CAN AN APPLE A DAY KEEP CANCER AWAY?: Although a diet rich in fresh fruits and vegetables has been shown to lower chances of suffering from cardiovascular disease and other ailments, a growing body of research is showing that these foods might not have more than a slight impact on overall cancer risk.
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Despite decades of entreaties from the World Health Organization (WHO) and mothers alike to eat more fruits and vegetables, a new study has found that these dietary additions appear to do little to decrease the overall likelihood of getting cancer.
The recommendation that people eat at least five servings (about 400 grams) of fruits and veggies each day, espoused by the WHO since 1990, was based on studies that found a link between higher intakes of these foods and lower risks for cancer and other diseases.
Since the 1990s, however, evidence from large studies has been mounting that the protective effects of these foods against cancer in particular might be modest—if it exists at all. (Other research has continued to show that diets high in fruits and vegetables are important for preventing conditions such as obesity and cardiovascular disease.) A new report, analyzing cancer incidence in 478,478 men and women ages 25 to 70 over more than eight years in 10 European countries, found "a very small inverse association between the intake of total fruits and vegetables and cancer risk," the researchers concluded.
Among those who have had the highest relative benefit from high fruit and veggie intake were smokers and heavy drinkers. They actually had a lower risk of getting the types of cancers they are prone to, such as respiratory and digestive ones, although their risk was still greater than their non-smoking and non-heavy-drinking counterparts. And although the men in the study seemed to have the lowest risk if they ate both fruits and vegetables, women appeared to also decrease their risk even if they only ate large amounts of vegetables. The researchers caution, however, that because the decreases in cancer rates, while statistically significant, were so small, the results should be used carefully.
About 6 percent of the people in the study were diagnosed with cancer during the follow-up period. The researchers concluded that if the results of the analysis can be broadly applied, upping daily fruit and vegetable consumption by about 150 grams (equivalent to about one cup of cherry tomatoes or 1.5 medium bananas), from most dietary levels, could prevent about 2.5 percent of all cancers in most populations. The results appeared online April 6 in the Journal of the National Cancer Institute.
The results are in line with other findings both in the U.S. and abroad that suggest the protective effect of fruits and vegetables is "much smaller than had been believed 10 years ago," Harvard School of Public Health's Walter Willett, who wrote an editorial accompanying the study, noted in an e-mail to ScientificAmerican.com. People who eat more fresh fruits and vegetables are also more likely to make other healthful lifestyle choices, such as exercising more and drinking and smoking less, which the researchers noted "may have contributed to a lower cancer risk" overall.
Counting cancers
To obtain their large sample, the researchers analyzed data collected for the European Prospective Investigation into Cancer and Nutrition (EPIC) project. Although the study was conducted throughout Europe, where residents of countries such as Greece and Italy are thought to have healthier diets to begin with, the researchers say that results would probably be similar if the analysis had been done in the U.S. "There is no reason to expect a different effect in the U.S. vs. Europe for a comparable level of consumption," Paolo Boffetta, of the Mount Sinai School of Medicine in New York and lead researcher on the study, wrote in an e-mail to ScientificAmerican.com. Those in the study reported that they ate a median of 335 grams of fruits and vegetables each day. Bnd if people in the U.S. ate fewer fruits and vegetables overall, he notes, "the magnitude of the effect would be seemingly lower."
Large cancer risk studies have increasingly been designed as so-called prospective studies, like this one. In a prospective study, participants are followed over time (e.g. across five years), and baseline information is compared with later follow-ups. Much of the older research—including studies that found more of a protective effect of fruits and vegetables—was done using a case-control method, in which one group (the "cases") already has a condition and is polled about past behaviors and compared with a population that does not have the condition (the "controls"). Many researchers fault case-control work as being a weak method for showing direct causality, especially because it is subject to substantial recall bias.
As Willett noted in his editorial, "This study strongly confirms the findings from other prospective studies that the results of case-control studies were overly optimistic and that any association of fruits and vegetables with risk of cancer is weak at best."
One of the downsides of the new analysis, however, is that researchers only obtained dietary information at the start of the study, with cancer information being gathered through direct patient follow up or official records. This means that if individuals changed their diet much between 1992 and 2000—even if they started eating loads of fruits and vegetables the month after the study started—those changes are not reflected in the final analysis. Boffetta explains that this aspect of the study design could "be an explanation of the weak effect we found. If we had been able to measure properly changes in diet, the measured protective effect might have been stronger."
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Add CommentWith all the insecticides and herbicides used, whatevcr beneficial from fruits and vegetables may be countered by the carcinogenic properties of these chemicals. Many of them are not just surface contaminations which may be washed away. But some are internal.
Reply | Report Abuse | Link to thisYet another example of the failure of both research and communication from the nutritional sciences community.
Reply | Report Abuse | Link to thisIn the elapsed decade or so, a multitude of commodity and grower's groups have ensured a huge market for everything from apples to zucchini based on marginal data and doubtful statistics.
The only real benefit of this wild goose chase is that a whole generation of researchers have kept their labs busy while the general public is fed an intermittent diet of cognitive noise and fraud.
Yet another success for science. Old ideas are overturned by new data or in this case refined. There are benefits to a diet rich in fruits and vegetables but these need to be quantified better. Especially in these new days of snake oil salesmen where any food producer or supplement make can make the wildest claims about their products with little or no science to back up the claims.
Reply | Report Abuse | Link to thisI *LOVE* this study. I've been a veggie-munching health nut athlete my entire adult life, and when I went through cancer treatment two years ago, guess who my chemo peers were? Other veggie-munching athletic women!
Reply | Report Abuse | Link to thisIf veggies substantially lowered your risk of cancer, it would have been my smoking, alcoholic aunt, and not me, in chemo. I suspect there will be a tad less blaming the victim, or preaching to already-health-conscious cancer survivors after this. To which I say: HURRAY!!! And: about time!
I *LOVE* this study. I've been a veggie-munching health nut athlete my entire adult life, and when I went through cancer treatment two years ago, guess who my chemo peers were? Other veggie-munching athletic women!
Reply | Report Abuse | Link to thisIf veggies substantially lowered your risk of cancer, it would have been my smoking, alcoholic aunt, and not me, in chemo. I suspect there will be a tad less blaming the victim, or preaching to already-health-conscious cancer survivors after this. To which I say: HURRAY!!! And: about time!
I don't think eating more of anything is a good idea unless it is displacing other unhealthy foods. Animal products are great at helping us grow, but they're also great at helping cancer grow. If this were a study on the effects of the percentage of calories consumed from plant and animals sources, then it might have some weight to it. The China Study was likely the most comprehensive census of eating habits and health trends ever undertaken and it showed more than just a small statistical correlation between eating less animal products, eating more plant produce and better health. I would also like to know who funded the research for this article. At lot of research has been done to push the high protein diet and it's all been done by people in the meat/dairy industry.
Reply | Report Abuse | Link to thisIn any case, people shouldn't take this as "it's pointless to eat more veggies because it only barely matters." There are plenty of other reasons to maintain a low/no meat diet.
@Nathaniel,
Reply | Report Abuse | Link to thisI think you're confusing the "eat more veggies" advice with "eat a vegetarian diet". There are numerous studies comparing a high-vegetable omnivore diet with a vegetarian diet, and much of the touted advantage of vegetarian diets disappears when compared to a "5-9" vegetable (with fish and meat) diet. Most of the benefit, not surprisingly, is for people who add veggies to a junk food diet or have other risk factors for chronic malnutrition (smoking, high alcohol consumption, etc).
I read The China Study also, along with many, many other studies on cancer risk, and wasn't impressed. When I see studies of different ethnic population groups and cancer risk, the first question I ask us: sure, and now let's look at genetic variations. Do Asians have the same rate of cancer-promoting genetic mutations as Euros (and it doesn't stop at BRCA)? From another perspective: while Asians have fewer hormone-driven cancers than Euros do, they have many times as much stomach cancer. And, they are more prone to type II diabetes unassociated with body mass (i.e., in skinny people) than is seen in Euros. And then there are the lifestyle issues...
Studies like the China study and the Okinawa Plan book and their ilk take far too narrow a focus of a hugely complex issue. They look at lifestyle factors that fit their agenda (meat vs. veggies) and ignore equally important factors (family and social structures, chronic stress, genes, epigenetic influences, environmental chemicals and pollution, etc). For heart disease risk alone, skim Malcolm Gladwell's book Outliers. There's a stunning study on the impact of social environment (plus genes) and cardiac health pointing to factors other than diet.
Until we know vastly more about all of these factors (all of which have been linked to various disease risks), I just shrug at most epidemiological studies. We're still in the dark ages as far as population risk goes, and are next-to-clueless on individual risk.
@Ungolythe: well stated rebuttal to MadS' flawed logic. While the study does diminish the anti-cancer benefits of a veggie-heavy diet, it does underscore that such a diet IS STILL A BENEFIT! If MadS wants to take this information and switch to an all-meat diet because veggies "no longer prevent cancer", so be it. The less ignorant dimwits in the gene pool the better.
Reply | Report Abuse | Link to thisWhat about the fact that by eating more produce and fewer meat products, a person avoids harmful hormones, antibiotics, and is less likely to become obese or develop diabetes and hypertension? Seems like a good reason to eat more fruits and vegetables to me. And if you're worried about pesticides, eat organic.
Reply | Report Abuse | Link to this@SpoonmanWoS
Reply | Report Abuse | Link to this"The less ignorant dimwits in the gene pool the better." Do you understand what a dimwit this comment makes you look like? Did you read the article? The article didn't say "stop eating vegetables." It only said, very narrowly, that vegetable intake is not strongly correlated with cancer risk. It was silent on any of the other reasons to eat veggies, or avoid them or think of them at all.
You're such a perfect example of ignorant. You have your agenda ('eat vegetarian or die') and you allow it to utterly color your intake of any other fact and deform your judgment. I'd suggest you learn to think, because if nothing else, it will lower your stress -- which is a health risk factor independent of diet.
Chow,
Bubbles
Finally, we have a study that admits changing times and new analysis," protective effect of fruits and vegetables is much smaller than had been believed 10 years ago".
Reply | Report Abuse | Link to thisI love this part because I believe in an integrated approach. Thank you to Walter Willett at Harvard School of Public Health's who wrote an editorial accompanying the study.
People who eat more fresh fruits and vegetables are also more likely to make other healthful lifestyle choices, such as exercising more and drinking and smoking less, which the researchers noted "may have contributed to a lower cancer risk" overall.
thank you to Katherine Harmon for a good and informative article without any hype.
Finally, we have a study that admits changing times and new analysis, protective effect of fruits and vegetables is much smaller than had been believed 10 years ago.
Reply | Report Abuse | Link to thisI love this part because I believe in an integrated approach. Thank you to Walter Willett at Harvard School of Public Health's who wrote an editorial accompanying the study.
“People who eat more fresh fruits and vegetables are also more likely to make other healthful lifestyle choices, such as exercising more and drinking and smoking less, which the researchers noted "may have contributed to a lower cancer risk" overall.”
Thank you to Katherine Harmon for an informative article without any hype.
harriet@youthingessentials.com
praying to jesus cuts down on cancer
Reply | Report Abuse | Link to thisNo, sadly, it has been shown that prayers haven't helped a bit when it comes to cancer- or any other disease for that matter.
Reply | Report Abuse | Link to thisBlaming our bad nutritional habits on bad luck in life isn't very logical, either.
Why not think bio-logical instead and realize that we are the only creatures on earth that eat cooked food! This means: most vitamins are cooked out, and the rest is condensed calories , leading to obesity, with cancer as its first consequence.
This applies equally to vegetarian cooking, hence the poor health statistics!
Incidentally,Dr. David Katz at Yale University devised an "Overall Nutritional Quality Index, in which fruits and vegetables score the highest. Significantly, RAW apples score 96% , whereas something as American as apple PIE ranks at a lowly 2%.
In spite of the fact that a raw apple had rather a bad press in the bible, I' d rather stick to the old adage: an apple a day keeps the doctor(s) away.
For an evolution-based nutrition concept, see: Colour Eating without Heating : youthevity.com
The China Study authors and other researchers have concluded that lifestyle - including diet - more so than genes determine cancer risk. For instance, when members of low-cancer populations eat a typical Western diet, their rates of cancer approach ours.
Reply | Report Abuse | Link to thisOther studies confirm these findings. For example, a large Scandinavian study of twins showed that lifestyle can explain 75 percent of cancer risk; presence of the BRCA family of genes was a much less consequential factor.
The usual caveats apply; e.g., there are always some studies that show, at least superficially, different results. In some cases, studies can be discounted based on who's funding them; for instance the dairy industry has funded studies showing that consuming dairy can help in weight loss, but the predominance of independent studies show a correlation between dairy consumption and weight gain or obesity.
A proper diet of Fruits & Vegetables are beneficial to decrease the cancer risk & your body. Don't over diet of any food it become unhealthier for your health. http://www.medicine2life.com
Reply | Report Abuse | Link to thisA proper diet of Fruits & Vegetables are beneficial to decrease the cancer risk & your body. Don't over diet of any food it become unhealthier for your health. http://www.medicine2life.com
Reply | Report Abuse | Link to thisI am assuming that agribusiness in Europe is similar to the US. With that in mind, the content of the crops there is as poor as it is here. The mono-culture in farming is depleting the soils of the very components that make the crop worth consuming. Rotate crops to allow the soil to recover and replenish. Unfortunately, agribusiness on either continent is only interested in the bottom line, not the health of the customer. The situation has been getting worse for the past 75 years. Check out: http://www.senatedocument264.com/
Reply | Report Abuse | Link to thisMy friends if I may add my comment, nutrition is also a matter of quality of life -no doubt a more vegetables oriented diet will
Reply | Report Abuse | Link to thisfor sure predispose among other things,to a thinner body (avoiding obesity etc),as far as I knew veg diet had proved to be protective for some (not all )neoplastic conditions for example
gastrointestinal,so basically that may give a hand but smoking remains certainly the #1 cause recognized so far...
'Boffetta explains that this aspect of the study design could "be an explanation of the weak effect we found. If we had been able to measure properly changes in diet, the measured protective effect might have been stronger."'
Reply | Report Abuse | Link to this- assuming that twenty years of propaganda has induced people to eat less and not more vegetables and fruit.
If, on the other hand, the prop has made people in the study eat more vegs and fruit over the years, then the effect is even weaker than the study has found.
In response to the "eat only raw foods" post:
Reply | Report Abuse | Link to thisThere is a very good reason to eat cooked foods - Parasites! Most human feeding parasites are transmitted from plant sources rather than meat. Cooking kills them. I'll pass by the opportunity to get tapeworms, thank you very much!
Food poisoning does seem to come mostly from uncooked or old meat but again, cooking kills that too( except for the botulism toxin). I gave up most meat after developing heart disease and now really dislike the taste. I do not, however think meat in moderation is particularly bad because the average life span and quality of life continues to increase.
The Best way to fight Cancer is by spreading cancer awareness. Though most citizens of developed countries know about cancer, but the third world developing nations are too far behind when it comes to cancer awareness. They still tend to follow there old ways of life and some even try to treat cancer using spiritual and other out of the world things.
Reply | Report Abuse | Link to thisMost forms of cancer can be cured if diagnosed early, but often we tend to be negligent which at times can be life threatening. If we find anything abnormal in our body then we should approach a qualified doctor.
So please remember, to fight cancer you have to diagnose and treat it as early as you can.
Ive take a small initiative on my part in the form of :
<a href=" http://www.cancery.com"> http://www.cancery.com</a>
Would request you all to spread cancer awareness, make people around you realize the need of early diagnosis.
The Best way to fight Cancer is by spreading cancer awareness. Though most citizens of developed countries know about cancer, but the third world developing nations are too far behind when it comes to cancer awareness. They still tend to follow there old ways of life and some even try to treat cancer using spiritual and other out of the world things.
Reply | Report Abuse | Link to thisMost forms of cancer can be cured if diagnosed early, but often we tend to be negligent which at times can be life threatening. If we find anything abnormal in our body then we should approach a qualified doctor.
So please remember, to fight cancer you have to diagnose and treat it as early as you can.
I’ve take a small initiative on my part in the form of :
<a href=" http://www.cancery.com"> http://www.cancery.com</a>
Would request you all to spread cancer awareness, make people around you realize the need of early diagnosis.