Monday, December 10, 2007

The vitamin D scare again

They already put the stuff in butter and margarine. If there really is a problem let them put a bit more in

MILLIONS of Australians are living with dangerously low levels of vitamin D, putting them at risk of developing fractures, bone disease and deadly illnesses. A quarter of a century after the Slip, Slop, Slap skin-cancer campaign was launched, several prominent endocrinologists, orthopedic specialists and other experts say the message to cover up has led to vitamin D deficiencies in between 30% and 70% of the population.

While no one disputes the potentially fatal consequences of too much sun exposure, health experts say some safe time in the sun each day is essential for maintaining healthy levels of vitamin D, a crucial bone-strengthening nutrient produced when skin is exposed to sunlight. Endocrinologist Professor Peter Ebeling, head of Osteoporosis Australia, has linked the low levels of vitamin D to a massive increase in the number of people being treated in hospitals with osteoporosis-related broken bones — up from a daily average of 177 to 262 — in the past six years. It costs the health system $1.9 billion a year to treat them.

Professor Ebeling said a study earlier this year showed more than three-quarters of general patients presenting at the Royal Melbourne Hospital had lower than recommended levels. "It's very serious," he said. "A lot of us have been worried about if for a long time but have just realised how widespread it is over the last five to 10 years."

Recent research in Geelong, south-east Queensland and Tasmania found about 40% of residents had insufficient vitamin D levels. During winter, the number of women in Geelong with low levels rose to 54%. Emerging evidence has also linked deficiencies in vitamin D to colon, breast and prostate cancer, diabetes, multiple sclerosis and other diseases. [Note that this article found that vitamin D had NO overall effect on cancer deaths. See also here]


Studies show how fruit, veges reduce cancer

The research results described below do not yet appear to have made it into journal publication so cannot be critically evaluated as yet. The results among humans were probably all just a social class effect, however. Middle class people are healthier and also more likely to report that they eat raw broccoli (whether they do or not). Amusing that you have to eat your vegetables raw, though

JUST three servings a month of raw broccoli or cabbage can reduce the risk of bladder cancer by as much as 40 per cent, researchers report. Other studies show that dark-colored berries can reduce the risk of cancer too - adding more evidence to a growing body of research that shows fruits and vegetables, especially richly coloured varieties, can reduce the risk of cancer.

Researchers at the Roswell Park Cancer Institute in Buffalo, New York, surveyed 275 people who had bladder cancer and 825 people without cancer. They asked especially about cruciferous vegetables such as broccoli and cabbage. These foods are rich in compounds called isothiocyanates, which are known to lower cancer risk.

The effects were most striking in non-smokers, the researchers told a meeting this week of the American Association of Cancer Research in Philadelphia. Compared to smokers who ate fewer than three servings of raw cruciferous vegetables, non-smokers who ate at least three servings a month were almost 73 per cent less likely to be in the bladder cancer group, they found.

Among both smokers and non-smokers, those who ate this minimal amount of raw veggies had a 40 per cent lower risk. But the team did not find the same effect for cooked vegetables. "Cooking can reduce 60 to 90 per cent of ITCs, (isothiocyanates)," Dr Li Tang, who led the study, said.

A second team of researchers from Roswell Park tested broccoli sprouts in rats. They used rats engineered to develop bladder cancer and fed some of them a freeze-dried extract of broccoli sprouts. The more they ate, the less likely they were to develop bladder cancer, said Dr Yuesheng Zhang, who led the research. They found the compounds were processed and excreted within 12 hours of feeding. That suggests the idea that compounds are protecting the bladder from the inside, Dr Zhang said. "The bladder is like a storage bag, and cancers in the bladder occur almost entirely along the inner surface, the epithelium, that faces the urine, presumably because this tissue is assaulted all the time by noxious materials in the urine," Dr Zhang said.

In a third study, a team at The Ohio State University fed black raspberries to patients with Barrett's esophagus, a condition that can lead to esophageal cancer. Black raspberries, sometimes called blackberries or blackcaps, are also rich in cancer-fighting compounds. Ohio State's Laura Kresty and colleagues fed 32 grams of freeze-dried black raspberries to women with Barrett's esophagus and 45 grams to men every day for six months.

They measured urine levels of levels of two compounds - 8-isoprostane and GSTpi - that indicate whether cancer-causing processes are going on in the body. Kresty said 58 per cent of patients had marked declines of 8-isoprostane levels, suggesting less damage, and 37 per cent had higher levels of GSTpi, which can help interfere with cancer causing damage and which is usually low in patients with Barrett's.



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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