It might be a delicious, steaming bowl of spaghetti, or toast in the morning. Perhaps it’s a jacket potato for lunch, a couple of biscuits, or a banana and a glass of milk before bed. All are dietary staples enjoyed by millions of Britons.
But would you give them all up if it could ‘cure’ your type 2 diabetes, or prevent it from happening it the first place?
The answer might well be yes. Or at least, ‘I’ll give it a go.’ And some experts now advise just this, as part of a so-called low-carb diet.
It might be a delicious, steaming bowl of spaghetti, or toast in the morning. Perhaps it’s a jacket potato for lunch, a couple of biscuits, or a banana and a glass of milk before bed. All are dietary staples enjoyed by millions of Britons
For those facing a lifetime of medication, with the threat of illness, disability and an early death looming due to the blood sugar condition, the promise is persuasive – no matter if it means giving up a few of life’s pleasures.
In April, it was announced that one such diet plan, The Low Carb Program, had received approval to be prescribed by NHS GPs to people with type 2 diabetes and also those with pre-diabetes.
Half of a typical meal would be vegetables, while carbohydrates (favouring wholegrains, rather than ‘white’ carbs) and protein would each make up a quarter.
But the Program also gives advice to those who might want to cut carbs drastically – sometimes dubbed the ketogenic, or keto diet approach – to as little as 30g a day. That’s less than two medium slices of Hovis wholemeal bread.
Low-carb diets like the Atkins, Dukan and South Beach Diet have long been popular. Overall, there is a spectrum – officially, low carb can range from 130g a day to just 30g. And a slew of diet books and trendy websites now recommend the best way to beat diabetes and control blood sugar is by swapping pasta for strings of courgette, rice for finely shredded cauliflower, and bread for lettuce leaves. As for pudding, don’t even think about it.
It is restrictive, undoubtedly. Some might say the low end of the scale is extreme. But are such measures completely necessary? Not so, according to the experts who have devoted decades to researching blood sugar and its effect on the body. In fact, you can beat diabetes – or stop it before it strikes – with just a few tweaks.
Shed pounds… without missing the foods you love
At present, the only proven way to get diabetes under control is to shed pounds and slim down. And as long as you stick to a low-calorie diet, it doesn’t matter – within reason – whether or not those calories come from carbs.
This message underpins the exclusive recipes in today’s Mail on Sunday. They are designed to help you lose weight and improve your health – which does mean eating less. But it does not involve cutting out pasta, bread, rice or potatoes, and you can even have a pudding.
Dr Michael Mosley has developed a range of recipes – including this steak and carrot dish – which has less than 450 calories per serving and can aid weight loss
If you could do with losing a few pounds, then you aren’t alone. A third of British adults are overweight – and a further 25 per cent of the population is obese, which is a medical term for very overweight.
Public Health England says that the average adult consumes up to 300 more calories a day than is recommended – which is 2,500 a day for men, and 2,000 for women.
Type 2 diabetes and pre-diabetes are predominantly linked to weight gain.
But, as one of the UK’s foremost researchers into diet explains, it’s not what you eat, it’s just eating too much of anything that makes you gain weight.
Professor Michael Lean, chair of human nutrition at the University of Glasgow, says: ‘The scientific evidence is extensive, consistent and very clear. The cause of type 2 diabetes, in susceptible people, is weight gain and specifically waist-size increase – which indicates fat accumulation in the vital organs, and particularly fat in the liver.
‘The specific diet has little influence. It is weight gain that matters, and you don’t need to be very overweight or obese to be affected.’
The exact way diet reverses type 2 diabetes and pre-diabetes is just as simple, he adds. ‘It happens if there is weight loss of 10kg to 15kg – or 1st 8 lb to 2st 5 lb – whatever the starting point. This leads to loss of the excess fat in the liver.’
It’s the age old equation – consume fewer calories than you burn. ‘The diet composition does not matter as long as there is weight loss,’ Prof Lean says.
Busting the myths of going low-carb
The idea that very-low-carb diets are good for those with type 2 diabetes – or those at risk of the condition – comes from the theory that carbs raise the amount of insulin produced by the body.
Raising insulin increases the appetite, and reduces the body’s natural ability to burn off fat, or so it’s often claimed. If we believe the theory, it means that eating fewer carbs should cause us to lose weight. However, the problem is it has never been proven.
Professor Gary Frost, chair of nutrition and dietetics at Imperial College London says: ‘There is no good scientific evidence that shows increased carbohydrate intake leads to high levels of insulin that, in turn, drives up appetite.’
And according to Prof Lean, the idea that low-carb diets have a magical advantage over other weight-loss methods is a myth. Individual studies have suggested that going low-carb shifts weight fast, and significantly reduces blood sugar.
Current healthy eating guidelines suggest carbs should make up about a third of meal – about 260g of carbohydrate a day
But in the longer term, there is no advantage to the approach over many other diets, according to the best evidence. ‘There is no unique effect from low-carb diets on body fat, diabetes, blood pressure or cholesterol,’ Prof Lean adds.
Current healthy eating guidelines suggest carbs should make up about a third of meal – about 260g of carbohydrate a day.
The new Low Carb Program suggests initially limiting carbs to between 130g and 150g a day. This isn’t all that restrictive when you consider a bowl of porridge contains about 35g of carbs and a Tesco chicken sandwich has 42g. ‘Following a diet like this may well result in weight loss,’ says Prof Frost. ‘But that’s because by limiting carb intake, you’ll also limit calories.’
The Low Carb Program also offers advice on reducing carbs further, to 30g a day. However, Prof Frost points to studies that suggest very low-carb diets can increase cholesterol – and, therefore, the risk of heart disease – because people consume a greater proportion of their calories from fat. One large study in April found that people who ate the least amount of carbs were at greatest risk of dying from cancer, heart disease and stroke. And according to soon-to-be-published data from Prof Lean and his team, very low-carb diets may lead to nutritional deficiencies that increase the risk of type 2 diabetes.
Why keeping the weight off is key
The proof that weight loss can reverse type 2 diabetes comes from a long-running trial led by Prof Lean and his colleague, Professor Roy Taylor.
They found that a diet of just over 800 calories a day, followed for 12 to 20 weeks, can lead to rapid weight loss and put the disease into remission. But weight loss alone is not enough to get rid of type 2 diabetes. The crucial part, the researchers found, is keeping the weight off.
Once volunteers in the trial finished the initial, very-low-calorie phase of the diet, they no longer had to count calories. Instead, the simply followed the Government’s EatWell plate – which allows a third of the diet to be carbs – and consumed plenty of wholegrains, fruit and vegetables, lean meats and pulses.
After two years, a third of volunteers had stayed a healthy weight, and were still in diabetes remission. Studies have since found a similar approach works for pre-diabetes.
Finding a diet that you like make it easier to stick with than a regime that is a chore
In Prof Lean and Prof Taylor’s study, the participants were given low-cal shakes to make it easy for people to lose weight. Prof Taylor told The Mail on Sunday that the diet would have the same results if people could cut down on ordinary foods – carbs or otherwise.
‘Some people suit low-carb diets extremely well and find it a very good way to lose weight,’ Prof Taylor says. ‘But it’s not something that is going to suit everybody.’
Browsing online, it’s not hard to find Facebook groups and websites devoted to very-low-carb diets, and even, in the most extreme cases, those which claim eating only meat – the so-called carnivore diet – is a route to weight loss, health and wellbeing.
And there are scores of anecdotes posted by those who claim such diets worked for them.
But this method has, thus far, not stood up to scientific scrutiny.
Prof Taylor adds: ‘For people with pre-diabetes, losing weight is important. This can be done by a moderately low-carb dier or a relatively higher carb, low-fat diet. Either would result in long term prevention of type 2 and appear safe. So I wouldn’t jump on a soap box and say low carb is the only way to go.’
Find a diet you like – and stick to it
Prof Taylor advises that, in fact, it is better to make as few changes as possible when trying to lose weight. ‘If keeping some carbs in your diet means you’ll be making less drastic changes, then you might be more likely to continue with the plan in the longer term,’ he says. ‘So do whatever works for you, whether that’s carbs, low carbs, or low fat. Meal replacements are very useful for the initial weight loss.’
Compliance with low-carb diets is ‘pretty appalling’, and the drop-out rates tend to be ‘huge’, according to Prof Frost. Studies which have compared groups taking low-carb, low-fat and Mediterranean diets found that, initially, those following a low-carb approach were more likely to stick to it. But after two years, the low-carb group had the highest rate of dropouts because it restricted their diet more severely.
Another study found 42 per cent of those on a low-carb diet dropped out over two years compared with 32 per cent following a low-fat approach. ‘Many people find very low carb diets really difficult, so they’re not a long term answer,’ says Prof Taylor. He adds: ‘Generally, the message for maintaining weight is about controlling our portion sizes and cutting down on snacks which are high in calories and therefore unhealthy. Sticking to a diet with lots of fruit and veg, lean meats, and wholegrain carbs like oats and lentils, will keep you stable and healthy without having to count calories.’
So what about puddings and sweet treats – surely they’re off the menu for good once pre-diabetes or type 2 diabetes is diagnosed? Not so, according to Thomas Sanders, professor of nutrition and dietetics at King’s College London.
Contrary to popular belief, studies have shown that people with type 2 diabetes are actually able to tolerate sugar as part of their diet. ‘You just need to control calorie intake,’ Prof Sanders says.
‘It doesn’t hugely matter whether that’s through refined sugar or complex carbohydrates.
‘Of course, eating fudge bars and crisps isn’t going to be nutritionally good for you, and it won’t fill you up. But a bit of chocolate if you’re craving it is fine as long as it’s not every day. The rule of thumb is to stick to 100 calories for a snack.’
Carbs are not your enemy
Carbohydrate is an umbrella term for the sugars, starches and fibres found in fruits, grains, vegetables and dairy products.
The body needs them for digestive health, for energy, growth and a whole host of other functions.
Carbs are generally broken down in the digestive system into single sugar molecules – most commonly glucose and fructose.
Carbs are generally broken down in the digestive system into single sugar molecules – most commonly glucose and fructose
So, whether you eat white bread, brown rice or a banana, the digestible carbs in these foods end up in the blood as the same thing: sugars.
Some low-carb advocates have claimed that, because all carb-containing foods end up as sugar molecules, eating them has an ‘equivalent effect’ on the body as consuming pure sugar.
But just how true is this?
Professor Gary Frost says: ‘It’s not. The problem is you’re not comparing like with like because table sugar is chemically different from white bread or rice, and therefore its effect on the body is different.
‘The carbs in bread or rice are broken down into 100 per cent glucose. But table sugar is 50 per cent glucose and 50 per cent fructose – a type of fruit sugar.
‘There is some evidence that fructose may increase the amount of fat in the blood, and that fat is then stored in the liver. If you’ve got diabetes, the effects could be damaging.’
It’s worth also knowing that the speed at which carbs are digested varies, depending on what else is in the foods themselves, such as fibre – which is also a carb, just an indigestible one – fat and protein. Fats in a meal will slow the digestion of carbs.
More complex carbs such as pasta, wholegrain bread, lentils and porridge also make you feel fuller for longer. But there are other factors, too, such as how foods are cooked – baked potatoes digest faster than crisps, for example – and what else is eaten at the same time. Going very-low-carb often means cutting out bread, potatoes, rice and also pulses, fruit and many vegetables. Doing this risks removing important sources of fibre – essential for bowel and cardiovascular health – from the diet.
Further proof that diabetes patients needn’t cut out carbs came in a review which analysed 56 studies involving nearly 4,000 people. It concluded a Mediterranean diet involving a moderate amount of carbs, and high in dietary fibre, was ‘the most effective dietary approach’ in managing blood sugar.