How to prevent diabetes

“Your blood sugar is too high. You have pre-diabetes.” 

When Gail Tudor heard her doctor say that in July 2014, the 54-year-old wedding videographer was shocked. How could she? She had a body mass index of 24 and she followed the NHS recommended diet low in fat and high in fruits, vegetables and healthy grains. Plus Gail, a mother of two who lives in Wales, was very active—skating, walking, kayaking and more. 

Since she already did those things, her doctor said, it was unlikely Gail could reverse her path to type 2 (T2) diabetes. She was offered a treatment plan including drugs, and was told that it was likely she’d need them for the rest of her life. 

“I couldn’t believe it,” Gail says. She determined to learn what else she could do to prevent diabetes from developing—without drugs.

Retired Engineer, Frank Linnhoff, 69, who lives near Bordeaux, France, knew his obesity and his family history put him at high risk of T2 diabetes. His father had died aged 70 from kidney failure caused by the disease and his brother had a leg amputated at 45 because of it. Diagnosed with pre-diabetes years earlier, Linhoff had tried to follow his doctor’s advice on diet and exercise, but still his weight climbed. 

In January 2015, he was feeling so poorly he went for a blood test. The results showed his fasting blood glucose was sky-high. He knew if he went to the doctor he’d be diagnosed with diabetes. “I was so shocked that I was up all night, searching the internet for answers,” he says. “My father and brother had failed to control their diabetes; I couldn’t have the same fate.” He was determined to pull himself back from the precipice. 

If you think your have diabetes, you may need a blood test to check your blood sugar levels

In August 2015, at age 57, I too was told by my doctor that my fasting blood sugar was in the pre-diabetes range. Like Gail I wasn’t overweight. My BMI was a healthy 23.7. I exercised three times a week and walked 10,000 steps every day. Moreover, as a health writer for more than 25 years, I’d been following all the recommended dietary guidelines for decades. What more could I do?

I began searching the medical literature for the most up-to-date facts and views. 

Pre-diabetes, I learned, is a warning flag of health troubles down the road for tens of thousands of men and women in Europe this year who’ll be told that they have it. An estimated one in three UK adults already do, and the International Diabetes Foundation estimates that in Europe, around five per cent of adults aged 20–79 are already living with impaired glucose tolerance and are at increased risk of developing diabetes. Pre-diabetes increases the risk up to ten times for developing eventual T2 diabetes with its dire rates of heart disease, stroke, blindness, nerve damage and limb amputations. What’s more, damage to the body’s tissues and blood vessels can start well before full-blown T2 diabetes occurs.  

Often causing or accompanied by hyperglycemia, pre-diabetes is linked to a problem with the body’s insulin, a hormone that moves sugar out of the blood and into cells for energy use or storage as fat. When pre-diabetes occurs, higher and higher amounts are being churned out that no longer work as effectively—a process called insulin resistance. As a result, too much sugar is left circulating in the blood, which leads to higher blood-sugar levels as well as the higher risk of type 2 diabetes.

Soaring rates of T2 diabetes are a massive health problem, not only for the individuals facing its many consequences, but for the health systems burdened by the growing numbers of patients. 

Worldwide, rates of the disease have almost quadrupled since 1980. In the last decade alone, T2 diabetes rates in the UK have increased 65 per cent and according to Diabetes UK’s 2016 report, if the current trends persist, by 2034 a staggering third of Britons will be obese, while T2 diabetes will develop in ten per cent of the population. 

The good news is pre-diabetes is reversible with lifestyle changes. The choice is yours. In fact, Gail Tudor, Frank Linnhoff and I have all eliminated our pre-diabetes since our diagnoses and greatly improved our health. So have thousands of others.

If you or a loved one has been told you have pre-diabetes, here’s what you need to know. 

Being overweight or obese, inactive or from a family with a history of T2 diabetes makes you more likely to get a pre-diabetes diagnosis. Women like Gail who have had gestational diabetes (a type that affects women during pregnancy) are at much higher risk of developing pre-diabetes or T2 diabetes. So are women who have given birth to a baby weighing over nine pounds—as I did some 23 years ago.

I also had a related condition that up to 20 per cent of European women may have: a genetic, hormonal condition called Polycystic Ovary Syndrome (PCOS), which causes lowered fertility, potential weight gain and other symptoms. A key feature of PCOS, just like diabetes, is insulin resistance.

Symtpoms of diabetes include weight gain and increased thirst

“Insulin’s action is the key,” notes Dr Jason Fung, a Canadian nephrologist, the majority of whose kidney failure patients have T2 diabetes. Dr Fung has recently written the international bestseller The Obesity Code, in which he describes how insulin, insulin resistance and the stress hormone cortisol are the key hormonal triggers to T2 diabetes and obesity. 

Since pre-diabetes generally has no symptoms, it’s detected through a blood-screening test, generally in one of three ways:

It’s been known for years that losing five to ten per cent of your body weight can reverse pre-diabetes for a time. But as we all know, most diets are hard to maintain and weight is eventually regained (sometimes more than was lost). With this usually comes the return of poor blood-sugar results.

But here’s the new, somewhat controversial approach: thousands of people like Gail Tudor, Frank Linnhoff and me have lost weight and reversed diabetes risk factors by cutting sugar and refined or starchy carbohydrates (bread, potatoes, rice, pasta, cereals, biscuits and cakes) out of our diets and upping the proportion of healthy fat.

All carbohydrates get turned into sugars by digestion in our body. That sugar then triggers the release of insulin. So reducing or eliminating most carbs to under 100g a day lowers the amount of sugar in the blood—and thereby the need for insulin to respond to it, notes Dr Fung. Doing so helps re-sensitise us to insulin. “Diabetes and pre-diabetes should really be called carbohydrate intolerance,” says Dr Aseem Malhotra, a cardiologist, advisor to the National Obesity Forum and a founding member of the UK “Action on Sugar” campaign to remove or reduce added sugars in all of our diets.

Low-carb diets have been around for years, but adding healthy fat is the new twist. Fats from dairy, nuts, fish and eggs (including the yolk) are healthy, whereas overconsumption of vegetable oils and trans fats can lead to chronic disease. A growing body of evidence shows our 30-year message to avoid fat has been misguided. In fact, fat instead is satiating, good for the heart and brain, and—compared to other food groups—has the least impact on insulin release.

Swedish diabetes researcher Dr Fredrik Nystrom agrees. His advice? “Carbohydrate restriction in combination with the high-fat Mediterranean diet.”

A study published in June last year in The Lancet Diabetes & Endocrinology journal found that a high-fat Mediterranean diet did not lead to weight gain. In fact, men and women in the higher-fat group lost more weight and inches from their waist than the low-fat group.

A Mediterranean diet could be a useful tool for preventing diabetes

Gail Tudor started the low-carb/high-fat (LCHF) approach in July 2014; by May 2015 she’d lost more than 14lbs—mostly within the first three months, even though weight loss was not her intention. Her blood sugar had returned to healthy ranges, bringing her pre-diabetes under control. Frank Linnhoff, who started LCHF in January 2015, has lost more than 20lbs and his blood sugar is now normal—and so is his blood pressure. I started the diet in autumn 2015 and after seven months had lost ten pounds and had my blood glucose return to normal. Better yet, the food is delicious and satisfying.

Does it work for everyone? No long-term studies have yet been published and most countries’ diabetes associations are opting to take a wait-and-see approach.

But a groundswell of vocal medical experts and scientific researchers, as well as tens of thousands of individuals who have tried it, now endorse the LCHF approach as safe and effective. Some of the growing evidence includes:

In January 2015, 26 international medical experts advocated carbohydrate restriction as the first approach to managing pre-diabetes and T2 diabetes in an article published in the journal Nutrition.

In May last year, the diabetes forum diabetes.co.uk announced that as part of a study where 120,000 people had signed up for its ten-week LCHF programme, the majority reported improved blood glucose and weight loss on the diet.

For almost a decade, Swedish GP Dr Andreas Eenfeldt has been counselling his pre-diabetes, T2 diabetes and obese patients to switch to a low-carb, high-fat diet. “In weeks and months they got better, their diabetes reversed and they could get off drugs,” said Dr Eenfeldt, who in 2007 started a non-commercial Swedish website dietdoctor.com. In 2010 his book Low Carb High Fat Food Revolution became a Swedish bestseller and was translated into eight languages. In 2011 he started the English dietdoctor.com site. 

Gail, Frank and I were all helped in our transformations by the website. Frank, along with the LCHF diet, is now cycling, dancing, enjoying life and celebrating his return to good health. “I felt so bad in January 2015. I never thought that just a year later I’d feel so wonderful.”

Regular exercise, boosting sleep quality and reducing stress have all been shown to help improve blood-glucose control, experts say. 

As a health writer I immediately understood the dangers of a pre-diabetes diagnosis. Over the last year, since my wake-up call, I’ve focused on making all these lifestyle changes, restricting carbs and sugar in my diet, lifting weights, walking everywhere and getting a good night’s sleep. 

I’ve lost a total of 13lbs to date, and I’ve kept them off. I bought a blood-glucose monitor and check my blood sugar regularly. I’m now always in the healthy range. Believe it or not, I actually feel lucky that I got that pre-diabetes scare: it’s helped me improve my health and avoid T2 diabetes.

As Dr Andreas Eenfeldt says, “We really need to spread this knowledge so that more people can benefit from it—and act accordingly to improve their health.”

Read more: What are the warning signs of diabetes?

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