Eggs, prostate cancer, and the Daily Mail


Our friends at The Daily Mail in the UK have been spreading a story that men who eat 2.5 eggs or more a week have an 81 per cent increase in their risk for lethal prostate cancer compared to men who do not. We assume that this is helping to sell newspapers. The scientific evidence appears to be limited.

To date, we have not actually been able to track down either the original media release or the original study from which The Daily Mail managed to extract this critically important new piece of information! Since one or other must exist somewhere, we can at least take some pleasure from the fact that the majority of the media did not consider this to be a particularly likely or well-validated news story. The Daily Mail provided no source for its initial report. [Ed.: See comments below for information about the original source material for the article in the Daily Mail and related commentary.]

Supposedly, the evidence comes from yet another analysis of data from the Physicians Health Study, which has been going on under the auspices of the Harvard School of Public Health for much of the past 20+ years. Some of the data that had come out of this study has been interesting and thought-provoking. Some of it appears to be of very dubious merit.

In this particular case the “evidence” that eating more than 2.5 eggs a week is associated with a large increase in risk for prostate cancer-specific mortality is based on data from 199 men who died of prostate cancer in a total sample size of 27,000. Of these 199 men, just 55 (about 0.2 percent of the total sample) reported eating more than 2.5 eggs per week. What is more, this association appears to take little to no account of a whole variety of other factors that might have also influenced the risk of prostate cancer-specific mortality in these patients.

An article on the web site of the Harvard School of Public Health deals specifically with the issue of egg consumption and the fact that excessive egg consumption may have significant health impact. However, it also states clearly that, “Recent research has shown that moderate egg consumption — up to one a day — does not increase heart disease risk in healthy individuals.”

Since a heart healthy diet is generally considered to be a prostate healthy diet, it does not seem particularly likely that the 2.5 egg story has any great merit … and what is 0.5 of an egg anyway … only the white … or only the yolk?

27 Responses

  1. “… it does not seem particularly likely that the 2.5 egg story has any great merit …”

    As consistent with The Daily Mail itself.

  2. What a bunch of irresponsible rubbish. Again this is all over the news but the details of the study are left out of all the reports I read. I wonder how many other common things could be linked to these men.

  3. “Men who ate the most eggs also more likely to have a poor diet, be overweight, smoke and take less exercise”

    Yup! Must be the eggs…

  4. Great response, Mike. This of course makes me wonder how much of the other stuff in that same article has any value whatsoever (possibly with the exception to the Harvard Study).

  5. I beg to differ with those of you that suggest this is piffle. Their is plenty of evidence that a suitable diet for prostate cancer should minimize if not eliminate animal protein. Take a look at UCSF’s Your Health Matters “Nutrition & Prostate Cancer” including the extensive references; this pamphlet is approved by Peter Carroll on down and recommended to most new patients. To this we can add The China Study by T. Colin Campbell, especially the chapter on prostate cancer, and Dean Ornish’s work on nutrition for prostate cancer.

    As advocates, we have an obligation to recommend the healthiest possible diet and many believe there is one! We should be minimizing if not eliminating the consumption of animal protein. This does not mean we all have to become vegan, but we should be mindful of moderating our consumption of all animal protein — including dairy and eggs.

    And to answer your question, Mike, half an egg may well be the white for a heart healthy diet, since the yolk is heavy in cholesterol; for those of us conscious of managing our disease through diet, the white still contains the protein. While it may amuse some to poke fun at The Daily Mail we could do a lot worse than paying attention to their observation.

  6. Dear Rick:

    I would draw your careful attention to three words (which I have highlit in bold italic type) under the heading Plant Based Diet in the UCSF brochure you refer to:

    “A lifelong commitment to a plant based diet may lower a man’s risk of developing prostate cancer and may also affect the progression of the disease.”

    The Daily Mail was, by contrast, extremely specific, stating that:

    “… men who consume more than two and a half on a weekly basis were up to 81 per cent more likely to be killed by the disease.”

    Eating a plant-based diet with less animal fat and fewer eggs over a lifetime may well have many health benefits. Cutting one’s egg consumption alone is most unlikely to reduce one’s risk of prostate cancer-specific mortality.

  7. We are all aware of healthy diets and everybody in here promotes diets that go beyond just prostate diets.

    We generally do agree with [almost] everything published by UCSF on prostate diets; not all, as, for example, pomegranate juice is rich in sugar and should possibly be replaced by pomegranate pills.

    The discussion above is eggs and prostate cancer. In searching the UCSF paper, the first reference to eggs occurs in the section about Omega-3 and lists DHA-enriched eggs as as DHA source with the recommendation: “Include these healthy fats daily through diet and/or supplements.” The next reference is in the same table for arachidonic acids with a recommendation to reduce or eliminate meat and dairy products — nothing about eggs.

    Recent studies indicate that cholesterol contained in egg yolk only mildly increases cholesterol in your blood level; subsequently most agencies are now saying that two eggs a day are OK; if that is the case, surely 2.5 eggs a week will not do any harm.

  8. I think you are making two points here, Mike — first that a lifelong change in diet is required, and second that a plant-based diet in conjunction with reducing animal fat is required. In both cases we are now just splitting hairs about The Daily Mail article.

    Re the first point, most men do not change their diet until they experience sickness. UCSF encourages a diet change, as do many other institutions, prostate cancer organizations and medical practitioners, knowing this cannot be a “lifetime” change but that a change going forward is deemed to reduce prostate cancer progression

    Second, a plant-based diet that eliminates consumption of animal protein is clearly optimal but starting by eliminating dairy has been observed as helpful. You quote from the section ‘Plant Based Diet’ but prior to that in the italicized introduction, we say:

    — “Scientific evidence suggests that differences in diet and lifestyle [RD: read exercise!] may account for the variability of prostate cancer rates in different countries” (Hebner, Ornish et al. Nutrition & Prostate Cancer: A Monograph from the CaP CURE Nutrition Project).

    — “Good nutrition may reduce the incidence of prostate cancer and help reduce the risk of prostate cancer progression……..”

    Reviewing the citation after the quote you selected, there is a reference to Dean Ornish’s landmark paper from the Journal of Urology on lifestyle and prostate cancer progression. I believe you will find that men who changed their diet and exercised experienced slower progression. Now I am sure Dr. Ornish would be happy to debate with you whether it was attributable to diet, exercise or the combination. If we are true, non-cynical advocates we should be recommending both, not to mention stress reduction, and that clearly includes reducing consumption of dairy.

    I have not read the original research that found a reduction in egg consumption to be so beneficial so I cannot comment on whether it is flawed as you seem to think; I have seen enough research to suggest that animal protein is harmful. My own opinion is that reducing egg consumption is probably like chicken soup — it cannot hurt, even if chicken soup has a little animal protein!!

  9. Mike,

    There are many studies showing a correlation between diet and prostate cancer. Specifically the studies show that lowering consumption of animal protein has an impact on prostate cancer. It has been shown that even men diagnosed with prostate cancer are at lower risk of recurrence if they cut their animal protein intake. That being said, the results are related to total animal protein. So, if a man stops eating eggs, but increases the amount of bacon he eats, it won’t help him much. Bottom line: it’s not about eggs, it’s about animal protein.

  10. After several days of hunting, I have finally been able to find some actual source data for The Daily Mail‘s claim that eating > 2.5 eggs a week is associated with an 81% increase in the rate of prostate cancer-specific mortality (see Richman et al. and an article in Medical News Today).

    This type of retrospective data analysis can not be used to prove anything we didn’t already know, which is that diets high in animal fats over many years are associated with an increased risk for prostate cancer. Data like these are merely “hypothesis generating.” The authors themselves conclude only that “consumption of eggs may increase risk of developing a lethal form of prostate cancer among healthy men.” [Bold italics added for emphasis.]

    Before I stop eating an average of an egg a day (which I have certainly been doing for most of my 60+ years), I’ll need to see some data that are rather more compelling. On the other hand, I rarely eat red meat more than once a week.

  11. Ahah … If you want a detailed analysis of the strengths and weaknesses of this study by Richman et al., have a look at this article on the NetDoctor web site.

  12. First a reply to Wolfgang — eggs are dairy products! Moreover, for prostate cancer it is the animal protein, not so much the cholsterol, that concerns us albeit I do believe I’ve seen studies correlating high cholesterol with prostate cancer. The resident RD in the cancer department, as well as the physicians and researchers, would all recommend you get your omega-3 from sources other than eggs, although they would probably suggest that moderation is the key word.

    Secondly, while we know there is controversy over pomegranate juice, it is not that rich in sugar if drunk in its natural form — just don’t consume the juice cocktail sold in many supermarkets.

  13. In reply to the site master — and thanks for identifying the citation — I know Erin Richman, the lead author of the egg study; she is one of the co-authors of the recent “walking” study, and a good researcher who came to UCSF from Harvard. This study in question is epidemiological and subject to the same weaknesses as many cohort epidemiological studies.

    My earlier point, however, is that this discussion is not about the quality of the study, nor are we focusing on animal fats and cholesterol. My concern is that men understand that diet is an important aspect of managing our disease. Notwithstanding the sitemaster’s anecdotal evidence, and he is fortunate enough not be a card-carrying member of our club, there are plenty of large studies that link consumption of animal protein and dairy to prostate cancer; at least four are cited in the UCSF document.

    As an aside on animal fat and animal protein, I recall a study some 3 or 4 years back that correlated skim milk with more aggressive prostate cancer than low fat milk. I believe the reason attributed was that the skim milk, notwithstanding its lower content of animal fat and cholesterol, had a higher concentration of animal protein from the whey that was added back.

    While we maintain a sense of humor, it is flippant to poke fun at The Daily Mail article without acknowledging that consumption of animal protein is not recommended and that diet is an important, self-regulated element of controlling our disease — along with exercise and stress reduction. We should not be misleading or misinforming those who visit these pages. Going forward, we hope that men like Wolfgang will have learnt from this discussion that eggs are dairy; whether they choose to adjust their diet is their own decision, but at least we have done them a service by informing them.

    As for the sitemaster — may he continue to enjoy eggs for breakfast and remain free of prostate cancer!

  14. Dear Rick:

    As far as I am concerned, the only thing the original article — and this discussion — were ever about was the overstatement by The Daily Mail, as a “fact”, what was actually just a possibility (“may” being the operative word) when originally reported by Dr. Richman and her colleagues. There is and was never any implied criticism of Dr. Richman or the research. The Daily Mail does this sort of thing all the time.

  15. I understand that some groups erroneously include eggs in “dairy products”. It is about time people understand that cows do not lay eggs.

    See this article on About.com, which states:

    Question: Are Eggs Considered Dairy?

    Answer: Contrary to a somewhat common misconception, eggs are not considered a dairy product, which refers to the product of the mammary glands of mammals such as cows, goats, sheep and others, and the products derived thereof. The misconception that eggs are dairy products is often a result of a confusion between the terms dairy product and animal byproduct. While eggs are, indeed, produced by animals and, therefore, an animal byproduct, they are not a dairy product or a derivative of dairy products.”

  16. Thanks for the clarification Wolfram — we stand corrected and I will bring it to the attention of the editors for the next revision; but rather than making this a semantic discussion, we should all focus on the bottom line — eggs are animal protein, and animal protein is not recommended … so “yes, it must be the eggs” — albeit, along with other animal protein.

  17. Mike — There is little sense in arguing the validity of a cohort epidemiological study; we both recognize it does not establish a causal link and has its weaknesses.

    You do say: “Since a heart healthy diet is generally considered to be a prostate healthy diet, it does not seem particularly likely that the 2.5 egg story has any great merit … and what is 0.5 of an egg anyway … only the white … or only the yolk?”

    This is the statement with which i disagree because:

    (1) It is unnecessarily critical of the article that reports the study and has some basis in fact — that animal protein is bad, and
    (2) It may mislead some readers (per their comments above) since it discounts relevance of egg consumption. I agree with you there is an element of Mail overstatement BUT there is also some basis in fact. without the ensuing discussion, the original post would not make readers aware that animal protein should be limited in a prostate cancer healthy diet — and there are differences between the two diets.

  18. Are these discussions helpful for those of us with prostate cancer? I think they are. It puts the subject of nutrition on the front burner.

    This is a wiley disease that can lay asymptomatic for a long while before becoming explosive. As an advanced prostate cancer patient, I’ve seen doctors who have told me that nutrition won’t make much difference, and others who have recommended I actively participate in a “growth arrest program.”

    Most of my time is spent between doctor’s appointments, where I can reflect on my own decisions. I can wade through dueling citations and scramble the evidence to support any preconception. Should I give up hope? or just give up some of my favorite things on the chance that I’ll live longer? What I do may or may not affect my time on Earth, but it sure makes me feel a lot better each and every day believing that what I do makes a difference.

    As individuals we can make our own choices, but as advocates we have a responsibility to encourage behavior that embraces change rather than resignation. Because there is no single mechanism that explains what causes this disease, let’s encourage good health practices. Exercise, cut down on animal protein, and find quality support.

    Whatever the challenges ahead, you’ll be glad you did.

    Jerry C

  19. Dear Rick:

    You may choose to think I implied whatever you like. I didn’t … that was your interpretation of something I never said … but I will defend to the death your right to be wrong in public.

    :O)

  20. OK, back to the subject then.

    The article in The Daily Mail has a statement that, “according to cancer groups” (no reference given), “men who ate the most eggs also more likely have a poor diet, are overweight, smoke and exercise less”. Rick, any truth to that as far as you know and, if so, does this cloud all discussions on the egg consumption? You sidestepped this by stating, “Yes, it must be the egg”. Is it just a protein issue or are secondary effects shadowing the issues? A related question would be: how much protein is there in a single egg yolk compared to a single serving (3 oz) of red meat?

    Thanks

  21. Wolfram:

    I cannot find any statement in the article in The Daily Mail that mentions the views of “cancer groups” on the numbers of eggs eaten.

    There is a sub-head to the article that reads, “Men who ate the most eggs also more likely to have a poor diet, be overweight, smoke and take less exercise,” but this appears to be a piece of information referenced in the original article by Richman et al.

    Is it possible that we are starting to over-analyze this issue? The relationships between diet, lifestyle, and risk for specific diseases are incredibly complicated. Much as we might like to be able to simplify them, it just isn’t justifiable, which is just one of the reasons why the original article was potentially misleading. We are now way into the trees and in danger of forgetting the size of the forest!

  22. True Mike; not sure where the reference to cancer groups came from; it must have been from the reference to The Daily Mail article when I first found that article.

    The reason that this is very important, nevertheless, is the popularity of eggs for at least most Western countries.

    At least we all seem to agree that moderation is the key, though some of our vegan or vegetarian friends might disagree on that as well. Setting guidelines for what moderation means is probably in the area of over-analysis.

    Another comment in the article that nobody picked up so far is the statement: “They found no significant links between the amount of meat eaten and tumours.” This is contrary to what we all would expect. Was the Harvard study possibly conducted in an area that eats more fish to begin with? If the quoted result were for the general US population (including the Midwest and South) where people consume steaks on a regular basis, then all of our theories on meat and prostate cancer would go down the drain. No, I am not suggesting anybody should relax health diets as at least heart health issues are at stake, but I am wondering if you or Rick could comment on that quote.

  23. Detailed information about the two parts of the Physicans Health Study are available on the study web site. As I understand it, the participants were recruited from all over America (see the sections on “Recruitment” for PHS I and PHS II). However, you need to be careful about interpreting “the amount of meat eaten.” That would presumably include “meat” of all types and cooked in all ways.

    I have always believed that the trick is “moderation” in all things edible. Why? Because the risk of cardiovascular mortality is 20 times that of prostate cancer-specific mortality. When we are diagnosed with any specific clinical condition that could impact our personal mortality, we tend to become fixated on the risks assocated with that condition. However, from an epidemiologic point of view, if the goal is simply to stay alive, the functionality of one’s cardiovascular system is going to trump that of any other biologic system with no difficulty at all.

  24. For Wolfram — a couple of responses:

    I was being a tad sarcastic in referencing another post above that scoffed at egg consumption by saying “yes, it must be the eggs!”. IMOP, it is simply the animal protein in eggs that should concern us prostate cancer survivors.

    Your question about protein levels in eggs v. meat is an excellent one and I will follow up with Greta Macaire, the registered dietician at the UCSF Cancer Resource Center. From what I can discover, there are about 8 grams of protein in 1 oz of red meat and 6-7 grams of protein in one egg … so roughly speaking, an egg has about one-third of a 3 oz serving of meat.

    Next, Wolfram, your question about the quote regarding the correlation between meat consumption and tumors — I can throw no light on this, but if you like I can dig up Erin Richman’s e-mail so you can ask her directly; let me know if you would like me to follow up and how to reach you.

    Lastly, I want to endorse that I am strongly in favor of eating whatever gives you pleasure in moderation — you’ll find that stated in my first post in this thread, and repeated a couple of times thereafter.

    One great resource for you, Wolfram, is The Survivors Handbook — Eating Right for Cancer Survival, published by The Cancer Project; from memory this is a site sponsored by a group of physicians recommending a vegan diet — this means their recipes are all vegan, notwithstanding the book has good diet information. You can have them send you a copy via the web site and/or by calling them at 202 244 5038.

    Hope this helps.

    Rick

  25. While everyone is arguing the demerits of animal protein and the risks of protein from meat vs the protein from eggs, a review of the original article might be helpful.

    They suggested the damage may be done by the large amounts of cholesterol or choline -– a nutrient that help cells to function properly -– that are found in eggs.

    Cholesterol and choline are two totally different things. Choline is a member of the B-vitamin family. The body absolutely requires choline to maintain health. Choline is necessary in the construction of cell membranes.

    If we turn the discussion to cholesterol, we have to take into account that different people process cholesterol differently. Some people can eat massive amounts of cholesterol-laden foods and maintain cholesterol levels well below 200, while others can live on a near-vegetarian diet and still have cholesterol levels above 200. Cholesterol is also necessary to build and maintain cell membranes.

    The bottom line is that the article is so ambiguous that it hardly merits extensive serious discussion.

  26. Any late reports as to egg whites alone are as detrimental as the whole egg?

  27. The yoke’s on you, Ollie.

    Phil

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