was a TOFI – thin on the outside and fat on the inside.”

While making a documentary for the BBC, Mosley had an MRI scan that showed he was carrying the most dangerous weight of all – abdominal fat, lots of it, around his kidneys, liver and pancreas. Hence the bad-news blood tests.

“In retrospect I should have been more aware,” he admits. “My father developed diabetes in his early fifties and went on to have complications such as heart failure and dementia. He died at 74 and at his funeral his friends all said how like him I was, but I still didn’t make the connection or think to have my blood sugar tested.”

Mosley didn’t follow his GP’s advice to take medication. Instead he lost 8kg on a programme of intermittent fasting – a technique he later successfully marketed as the 5:2 diet or the Fast Diet, and his blood-sugar level improved as a result. That was four years ago and it has held steady since.

Intrigued, he wondered why the medical community wasn’t discussing this and started looking around to see if anyone was doing research on the subject. He came across Roy Taylor, professor of medicine and metabolism at New­castle University. Taylor’s work now forms the foundation of Mosley’s latest book, The 8-Week Blood Sugar Diet, in which he courts controversy with his claim that the best way to reverse or prevent type 2 diabetes is with rapid weight loss achieved through a very low-calorie way of eating – essentially a crash diet.

“I was astonished too,” he says. “It flew in the face of everything I’d been told.” He is aware crash diets are much maligned and that accepted weight-loss wisdom is slow and steady is best. Nevertheless, he is convinced that an 800-calorie a day diet for up to eight weeks is a far better solution to the global diabetes epidemic than any medication.

And type 2 diabetes is an epidemic – there is no controversy about that. The Ministry of Health reports it is New Zealand’s largest and fastest-growing health issue. More than 250,000 New Zealanders have diabetes and a quarter of the population is estimated to be in the pre-diabetic stage, although many aren’t aware of it.

Once dubbed adult-onset diabetes, type 2 is now being seen in children, particularly in Maori and Pasifika families.

The conventional advice to sufferers is that they will always have the disease and it can be controlled by diet initially, then medication, and that it may eventually require insulin injections.

“They may as well put up a sign that says, ‘abandon hope all ye who enter here’,” says Mosley. “People with diabetes are told they’re doomed. It makes me sad and slightly angry.”

Photo/Getty Images Photo/Getty Images


Mosley wants to transform that way of thinking and offer hope of remission. He points to the science that inspired Taylor’s work, which showed that obese people with diabetes who had bariatric (gastric bypass) surgery had their blood-sugar levels return to normal within days, with many able to come off their medication.

To see if he could replicate these results, Taylor ran a small clinical trial involving 11 people who’d had type 2 diabetes for up to four years. He mimicked the reduction of calorie intake that occurs after bariatric surgery by putting them on an extreme diet of 600 calories a day of liquid meal replacements and 200 calories of non-starchy vegetables for two months.

He chose motivated participants and gave them lots of support. All lost weight; and all reversed their diabetes. Three months later, seven remained free of it.

Taylor’s theory is that every individual has a personal fat threshold. In some people this is set high and in others surprisingly low. Once we cross it, the fat spills over and starts filling up the liver and pancreas.

“Then you’re in trouble,” says Mosley, “because the pancreas is no longer able to produce insulin.”

Insulin is what keeps blood-glucose levels in the normal range. Taylor’s thinking is that a low-calorie diet removes the fat clogging the pancreas and allows normal insulin secretion to be restored. He is not just shooting this stuff off the top of his head. Specialised MRI scans of the participants in his trial revealed fat levels in the pancreas had gone from elevated to normal (from about 8% to 6%).

Diabetes UK has now awarded the ­largest research grant – more than £2.4 million ($5.2 million) – in its 80-year history to Taylor and Professor Mike Lean at the University of Glasgow, to compare the long-term effects of this new approach to weight management with current diabetes care practice.

The study will run until October 2018, and although Mosley concedes it is still early days, he believes we can’t afford to sit around waiting for the results because the longer an individual is diabetic the less likely it is that weight loss will lead to reversal.

Professor Roy Taylor, and Professor Mike Lean, below, have been awarded the biggest grant in Diabetes UK history, to compare the long-term effects of the new approach to weight management to current diabetes care practice. The study will run until October 2018. Professor Roy Taylor, and Professor Mike Lean, below, have been awarded the biggest grant in Diabetes UK history, to compare the long-term effects of the new approach to weight management to current diabetes care practice. The study will run until October 2018.


In truth, it doesn’t matter how you drain fat from your organs – a gradual approach will get you there in the end so long as you stick to it. The trouble is, we don’t seem to be able to and, despite years of listening to the slow-and-steady advice, we are getting fatter.

“I’m proposing a solution that is science-based but radically different,” says Mosley, “and a lot of what I’m saying is not all that controversial, even if it sounds like that.”

There is other compelling evidence to back what Mosley calls the VLCD (very low-calorie diet). A 2013 review published in the New England Journal of Medicine, written by leading US obesity experts and entitled “Myths, Presumptions and Facts About Obesity”, reported that within weight-loss trials, more rapid and greater initial weight loss has been associated with lower body weight at the end of long-term follow-up. A 2014 study from the University of Melbourne affirms this. Researchers randomly assigned 200 obese adults to either a 12-week rapid weight-loss programme on a diet of fewer than 800 calories a day or to a 36-week gradual weight-loss programme where their normal daily intake was cut by 500 calories.

Nearly 81% of the rapid dieters lost 12.5% of their body weight compared to 50% of the graduals. And the dropout rate was lower in those who saw fast results. Parti­cipants were followed for another three years and although many did regain weight, the amounts were similar for both groups.

“Rapid weight loss has an awful reputation because of things done in the US,” concedes Mosley. He references one of the more notorious programmes, the Last Chance Diet promoted in the 1970s by an osteopath called Robert Linn who advocated losing fat fast using his high-protein drink, Prolinn. There were reports of a number of sudden deaths and it seemed the diet was causing malnutrition.

Professor Mike Lean. Professor Mike Lean.


Mosley says it is possible to cut calories right down and still be adequately nourished, and he is adding his voice to those calling for a rethink on the recommended balance of fat and carbohydrates in our diets.

The advice to go low-fat stems from the work of a US physiologist, Ancel Keys, in the 1950s, which was then promoted by the American Heart Association, which advocated plenty of carbs instead. By the 1980s this way of eating had really taken hold.

“At the same time there was an explosion in obesity,” says Mosley. “That is striking. It surely can’t be a coincidence. As any farmer knows, to fatten livestock you give them a lot of carbs. In retrospect it was insane but it continues to be pushed.

“I still hear dietitians banging on about low-fat diets. I find it completely astonishing. The wider message of my book is that we’ve ignored one of the most powerful predictors of health. We’ve become obsessed with fat and ignored the dangers posed by sugary carbs. People are beginning to recog­nise this but extraordinarily slowly given the data.”

Easily digestible, starchy carbs such as bread, pasta and potatoes rapidly turn into sugar when they enter the body. One way of tracking how fast a food will spike blood sugar is to check its Glycaemic Index.

Mosley advocates a simpler approach, cutting out these refined carbs altogether and replacing them with beans, lentils, chickpeas, quinoa and buckwheat, combined with lots of vegetables, the less-sweet fruits, quality proteins and fats from olive oil, nuts, yoghurt, butter, cheese and coconut. He dubs this the M-Plan, since mostly it is a low-carb version of the traditional Mediterranean diet. The recipes in the back of his book, courtesy of dietitian and nutritionist Sarah Schenker, include on-trend carb replacements such as cauliflower rice and spiralised zucchini noodles.

So what of the 5:2 diet and intermittent fasting that until now have been the approach Mosley has energetically recommended? He hasn’t abandoned that and sees it as a gentler option for diabetics and pre-diabetics who struggle with a very low-calorie diet.

“You won’t lose weight as fast as you would if you stuck to 800 calories a day but it can be more effective than conventional dieting.”

The Newcastle study used meal replacement drinks, but Mosley says it is preferable to stick to real food and to continue with this style of eating once out of the rapid weight-loss phase (Taylor advises consuming two-thirds of what you used to eat, whether or not you are exercising more).

There are some forms of diabetes that a very low-calorie diet won’t influence. Anyone who is frail, has a low BMI or a ­history of eating disorders shouldn’t embark on one. Checking with a doctor is advised if you are on medication for blood pressure, or on warfarin, insulin, diabetic medication other than metformin, are pregnant, breastfeeding or have a significant medical condition. Otherwise, says Mosley, don’t hold back. Even if you are still in the pre-diabetic range there is evidence from a trial from the National Institutes of Health in the US that losing a small amount of weight can sharply reduce the chances of developing diabetes. Metformin, the most commonly prescribed drug, was also effective, but markedly less so, particularly in people aged 45 and older.

Michael Mosley with journalist Mimi Spencer, with whom he wrote the best-selling The Fast Diet. Michael Mosley with journalist Mimi Spencer, with whom he wrote the best-selling The Fast Diet.


Mosley is critical of doctors who choose to write a prescription rather than give ­dietary or exercise advice even though there is overwhelming proof of the importance of lifestyle.

“Doctors go into the job because they want to make people better, they just don’t know how to do it,” he says. “They get no dietary training. When I was at medical school we received none and my son, who is there now, receives none.

“They are taught about human anatomy and how to dispense drugs. But this is a lifestyle catastrophe and drugs are not the answer.”

Even with medication, diabetes can wipe years off your life. Metformin has limited benefits and may not reduce the risks of heart attack or improve life expectancy, according to a 2011 French paper published in the British Medical Journal.

“We’re told people want a pill,” says Mosley. “That’s based on the belief they won’t want to do it [diet], that they are weak and greedy. I think that’s mistaken. But if they don’t know how serious it is, if they aren’t presented with the information that will help them to change …”

Among the case histories in his new book is that of the Whitington brothers whose father Geoff had fallen into diabetes-related depression and was facing the prospect of foot amputation. Ian Whitington is a film-maker and he told his father he wanted to include him in a documentary about diabetes. The result, called Fixing Dad, shows how rapid weight loss turned Geoff’s life and health around.

For Mosley, there is a lot of personal sadness attached to this success story.

“If I’d known what I know now I could have saved my own father. I gave him the wrong advice, which was what everyone was saying at the time. It was a horrible mistake. He could have seen his grandchildren grow up and been spared a lot of suffering. I say this with the wisdom of hindsight; possibly he wouldn’t have listened.”

Mosley is hoping people will listen. His GP wife Clare certainly has. “She has started putting a lot of the things I talk about into practice,” he says. “Initially, her ­colleagues were sceptical but they’ve seen huge benefits.”

As he knows from personal experience, not everyone heading into the diabetic range is going to seem obviously overweight, so he suggests regular blood-sugar testing.

“One of the best predictors of future health is your fasting-glucose level,” he points out. “It’s a more powerful predictor than cholesterol is. Yet it’s cholesterol we are all told to worry about.”

Mosley, who will be in New Zealand in March to talk about his latest work, is passionate about his message that a very low-calorie diet combined with exercise is a quick-fix for a global public-health crisis.

“I want this to be a revolution,” he says.

Take the test

Are you at risk of type 2 diabetes?

1. Do you have a diabetic parent or ­sibling? 1 point
2. Are you being treated for ­hypertension? 1 point
3. Are you from a non-white ethnic background? 1 point
4. Are you aged 50 to 59? 1 point
5. Are you over 60? 2 points
6. Is your waist more than 89cm but less than 107cm? 1 point
7. Is your waist more than 107cm? ­(Measure your waist around the belly button, not your trouser size) 2 points
8. Is your Body Mass Index 25-30? 1 point
9. Is your BMI 31-35? 2 points
10. Is your BMI more than 35? 3 points

(For your BMI score see here, which will calculate it for you.)

Add up your total score

Less than 3 points: You have a low risk of becoming type 2 diabetic in the next 10 years.

3-5 points: You have a ­moderate risk of becoming diabetic and as you get older this risk will increase. Check your blood sugars and consider making lifestyle changes so you can reduce your risk.

More than 5 points: You are at high risk of becoming ­diabetic. You should definitely have your blood sugars tested and aim for lifestyle changes, such as significant weight loss and increased activity.

From The 8-Week Blood Sugar Diet, (Simon & Schuster)

Fixing Dad. Fixing Dad.

Fixing Dad

Brothers Anthony and Ian Whitington (Ian is at left in the top photo) with their diabetic father Geoff who is profiled in Michael Mosley’s The 8-Week  Blood Sugar Diet.  Geoff has starred in a documentary Fixing Dad, made by film-maker Ian. Geoff’s secret consumption of takeaways led to type 2 diabetes and 11 years after his diagnosis his ulcerated foot was in danger of amputation, he had neuropathy and was becoming reclusive. “The father we knew had disappeared in a fog of depression, embarrassment, lack of confidence and pain,” says Anthony.  Geoff’s sons researched the evidence on rapid weight loss for diabetics and put him on a low-calorie diet and asked him to take a photo of every meal on his phone. Exercise and weight loss (38kg) turned their father’s life around and reversed his diabetes.  “He is totally different now,” says Anthony. “He has ­self-belief. The man who spent the last decade at home, now goes into companies and tells staff how to fix themselves.”  (Fixing Dad is available as pay per view on Vimeo.)

Photo/Getty Images Photo/Getty Images

Carbs v low fat

•  In Italy, pizza, pasta and rice may be on the menu frequently but starchy, easily digested carbs don’t form a part of the Med-style diet that Mosley recommends for diabetes prevention. They are to be avoided – along with sugary treats, commercial breakfast cereals and too many sweet tropical fruits such as mango, pineapple and banana.

  Instead, lots of vegetables, high-quality proteins, olive oil, nuts, seeds, eggs, full-fat yoghurt, beans, lentils, quinoa and buckwheat are the stars.

•  The evidence in favour of this way of eating includes the PrediMed (Prevention with Mediterranean Diet) study. ­Spanish researchers allocated 7400 people to a Mediterranean diet or a low-fat diet. Those eating low-fat were encouraged to consume lots of starchy carbs. The Mediterranean eaters were allowed nuts, olive oil, dark chocolate and even the odd glass of red wine with their evening meal.

•  The results showed that the Mediterranean eaters were 30% less likely to die of a heart attack or stroke and the diet had a favourable effect on other health problems including insulin resistance. Subsequent studies have suggested this sort of diet can also reduce the risk of breast cancer and cognitive decline.

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