Thursday, November 02, 2006


Journal abstract below:

Food groups and renal cell carcinoma: A case-control study from Italy

By Francesca Bravi et al.

Although nutrition and diet have been related to renal cell carcinoma (RCC), the role of specific foods or nutrients on this cancer is still controversial. We evaluated the relation between a wide range of foods and the risk of RCC in an Italian case-control study including 767 patients (494 men and 273 women) younger than 79 years with incident, histologically confirmed RCC, and 1,534 controls (988 men and 546 women) admitted to the same hospitals as cases for a wide spectrum of acute, non-neoplastic conditions, not related to long term diet modifications. A validated and reproducible food frequency questionnaire, including 78 foods and beverages, plus a separate section on alcohol drinking, was used to assess patients' dietary habits 2 years before diagnosis or hospital admission. Multivariate odds ratios (OR) were obtained after allowance for energy intake and other major confounding factors. A significant direct trend in risk was found for bread (OR = 1.94 for the highest versus the lowest intake quintile), and a modest excess of risk was observed for pasta and rice (OR = 1.29), and milk and yoghurt (OR = 1.27). Poultry (OR = 0.74), processed meat (OR = 0.64) and vegetables (OR = 0.65) were inversely associated with RCC risk. No relation was found for coffee and tea, soups, eggs, red meat, fish, cheese, pulses, potatoes, fruits, desserts and sugars. The results of this study provide further indications on dietary correlates of RCC, and in particular indicate that a diet rich in refined cereals and poor in vegetables may have an unfavorable role on RCC.

(From International Journal of Cancer, 2006)

There appears to have been no control for socioeconimic status so at a quick guess I suspect that the authors have simply shown once again that the poor have poorer health. I don't know a lot about Italian dietary habits but I suspect that the poor eat more bread and the rich eat more meat. The journal must be very careless of its reputation to publish such rubbish.

Statistical note: The use of odds ratios and reliance on extreme quintiles can obscure that fact that the differences in the means were very small and may obscure not-uncommon curvilinear relationships. I would hazard a guess that if the relationship had been expressed as a biserial correlation between bread consumption and patient group the relationship would have been shown as very weak indeed. And weak relationships tend to be poorly replicable

Root cause of cot death found?

Genetics again!

Scientists believe that they have found the underlying cause of cot death, a condition that claims the lives of hundreds of babies every year. Research into dozens of fatalities identified as the result of sudden infant death syndrome showed that the victims had a brain abnormality that prevents the detection of insufficient oxygen levels in the body. As a result, babies with the condition can be smothered in their bedclothes, especially if sleeping on their fronts. The researchers said yesterday that this was the strongest evidence yet of a common cause for cot death, and that it opened up the possibility of detecting those at risk and treating them.

Three hundred babies died of cot death in Britain last year, a 16 per cent fall compared with 2004. The decrease is credited to greater alertness among parents and better ways of determining causes of death, resulting in fewer cases classified as cot death.

The US team, led by David Paterson, of Boston Children's Hospital, examined postmortem samples from the brainstems of thirty-one babies who had suffered a cot death, comparing them with ten babies who had died of other causes. They were following up research suggesting that cot-death babies had an innate difference in the brainstem, the part of the brain responsible for controlling breathing, heart rate, blood pressure, temperature and arousal.

Three studies had found that cot-death babies had a reduced ability to use and recycle serotonin, a chemical best known for regulating mood but which has other roles. Scientists said the new study, published in the Journal of the American Medical Association, offered the most convincing confirmation yet of the link.

The babies examined had twice as many brain cells that either manufacture or use serotonin as did those of the babies who died of other causes. But the cells that use serotonin also had significantly fewer binding sites - places on the outside of the cells where serotonin "docks" and acts as a signalling chemical.

Dr Paterson said that the group's hypothesis was that they were observing a "compensation mechanism". He said: "If you have more serotonic neurons, it may be because you have less serotonin and more neurons are recruited . . . to correct this deficiency." Strikingly, boys who had died of cot death had significantly fewer serotonin receptors than girls, a finding that would be consistent with the fact that cot deaths are more common among boys.

Hannah Kinney, the paper's senior author, said: "These findings provide evidence that sudden infant death syndrome is not a mystery but a disorder that we can investigate and some day may be able to identify and treat." The study suggests that the slight abnormalities in the brainstem may impair a baby's ability to sense high carbon dioxide and low oxygen levels. This would increases the risk that a baby will inhale its own exhaled breath and become deprived of oxygen. "A normal baby will wake up, turn over, and start breathing faster when carbon dioxide levels rise," Dr Kinney said. But in babies who die from sudden infant death syndrome, defects in the serotonin system may impair these reflexes.

Such circumstances are far more likely to arise if a baby is placed face down in the cot. Campaigns to put babies on their backs have had great success, halving the numbers of cot deaths in the past decade.

The Foundation for the Study of Infant Deaths called the findings important and said that they were unlikely to be due to chance or sampling error. The Scottish Cot Death Trust, which part-funded the new research, said: "It looks like a really interesting piece of work and we welcome it as a way of starting to sift out the many possible factors in cot death."

Marian Willinger, of the US National Institute of Child Health and Human Development, which funded the study, said that putting babies to sleep on their backs was important but as yet doctors could not target high-risk infants because of problems identifying them. Dr Willinger said that the research improved the understanding of the process that underlay cot death, and the chances of helping at-risk infants. However, George Haycock, scientific adviser to the Foundation for the Study of Infant Deaths, added that a brain abnormality was unlikely to be the sole cause."Much more research is needed to understand and, ultimately, to prevent these tragedies," he said.



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? It is just about pure fat. Surely it should be treated as contraband in kids' lunchboxes! [/sarcasm].

9). For a summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and no lasting harm from them has ever been shown.


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