How Could There Be Such a Disconnect Between the Science and Medical Practice?

“Most deaths in the United States are preventable and related to nutrition.” According to the most rigorous analysis of risk factors ever published, the Global Burden of Disease study, funded by the Bill and Melinda Gates Foundation, our diet is both the number-one cause of death and the number-one cause of disability in the United States, having bumped smoking tobacco down to number two. Smoking now kills about a half million Americans every year, whereas our diet kills thousands more.

If most death and disability is preventable and related to nutrition, then, certainly, nutrition is the number-one subject taught in medical school and the number-one topic your doctor talks with you about, right? How can there be such a disconnect between the science and the practice of medicine?

Let’s do a thought experiment. Imagine you’re a smoker in the 1950s. The average per-capita cigarette consumption was about 4,000 cigarettes a year. Think about that. In the 1950s, the average American smoked half a pack a day.

My video How Smoking in 1959 Is Like Eating in 2019 shows a series of 1950s tobacco ads featuring media stars, famous athletes, and even Santa Claus telling you to smoke. The message was clear: If you wanted to keep fit and stay slender, you made sure to smoke. Magazine ads also encouraged you to eat hot dogs to keep yourself trim, as well as lots of sugar to stay both slim and trim. One ad even claimed that sugar was less fattening than apples. Apples! Though one internal tobacco industry memo stated, “Apples connote goodness and freshness and we see many possibilities for our youth-oriented cigarette with this flavor.” They wanted to make apple-flavored cigarettes for kids. Shameless!

As those 1950s ads tell us, in addition to staying “fit,” staying “slender,” and “guard[ing] against throat-scratch”, “for digestion’s sake,” you could smoke. “No curative power is claimed for Philip Morris,” read one ad, “but—an ounce of prevention is worth a pound of cure.” Heeding that advice, it’s better to be safe than sorry, so you’d better smoke.

Like eating, smoking was a family affair. Marlboro ads featured babies with comment bubbles saying, “Gee, Mommy, you sure enjoy your Marlboro,” “You’re darn tootin my dad smokes Marlboro…he knows a good thing,” and “Just one question, Mom…can you afford not to smoke Marlboro?” In another ad from the 1950s featuring a stereotypically  nuclear family, the dad is given cartons of cigarettes from his doting children—one boy and one girl, of course—and even the dog has a carton as his doting wife looks on.

“Blow in her face and she’ll follow you anywhere” was one tobacco company’s tagline, and “No woman ever says no to Winchester” was another. After all, cigarettes are “so round, so firm, so fully packed.” After all, John Wayne smoked them…until he got lung cancer and died.

Back then, even the Flintstones were smoking, and so were the doctors. This is not to say there wasn’t controversy within the medical profession. Yes, some ads showed doctors smoking Camels, but, in others, physicians preferred Lucky Strikes, so there was some disagreement. Indeed, “eminent doctors…on high and impartial medical authority…call for Philip Morris.” Even “leading nose and throat specialists” couldn’t agree which cigarette is better for your throat. Probably best to stick to the science, and, touts another ad, “more scientists…smoke Kent…” This should not be rocket science—but even the rocket scientists had their favorite Viceroys for the “man who thinks for himself.”

Can you guess why the American Medical Association (AMA) “went on record as withholding endorsement of the Surgeon General’s Report on Smoking and Health, which documented the important role of cigarettes in…lung cancer”? A “gift from the tobacco companies” of ten million dollars may have had a little something to do with that. But why weren’t more individual doctors speaking out? There were a few gallant souls ahead of their time writing in to medical journals, as there are today, standing up against industries killing millions, but why not more? Maybe it’s because “the majority of physicians themselves smoke[d] cigarettes,” just like the majority of physicians today continue to eat foods that contribute to our epidemics of dietary diseases. What was the AMA’s rallying cry back then? Everything “in moderation.” The AMA said “[e]xtensive scientific studies have proved that smoking in moderation” is okay.

Eating the Standard American Diet today is like being a smoker in the 1950s. Just as smoking was rampant back then, think about what we’re feeding even hospital patients to this day.

We don’t have to wait until society catches up with the science. Sometimes it takes a whole generation for things to change in medicine. The old guard of smoking physicians and medical school professors die off, and a new generation takes its place—but how many people need to die in the interim?


I try to answer the question that arises in the minds of pretty much anyone dipping even  a single toe into the lifestyle medicine literature: “Wait a second. If this were true, why didn’t my doctor tell me?” If, for example, our number-one killer can be reversed through diet, why isn’t it front-page news and taught to every medical student, broadcast from every mountaintop by medical organizations, and featured in our government dietary guidelines? Still confused? Check out my other videos that address these questions:

For more on the parallels between smoking then and eating today, see:

Is the risk of smoking really comparable to following the Standard American Diet, though? See Animal Protein Compared to Cigarette Smoking and Will Cannabis Turn Into Big Tobacco?.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

The Disconnect Between Science and Policy

Back in 1912, when hardly anyone smoked cigarettes, lung cancer was like a museum curiosity: extremely rare. In the next few decades, however, it rose dramatically around the world, roughly fifteen-fold. But researchers had already nailed it way back then. By mid-century, the evidence linking lung cancer and tobacco was considered overwhelming. Says who? Says the tobacco industry’s own research scientists in an internal memo. We now know that “senior scientists and executives within the cigarette industry knew about the cancer risks of smoking at least as early as the 1940s.”

Publically, though, they said things like, “Sure there are statistics associating lung cancer and cigarettes. There are statistics associating lung cancer with divorce, and even with lack of sleep. But no scientist has produced clinical or biological proof that cigarettes cause the diseases they are accused of causing.”

What was the government saying? My video American Medical Association Complicity with Big Tobacco includes several real cigarette advertisements, including one in which a leading U.S. Senator advises readers to smoke Lucky Strikes. Who wouldn’t want to “give [their] throat a vacation,” as another ad proclaimed? Others assured “not one single case of throat irritation,” and how could your throat and nose be adversely affected when cigarettes “are just as pure as the water you drink”? What if you do feel irritation from smoking? No problem—your doctor can write you a prescription for cigarettes, according to an ad from the Journal of the American Medical Association. After all, “don’t smoke” is advice hard for patients to swallow, as we’re told in another ad.

This reminds me of the recent survey of doctors that found the number-one reason doctors don’t prescribe heart-healthy diets was their perception that patients fear being deprived of all the junk they’re eating. After all, Philip Morris reminded doctors in an ad that we want to keep our patients happy and to “make a radical change in habit…may do harm.”

The tobacco industry gave medical journals big bucks to run ads like the ones I’m sharing with you. Should we be concerned about a conflict of interest? Not if we listen to Philip Morris, who assured us their “claims come from completely reliable sources” based on studies conducted by “recognized authorities…whose findings have been published in leading medical journals.” They even kindly offered to send free packs of cigarettes to doctors so they can test them out themselves and invited physicians to “make the doctors’ [smoking] lounge your club” at the American Medical Association convention.

What did the AMA have to say for itself? Like most other medical journals, they accepted tobacco ads but asserted that “[p]ostmortem examinations do not reveal lesions in any number of cases that could be definitely traced to the smoking of cigarettes.” So, as far as the AMA was concerned, case closed.

In fact, even after the Surgeon General’s Report on Smoking and Health came out, the American Medical Association, American Cancer Society, and Congress continued to drag their feet. The government was still subsidizing tobacco, just as our tax dollars subsidize the sugar and meat industries today. The AMA actually went on record refusing to endorse the Surgeon General’s report. Could that have been because they had just been handed ten million dollars from the tobacco industry?

Today the money is coming from big food. The American Academy of Family Physicians has accepted large sums of money from Coca-Cola “to fund patient education on obesity prevention.” I wonder what that pamphlet will say.

Who was featured as a top partner on Coca Cola’s website? The American College of Cardiology.

Just as it would have been hazardous to your health to take the medical profession’s advice on your smoking habits in the 1950s, it may be hazardous to your health today to take the medical profession’s advice on your eating habits.


If the balance of scientific evidence favors plant-based eating, why isn’t the medical profession at the forefront of encouraging people to eat healthier? That’s the question this video tries to answer. Looking back to smoking in the 1950s, we can see how all of society, the government, and even the medical profession itself could be in favor of habits that decades of science had already overwhelmingly condemned as harmful.

For more on the influence industry can have on food policy, see:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Risks vs. Benefits of Colonoscopies

Though colonoscopies can cause serious harm in about 1 in every 350 cases, sigmoidoscopies, procedures that use shorter and smaller scopes, have ten times fewer complications. But, do colonoscopies work better? Is their total risk-benefit better? We don’t know since we don’t have results from any randomized, controlled colonoscopy trials, and we won’t until the mid-2020s. So, what should we do in the meanwhile?

As I discuss in my video Should We All Get Colonoscopies Starting at Age 50?, the U.S. Preventive Services Task Force (USPSTF), the official prevention guidelines body, considers colonoscopies just one of three acceptable colon cancer screening strategies. Starting at age 50, we should either get our stool tested for hidden blood every year, which doesn’t involve any scoping at all; get a sigmoidoscopy every five years, along with stool testing every three; or get a colonoscopy every ten years. In terms of virtual colonoscopies or the new DNA stool testing, there is insufficient evidence to recommend either of those two strategies.

Though the USPSTF recommends ending routine screening at age 75, that assumes you’ve been testing negative for 25 years since your 50th birthday. If you’re 75 and have never been screened, then it’s probably a good idea to get screened at least into your 80s.

If there are three acceptable screening strategies, how should one decide? The USPSTF recommends that patients work with their physician in selecting one after considering each option’s risks and benefits. For patients to participate in the decision-making process, though, they have to be given the information. The degree to which health providers communicate the necessary information was not known until researchers conducted a study in which they audiotaped clinic visits looking for the nine elements of informed decision-making: discussing both the patient’s role and that role in making the decision, what kind of decision has to be made, the alternatives, the pros and cons of each option, and the uncertainties associated with the decision, as well as assessing the patient’s understanding and whether they desire input from those they trust, and, finally, asking them what they would prefer. That’s the role of a good doctor. It’s your body; it’s your informed decision.

How many of these nine crucial elements of informed decision-making were communicated to patients when it came to colon cancer screening?

Care to hazard a guess?

In most of the patients, none. The average number addressed? One out of nine. As an editorial in the Journal of the American Medical Association put it, “There are too many probabilities and uncertainties for patients to consider and too little time for clinicians to discuss them with patients.” So, doctors just make up the patients’ minds for them. And what do they choose? Most often, as in this survey of a thousand physicians, doctors recommend colonoscopy. Why? Other developed countries mostly use the stool tests, with only a few recommending colonoscopies or sigmoidoscopies. That may be because most physicians in the world don’t get paid based on how many procedures they do. As one U.S. gastroenterologist put it, “Colonoscopy is the goose that laid the golden egg.”

A New York Times exposé concluded that the reason doctors rake in so much money is less about “top-notch patient care” and more about business plans maximizing revenue, lobbying, marketing, and turf battles. Who sets the prices for procedures? The American Medical Association, the chief lobbying group for physicians, does. No wonder gastroenterologists pull in nearly a half-million dollars a year, and the American Gastroenterological Association wants to keep it that way. Referring to these exposés, the president of the association warned that “gastroenterology is under attack and colorectal cancer screening and prevention may be reduced in volume and discounted.” But, they then go on to share tips for how to succeed in the coming nightmarish world of accountability and transparency.

Why would primary care doctors push colonoscopies? Because many doctors get what are essentially financial kickbacks for procedure referrals. Studying doctor behavior before and after they started profiting from their own referrals, it’s estimated that doctors make nearly a million more referrals every year than they would have if they there were not personally profiting.


Serious harm in 1 out of 350 colonoscopies? See What to Take Before a Colonoscopy for all the gory details.

Too often, truly informed consent is a joke in modern medicine. For more on this, see:

How do you know if your doctor is on the take? Check out Find Out If Your Doctor Takes Drug Company Money.

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations: