Wednesday, December 05, 2007


Smokers, barbecuers and coffee-drinkers watch out! They are after you! Yet another stupid epidemiological study based on self-reports and no way of excluding confounding factors -- such as obesity and poverty. The middle class are healthier and also much less likely to report consumption of unprestigious fast food and that alone could account for the small differences observed. See here for the much stronger evidence that acrylamide is NOT harmful.

I might also remark in passing that the differences found below were in rare cancers, were found in very old ladies and were found only between extremes of supposed acrylamide consumption. The use of extreme quintiles for analysis also tends to suggest that there was NO overall correlation between consumption and cancer. Throwing away three fifths of your data is not a persuasive analysis. Attention-seeking medical researchers often do it, though. Popular summary and journal abstract follow:

Fresh fears have been raised over the safety of cooked foods as a wide-ranging study found for the first time that a common chemical caused by frying, roasting or grilling can double the risk of cancer in women. Five years ago, scientists sparked a worldwide alert when they disclosed that many household foods contain the substance acrylamide, which was thought to be a probable cause of the disease. Now a study involving 120,000 people - half of whom were women - has established a direct link between consumption of the chemical and the incidence of ovarian and womb cancer.

Research has shown that acrylamide is found in cooked foods such as bread, breakfast cereals, coffee and also meat and potatoes which had been fried, baked, roasted, grilled or barbecued. The Dutch study found that women who absorbed more acrylamide were twice as likely to develop ovarian or womb cancer as those who ingested a smaller amount. The higher amount eaten by the women involved was the equivalent to a single packet of crisps, half a pack of biscuits, or a portion of chips a day.

The EU has now advised people to avoid burnt toast or golden brown chips because they contain higher levels of the substance acrylamide. They have also recommended eating home-cooked meals which contain much lower amounts of the chemical than processed products, fast food and restaurant meals.

The Food Standards Agency welcomed the report and called on consumers to heed the EU's advice. However, a spokesman said it was not possible to avoid the chemical entirely. "This new study supports our current advice and policy, which already assumes that acrylamide has the potential to be a human carcinogen," a spokesman said. "Since acrylamide forms naturally in a wide variety of cooked foods, it is not possible to have a healthy balanced diet that avoids it."

The findings from the University of Maastricht, published in the journal Cancer Epidemiology, Biomarkers and Prevention, came only a month after the public was warned about the increased risk of cancer from eating bacon and ham. It also came as the Government launches a five-year strategy to combat the disease.

The Dutch report relied on the Netherlands Cohort Study, which involved 120,000 people aged between 55 and 70, about 62,000 of them women. At the start of the study, participants completed a questionnaire that was used to estimate their acrylamide intake. The participants were followed up through the Dutch cancer registries and after 11 years, 327 had developed endometrial (womb) cancer, 300 were diagnosed with ovarian cancer and 1,835 suffered breast cancer. The study found that women who had eaten 40 micrograms of acrylamide a day (found, for example in a 32g pack of crisps) had double the risk of endometrial cancer and ovarian cancer than women in the lowest category. There was no link found to breast cancer.

Janneke Hogervorst, at the Department of Epidemiology at Maastricht University, said that "this is the first observation of an association between dietary acrylamide intake and cancer in humans". But she warned: "It is important that these results are corroborated and confirmed by other studies before far-reaching conclusions can be drawn."

About 6,400 women are diagnosed with womb cancer in Britain each year and 7,000 with ovarian cancer, one of the highest rates in Europe. The FSA said people should try to have less fried and overcooked food in their diet. "People should eat a balanced healthy diet which includes plenty of fruit and vegetables, bread, other cereals and potatoes," a spokesman said. "They should also limit the amount of sugary and fatty foods they eat, including fried food such as chips and crisps."

The EU called on people not to overcook their food. "General advice, resulting from this project, is to avoid overcooking when baking, frying or toasting carbohydrate-rich foods," it recommended. "French fries and roast potatoes should be cooked to a golden yellow rather than golden brown colour and bread should be toasted to the lightest colour acceptable."

Dr Lesley Walker, of Cancer Research UK, tried to calm fears over the link, suggesting that other factors could have a greater impact on the chances of cancer. "Women shouldn't be unduly worried by this news," she said. "It's not easy to separate out one component of the diet from all the others when studying the complex diets of ordinary people. "And as acrylamide levels are highest in carbohydrate containing foods - such as chips and crisps - other factors need to be firmly ruled out, especially being overweight or obese, which we know is strongly linked to womb cancer and probably linked to ovarian cancer."

A Food and Drink Federation spokesman said: "The food manufacturing industry has made huge efforts to reduce the formation of acrylamide in manufactured foods using a variety of techniques. "Considerable progress has already been made in reducing levels - for example potato crisps 30-40 per cent, potato fries 15 per cent, crispbread 75 per cent - but more work is needed on coffee."

When the alarm was raised in 2002, the FSA tested a number of products, including Walkers Crisps, Ryvita crackers, Kellogg's Rice Crispies and Pringles crisps. They found higher levels of the chemical occurring naturally in the food than international safety limits permitted in the packaging of the product. Although people fry less food at home, the popularity of fast food means increasing levels are being consumed. In 2000, charred meat and blackened toast were condemned because other chemicals formed on the burnt food were found to contribute to the risk of cancer.


A Prospective Study of Dietary Acrylamide Intake and the Risk of Endometrial, Ovarian, and Breast Cancer

By Janneke G. Hogervorst et al.

Background: Acrylamide, a probable human carcinogen, was detected in various heat-treated carbohydrate-rich foods in 2002. The few epidemiologic studies done thus far have not shown a relationship with cancer. Our aim was to investigate the association between acrylamide intake and endometrial, ovarian, and breast cancer risk.

Methods: The Netherlands Cohort Study on diet and cancer includes 62,573 women, aged 55-69 years. At baseline (1986), a random subcohort of 2,589 women was selected using a case cohort analysis approach for analysis. The acrylamide intake of subcohort members and cases was assessed with a food frequency questionnaire and was based on chemical analysis of all relevant Dutch foods. Subgroup analyses were done for never-smokers to eliminate the influence of smoking; an important source of acrylamide.

Results: After 11.3 years of follow-up, 327, 300, and 1,835 cases of endometrial, ovarian, and breast cancer, respectively, were documented. Compared with the lowest quintile of acrylamide intake (mean intake, 8.9 mg/day), multivariable-adjusted hazard rate ratios (HR) for endometrial, ovarian, and breast cancer in the highest quintile (mean intake, 40.2 mg/day) were 1.29 [95% confidence interval (95% CI), 0.81-2.07; Ptrend = 0.18], 1.78 (95% CI, 1.10-2.88; Ptrend = 0.02), and 0.93 (95% CI, 0.73-1.19; Ptrend = 0.79), respectively. For never-smokers, the corresponding HRs were 1.99 (95% CI, 1.12-3.52; Ptrend = 0.03), 2.22 (95% CI, 1.20-4.08; Ptrend = 0.01), and 1.10 (95% CI, 0.80-1.52; Ptrend = 0.55).

Conclusions: We observed increased risks of postmenopausal endometrial and ovarian cancer with increasing dietary acrylamide intake, particularly among never-smokers. Risk of breast cancer was not associated with acrylamide intake.

Cancer Epidemiol Biomarkers Prev 2007;16(11):2304-13

Honey is better than children's cough syrups for a silent night

It is true that most cough mixtures are pretty useless most of the time

Natural honey is a more effective remedy for children's coughs than over-the-counter medicines, researchers say. A dose of buckwheat honey before bedtime easily outperformed a cough suppressant in a US study. Honey did a better job of reducing the severity and frequency of night-time coughs. It also improved sleep quality for children and their parents.

Dextromethorphan (DM), the active ingredient in many cough mixtures sold in chemists and supermarkets, had no significant impact on symptoms. Honey has been used in medicine for centuries, not only to treat coughs and bronchitis but also to assist the healing of wounds. For coughs it is often mixed with lemon, ginger or brandy.

Ian Paul, who led the researchers from Penn State College of Medicine in Hershey, Pennsylvania, said: "We hope that medical professionals will consider the positive potential of honey as a treatment, given the lack of proven efficacy, expense, and potential for adverse effects associated with the use of DM." DM can cause severe involuntary muscle contractions and spasms, the researchers said. Cases of teenagers using the drug to get "high" were also common, they said.

Dr Paul's team observed 105 children and teenagers with respiratory tract infections. The study ran over two nights. On the first, none of the participants was given any treatment. On the second, they were divided into groups who received either honey, an artificial honey-flavoured DM medicine or no treatment, about half an hour before bedtime. Parents answered questions about their child's symptoms and sleep quality, as well as their own ability to sleep. They rated honey as significantly better for the relief of symptoms. The findings are reported today in the journal Archives of Pediatrics & Adolescent Medicine.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). And how odd it is that we never hear of the huge American study which showed that women who eat lots of veggies have an INCREASED risk of stomach cancer? So the official recommendation to eat five lots of veggies every day might just be creating lots of cancer for the future! It's as plausible (i.e. not very) as all the other dietary "wisdom" we read about fat etc.

10). And will "this generation of Western children be the first in history to lead shorter lives than their parents did"? This is another anti-fat scare that emanates from a much-cited editorial in a prominent medical journal that said so. Yet this editorial offered no statistical basis for its opinion -- an opinion that flies directly in the face of the available evidence.

Even statistical correlations far stronger than anything found in medical research may disappear if more data is used. A remarkable example from Sociology:
"The modern literature on hate crimes began with a remarkable 1933 book by Arthur Raper titled The Tragedy of Lynching. Raper assembled data on the number of lynchings each year in the South and on the price of an acre's yield of cotton. He calculated the correla-tion coefficient between the two series at -0.532. In other words, when the economy was doing well, the number of lynchings was lower.... In 2001, Donald Green, Laurence McFalls, and Jennifer Smith published a paper that demolished the alleged connection between economic condi-tions and lynchings in Raper's data. Raper had the misfortune of stopping his anal-ysis in 1929. After the Great Depression hit, the price of cotton plummeted and economic conditions deteriorated, yet lynchings continued to fall. The correlation disappeared altogether when more years of data were added."
So we must be sure to base our conclusions on ALL the data. But in medical research, data selectivity and the "overlooking" of discordant research findings is epidemic.


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