Hippocrates might have pronounced that food should be our medicine, but it's advice that doctors have been ignoring for the past 100 years. And they really should have been listening, as underscored by a new research study that has discovered one in five deaths around the world every year is the direct result of a poor diet.
Add to that the 40 percent of cancers and the many cases of diabetes and heart disease caused by bad eating habits, and it's clear that a healthy diet is the single most important factor for maintaining health and preventing disease.
But don't just blame the doctor. Medical schools aren't teaching nutrition, and health agencies that lay down the guidelines for best practice are not pushing nutritional approaches as a valid way to treat chronic disease—even though there is an abundance of evidence to demonstrate that nutrition plays a pivotal role in preventing and reversing many health problems.
The latest such study, which tracked diet and health in 195 countries for 27 years, concluded that 11 million deaths a year—roughly 5 percent of all deaths worldwide—are caused by poor diet, defined as low intake of whole grains, fruits, vegetables, nuts and seeds, and high levels of sodium and trans fats from processed "fast" foods, baked goods, sugary drinks and red and processed meats.1
"This study affirms that poor diet is responsible for more deaths than any other risk factor in the world," said lead researcher Dr Christopher Murray from the University of Washington.
Although health agencies have focused their public health alerts on fast and sugary foods as things to avoid, the researchers discovered that not eating enough fruits and vegetables had a far bigger impact on health and longevity.
Others agree. Taking a one-year snapshot of heart disease, diet and death in the US, researchers from the Tufts Friedman School of Nutrition Science and Policy in Boston recorded 702,308 deaths in 2012 from cardiometabolic diseases, which includes heart disease, stroke and diabetes, and more than 45 percent of them were directly caused by diet.
Most of these deaths were attributed to not eating enough nuts, seeds and omega-3 fatty acids from seafood, and consumption of too much salt (sodium) and processed meats.2
Cancer, too, could be prevented by eating a healthy diet. Up to 40 percent of all cancers are caused by a poor lifestyle and diet, and reducing the amount of refined flour and concentrated sugars in our diet, while eating more fruits, cruciferous vegetables like broccoli and cauliflower, and chlorophyll from green vegetables such as spinach, could reduce the rate of breast, colorectal and prostate cancers by 70 percent, and that of lung cancer by as much as 50 percent.3
So why isn't your doctor telling you this? While some will give you the rudimentary advice to eat more fruits and vegetables and cut down on sweets and processed foods, none are taught the biological complexities of food and diet or the way nutrition can be harnessed to reverse disease.
It's even started to worry the American Heart Association (AHA), an advocate of the drugs-first approach to heart therapy. Spurred on by rising rates of diabetes, obesity, high blood pressure and other chronic diseases, the AHA commissioned an expert panel to discover why this increase is happening, especially as doctors have been giving patients basic dietary advice for years.
Essentially, it comes down to the simple fact that doctors aren't being taught anything beyond those basics, recommendations that could have been gleaned in a tabloid newspaper.
It's an educational gap that goes back decades, says panel chairperson Dr Karen Asprey. Even the barest minimum of 25 hours of instruction in nutrition and diet, which was recommended in 1985, is being met by fewer than 30 percent of medical schools in the US.4
The average teaching time is just 19 hours, suggesting there is little recognition that "obesity and cardiovascular disease are linked to poor nutrition and poor diet quality," Asprey added.
And nobody really cares if doctors understand what they're being taught. There's no testing, and diet doesn't appear on any examination papers, said Dr David Eisenberg at the Harvard T H Chan School of Public Health.
"It is a scandal that health professionals are not introduced to these facts above and beyond minimal information about nutritional deficiencies in biochemistry, and that these things do not appear on their examinations to become a practicing physician.
"Nor are they required on board certification, whether it's to become an internist, cardiologist, endocrinologist—you name it."5
We know nothing
Doctors don't disagree. A BBC survey of UK doctors discovered they knew next to nothing about the impact that diet and lifestyle have on health, and what they are taught about nutrition isn't relevant or applicable to the problems they see in practice.
Around 80 percent of the patients he treats have problems caused by poor lifestyle and diet, Dr Rangan Chatterjee told the BBC. In 2016, he was one of the signatories to a letter to the UK's General Medical Council and Medical Schools Council that called for the introduction of teaching of "evidence-based lifestyle interventions."6
It's the same the world over. In one survey, 87 percent of Canadian medical students said their undergraduate programs should dedicate more time to nutrition, and most doctors graduating from American medical schools said they lacked the confidence and training to advise patients on nutrition.7
Sorry, not here
So, if nutrition is pivotal in disease prevention and cure, why isn't it being taught? The problem goes deeper than just the medical schools— it seems to be systemic throughout medicine.
NICE (National Institute for Health and Care Excellence), the UK agency that determines the most effective treatments, dismisses out of hand any nutritional therapies.Rufus Greenbaum, who is a "registered stakeholder" with NICE, says his submissions on 20 diseases—all of which have suggested therapeutic levels of vitamins—have been rejected.
Even though there is strong evidence that nutrition helps with early-stage breast cancer, macular degeneration, diabetes and thyroid diseases, among others, NICE has ruled that it would not be considering this information when recommending the best approaches to treat the diseases.
"It's not a conspiracy. I honestly believe they don't understand about the effectiveness of nutrients," said Mr Greenbaum, director of the nutritional company GreenVits.
To illustrate the point, he recalls talking about using nutrients to treat macular degeneration with three leading ophthalmologists. Two of them said they knew nothing about nutrition, and the third, the most senior of the three, asserted that "vitamins are dangerous."
Going deeper still, the seeds of this nutritional blindness can be found in the groundbreaking Flexner Report of 1910, which laid the foundations for the teaching of modern "scientific medicine" in American medical schools, a blueprint that would spread around the world.
Schools that were teaching homeopathy, natural medicine and nutrition were closed and replaced by those that embraced the new medicine of pharmaceuticals and the treatment of symptoms. One benefactor was oil magnate John D Rockefeller, who funded new colleges that extolled the virtues of the first generations of pharmaceuticals, made from the petrochemical offshoots of his core product.
This limited view of disease and healthcare seems inadequate today. One doctor, fresh out of medical school, related the day she was approached by an obese woman who wanted to know how she got into that state.
"The patient was asking a straightforward question, and I think she was expecting a straightforward answer," she said—but her training hadn't given her the knowledge to respond. She just didn't know.
Wouldn't it be NICE?
NICE (the National Institute for Health and Care Excellence) sets the UK guidelines for the best, most effective practices for doctors to follow.
But the group won't even consider a nutritional approach, despite the overwhelming evidence, as one of its submission team, Rufus Greenbaum, has revealed. Here are some of his suggestions about cancer treatment and care, and NICE's responses.