What About Canned Fruit?

Food cans used to be soldered with lead compounds—so much so that people living off of canned food may have died from lead poisoning. Thankfully, this is no longer a problem in the United States. Lead contamination was one of the first priorities of the Food and Drug Administration back in 1906, before it was even called the FDA. Newspapers now have online archives going back a century so we can read about landmark historical events like “FDA Proposes Lead-Soldered Cans Be Banned” from way back yonder in…1993. So even though it was a priority in 1906, the ban didn’t actually go into effect until 1995. Evidently it was complicated because lead solder was “grandfathered” in as a “prior-sanctioned” substance.

Now that the lead is gone, though, are canned foods healthy? It depends primarily on what’s in the can. If it’s SPAM or another processed meat product, for instance, I’d probably pass.

What about canned fruit? We know fruits and vegetables in general may help protect us from dying of cardiovascular disease, and, when it comes to preventing strokes, fruit may be even more protective. But whether food processing affects this association was unknown, as I discuss in my video Is Canned Fruit as Healthy? One study found that unprocessed produce, mostly apples and oranges, appeared superior to processed produce. But that study focused mainly orange and apple juice. It’s no surprise whole fruit is better than fruit juice.

What about whole fruit when it is in a can? Dietary guidelines encourage eating all fruit whether it’s fresh, frozen, or canned, but few studies have examined the health benefits of canned fruit…until now. Canned fruit did not seem to enable people to live longer. In fact, moving from fresh or dried fruit to canned fruit might even shorten one’s life. Therefore, perhaps dietary guidelines should stress fresh, frozen, and dried fruit rather than canned.

Why the difference? While there’s no longer lead in cans these days, there is bisphenol A (BPA), the plastics chemical used in the lining of most cans. BPA can leach into the food and might counterbalance some of the fruits’ benefits. Recently, for example, blood levels of this chemical were associated with thickening of the artery linings going up to the brains of young adults. Canned fruit is often packed in syrup, as well, and all that added sugar and the canning process itself may diminish some nutrients, potentially wiping out 20 to 40 percent of the phenolic phytonutrients and about half of the vitamin C.

Maybe one of the reasons citrus appears particularly protective against stroke is its vitamin C content. It appears the more vitamin C in our diet and in our bloodstream, the lower the risk of stroke. And the way to get vitamin C into the bloodstream is to eat a lot of healthy foods, like citrus and tropical fruits, broccoli, and bell peppers. “Therefore, the observed effect of vitamin C on stroke reduction may simply be a proxy for specific foods (eg, fruits and vegetables) that causally lower stroke” risk. How could the researchers tell? Instead of food, they gave people vitamin C pills to see if they worked—and they didn’t.

This might be because citrus fruit have all sorts of other compounds associated with lower stroke risk, proving that the whole is greater than the sum of its parts. You can’t capture Mother Nature in a pill. It’s like the apocryphal beta-carotene story. Dozens of studies showed that people who ate more beta-carotene-rich foods, like greens and sweet potatoes, and therefore had more beta-carotene circulating in their system, had lower cancer risk. What about beta-carotene supplements instead of whole foods? Researchers tried giving beta-carotene pills to people. Not only did they not work, they may have even caused more cancer. I assumed the National Cancer Institute researcher who did this study would conclude the obvious: produce, not pills. But, no. Instead, the researcher questioned whether he should have tried lower dose pills, alpha-carotene pills, pills with other phytochemicals, or maybe multiple combinations. After all, he said, “[i]t is likely that neither the public nor the scientific community will be satisfied with recommendations concerned solely with foods…”


Check out my other videos on the can-lining chemical BPA, including:

Is fresh fruit really that healthy? See:

Is it possible to get too much of a good thing? See How Much Fruit Is Too Much?.

Now that there’s no more lead in the cans, are there any other ways we’re exposed to the toxic heavy metal? I did a whole series on lead, which you can watch. See also:

I close with yet another screed against reductionism. For more on that, see my videos Why Is Nutrition So Commercialized? and Reductionism and the Deficiency Mentality.

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:

Why Doctors are So Drug Happy

Who funds most of the studies that show drugs are safe and effective? The drug companies themselves. This is the topic of my video Eliminating Conflicts of Interest in Medical Research.

“It is self-evidently absurd to look to investor-owned companies for unbiased evaluations of their own products…One result of the bias in this literature is that physicians learn to practice a very drug-intensive style of medicine. Even when lifestyle changes would be more effective, physicians and their patients often believe that for every ailment there is a drug.” It’s gotten so bad that “[p]hysicians can no longer rely on the medical literature for valid and reliable information.” That’s quite an accusation. Says who? Says a long-time editor of the New England Journal of Medicine, one of the most prestigious medical journals in the world.

To help expose some of the conflicts of interest corrupting the medical profession, the Drug Company Gift Disclosure Act was introduced in Congress where it died year after year until it was successfully integrated into the Affordable Care Act. Now, there’s a database detailing which doctors get the billions of dollars that are dished out, “permit[ting] patients to make better informed decisions when choosing health care professionals and making treatment decisions.” (I explain how you can easily look up your own doctor in my video Find Out If Your Doctor Takes Drug Company Money.)

In 2008, medical groups endorsed a version of the Act that didn’t require public disclosure unless doctors got at least $500 in gifts, but the 2009 version got stricter, requiring disclosure if you pocketed even $100, leading groups like the American Academy of Family Physicians to start to get a bit nervous. The final wording in Obamacare, however, requires disclosure of even a $10 meal, leading countries around the world to look to the United States for leadership in healthcare ethics. You don’t see that every day!

Now that we have this massive public record, we can really see how honest doctors have been. The financial disclosures by the authors of all the American College of Cardiology and American Heart Association guidelines were matched to the public disclosures of the hundreds of thousands of dollars they received from Big Pharma. The result? “The overall agreement between author and company disclosure was poor.” Nationally, female physicians each received thousands of dollars less than male doctors on average from drug companies each year, though it’s not clear if this is because the women were more ethical or the industry was sexist.

What about conflicts of interest for online clinical support websites? “Point-of-care evidence-based medicine websites allow physicians to answer clinical queries using recent evidence at the bedside” of a patient. Clinicians caring for patients are increasingly reviewing treatment recommendations on these sites to make clinical decisions in real time. For instance, if you’re with a patient, you can just whip out your phone and check one. It’s important that “[m]embers of groups developing formal clinical guidelines are discouraged from interacting with the health industry in a manner that may create a conflict of interest.” Researchers examined one such website called UpToDate, which seemed to provide the most comprehensive diagnoses. Did they find any conflicts of interest? Yes, in every single UpToDate article they examined.

So what do we do with this information? Let’s say we see an article claiming that candy consumption is not associated with health risks and the authors disclose that their research was supported by the National Confectioners Association, a group that used to run ads that said things like: “Put candy in their school lunch. It’s good for them.” We may want to take the results of that article with a grain of salt.

“The problem with financial COIs [conflicts of interest] is that you simply don’t know what to believe.” Maybe this “preoccupation with disclosure hijacked the debate…” Maybe, as Dr. Kassirer, the former chief editor of the New England Journal of Medicine, critiqued, the focus instead should be on eliminating commercial conflicts, not just disclosing them. It’s like campaign finance reform, where the issue is managed more by public disclosure rather than getting money out of politics. Indeed, he writes that “the vast attention paid to failure to disclose conflicts of interest is misplaced, and that more attention must be focused on the financial conflicts themselves.”

After Dr. Kassirer effectively resigned from the New England Journal of Medicine, disillusioned with the direction they were taking, Dr. Marcia Angell took over. She was the first female chief editor in the journal’s hundred-year history and lasted about a year. Medical journals “consistently refer to ‘potential’ conflicts of interest,” she wrote, “as though that were different from the real thing, and about disclosing and ‘managing’ them, not about prohibiting them. In short, there seems to be a desire to eliminate the smell of corruption, while keeping the money. Breaking the dependence of the medical profession on the pharmaceutical industry will take more than appointing committees and other gestures. It will take a sharp break from an extremely lucrative pattern of behavior.”


Why do funding sources matter? See my video Disclosing Conflicts of Interest in Medical Research.

The shameful practices of supposed science-based medicine websites, like UpToDate, are the very reason I started NutritionFacts.org in order to share the best available evidence without corrupting commercial influence. If you value my work, please consider becoming a supporter by making a recurring monthly donation to the 501c3 nonprofit that keeps NutritionFacts.org growing and thriving.

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:

Dishonest Doctors

One of the critical questions to ask whenever reading a medical journal article is, “Who funded the study?” In most journals, researchers are required to identify their sources of funding, so what’s the problem? Well, researchers can obscure the true origin of financial support: They can hide it, disguise it, or even launder the money through a front group. A case in point is a study downplaying the risks of lung cancer that was funded in part by the Foundation for Lung Cancer: Early Detection, Prevention, and Treatment. That doesn’t sound so bad until you realize it was underwritten by millions of dollars from a tobacco company. There’s no obligation to “disclose a funding source’s source of funding,” which allows “companies to evade financial disclosure requirements” and makes it harder to “follow the money trail.”

As I discuss in my video Disclosing Conflicts of Interest in Medical Research, why does the funding source matter? Every single one of eight reviews covering over a thousand studies found that research funded by industry is more likely to make conclusions that are favorable to industry. For example, why do some review articles on the health effects of secondhand smoke reach different conclusions than others? The only factor found was whether an author was affiliated with the tobacco industry. “This is a disturbing finding. It suggests that, far from conflict of interest being unimportant in the objective and pure world of science…it is the main factor determining the result of studies.”

Not that we’d even know, because 77 percent of authors failed to disclose the sources of funding. And that’s another problem: The responsibility to disclose funding sources is left entirely up to the authors. So, how many researchers divulge the truth? Evidently, a law was passed in Denmark requiring physicians to register any time they worked with industry, which allowed researchers to cross-reference the studies physicians published to see how honest they were. Forty-eight percent of the time, the conflicts of interest were not disclosed, “reinforc[ing] the perception that physicians simply don’t take conflict of interest seriously” (or at least Danish physicians don’t).

What about the United States? Historically, there had been “no means of confirmation or verification” when an American doctor said they had no conflict of interest. Then in 2007, hip and knee replacement companies were forced to pay hundreds of millions of dollars in fines for giving orthopedic surgeons illegal kickbacks. “[M]any orthopedic surgeons in [the] country made decisions predicated on how much money they could make—choosing which device to implant by going to the highest bidder….[W]e expect doctors to make decisions based on what is in the best interests of their patients,” said the Department of Justice’s U.S. Attorney of the District of New Jersey, “not the best interests of their bank accounts.” Part of the settlement was that the companies would have to make public all the payments they made to physicians. The release of those records offered a rare opportunity to see if physicians were telling the truth on disclosure forms. And, lo and behold, more than half of payments were not disclosed, totalling millions of dollars.

That was for surgeons and medical device companies. What about doctors and drug companies? The same thing happened: Drug companies were forced to disclose who they were paying off. In looking at the publications of the doctors who got the most money—at least $100,000—the study found that they were worse than the surgeons. In 69 percent of the cases, they failed to disclose their industry ties. The problem is that we just assume researchers are going to be honest and tell the truth, but these “findings suggest that the accuracy and completeness of [conflict-of-interest] disclosures cannot be assumed.” So, even when a paper says no conflict of interest, who knows if it’s really true.

A long-time editor-in-chief of the New England Journal of Medicine wrote a scathing piece on drug companies and doctors who failed to disclose hundreds of thousands of dollars from drug companies like GlaxoSmithKline, which has been fined literally billions of dollars for activities such as bribing and suppressing data. When GSK got results that were “commercially unacceptable,” the company just buried them. Billions of dollars in fines get assessed, but for drug companies, that may just be the cost of doing business. “As reprehensible as many [drug] industry practices are…much of the medical profession is even more culpable.” We can expect drug companies to prioritize the bottom line, but maybe we should expect more from the healing profession.


What else might your doctor not be telling you? See:

Good examples of conflicts of interest include:

Instead of just disclosing conflicts of interest, how about getting rid of them? That’s the subject of my video Eliminating Conflicts of Interest in Medical Research.

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: