veg health news

follow me at science and crap

2010-12-02T13:30:00.001+11:00

I have abandoned this blog like a lover lost at sea. Follow me instead at http://scienceandcrap.blogspot.com/ for more sciencey and unrelated stuff for as long as I can be arsed this time.

ahem...

2010-03-09T23:54:00.002+11:00

sorry for the lack of posting, I just moved back into the city and had no regular internet for the first month. But now that that is finally remedied, I no longer have much time for researching as I have just started a master's in environmental science. I hope to get one or two items up per fortnight, starting from... next weekend? Maybe???

As the Japanese man on the train said when he accidentally bumped me: "Forgiveness, please!"

Food Techs come up with the ultimate in mock chicken

2010-02-07T12:33:00.005+11:00

Some vegans don't like mock meat, especially if it is too much like the real thing. Not me. I love that stuff. And when this stuff gets on the market, I can't wait to try it. Provided it is produced from environmentally friendly soy, of course.

It Looks, Feels and Tastes Like Chicken, but It's Made of Soy

ScienceDaily (Feb. 5, 2010) — Sure, some delicacies might taste just like chicken, but they usually feel and look much different. Soy meat alternatives, such as the soy burger, have become more popular recently, with increased sales of eight percent from 2007 to 2008. Now, scientists at the University of Missouri have created a soy substitute for chicken that is much like the real thing. The new soy chicken also has health benefits, including lowering cholesterol and maintaining healthy bones.

Fu-Hung Hsieh, an MU professor of biological engineering and food science in the College of Agriculture, Food and Natural Resources and the College of Engineering, is leading the project to create a low-cost soy substitute for chicken. His research, funded by the U.S. Department of Agriculture and the Illinois-Missouri Biotechnology Alliance, has led to a process that does more than just add color and flavor to soy. Hsieh has developed a process that makes the soy product simulate the fibrous qualities of a chicken breast.

"Early tests provided some of the fibrous texture to the final product, but it tasted more like turkey," Hsieh said. "In order to produce a more realistic product, we had to tweak the process and add extra fiber to give the soy a stringy feeling that tears into irregular, coarse fibers similar to chicken."

To create the soy chicken, Hsieh starts with a soy protein extracted from soy flour. The soy then goes through an extrusion cooking process that uses water, heat and pressure while pushing the mixture through a cylinder with two augers.

"This particular soy substitute is different because we are working with a higher moisture content, which is up to 75 percent," Hsieh said. "The high moisture content is what gives the soy a very similar texture to chicken -- in addition to the appearance."

Along with pleasing the senses, Hsieh's soy chicken provides health benefits for consumers. Soy foods contain important nutrition components, some of which help maintain healthy bones and prevent prostate, breast and colorectal cancers. Soy foods also are a good source of essential fatty acids and contain no cholesterol. The FDA has approved a claim that encourages 25 grams of soy protein in a daily diet low in saturated fat and cholesterol to help reduce cholesterol that is at or above moderately high levels.

Hsieh's research has been published in the Journal of Food and Agricultural Chemistry, Journal of Food Science, and Journal of the American Oil Chemists' Society. The next step in Hsieh's research will be to taste-test various texture combinations and make final refinements to the formula.

Pork enhances sex drive???

2010-02-01T12:52:00.005+11:00

Apparently, the president of Argentina doesn't get laid much. So when she did last weekend, she held a press conference and asseverated the value of eating pork, which apparently is what she and her husband did before he finally put out. And unsurprisingly, the Argentine pork producer's lobby was quick to confirm her assertions with some more extraordinarily unscientific claims.

Pork beats Viagra for high spirits in the presidential bedroom
January 30, 2010

BUENOS AIRES: Eating pork is at least as effective as popping a Viagra pill to spice up your sex life, according to the Argentine President, Cristina Kirchner, who claims to have tested the theory.

''Pork consumption improves sexual activity,'' Ms Kirchner informed a surprised gathering of business people at a meeting at the presidential palace.

''This is not a small detail,'' she said at the gathering to announce a reduction in the price of pork.

''Besides, some nicely grilled pork is much more gratifying than taking Viagra.''

Ms Kirchner said she ate some roasted pork over the weekend with her husband, former president Nestor Kirchner, at the couple's retreat in Argentina's southern Patagonia region, with ''impressive'' results.

''We were in high spirits the whole weekend,'' she said, smiling. ''I'm a pork fanatic and I'm not saying this just to impress you, or for self-promotion.''

The head of Argentina's association of pork producers, Juan Uccelli, backed up Ms Kirchner's claims.

People in Denmark and Japan, where pork consumption is high, ''have much more harmonious sexual lives than us Argentines have'', Mr Uccelli said.

Argentines, however, are among the world's most voracious beef eaters, with an annual per capita consumption of between 68 and 73 kilograms.

If this article had appeared anywhere other than the "wellbeing" section of The Age website, it could be ignored; but by placing it under this category The Age are implying that it is true. However I can't find a single scientific study indicating that consuming pork can enhance libido or sexual activity in humans.

As for the claims that nations with higher pork consumption have better sex lives, that is like saying since 90% of Americans believe in god and the murder rate in the US is higher than any other Western nation, believing in god increases your risk of being murdered.

Green leafy vegies prevent carcinogenic effects of aflatoxin

2010-01-28T07:24:00.005+11:00

Aflatoxin is a naturally occurring carcinogen produced by fungi associated with food crops such as corn and legumes. Peanut butter is a product which typically contains very small amounts of aflatoxin, which is regarded as safe at such low doses. However the information on the effects is confusing, since it's impacts are so variable. While known to be fatal in high doses and carcinogenic at lower doses (primarily affecting cells of the liver) tests on animals show it is most harmful to species with inefficient liver detoxification, with hamsters tolerating more than ten times the amount fatal to dogs, and up to twenty times that of pigs and cats.

With this in mind, researchers have turned their attention to human subjects and given them doses of aflatoxin which could be traced by an analytical method called mass spectrometry. They found that the compounds in green leafy vegetables called chlorophyll and chlorophyllin reduced the amount of aflatoxin which was absorbed in the subjects. Interestingly, they point out that this experiment was undertaken because of the unreliability of animal testing (http://www.medicalnewstoday.com/articles/177113.php).

Unfortunately I do not have access to the journal in which this study is published. The abstract is available here, but it says enough to bother me. They only experimented on four subjects, and since this was an "unblinded" study (meaning the researchers performing the analyses knew the treatments each sample was associated with) then there is potential for all sorts of bias in the study. That is not to say that it is biased and unreliable, I just can't say without reading the report whether there are any holes in the work that should be considered.

Anyway, it's not like we need any more reasons to ensure we get plenty of fresh green vegies like brocolli, lettuces and spinach. For more info on aflatoxin, check out the pages here and here.

Women and UTI's: Give up meat or give up sex?

2010-01-21T12:07:00.011+11:00

This report is from my favourite site, Science Daily. It seems the types of E.coli which cause more than 80% of all Urinary Tract Infections (UTI's) in women is found on chicken and other products which may be in your supermarket trolley. Worse still, they found that these are antibiotic resistant strains which appear thanks to the use of antibiotics in factory farming.

Retail Meat Linked to Urinary Tract Infections: Strong New Evidence

ScienceDaily (Jan. 20, 2010) — Chicken sold in supermarkets, restaurants and other outlets may place young women at risk of urinary tract infections (UTI), McGill researcher Amee Manges has discovered. Samples taken in the Montreal area between 2005 and 2007, in collaboration with the Public Health Agency of Canada and the University of Guelph, provide strong new evidence that Escherichia coli bacteria originating from these food sources can cause common urinary tract infections.

The research team is also investigating whether livestock may be passing antimicrobial-resistant bacteria on to humans. This is due to the use of antibiotics to treat or prevent disease in the animals and to enhance their growth, which may lead them to develop resistance to the medication. When animals are slaughtered and their meat is processed for sale, the meat can be contaminated with these bacteria.

Full article here.

The researchers took samples from Canadian women diagnosed with UTI's in two geographic regions, then collected samples from foods sold in supermarkets and restaurants in the same locales. They then analysed the DNA of bacteria found from all samples and compared the genotypes to see if there were food sources of E.coli linked to UTI infection.

They found 3 genotypes in two chicken samples and one honeydew melon dish which were identical to antibiotic resistant profiles causing UTI in the human population. The presence of a pathogen on fruit is attributed to cross contamination with meat or from an individual involved in producing the food, and is not regarded as coming from manure fertilisers (although it may perhaps be difficult to rule this out altogether). They also feel that pork and beef products may be promoting the spread of antibiotic resistant bacteria, but the principal focus of this study was on chicken products. They further believe that contamination from humans was unlikely, I imagine due to the hygiene standards imposed upon workers in the Canadian meat industry.

So why is this happening? For years now, it has been thought that the use of antibiotics to promote growth in factory farmed animals increases the incidence of resistant strains of pathogenic bacteria in humans. This is in line with a foundation of evolutionary theory: any organism with a genetic mutation which increases the likelihood that it will persist will contribute more offspring to the next generation as the other individuals die off before being able to do so. Hence, while antibiotics kill off E.coli in chickens, these antibiotic resistant strains arise by natural selection.

Incidentally, it is not eating the meat which causes the UTI. According to the McGill University press release, the bacteria spreads during sex. Anyway, eating the contaminated meat increases the likelihood of UTI infection as these antibiotic resistant strains will then be present in the lower GI tract, and may then "travel from the anus to the vagina and urethra during sex, which can lead to the infection."

They don't go into any specific details about whether the likelihood of infection is increased or decreased by particular sexual acts. Prudes.

Source: Vincent C, Boerlin P, Daignault D, Dozois CM, Dutil L, Galanakis C, et al. Food reservoir for Escherichia coli causing urinary tract infections. Emerg Infect Dis. 2010 Jan.

DOI: 10.3201/eid1601.091118

Available from http://www.cdc.gov/EID/content/16/1/88.htm

2009- The year in meat.

2010-01-06T23:24:00.003+11:00

I was reading Melbourne Vegan and saw a post to a blog by Erik Marcus called the Year in Meat. Marcus has compiled an array of tales from the meat industry, and since he spent ages on it I think promoting it here is the least I can do to say thanks for the hard work he has put in.

Download a pdf of the year in meat here,
or
read it online here.

Interesting article in The Guardian (UK)

2010-01-05T11:40:00.004+11:00

I saw this article on The Guardian website discussing how pharmaceutical companies sponsor research and the questionable reliability of results which indicate their products are better than their competitor's. However the article begins with a more familiar example, mentioning how research sponsored by the US National Cattlemen's Association showed that the Aitkin's diet may lower cholesterol. This is unreliable because they would never allow any research they funded which found that meat consumption is dangerous to human health to be published.

As it happens, recent research on rodents indicates that a high fat diet such as Aitkin's causes inflammation of the lower intestine. Of course, this is in mice so who knows what it is doing to humans; but for years now there have been studies which identify inflammation as a precursor to colon cancer. The inflammation itself seems to be caused by increased presence of free radicals which induce what is known as oxidative stress. In a nutshell, the free radicals damage cell membranes and the DNA inside them. Colon cancer occurs after a series of such changes (ie mutations) in the DNA of cells in the wall of the intestine.

Just to drive this message home one more time, vegan diets can be high in fat if you are not careful. So go easy on the tofutti cuties!

Sources: Ildiko Erdelyi, Natasha Levenkova, Elaine Y. Lin, John T. Pinto, Martin Lipkin, Fred W. Quimby and Peter R. Holt (2009). Western-Style Diets Induce Oxidative Stress and Dysregulate Immune Responses in the Colon in a Mouse Model of Sporadic Colon Cancer. Journal of Nutrition,139 (11): 2072-2078

Laurie A. VanderVeen, Muhammed F. Hashim, Yu Shyr, and Lawrence J. Marnett (2003). Induction of frameshift and base pair substitution mutations by the major DNA adduct of the endogenous carcinogen malondialdehyde. PNAS 100:14247-14252

Julia Bollrath, Toby J. Phesse, Vivian A. von Burstin, Tracy Putoczki, Moritz Bennecke, Trudie Bateman, Tim Nebelsiek, Therese Lundgren-May, Özge Canli, Sarah Schwitalla, Vance Matthews, Roland M. Schmid, Thomas Kirchner, Melek C. Arkan, Matthias Ernst, Florian R. Greten (2009). gp130-Mediated Stat3 Activation in Enterocytes Regulates Cell Survival and Cell-Cycle Progression during Colitis-Associated Tumorigenesis. Cancer Cell, Volume 15, Issue 2, 91-102.

Sergei Grivennikov, Eliad Karin, Janos Terzic, Daniel Mucida, Guann-Yi Yu, Sivakumar Vallabhapurapu, Jürgen Scheller, Stefan Rose-John, Hilde Cheroutre, Lars Eckmann and Michael Karin (2009). IL-6 and Stat3 Are Required for Survival of Intestinal Epithelial Cells and Development of Colitis-Associated Cancer. Cancer Cell, Volume 15, Issue 2, 103-113.

Vegetarian diet weakens bones according to journalist, but not researchers

2010-01-01T22:48:00.008+11:00

It's raining so I can't go out dumpster diving. And I haven't found any new veg specific info in a while. But a friend recently sent me this email:

"I found this article which says that vegans have weaker bones than omnis/ovolactoveggies. Is it true?"

The article on Google News has the misleading headline "Vegetarian diet 'weakens bones'". It tells of a study which found "practically no difference" between the bone mineral density (BMD) of meat eaters and vegetarians who consume eggs and dairy. However, vegans seemed to have lower BMD than the others. But then, lead researcher Tuan Nguyen said "but the magnitude of the association is clinically insignificant."

Hmmm, clinically insignificant. Doesn't really match the headline, does it?

This study is a meta analysis, where instead of conducting research on a single sample group the researchers pool data from several different studies to create a big picture from these different populations. However the relationship is too weak to say that it is the result of diet, and of course the diets are categorised in the overly simplified manner of "meat eater, vegetarian, vegan" etc which is the flaw common to most nutritional research.

However the comments the authors make in their discussion are very interesting:
"BMD is a complex trait, in the sense that it is affected by multiple environmental and genetic factors. It is therefore unrealistic to expect that any single modification, including dietary change, can result in a significant change in the trait. The complexity and possible interaction between dietary calcium and protein makes it difficult to attribute the modest effect of vegetarianism on bone density to either dietary factor.

All studies included in this analysis were observational; therefore, no cause and effect relation between vegetarian diets and BMD can be drawn from the finding."

So... I wonder what Dr Nguyen thought when he saw the headline?

Source: Lan T Ho-Pham, Nguyen D Nguyen, and Tuan V Nguyen (2009). Effect of vegetarian diets on bone mineral density: a Bayesian meta-analysis. Am J Clin Nutr 90:943–50.

Some news...

2009-11-25T18:02:00.001+11:00

Firstly, I would like to thank the people behind the Pharmacy Technician Certification website who have listed veg health news in the health and nutrition section of their Top 75 Blogs for Vegetarians and Vegans. Please check out the article for info on other health blogs as well as stuff about animal rights, cooking, lifestyle and heaps of other useful things for current and potential vegos.

Secondly, a reader pointed out that a mailing list would be a good way to keep people informed of new posts. So that is what I will do! If you would like to be added to the mailing list send me a say so at veghealthnews@hotmail.com and start receiving updates from… well, the first update.

Thanks again for all your support and emails. I’m busy with some early summer tasks but there is plenty of stuff in the works, so I’ll have some new info up by mid-December at the latest. Until then, keep watching what you read.

Grey.

More good reasons to buy fish oil (or not)

2009-10-31T00:21:00.006+11:00

If you are like me, then you are over being told that fish oil will save the world. The oils from oily fishes are high in the long chain omega 3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). DHA is thought to be essential to good health in humans, with implications for brain function in particular.

But time and again you will see research presented as though there is no other possible source for DHA than fish oil. Of course, humans make our own DHA from the shorter chain fatty acids like LHA which are abundant in plant foods such as flax seeds (aka linseeds), walnuts and countless other goodies. But there is a problem, we don't convert LHA to DHA very efficiently. So, enter the knight in vegan armour; algae. Algae is the source of the DHA in fish, can be cultured in a lab; and is hence a sustainable source of nutrients (unlike fish, which is completely unsustainable). So why not cut out the middle man? I get my DHA from a product called Udo's Choice and I mix 1 tablespoon in with a fresh fruit/vegetable juice for breakfast.

Anyway, the latest research shows that DHA is converted to a chemical called Resolvin D2 which is good for your joints and helps prevent inflammation caused by arthritis etc as stated by the articles here, here and here. So if you've got joint problems, or are worried about developing Alzheimer's disease, seek out an algal source of DHA.

Trans fats can't be avoided?

2009-10-28T17:43:00.004+11:00

I found this blog from an Australian news service today. Paula Goodyer dissects some information from the Food Standards Australia New Zealand report on trans fats. For Aussie producers, there are no compulsory labelling laws regarding the addition or quantities of trans fats in processed foods. PG gives some reasonably good info on what trans fats are and questions why we don't have laws to ensure we are informed about this ingredient when other developed countries do.

But it's this comment in the brief FAQ that got me:

"Is there a safe level of trans fats? According to the World Health Organisation, there's no safe level - but it's impossible to avoid them altogether because they're found naturally in beef and dairy products, says (dietitian Susan Anderson, of the Australian Heart Foundation)."

Hmmm, so how does that make them impossible to avoid? A natural diet which abstains from processed foods, meat and dairy products is not feasible?

It is true that trans fats appear in many vegan products. They are necessary to produce things like vegan margarines, cheeses etc without animal products. But does this mean they can't be avoided? No, it doesn't. I know plenty of people who don't eat that stuff, precisely because they want to avoid trans fats.

WHO/FAO review of dietary fats and cancer.

2009-09-22T11:52:00.007+10:00

Been a slow couple of months for vego nutrition studies in the news! But here is something which affects us all. The World Health Organisation and the UN Food and Agriculture Organisation have been working together looking into the research on the effects of fats in the diet. I had a quick look at the cancer paper which, with all the other reports is available for free download in this edition of the Annals of Nutrition & Metabolism. Most of the stuff in this summary is C&P but I added a few points. Keep an eye out on the web for more summaries.

The reviewer looked at five cancer types associated with fat intake: colorectal, ovarian, breast, endometrial and prostate cancers.

There is a possible relationship between high saturated fat intake and a modest increase in breast cancer (BC) risk. Monounsaturated fats from meats are linked to increased BC risk, but from olive oils they decrease the risk; possibly because of different effects from vegetable and animal fats on the blood sugar insulin or the way in which olive oil affects our enzymes. In animal models, some fats reduce BC risk if consumed as vegetable oil but the same fat will increase the risk if in processed food. Fish doesn’t seem to reduce risk in Western women, perhaps because of pollutants or overall crap diet compared to Asian and Mediterranean women, where fish consumption is associated with a decreased risk.

Total fat very likely contributes to increasing endometrial cancer (EC) risk through constitution of body fatness, and animal fat in particular appears to be responsible for this risk increase. The risk of ovarian cancer also appears to be reduced by reducing animal fat by increasing vegetable fat intake; but the data for EC and OC are too few to come to a conclusion. Total fat intake between 30 and 33% of total energy intake is not associated with increased risk of BC, EC and OC.

Due to the difficulty in extricating the relationship between total fat consumption and total energy consumption, fat cannot be considered as a risk factor for colorectal cancer (CRC). However a low-fat diet was associated with a decreased risk of CRC. fish intake probably decreases CRC risk, seemingly because of the presence of long chain omega 3 fatty acids DHA and EPA as well as other nutrients like selenium and vitamin D. It should however be noted that recent evidence not included in the WHO/FAO review indicates a mechanism for CRC by the effect on a class of proteins, finding that increased dietary intake of total fat, saturated fat, cholesterol, and red meat was significantly associated with CRC (Mrkonjic et al, 2009).

There is not a large body of evidence to indicate trans fats are responsible for these cancers, but men consuming trans fats may be increasing their risk of prostate cancer (PC). Several studies have reported that a high ratio of omega6:omega3 fatty acids is associated with an increased risk of CRC, BC and PC. Since there is no indication that increased intake of omega 6 acids causes cancer, it is probably the low intake of omega 3’s which is driving this relationship due to the reduced capacity to benefit from their protective effects.

Sources:
Mariette Gerber (2009).Background Review Paper on Total Fat, Fatty Acid Intake and Cancers. Ann Nutr Metab55:140–161

M Mrkonjic, E Chappell, VV Pethe, M Manno, D Daftary, CM Greenwood, S Gallinger,
BW Zanke, JA Knight and B Bapat (2009). Association of apolipoprotein E polymorphisms and dietary factors in colorectal cancer. British Journal of Cancer 100: 1966 – 1974

Misinformation is the headline

2009-08-20T10:17:00.002+10:00

I was astounded to see this article in my local paper today.

Popcorn a health food
August 20, 2009
US scientists have discovered that popcorn contains the same amount of healthy antioxidants as fruit and vegetables because it is a whole-grain food.

Researchers at the University of Scranton, Pennsylvania, found that whole-grain products had comparable antioxidants per gram to fruits and vegetables.

''Early researchers thought that the fibre was the active ingredient for benefits in whole grains, the reason why they may reduce the risk of cancer and coronary heart disease,'' said Joe Vinson, who led the study.

''But recently, polyphenols emerged as potentially more important. We were surprised by the levels of polyphenols we found in popcorn.''

http://www.theage.com.au/world/popcorn-a-health-food-20090819-eqjc.html

I sent the following letter to them. If they don't run it (or something similar, as I'm sure there will be plenty of scientists and health professionals who will leap on this) I'll then pass it on to a TV program called Media Watch which highlights intentional misinformation in the most embarrassing ways.

"I would implore The Age to review your policy over headline choice as this article is an example of misinformation. A single beneficial property in a food does not make it a “health food” when there are other elements which must be restricted. The high salt and fat in popcorn means that in no way is it a health food. Just because it contains high levels of a chemical with antioxidant properties doesn’t mean there are not still increased risks of the cancers and cardiovascular diseases which high salt and fat intakes are associated with. This junk food may be better in some ways than some other junk foods, but it should never be compared to fresh fruit and vegetables."

Update: Dairy for children 'extends life'

2009-08-10T06:53:00.001+10:00

So I got hold of the Bristol Uni/QIMH report from Heart. And there are some major problems here. Without boring you with a bunch of details on statistics, I’ll just point out that we use measures to estimate the variation in research and these often say more about the results than the results do. The authors of this study have ignored this, presenting information which has low statistical power as significant results in some cases and then drawing some pretty dodgy conclusions on the results. But they basically explain what is wrong with their conclusions in the text, which of course is not focused on by news media.

Just recapping quickly, the BBC article claimed that kids who ate the most dairy in childhood had the lowest risk of death from chronic heart disease (CHD) or stroke. But look what else the authors tell us about kids who ate the most dairy:

“Children in the highest group of dairy intake were more likely to be in a household with high food expenditure during childhood, more likely to have a father in a high occupational social class, and less likely to live in a deprived area or smoke as an adult than were those in the lowest intake group.”

“Children in the highest group of dairy intake were younger and their household’s intakes of vegetable and fat were higher compared to those in the lowest intake group. Dairy intake was highly correlated with total calcium intake. Intake of fruit, vegetable, egg and egg dishes, protein, fat, and energy intake was also highest in those with the highest baseline calcium intake.”

So basically they had the best all round nutrition. And since they were wealthier we can also assume they’ve had better welfare/health care and perhaps also better education which means they could be actively reducing their other risk factors such as smoking.

The authors then go on to explain that high dairy or calcium intake was associated with reduced risks of mortality from various different causes, even suicide. I can only assume that the only analyses they performed was related to dairy and dietary calcium, as they don’t report on whether the other correlations with high dairy and calcium intake (ie fruit, vegetable intake etc) also showed the same relationships or gave different results. If the agency that funded the research (World Cancer Research Fund, who was also involved in the American Institute for Cancer Research’s review of dietary cancer research) only were interested in the associations with dairy intake then this is a reasonable conclusion.

But what really stands out in this material is the fact that the data is obtained from what families ate for a single week in the 1930’s and was extrapolated out for their entire lives. More importantly, the data didn’t provide specific information on who ate what, so they made assumptions that of the foods consumed in a single household, the number of children in that household ate a given proportion and they further assumed that it was children consuming the most dairy. The authors note this, but then go on to make more assumptions on their already weak data:

“Data from the 1997 follow-up study in a sub-group of the study participants showed that the correlation between milk intake in childhood and that in adulthood was very low and thus these results are unlikely explained by similar dairy and calcium consumption patterns in adulthood and probably point to a childhood-specific effect.”

What? Probably a childhood specific effect? Or could it be that there was some other factor in the first place like overall nutrition that drives this relationship?

In closing, they point out another weak point in their material.

“The macro-environment of participants has varied considerably between the time of participation in the study at baseline, as children in 1930-ies pre-war Britain, and the time of their death. Conditions during the second World War, and participants’ environment as adults in the second half of the twentieth century will have been considerably different from those in the 1930ies. Food availability, general income, and health and housing standards have varied considerably during the study period, but such changes could not be considered in the analyses.”

To say nothing of the incredible differences in dairy and other food production systems occurring between now and then. That is what really bugs me about this study and the articles which sprang up all over the web suggesting that feeding kids dairy will help them live longer. The dairy products these people ate are not like dairy products today, thanks to the technology associated with intensive milk production. But since there are obvious holes in this report which require further explanation, I would go as far as saying this report is misleading.

So there you have it. This research teaches us nothing about nutrition, but it does reiterate the need for good data and thorough analysis. As George Fuechsel said, “Garbage in, garbage out”. Pity the BBC didn’t approach this material from the same perspective when they suggest that it backs the practice of giving dairy to children beyond infancy.

References:
Jolieke van der Pols, David Gunnell, Gail Williams, Jeff Holly, Chris Bain and Richard Martin (2009). Childhood dairy and calcium intake and cardiovascular mortality in adulthood: 65-y follow-up of the Boyd Orr cohort. Heart published online 29 Jul 2009 doi:10.1136/hrt.2009.168716.

This is going to be fun...

2009-07-29T08:33:00.003+10:00

It seems that in honour of the anniversary of the moon landing, researchers from the University of Bristol and the Queensland Institute of Health have made a gigantic leap of their own with the conclusion that people followed in an observational study undertaken in the 1930's have lower risks of stroke due to the amount of dairy consumed back then as children.

I can't get access to the report described in the following article from the BBC health website until it is published next month. As soon as it is out I'll give an update to this post. But I just couldn't wait to mention this, as I'm almost certain its will be loaded with overlooked variables. Perhaps I'll have to eat my words, and I'll happily do so if that is the case. I'd still rather do that than eat dairy!

Dairy for children 'extends life'

Children who eat plenty of dairy foods such as milk and cheese can expect to live longer, a study suggests.

Some 4,374 UK children from a 1930s study were traced 65 years later by researchers in Bristol and Queensland.

They found those who had had high dairy and calcium intakes as children had been protected against stroke and other causes of death, journal Heart reports.

Despite dairy containing artery furring fat and cholesterol, high consumption did not raise the heart disease risk.

The findings appear to back the practice of giving extra milk to schoolchildren.

click here for full article

Warning labels on hotdogs

2009-07-26T19:16:00.002+10:00

Last week a lawsuit was placed against several major processed food corporations in the US, due to their failure to include warning labels on products which increase the risk of dietary cancers. The suit appears to have been placed on behalf of The Cancer Project, an offshoot of Dr Neil Barnard's Physician's Committee for Responsible Medicine (PCRM). Many vegans will be familiar with the PCRM as they fund and produce scientific research into vegan diets and the risks associated with consuming meat and dairy products. I cannot take their research seriously as a result, not because they will never publish any findings which indicate that meat or dairy is not harmful; but because I automatically disregard anything produced by meat industry lobby groups such as Meat and Livestock Australia which will never publish material that indicates their products are harmful. Instead I always look for independent research and try and ensure there are no biases or conflicts of interest involved.

But this is not the issue I have today. I want to point out this report from the LA Times which described the lawsuit. Journalist Jerry Hirsch states that the lawsuit cited the American Institute for Cancer Research's recommendation that people "avoid processed meats", and counters this by citing a Harvard review which found no relationship between cancer and processed meats. The difference here is that while the Harvard review looked at 14 different investigations into diet and cancer, the AICR spent 5 years looking at over 7000 studies before they recommended that consumption of red meats should be limited to two serves per week and processed meats should be avoided.

While acknowledging the associations between processed meats and cancer, the AICR has distanced itself from the lawsuit with this press release.

References:

World Cancer Research Fund / American Institute for Cancer Research.

Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective.

Washington, DC: AICR, 2007

Click here to read the executive summary.

Vegetarians and cancer risk

2009-07-26T05:10:00.001+10:00

A few weeks ago I wrote a letter which will be published in the next Vegan Voice magazine (out in September) commenting on this article on the BBC health website. The article describes how a report in the British Journal of Cancer called "Cancer incidence in British vegetarians" indicates that like meat eaters, vegetarians are at risk of developing bowel cancer¹; contradicting an abundance of earlier information. This is why I decided to start this blog, although since doing so I have found another one from a vegan dietician which already looked at this report and is produced by someone who is more qualified than me. In any case, I will continue to publish my thoughts on relevant material but please keep an eye on Dina's blog Vegan RD as it looks like she really knows her stuff.

The data for the Key et. al BJC report was obtained from two studies, the Oxford vegetarian study and the more recent EPIC-Oxford study. These two studies used different methods of obtaining information from the subjects. The Oxford study used a simple questionnaire, while the EPIC-oxford study followed up a questionnaire with a food diary which provides more accurate details of variations in the diet, and allows differences in a dietary cohort to be quantified. For example, a person categorized as a "meat eater" answers how many times per week they eat meat in the questionnaire, but all this indicates for a vegetarian is that they don't eat meat. A food diary indicates how often a vegetarian ate processed foods, which is crucial for a dietary cancer study since fat intake is linked to cancer.

In fact, in the previous issue of the BJC another report described how fats were linked to bowel cancer due to their effects on a particular class of proteins². Basically this could not be assessed in the vegetarians among the Oxford study as the wrong questions were asked, which means that the findings of increased bowel cancer risk in vegetarians is imprudent as they were unable to compare the rates of cancer among vegetarians who consumed relatively little dietary fat with those who ate lots of it. In fact, the relevant variations which may have been indicated by the EPIC-Oxford cohort were disregarded.

Other issues in the study relate to the lower risk of cancers of the stomach, bladder and blood in vegetarians. There is evidence indicating fat intake is linked to the increased risk of bladder cancers³, but it may be that the impacts of fat intake on bladder cancer in vegetarians are offset by some other dietary component. It has been shown that people with high levels of vegetable fat in the diet have reduced risk of developing gastric cancers⁴. So while a vego diet which is high in fat may be protecting against stomach cancer, it may also be increasing your risk of colon cancer. You can see why it is important to disentangle these relationships when we are talking about something as serious as cancer.

People with a family history of bowel cancer must be more careful than the rest of us about what they eat because they may have a genetic predisposition for the development of colorectal cancers, so they may read the BBC article and conclude that they are at no less risk sticking to a vego diet than eating meat; which simply isn't true. It is fats (in particular saturated fats) which must be avoided; and vegetables provide necessary fibre which is essential in colon health. Also the type of iron in meat (heme iron) is indicated to be a major factor in the development of colorectal cancers as it affects the lining of the colon. The best way to reduce your risk of colorectal cancer is to adhere to a vegetarian diet, and focus on fresh fruits and vegetables with only moderate intake of processed foods.

References

1: Cancer incidence in British vegetarians

TJ Key, PN Appleby, EA Spencer, RC Travis, NE Allen, M Thorogood and JI Mann

British Journal of Cancer (2009) 101, 192 – 197

2: Association of apolipoprotein E polymorphisms and dietary factors in colorectal cancer

M Mrkonjic, E Chappell, VV Pethe, M Manno, D Daftary, CM Greenwood, S Gallinger, BW Zanke, JA Knight and B Bapat.

British Journal of Cancer (2009) 100, 1966 – 1974

3: Nutritional Factors and Gastric Cancer in Spain

CA Gonzalez, E Riboli, J Badosa, E Batiste, T Cardona, S Pita, JM Sanz, M Torrent and A Agudo

American Journal of Epidemiology (1994) 139, 466-473

4: Dietary patterns, nutrient intake and gastric cancer in a high-risk area of Italy

D Palli, A Russo and A Decarli

Cancer Causes and Control (2001) 12, 163-172

welcome to veg health news

2009-07-23T19:36:00.004+10:00

Do you follow the news? Are you frequently seeing information which says that eating one thing is bad, and another is good, when it contradicts what you've seen in other reports?

The reason this happens is because journalists are not required to publish material which is based on quality science, rather they publish material that is deemed newsworthy. This means some articles are describing studies which are utter rubbish.

So with this blog, I will strive to keep you up to date on what is appearing in the news, and give my opinion as a biologist on whether the info should be taken seriously, or needs to be considered in light of other information.