Gary Taubes jokes that his wife blames him for no longer being able to eat pasta and French fries. No wonder: as one of the world’s foremost anti-carb crusaders, he has devoted much of his 40-plus year career as an investigative journalist to exposing certain deeply-held beliefs about diet and nutrition as myths. His biggest bugbear? The medical consensus that a low-fat, carb-rich diet is the best we can eat for overall good health.
The clues are in the names of his books – The Diet Delusion, The Case Against Sugar, The Case for Keto. He’s not afraid to take on science, medicine and public health institutions and has fought the idea that a low-fat diet is the best way to tackle obesity and heart disease for decades.
But his new title takes on a much bigger, though related, problem. In Rethinking Diabetes, Taubes disputes the accepted approach to treating arguably the world’s, certainly the Western world’s, biggest health crisis.
Diabetes is a chronic disease suffered by 400 million people worldwide. Diabetes UK says that one in 15 Brits are living with diabetes, a figure that includes one million adults with undiagnosed type 2.
It develops when our blood sugar is too high because we aren’t producing any (type 1) or enough (type 2) insulin. Humans do need sugar – glucose – but we also need the insulin produced by the pancreas to break it down, so our bodies can use it as energy.
According to Taubes, we’re treating diabetes all wrong. What’s more, the answer isn’t rocket science. It’s something doctors had worked out and were successfully treating a century ago, before the hormone insulin was discovered and quickly packaged up as a wonder drug.
Insulin took off almost immediately as the best and only treatment for the rapidly exploding number of cases. Just as semaglutide is touted as a miracle “cure” for obesity today, so insulin was sold as diabetes’ silver bullet since its discovery in 1921, says Taubes. But these two modern illnesses are connected, and adults with obesity are at a high risk of developing type 2 diabetes.
Taubes isn’t a medical professional, but he’s geared up to take on the whole establishment. “It’s an odd situation for journalists to be challenging medical wisdom, health associations and physicians,” he admits from his home in Oakland, California. “I don’t even have diabetes myself, so I’m not a patient speaking from experience. But the evidence is pretty clear.”
The evidence, as he shows throughout Rethinking Diabetes: What Science Reveals about Diet, Insulin, and Successful Treatments (Granta Books, £16.99), is that we are treating diabetes as a chronic illness to be managed with medication. Why instead aren’t we searching for solutions, and for ways to reduce new cases and cure sufferers?
Although insulin has contributed to easing the day-to-day experience of anyone with diabetes, Taubes says it hasn’t controlled the epidemic in any way, even when administered with the most accurate and up-to-date technology and devices.
Worse, still, those dependent on insulin – most diabetics inject insulin to manage blood sugar – have not returned to good health. “The argument I make in my book,” he explains, “is that many of the complications of diabetes, that we assume are the complications of the disease, are quite likely the complications of the disease on this carbohydrate-rich diet.”
Taubes takes readers back to a time when few people had heard of diabetes. “In the 19th century, physicians might go years without seeing a case,” he says. “The start of it becoming a common disease, in the second half of the 19th century, coincides with the explosion of sugar, with chocolate, ice cream, and soda.”
The first doctor in the US to specialise in diabetes treatment was Elliott Proctor Joslin, the founder of the Joslin Diabetes Centre. His mother and aunt were diagnosed. As he saw more cases than most, he began to develop treatments and theories.
“The accepted therapy for diabetes was what they called an animal diet, of fatty meat and green leafy veg, which was boiled three times to reduce the carbohydrate,” explains Taubes. “They knew if they fed people carbohydrates, they would manifest the symptoms of the disease. But if they didn’t eat carbs, you could keep the adults alive indefinitely, and the children would live longer, too.”
It sounds straightforward, but it wasn’t exactly fun for those undergoing treatment. Some of the patients were malnourished from “starvation therapies”. Along came insulin, in 1921, and those given it would improve within hours. Type 1 diabetes was no longer a death sentence.
But Taubes says that over-reliance on insulin has created all sorts of other desperate health problems. “You go from treating patients with a diet that restricted carbohydrate as they couldn’t metabolise it, to giving them carbohydrate to balance out the insulin.”
Doctors wanted their patients to feel as if they could eat in the same way as everybody else did, to let children eat with other children, and let parents off cooking special meals.
“It seemed like a great idea, Taubes says, but 20 years later you started seeing the long-term implications, which were awful. Kidney failure, nerve damage which led to amputations, blindness …patients diagnosed at 14 or 15 would be kept alive for 20 years but still die in their thirties from awful things. Their bodies would just break down. The case studies are heart-breaking.”
But instead of questioning insulin therapy, doctors doubled down, says Taubes. “By that time people weren’t associating the side effects with the diet, they were associating the complications of the disease – these awful deaths – with not using enough insulin.” The idea that anyone with diabetes could eat in any way they chose was embedded in the medical community, as was the belief that fatty foods were bad for us.
Home blood glucose tests – the sort that make diets like the current ZOE app possible and are used by diabetics to manage their condition – weren’t around until late in the 20th century.
In 1969, Dr Richard Bernstein, who had been diagnosed with type 1 diabetes at 12, got hold of one to trial his hunch that diet affected his blood sugar levels, and that he could manage his illness more effectively via what he ate than what he injected.
He developed a low-carb diet that was initially dismissed by both the American Diabetes Association and the NHS, though both now agree to some extent that a low-carb lifestyle is beneficial for diabetics, it just isn’t the principal treatment. Instead, some nutritional advice tends to be given alongside medication.
“If my hypothesis is correct,” says Taubes, “if you teach people to eat without the carbs, not only do they not need the pills or the injections, but they ideally don’t have the complications.”
The rub? He can’t properly prove this, as the trials have never been done. But small scale evidence holds up extremely well. In the UK, for example, Dr David Unwin who calls himself the “low carb GP”, has been curing patients of diabetes for over a decade by prescribing diets high in fat and scant in carbs.
As Unwin himself said when the NHS named him “innovator of the year” in 2017, his approach is 200 years old. By 2022, 94 patients (20 per cent) had followed Unwin’s dietary advice and reversed their type 2 diabetes.
Taubes says that the UK is doing better than the US in terms of managing diabetes, but that the problem with a drug-based approach is that it might offer longevity, but it won’t ever reduce the prevalence of diabetes.
What about those with type 1 diabetes, who cannot produce any insulin? Taubes presents case study after case study who have changed their diet and cut down on medication. Isn’t it hard to stick to an extremely restrictive menu? He says that the headline that someone with diabetes can eat as everyone else does, simply isn’t true. What’s more, it doesn’t make them feel better. “The question becomes whether a diabetic patient values the freedom of eating what others eat more than the freedom that comes with greater function, health, and wellbeing.”
