Despite the most widely accepted and well-established chronic disease practice guidelines uniformly calling for lifestyle change as the first line of therapy, doctors often don’t follow these recommendations. As seen in my video, The Best Kept Secret in Medicine, lifestyle interventions are not only safer and cheaper but often more effective in reducing heart disease and failure, hypertension, stroke, cancer, diabetes, and deaths from all causes than nearly any other medical intervention.

“Some useful lessons may come from the war on tobacco,” Dr. Neal Barnard wrote in the American Medical Association’s ethics journal. When he stopped smoking himself in the 1980s, the lung cancer death rate was peaking in the United States. As the prevalence of smoking dropped, so have lung cancer rates. No longer were doctors telling patients to “[g]ive your throat a vacation” by smoking a fresh cigarette. Doctors realized they were “more effective at counseling patients to quit smoking if they no longer had tobacco stains on their own fingers.” “In other words, doctors went from being bystanders—or even enablers—to leading the fight against smoking.” And today, says Dr. Barnard, “Plant-based diets are the nutritional equivalent of quitting smoking.”

“If we were to gather the world’s top nutrition scientists and experts (free from food industry influence),” read one journal editorial, “there would be very little debate about the essential properties of good nutrition. Unfortunately, most doctors are nutritionally illiterate. And worse, they don’t know how to use the most powerful medicine available to them: food.”

Physician advice matters. When doctors told patients to improve their diets by cutting down on meat, dairy, and fried foods, patients were more likely to make dietary changes. It may work even better if doctors practice what they preach. Researchers at Emory University randomized patients to watch one of two videos. In one video, a physician briefly mentioned her personal dietary and exercise practices and visible on her desk were both a bike helmet and an apple. In the other video, she did not discuss her personal healthy practices, and the helmet and apple were missing. In both videos, the doctor advised the patients to cut down on meat, not usually have meat for breakfast, and have no meats for lunch or dinner at least half the time. In the disclosure video, the physician related that she herself had successfully cut down on meat. Perhaps not surprisingly, patients rated that physician to be more believable and motivating. Physicians who walk the walk—literally—and have healthier eating habits not only tend to counsel more about exercise and diet, but have been found to seem more credible or motivating when they do so.

It may also make them better doctors. A randomized controlled intervention to clean up doctors’ diets, called the Promoting Health by Self Experience (PHASE) trial, found that healthcare providers’ personal lifestyles were correlated directly with their clinical performance. Healthcare providers’ improved wellbeing and lifestyle cascaded to the patients and clinics, suggesting an additional strategy to achieve successful health promotion.

Are you ready for the best kept secret in medicine? Given the right conditions, the body can heal itself. For example, treating cardiovascular disease with appropriate dietary changes is good medicine, reducing mortality without any adverse effects. We should keep doing research, certainly, but educating physicians and patients alike about the existing knowledge regarding the power of nutrition as medicine may be the best investment we can make.

Of course, to advise patients about nutrition, physicians first have to educate themselves, as it is unlikely they received formal nutrition education during their medical training:

For more on the power of healthy living, see:

In health,

Michael Greger, M.D.