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:

What’s the Secret to Latino Longevity?

Latinos living in the United States tend to have “less education, a higher poverty rate, and worse access to health care” and “represent the ultimate paradigm of healthcare disparities,” with the highest rate of uninsured, lowest rates of health screening and counseling, and poorest levels of blood pressure and blood sugar control, as well as “other measures of deficient quality of care.” So they must have dismal public health statistics, right? According to the latest national data, the life expectancy of white men and women is 76 and 81 years, respectively, and that of black men and women is shorter by a handful of years. And Latinos? Amazingly, they beat out everyone.

Latinos live the longest.

This has been called the Hispanic Paradox (now also known as the Latino Paradox), which I explore in my video, The Hispanic Paradox: Why Do Latinos Live Longer?. Latinos have a 24 percent lower risk of premature death and “lower risks of nine of the leading 15 causes of death,” with notably less cancer and heart disease. This was first noticed 30 years ago but was understandably was met with great criticism. Maybe the data were unreliable? No, that didn’t seem to be it. Maybe only the healthiest people migrate? Turns out the opposite may be true. What about the “salmon bias” theory, which “proposes that Latinos return to their home country…to ‘die in their home’” so they aren’t counted in U.S. death statistics? That theory didn’t pan out either.

Systematic reviews “confirm the existence of a Hispanic Paradox.” Given the strong evidence, it may be time to accept it and move on to figuring out the cause. The very existence of the “Hispanic Paradox” could represent “a major opportunity to identify a protective factor for CVD [cardiovascular disease] applicable to the rest of the population.” After all, whatever is going on “is strong enough to overcome the disadvantageous effect” of poverty, language barriers, and low levels of education, health literacy, quality of healthcare, and insurance coverage. Before we get our hopes up too much, though, could it just be genetic? No. As foreign-born Latinos acculturate to the United States, as they embrace the American way of life, their mortality rates go up. So, what positive health behaviors may account for Latino longevity?

Perhaps they exercise more? No, Latinos appear to be even more sedentary. They do smoke less, however the paradox persists even after taking that into account. Could it be their diet? As they acculturate, they start eating more processed and animal-based foods, and consume fewer plant foods—and perhaps one plant food in particular: beans. Maybe a reason Latinos live longer is because they eat more beans. Although Latinos only represent about 10 percent of the population, they eat a third of the beans in the United States, individually eating four to five times more beans per capita, a few pounds a month as opposed to a few pounds per year. That may help explain the “Hispanic Paradox,” because legumes (beans, split peas, chickpeas, and lentils) cool down systemic inflammation.

In my video, you can see the mechanism researchers propose in terms of lung health. While cigarette smoking and air pollution cause lung inflammation, which increases the risk for emphysema and lung cancer, when we eat beans, the good bacteria in our gut take the fiber and resistant starch, and form small chain fatty acids that are absorbed back into our system and decrease systemic inflammation, which not only may inhibit lung cancer development, but also other cancers throughout the body. Latinos have the lowest rates of chronic obstructive pulmonary disease (COPD) and lung cancer, and also tend to have lower rates of bladder cancer, throat cancer, and colorectal cancer for both men and women.

This “systemic inflammation” concept is also supported by the fact that when Latinos do get cardiovascular disease or lung, colon, or breast cancer, they have improved survival rates. Decreasing whole body inflammation may be important for both prevention and survival.

Asian Americans also appear to have some protection, which may be because they eat more beans, too, particularly in the form of tofu and other soy foods, as soy intake is associated with both preventing lung cancer and surviving it.

Hispanics also eat more corn, tomatoes, and chili peppers. A quarter of the diet in Mexico is made up of corn tortillas, and Mexican-Americans, whether born in Mexico or the United States, continue to eat more than the general population. Looking at cancer rates around the world, not only was bean consumption associated with less colon, breast, and prostate cancer, but consumption of rice and corn appeared protectively correlated, too.

Since NAFTA, though, the North American Free Trade Agreement, the Mexican diet has changed to incorporate more soda and processed and animal foods, and their obesity rates are fast catching up to those in the United States.

In the United States, Latinos eat more fruits and vegetables than other groups, about six or seven servings a day, but still don’t even make the recommended minimum of nine daily servings, so their diet could stand some improvement. Yes, Hispanics may only have half the odds of dying from heart disease, but it’s “still the number one cause of death among Hispanics. Therefore, the current results should not be misinterpreted to mean that CVD is rare among Hispanics.” Ideally they’d be eating even more whole plant foods, but one thing everyone can learn from the Latino experience is that a shift toward a more plant-based diet in general can be a potent tool in the treatment and prevention of chronic disease.


Data like this support my Daily Dozen recommendation for eating legumes ideally at every meal, and we have free apps for both iPhone and Android that can help you meet these dietary goals.

For more on the wonders of beans, split peas, chickpeas, and lentils, see my videos and love your legumes!:

What’s the best way to eat them? See Canned Beans or Cooked Beans? and Cooked Beans or Sprouted Beans?.

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:

From Adequate Nutrition to Optimum Nutrition

Research in human nutrition over the past four decades has led to many discoveries as well as a comprehensive understanding of the exact mechanisms behind how food nutrients affect our bodies. As I discuss in my video Reductionism and the Deficiency Mentality, however, the “prevalence of epidemics of diet-related chronic diseases, especially obesity, type 2 diabetes, osteoporosis, cardiovascular diseases, and cancers, dramatically increases worldwide each year.” Why hasn’t all this intricate knowledge translated into improvements in public health? Perhaps it has to do with our entire philosophy of nutrition called reductionism, where everything is broken down into its constituent parts; food is reduced to a collection of single compounds with supposed single effects. “The reductionist approach has traditionally been and continues today as the dominant approach in nutrition research.” For example, did you know that mechanistically, there’s a chemical in ginger root that down-regulates phorbol myristate acetate-induced phosphorylation of ERK1/2 and JNK MAP kinases? That’s actually pretty cool, but not while millions of people continue to die of diet-related disease.

We already know that three quarters of chronic disease risk––diabetes, heart attacks, stroke, and cancer—can be eliminated if everyone followed four simple practices: not smoking, not being obese, getting a half hour of exercise a day, and eating a healthier diet, defined as more fruits, veggies, and whole grains, and less meat. Think what that could mean in terms of the human costs. We already know enough to save millions of lives. So, shouldn’t our efforts be spent implementing these changes before another dollar is spent on research such as figuring out whether there is some grape skin extract that can lower cholesterol in zebra fish or even trying to find out whether there are whole foods that can do the same? Why spend taxpayer dollars clogging the arteries of striped minnows by feeding them a high cholesterol diet to see whether hawthorn leaves and flowers have the potential to help? Even if they did and even if it worked in people, too, wouldn’t it be better to simply not clog our arteries in the first place? This dramatic drop in risk and increase in healthy life years through preventive nutrition need not involve superfoods or herbal extracts or fancy nutritional supplements—just healthier eating. When Hippocrates supposedly said, “Let food be your medicine and medicine be your food,” he “did not mean that foods are drugs, but rather, that the best way to remain in good health is to maintain a healthy diet.” (Note: Hippocrates probably never actually said that—but it’s a great sentiment anyways!)

The historical attitude of the field of nutrition, however, may be best summed up by the phrase, “Eat what you want after you eat what you should.” In other words, eat whatever you want as long as you get your vitamins and minerals. This mindset is epitomized by breakfast cereals, which often provide double-digit vitamins and minerals. But the road to health is not paved with Coke plus vitamins and minerals. This reductionistic attitude “is good for the food industry but not actually good for human health.” Why not? Well, if food is good only for a few nutrients, then you can get away with selling vitamin-fortified Twinkies.

We need to shift from the concept of merely getting adequate nutrition to getting optimal nutrition. That is, we shouldn’t just aim to avoid scurvy, but we should promote health and minimize our risk of developing degenerative diseases.

Bringing things down to their molecular components works for drug development, for example, discovering all the vitamins and curing deficiency diseases. In the field of nutrition, “[h]owever, the reductionist approach is beginning to reach its limits.” We discovered all the vitamins more than a half-century ago. When is the last time you heard of someone coming down with scurvy, pellagra, or kwashiorkor, the classic deficiency syndromes? What about the diseases of dietary excess: heart disease, diabetes, obesity, and hypertension? Ever heard of anyone with any of those? Of course we have. Yet we continue to have this deficiency mindset when it comes to nutrition.

When someone tries to reduce their consumption of meat, why is “where are you going to get your protein?” the first question they get asked, rather than “if you start eating like that, where are you going to get your heart disease?” The same deficiency mindset led to the emergence of a multibillion-dollar supplement industry. What about a daily multivitamin just “as ‘insurance’ against nutrient deficiency?” Better insurance would be just to eat healthy food.


Professor Emeritus T. Colin Campbell wrote a Whole book about this issue, and I’m looking forward to doing many more videos on the topic.

So, where do plant-eaters get protein? Check out Do Vegetarians Get Enough Protein? to learn more.

The concept of optimal, rather than merely adequate, nutrition is illustrated well in this video about fiber: Lose Two Pounds in One Sitting: Taking the Mioscenic Route.

Other videos on reductionism include

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: