07 April 2010

Another Huge Study Finds Little Benefit From '5-a-day'

Supports Chapter 8: Why 'Five Portions'?

You may have heard on the news today about this latest study, which didn't find much benefit from forcing five portions of fruit and veges down. I was not surprised as all the ones before it are detailed in Chapter 8 of Trick and Treat. But it was good of the media to report it. 'Bad news' like this is generally missed.

There have been several studies since the '5-a-day' message was first trumpeted. None so far has found much, if any benefit from eating so much vegetation. This latest one is by far the biggest - but its findings are much in line with the earlier studies.

Wouldn't it have been better if the diet dictocrats had thought to do a study before they told us all to eat so much!

The abstract to the latest study is below.

I have written a full article explaining why it's NOT a good idea to eat 5-a-day.

* * * * * *

Paolo Boffetta, et al. Fruit and Vegetable Intake and Overall Cancer Risk in the European Prospective Investigation Into Cancer and Nutrition (EPIC) JNCI 2010 [e-pub ahead of print]



ABSTRACT
Background: It is widely believed that cancer can be prevented by high intake of fruits and vegetables. However, inconsistent results from many studies have not been able to conclusively establish an inverse association between fruit and vegetable intake and overall cancer risk.

Methods: We conducted a prospective analysis of the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort to assess relationships between intake of total fruits, total vegetables, and total fruits and vegetables combined and cancer risk during 1992–2000. Detailed information on the dietary habit and lifestyle variables of the cohort was obtained. Cancer incidence and mortality data were ascertained, and hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression models. Analyses were also conducted for cancers associated with tobacco and alcohol after stratification for tobacco smoking and alcohol drinking.

Results: Of the initial 142 605 men and 335 873 women included in the study, 9604 men and 21 000 women were identified with cancer after a median follow-up of 8.7 years. The crude cancer incidence rates were 7.9 per 1000 person-years in men and 7.1 per 1000 person-years in women. Associations between reduced cancer risk and increased intake of total fruits and vegetables combined and total vegetables for the entire cohort were similar (200 g/d increased intake of fruits and vegetables combined, HR = 0.97, 95% CI = 0.96 to 0.99; 100 g/d increased intake of total vegetables, HR = 0.98, 95% CI = 0.97 to 0.99); intake of fruits showed a weaker inverse association (100 g/d increased intake of total fruits, HR = 0.99, 95% CI = 0.98 to 1.00). The reduced risk of cancer associated with high vegetable intake was restricted to women (HR = 0.98, 95% CI = 0.97 to 0.99). Stratification by alcohol intake suggested a stronger reduction in risk in heavy drinkers and was confined to cancers caused by smoking and alcohol.

Conclusions: A very small inverse association between intake of total fruits and vegetables and cancer risk was observed in this study. Given the small magnitude of the observed associations, caution should be applied in their interpretation.


CONTEXT AND CAVEATS

Prior knowledge

The association between high intake of fruits and vegetables and reduction in overall cancer risk is not conclusively established.

Study design

European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study was conducted between 1992 and 2000. Diet and lifestyle data were self-reported by the participants. Cancer incidence and mortality data were obtained from country-specific national and regional registries. Association between overall cancer risk and high intake of total fruits, total vegetables, and total fruits and vegetables combined was assessed. Estimated cancer risks were adjusted for smoking, alcohol consumption, and many other variables.

Contribution

High intake of vegetables, and fruits and vegetables combined, was associated with a small reduction in overall cancer risk. The association was stronger in heavy alcohol drinkers but was restricted to cancers caused by smoking and drinking.

Implications

This study reveals a very modest association between high intake of fruits and vegetables and reduced risk of cancer.

Limitations

The inverse association between overall cancer risk and high intake of fruits and vegetables was weak. Errors inherent to self-reported dietary habits may have resulted in bias.

51 comments:

Anonymous said...

Hi Barry,

Have you any idea of how this belief in the protective effects of fruit and veg came about or who started saying that we should eat five portions? Apart from the Vitamin C content, I have no idea why.

Steve

Barry Groves said...

Hi Steve

Someone, I have no idea who, just made it up. I think I know why.

My sister, a psychologist, always tells me that, to get a book to sell, it has to have 'magic', by which she means something catchy.

'5 portions of fruit and veg' is catchy; it is easy to memorise, it has a ring about it. So '5 portions' it is.

But as the article on my website shows shows, there isn't any evidence for it! And this is admitted by the Medical Director of the British Heart Foundation who push the dogma, a couple of paragraphs further on.

'5 portions' is born of nothing more substantial than wishful thinking.

And it is just as harmful as pretty much everything that emanates from government health quangos in my eopinion.

Barry

ET said...

Let me get this straight. Eating one banana, a piece of watermelon, and a big potato is as healthy as eating one serving each of broccoli, tomatoes, squash, green beans, and strawberry.

Catchy little phrases like "5-a-day" do more harm than good. It encourages people to dump a lot of easily digestable carbs into their bodies. But hey, most other dietary advice is also wrong.

Anonymous said...

Hello Barry,

Is grain-fed, factory farmed (hormone and antibiotics given) beef OK as the only meat source, eaten daily, in your opinion?

I'm on a limited budget so I cannot afford certified organic, 100% grassfed..

Matthew Shipton said...

My irritation is derived from the conceptualization of fruit sugars, fructose, as being from fruit, and therefore healthy. Vegetarians and health food zealots try to wield this fact like a spear despite the fact that fructose is one of the most lipogenic of carbohydrates and also places metabolic load on the liver.

How ignorant are they to ignore that 50% of table sugar is this "natural, healthy" sugar?

Anonymous said...

..."that fructose is one of the most lipogenic of carbohydrates and also places metabolic load on the liver..."

How is fructose more lipogenic than sucrose? Why?

Can you explain the bit about the liver please?

Steve

Matthew Shipton said...

Certainly - as soon as I have time I'll find where I got it from.

My apologies if I'm incorrect, but regarding sucrose, I believe it goes that fructose is unable to cause an insulin reaction or something of the sort, so when coupled with glucose, i.e. sucrose, it becomes very lipogenic.

For interest's sake, it's from the book 'Good Calories, Bad Calories' by Gary Taubes.

Matthew Shipton said...

I don't seem to have Mr. Taubes book with me in my current location so when I find the appropriate passage I will post it for your reference.

In the meantime, hopefully I can supplement you with something:

(regarding fructose and the liver):
http://en.wikipedia.org/wiki/Fructose#Fructose_metabolism

On the same page, if you scroll down to health effects, are sections that touch on what I said regarding its lipogenic properties.

These sources of course are only as strong as the sources they reference, so by all means scrutinize them where possible.

Matthew Shipton said...

Dr. Groves,

Regarding this talk of the Framingham study, something we hear little of is its analogue in Busselton, Australia. What are the results of that study saying?

Thanks,
Matt

Barry Groves said...

There are several different sugars with the formula C6 H12 O6. The differences come from the way the atoms are aligned. Fructose (called 'laevulose' because it refracts light to the left) is a mirror image of Glucose (called 'dextrose' because it refracts light to the right) and that has a very significant impact on our bodies.

Glucose can be and is used as a fuel for the body; fructose cannot. Its atoms have to be rearranged from fructose into glucose before it is of any use. And that is a difficult biochemical task for the liver. I have added some references below that you can look up to see the wide range of medical conditions attributed to eating fructose. It may be of interest that the earliest one (Beard, 1911) hypothesised that laevo-sugars were the cause of cancers. It wasn't until 1931 that Otto Warburg was awarded the Nobel Prize for a hypothesis which seems to back up Beard's hypothesis.

Busselton
Framingham scores used to assess CHD risk are based on data from the US, on age, blood pressure, anti-hypertensive medication, total and HDL cholesterol, smoking, diabetes, left ventricular hypertrophy and previous history of CHD. The Busselton study was set up to check that the Framingham scores applicable if Australian data were used. It found it was.

Barry

Fructose references
Metabolic syndrome (Obesity, diabetes)
Hallfrisch J. Metabolic effects of dietary fructose. FASEB J 1990; 4: 2652-2660.
Swanson JE, et al. Metabolic effects of dietary fructose in healthy subjects. Am J Clin Nutr 1992; 55: 851-856.
Elliott SS, et al. Fructose, weight gain, and the insulin resistance syndrome. Am J Clin Nutr 2002; 76: 911-922.
Nakagawa T, et al. Hypothesis: fructose-induced hyperuricemia as a causal mechanism for the epidemic of the metabolic syndrome. Nat Clin Pract Nephrol 2005; 1: 80-86.

Other diseases (Heart disease to gout to cancer)
Beard J. The Enzyme Treatment of Cancer and Its Scientific Basis. London: Chatto & Windus, 1911; Chap VI.
Geddes L. Watch out for the wrong kind of sugar. New Scientist 2008; 2662: 9.
Johnson RJ, et al. Potential role of sugar (fructose) in the epidemic of hypertension, obesity and the metabolic syndrome, diabetes, kidney disease, and cardio-vascular disease. Am J Clin Nutr 2007; 86: 899-906.
Edwards HT, et al. Human respiratory quotients in relation to alveolar carbon dioxide and blood lactic acid after ingestion of glucose, fructose, or galactose. J Nutr 1944; 27: 241-251.
Brown CM, et al. Fructose ingestion acutely elevates blood pressure in healthy young humans. Am J Physiol Regul Integr Comp Physiol 2008; 294: R730-737.
Nothlings U, et al. Dietary glycemic load, added sugars, and carbohydrates as risk factors for pancreatic cancer: the Multiethnic Cohort Study. Am J Clin Nutr 2007; 86: 1495-1501.
Choi K, et al. Fructose intolerance: an under-recognized problem. Am J Gastroenterol 2003; 98: 1348-1353.

Barry Groves said...

Sorry, Anonymous, I didn't answer your question on grain-fed beef.

I do not believe that grain-fed beef, with its attendent prroblems both to the cattle and to us, is a suitable food. If you cannot source your beef from a farmer's market, where you can quiz the farmer and discuss how his cattle are fed, I suggest it might be better to buy New Zealand lamb. While not necessarily 'organic' it is practically certain to be grass fed.

Barry

Anonymous said...

Thanks Matthew and Barry for all that info. Suddenly all my old biochem lectures came flooding back to me!

I became a bit suspicious of fruit many years ago when my old teacher pointed out that most of them are just designed to get the seeds spread as far as possible and deposited on the ground in a nice pile of healthy dung. i.e. just like showing a child a brightly colured sweetie. Tastes delicious but of no use to you whatsoever.

Steve

lightcan said...

Thank you Dr. Groves for the article on the 5-a day and for all the references given above. I find that your information is particularly compelling because you can go back in the history of medicine and look at the evidence from the whole of the 20th century, not only at the most recent studies.
Half an apple taken with dinner (see immune system and fructose) OR some tomatoes a day it is. Just for pectin.
Berries are not in season yet.

Nightingale said...

Dear Dr Groves,

Are berries OK? Sometimes the chemo treatments ruin my appetite, and the only way I can get calories in, and prevent too much weight loss is to make a "smoothie" with whole fat yoghurt, protein powder, and frozen berries. I don't make a steady diet of it, but it helps.

Also I was told that pork is not a suitable meat, because pigs don't sweat, and therefore keep "toxins" in their bodies/meat. I'm not quite buying that one. And thoughts?

Anonymous said...

Berries are quite alright and may I suggest you add cream to your dish of berries - if you can tolerate it? It greatly helps with the calories. Forget about the pig myth. Pigs may not be able to sweat but if they couldn't rid themselves of toxins how would they survive without dying from their own toxins? Pork-bashing has become quite a fashion among some people and pig meat has been accused of all sorts of things. There was this German doctor (Dr. Reckeweg) who wrote a whole tract about the evils of pigmeat - it was supposed to congest vital organs and cells if I remember correctly. All balderdash.

Barry Groves said...

Hi Nightingale

Anonymous has just about covered it.

The only thing I would add, is to drop the protein powder. These powders have been shown to increase the risk of osteoporosis, among other things. Much better to get yout protein from real food.

Barry

Nightingale said...

THANKS anon and Dr Groves. Anon, I have, in fact, been using organic heavy whipping cream with my berries for a snack. Since I started doing that about a year ago, I haven't been able to eat ice cream...too sweet.

Dr Groves I will stop the protein powder. Even at my worst, a scrambled egg with cream is palatable. Interestingly, my Siamese cat always knows when I'm cooking with butter, and waits patiently until I'm finished eating so she can lick the plate. Ever since she started doing this, her fur coat has taken on a particularly lovely sheen.

Matthew Shipton said...

Dr. Groves,

What is your opinion surrounding implications of cancer and candida albicans?

Thank you!

Matthew Shipton

Barry Groves said...

Hi Matthew

I'm unsure, is the brief answer.

Candida is found in all peoples, even those who eat a traditional diet and have had no contact with civilisation. In almost all people it causes no problems at all. However, it can become a problem with many different manifestations and symptoms. Cancer is one suspected one.

The real question now, I think, is this: Is the candida the cause of the cancer? Or is a sugar rich diet, which causes candida to become problematical, the cause of both?

I suspect the latter, but I have no hard evidence to support that belief, other than the work of Otto Warburg and others which have demonsttated that cancers need us to eat a high-sugar diet for them to grow and spread.

Either way, the two (candida and cancer) do seem to go together - or is it just the case that all cancer patients will have candida, because we all have candida, whether we have cancer or not?

I suspect your guess may be as good as mine.

Barry

PokCalaway0710 said...

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Ann said...

Interesting article, but your anti-vitamin bias is pretty obvious. It's a shame that you had to rely on a typically flawed drug study to support your assertions that isolated vitamins are of no use or even dangerous.

Peter.

Anonymous said...

Ann, or er...Peter...???

Are you an ex spin-doctor for Blair or Berlusconi?

Do we win a prize if we have the slightest idea of what you're talking about?

What anti vitamin bias?

References please!

Steve

Matthew Shipton said...

Hi Barry,

Important question. Recently I turned my dad over to following a high-fat diet. However, he noted mild GI discomfort a few hours after meals. He recently revealed to me that he had his gall-bladder removed in 2005 (he is currently 61). Would this present any issues? If so, what could he do to work around it?

Thank you,
Matthew

Barry Groves said...

Hi Matthew

Bile is made in the liver for the emulsification of dietary fats so that they can be digested and absorbed from the gut. And the liver makes bile continuously. This is normally stored in the gallbladder until it is needed (a fatty meal).

Having the gallbladder removed means that the storage facility is no longer there. However, the bile is still manufactured and there is still some storage possible in the bile ducts.

In practice, what this means is that there will still be some bile available to help with the digestion of fats, but not as much as there should be. For this reason, your father can still eat fats, but might have to limit the amount eaten at any one time, and perhaps spread them out over the day more than he otherwise would.

In the event of getting a diagnosis of gallstones I think it's a good idea to try a liver flush (Google the term) to get rid of them if possible, before succumbing to an operation. That gallbladder is there for a reason.

Barry

Anonymous said...

Barry please reply to my email I sent you through the email on your secondopionions website! I've been waiting eagerly for your reply! Thanks =) Lucie

Barry Groves said...

Hello Lucie

Would you resend your email, please. I have no record of having received it.

Barry

Luddite said...

Hi Barry,

For years, on my doctor's advice, I have kept out of the sun due to a large brown mark on my face, which was covered in no fewer than nine seborrhoeic warts. I never went out with out a hat and loads of sun factor. I decided to follow your advice and since mid-April, I've been sitting out in the sun at midday during my lunch break with no protection. To my amazement, the warts dried up and fell off, and now the brown mark is fading, and the skin is beautifully smooth. I have had this unsightly mark since the mid-1970s and I am so pleased it has started to fade.

I'm now hoping some of the scaly patches on my arms and legs will disappear too.

The only disadvantage is that my skin is colouring up and my mild impetigo shows up more! It's a small price to pay.

-Jean.

Luddite said...

And I didn't mean impetigo at all - it's vitiligo that I have! (Brain fog too).

Barry Groves said...

Hi Jean

Delighted that most ailments have cleared up. On the vitiligo, if you have small patches of light skin, which also tend to be scaly, it could be a sign of vitamin B-12 deficiency.

If you eat a diet such as I recommend, a B-12 deficiency might seem unlikely. However, for vitamin B-12 to be absorbed your stomach has to produce 'intrinsic factor'. Many people don't produce enough. Might be worth checking with your doctor.

Barry

Luddite said...

Hi Barry,

The white patches aren't scaly at all. The scaly patches are darker than the surrounding skin. I did ask my doctor about both problems but all he suggested was using moisturiser.

-Jean.

Anonymous said...

Hi Jean,

your doctor suggested moisturiser? Here's an expert for you. Some doctors have to be treated like bacon: grill them...

Victor said...

Hi Barry,

I've been reading your site regularly for a little over 2 years now. I think it took me a good year of understanding the literature before I undid the brainwashing of modern nutritional guidelines and switched to the natural human diet.

I'm thinking about buying half a grass-fed cow which will probably be about 200 lbs beef. The butcher will vacuum seal the beef right after it's cut. I have talked to people who have bought half a cow before and they say the taste is still good after several months and there's no freezer burn. What do you think about the beef's nutritional quality after being frozen for several months? Does the nutritional quality significantly decrease even if the flavor is still there?

Thanks for your help, Barry.

-Victor

Barry Groves said...

Hi Victor

Wow, you lucked out big time.

You need have no worries. The meat will keep for a year or more if the freezer is cold enough; and there shouldn't be any appreciable nutrient loss.

Enjoy!

Barry

Matthew Shipton said...

Hi Barry,

I thought I would bring the following study to your attention in case you hadn't already seen it, as I've now run across a few websites using it as evidence that high fat diets are linked to diabetes, of all things.

http://www.ncbi.nlm.nih.gov/pubmed/12643169

Sincerely,
Matthew

Barry Groves said...

Hi Matthew

Unfortunately, I don't subscribe to this journal. However, it is normal in US trials to lump natural saturated fats from animals and tropical oils together with hydrogenated vegetable oils, and then call them all 'saturated fats'.

This leads to quite erroneous results as the two types of fats are quite different.

Hydrogenated vegetable oils have been shown to increase insulin resistance[1] - but animal fats have not. Which is probably why diabetes was rare or non-existent until we started to eat processed margarines at the beginning of the last century, and why 'primitive' cultures who do eat animal fats and tropical oils, don't get diabetes even today.

In my opinion, studies like this one only serve to show the level of ignorance there is in the researchers.

1. Pan DA, et al. Skeletal muscle membrane lipid composition is related to adiposity and insulin action. J Clin Invest 1995; 96: 2802-2808.

Barry

Brian said...

Yes Anon it was my mate who started it off, he owns fruit n Veg shop down the road.

Joking aside

From what I have read in last few months, it has more than likely came from people whom prosper from it, either by being in the trade or by people having a nice vacation from the people in that trade.

Gerandia said...

I heard the idea of the 5 fruit of veg a day was helped to push our fruit and veg farmers sell more.

Love your blog and site. I use it for good ammunition because so many doctors seem to follow the party line

Barry Groves said...

Hi Gerandia

That's as good a reason for the government to recommend something as any other.

Thanks for the compliment. Keep shooting

Barry

Luddite said...

Hi Barry,

My husband is a diabetic who has managed to cut down on his meds and improve his blood sugar control by following your recommendations over the last 5 months.

However, he has just been diagnosed with lipodermatosclerosis (after 3 years of mis-diagnoses) and he is getting earache from the dermatologist about his diet.

Do you know of any reason why someone with this condition should go low-fat? Or is it just mainstream medical bias to push low-fat high-carb diets?

If you have any recommendations, I'm all ears - he's in so much pain with what is now quite an advanced condition.

-Jean.

Barry Groves said...

Hi Jean#

In a word: No! There is no evidence that fats play any part in lipodermatosclerosis, or that lowering fat intake will be beneficial.

The causes of lipodermatosclerosis are unknown, officially. However, most venous conditions of a similar sort, such as varicose veins, leg ulcers, etc, come about as a result of eating a 'healthy' diet. People who are overweight, diabetic, etc, tend to be the sufferers. Thus it would be more likely that cutting carbs and eating more fats would be beneficial.

Barry

Luddite said...

Thank you, Barry, for putting my mind at rest.

Prior to the start of this year, he did spend almost 10 years following a 'healthy' diet with masses of fruit, pasta and other carbohydrates. All that happened was that he put weight on and his diabetes got worse.

Since following your guidelines, his diabetes has improved beyond all expectations.

For my own chronic problems (fibromyalgia, myofascial pain syndrome and chondromalacia), I've only seen a tiny improvement, but my severe arrhythmia has completely vanished!

-Jean.

Anonymous said...

Hi Dr. Groves

I tried to 'like' you on Facebook, but then someone reported the group as being fraudulent because they thought I was masquerading as you.

So facebook deleted the group and ipso facto told me I can't like you.

WTF

-Brent

Barry Groves said...

Hi Brent

I was the one who reported it as a fraud, because it was. I did not set it up and had no control over what was put on it.

I didn't have a Facebook page and, although I have now, I will probably deactivate it soon as I can't see any use or merit in having it. And, as Facebook can obviously be used for identity theft, I think it could be dangerous to have any contact with the website. I certainly wouldn't put my personal details on it - real date of birth, mother's maiden name, my address, for example.

Barry

Keith Thomas said...

I am presently reading "Trick and Treat" and "Natural Health and Weight Loss" in parallel. There is fantastic information in them and I have quoted a couple of paragraphs from them on my website
(see here for example:
http://www.evfit.com/ev_health_principle.htm#note13)

Thanks for distilling your >20 years of research for us. I hope the book sales are going well and in my quotations from your work, I'll be encouraging people to get the books.

On another matter, you are wise to keep off FaceBook. We none of us need another excuse to spend more time on our computers - let alone the other risks you allude to.

Victor said...

Hi Barry,

Do you consider it safe to eat undercooked (pink, boderline raw) pork and chicken? I regularly eat rare and occasionally raw beef so I'm not afraid of that, but all the talk of worms and salmonella does make me concerned about the white meats. Likewise, what do you think about undercooked game like deer?

Thanks for your advice last time about freezing grass-fed beef. While it is impossible to avoid fluoridated water here, we do have access to grass-fed beef, eggs from a real farm, and raw dairy (including raw cream!).

Thanks again Barry.

- Victor

Barry Groves said...

Hi Victor

We should all be able to eat meat from any healthy animal raw. Let's face it, we must have done that for much of our existence. Game meat, if it was healthy when killed, should be safe to eat. Even road kill, if you know its provenance, should also be fine. Indeed I know several people who thrive on roadkill. The risks, as you have identified, are tapeworms in uncooked pork and bacterial infection in shop-bought poultry.

with tapeworms, both pigs and humans are required for their reproductive process. These days, it is much less likely, I think, to get tapeworms, as pigs are unlikely to pick up tapeworm sections from an infected farmer's faeces and, thus, we are less likely to get tapeworms from eating farmed pigs.

Poultry is a different matter. Because of the factory-farming methods used, infection from bacteria, both in the farming process and the slaughtering/packing process, almost guarantees bacterial infection. For this reason, chicken is the one meat I try to avoid when eating out. And I certainly wouldn't eat it undercooked.

Barry

barbara said...

I heard this on Cnn News this morning. Could someone help me understand this?
http://pagingdrgupta.blogs.cnn.com/2010/09/06/animal-based-protein-diets-increase-mortality-rate/?npt=NP1
Thanks in advance.
Barbara.
Love the book , btw

Barry Groves said...

Hi Barbara

The major problem with scientific research these days is the enormous cost involved in these studies. For this reason, such studies are milked for everything the researchers think they can get out of them.

Don't read too much into this latest publication. It is based on a data dredge of the long-running Nurses Health Study. This is based on a food frequency questionnaire which asked what people ate in general, and was only asked once every two years. Such questionnaires are notoriously inaccurate, and cannot be relied upon.

Indeed, if you look at other reports over the years from this same study, you will find that researchers have come to the opposite conclusions in the past. For example:
"Our data do not support the hypothesis that a high protein intake increases the risk of ischemic heart disease. In contrast, our findings suggest that replacing carbohydrates with protein may be associated with a lower risk of ischemic heart disease." Hu FB, et al. Dietary protein and risk of ischemic heart disease in women. Am J Clin Nutr. 1999;70:221-7.

Barry

pammi said...
This comment has been removed by a blog administrator.
MB said...

Hi Barry,

isn't it a bit harsh to bin a message only because a study (with certain debatable points) showed little gain from high veg&fruit intake ? For instance how was the basic intake established , that they could count those extra hundreds grams /day ? Are all vegetables & fruits equal?

The Asian cuisine is quite rich (&varied) in vegetable intake, and I understood the rate on certain cancers is quite low.

Vegs&fruits offer also a good source of fibers - I don't think these fibers should come only from cereal bran. The first message here also pointed to vitamin C.

... on the Candida subject - I was fighting for some time certain upsetting symptoms, unaided by the usual pharma fix, and after switching on a more anti-Candida diet - which includes lots of vegetables (and less sweet fruits :o) I felt really great . The connection with certain cancers I suspect could come from the constant inflammation given by an overgrowth of Candida (alcohol, acetaldehide, CO2, certain chemotactic substances are secreted by the fungus.. a real "soldier" in other words, probably we have some benefits since we are tolerating it for millions of years ; the problem is when it goes rogue - in the case of sweet-rich diets, antibiotics, estrogen, and people who don't chew too much :-)

To come back to the subject, maybe it would fairer to stress that 5-a-day is too generic, and needs more investigation ?

Barry Groves said...

Hi MB

You make some good points:
1) No, all fruit and vegetables are not equal. Fruit contains fructose, which an increasing number of studies shows in not healthy. Vegetables, on the whole, don't.

2) Asians have low levels of some cancers, but we have low levels of others. Then there are peoples who eat their traditional diets - whether animal or plant based - don't have any cancers.

3) Yes, fruit and vegetable fibre is better than cereal fibre. But that said, many peoples live healthily while eating no fibre at all.

Candida is a condition brought on and sustained by eating a diet containing large amounts of sugars (not just the white stuff). All sugars are derived ultimately from plant foods, particularly fruits, root vegetables and cereals.

You are right that lumping all non-cereal plant materials together in the one recommendation is ridiculous and, yes, more investigations might be useful. But as things stand, there is no evidence as far as I am aware that eating '5-portions-a-day' is of any significant benefit. The bulk of the evidence suggests rather that eating that much might cause harm.

Barry