Sunday, September 24, 2006

A sobering truth

A call to put warnings on alcoholic drinks may be the first shot in a new public health battle

Not so many years ago, the attitude of many towards alcohol was that if you weren't actually straining metal cleaner into a cup through a cloth, or could refrain from reaching for the whisky bottle before about lunchtime, then you probably didn't have too much to worry about on the health front. Even perpetual drunkards came to be referred to from about the middle of the 19th century by the term "lush", which implies more exoticism than disease. Associations in the public's mind between all but extreme alcohol intake and ill-health have traditionally been weak, reflecting its importance in many social and even religious rituals.

Could this status be under threat? A call this week by the Salvation Army for tougher rules on alcohol suggests the intoxicant might be about to follow tobacco in being targeted as a public health enemy. This Christian charity released a research finding that 61 per cent of Australians did not know that alcohol increased the risk of various cancers, including cancer of the breast, larynx and even the liver - despite the well-known association between heavy drinking and liver cirrhosis. Although alcohol is listed as a group 1 carcinogen - the highest rank - by the Cancer Council of Australia for the development of cancers of the mouth, pharynx, larynx, oesophagus and liver, only 12 per cent of Australians surveyed were definite that a link did exist.

And the Salvos said it was "high time clear warning labels in large type" were placed on drink cans and bottles "to spell out the dangers". The charity's suggested wordings for warning labels include the following: "alcohol can increase the risk of getting cancer including breast cancer and liver cancer"; "alcohol is a drug, you can become dependent on it", and the bald "alcohol can cause brain damage". "What is of such concern is that people don't know the facts - and they need to," says the Salvation Army's Gerald Byrne. "The Cancer Council Australia recommends that to reduce the risk of cancer alcohol consumption should be limited or avoided. The World Cancer Research Fund says even low levels of alcohol increase the risk of colorectal and breast cancer. The Cancer Council NSW says alcohol is a known risk factor for cancer . . . What we say is, why aren't people being told?"

Other experts concede the public is mostly ignorant of the added cancer risk caused by alcohol, but some are slightly more cautious about jumping in with warning labels. The Cancer Council Australia's CEO Ian Olver says the council is all for getting the risk message across, but warnings are only one method: "We haven't done any work about whether the best way to deliver that information is via warnings on bottles, and we'd probably want to do that before we looked at a specific strategy. But it's a strategy that clearly works with other products like cigarettes." At least the message with cigarettes has been consistent: for the sake of your health, quit.

For alcohol, however, things aren't that simple. To borrow the line from the public awareness campaign, every cigarette, even one, is doing you damage, but the picture for alcohol is muddied by the fact that at low levels any increased risk of cancer has to be offset against a probable health benefit in the form of lowered mortality from cardiovascular disease.

What this means, unfortunately, is that some of the messages being fed to the public about alcohol are contradictory. Australia's peak source of medical information and health guidelines, the National Health and Medical Research Council, issues official alcohol guidelines that set a general recommended limit of four standard drinks per day for men, and two for women (lower limits apply in some cases, for example pregnant women, pilots and people operating heavy machinery).

This is not a great deal of alcohol. As just 100ml of wine is about one standard drink, one glass of the size many people pour themselves for dinner or on arriving home from work can easily be twice this amount. But another set of guidelines put out by a separate NHMRC committee - the Dietary Guidelines for Australian Adults - say even this four and two-drink limit is too much, and recommend people drink half those amounts: just two standard drinks a day for men and one for women. (As a standard drink is defined as containing 10g of alcohol, the 100ml of typical-strength wine that that translates to equates to one middy of full-strength beer or a schooner of light beer.)

Olver defends the lower recommended alcohol intakes backed by the Cancer Council, saying they are appropriate because "the (cancer) risk starts with any alcohol consumption, and gets worse as you go on". According to figures on the Cancer Council NSW website, previous studies have established a link between alcohol and specific cancers, in some cases a strong link (see table). For cancers at all sites, the risk was unchanged for someone drinking less than 25g of alcohol a day, but increased by about 22 per cent if someone drank between 25g and 50g. For anyone drinking over 100g a day - 10 standard drinks - the cancer risk was nearly doubled. "We've got an overall figure (for how much alcohol increases cancer risk)," Olver says. "The Australian Institute of Health and Welfare put out a figure that in terms of the incidence of cancer, alcohol was a risk factor in 3.6 per cent of all cancers. They are 2001 figures." As there are about 88,000 cancers diagnosed a year, that means that in 2001 there were thought to be about 3168 people diagnosed with a cancer probably caused, or partially caused, by excessive alcohol.

"This needs to be put into proportion," Olver adds. "In that same (AIHW) document, smoking was a factor in 21.6 per cent of cancers. We don't want to get the message out of whack - alcohol's a risk factor, but it's nothing like the risk factor of cigarettes." Olver is cautiously supportive of warning labels on drinks, but only in the wider context that it's a good idea to get this health message out there. "I think it's important that all the risk factors are understood by the public - the public make lifestyle choices, just as they do with diet, and they can't make lifestyle choices if they don't know," he says. "We don't have a lot of evidence about which is the best way of doing it, but all we can say is that it's certainly worked in tobacco control. It's not an inappropriate method at all."

Stephen Leeder, professor of public health and community medicine at the University of Sydney and director of the Australian Health Policy Institute, says there is "no question that alcohol abuse represents a major public health problem. If you had to nominate major public health problems, if alcohol wasn't in someone's top three or four, you'd want to know what kind of book the person had been reading," he says. "It's a major problem." But Leeder says while the the "draconian" measures used to discourage tobacco use are not appropriate for alcohol - because unlike tobacco, moderate alcohol use is not associated with great harm - other measures may be. "There's a role for reminding people of the risks, if they can be expressed simply and clearly. I've no objection to that at all - people don't have to read them if they don't want to." Alcohol is thought to wreak its carcinogenic effects indirectly - either by interacting with tobacco, and increasing the damage tobacco's ingredients can wreak on tissues, or by making it easier for other cancer-causing compounds to pass through cell membranes.

Another alcohol expert, professor Paul Haber, says he thinks the NHMRC's Alcohol Guidelines - the ones that recommend up to four drinks a day for men and two for women - are the more relevant for Australians seeking overall health guidance. "It is clearly true that there are conflicting NHMRC-sponsored guidelines concerning alcohol use at present," says Haber, director of the Drug and Alcohol Service at Sydney's Royal Prince Alfred Hospital, who supports warning labels. "The key reason for this that I can identify is that differing health authorities consider issues from a sectarian approach: the cancer people think about alcohol and cancer, the nutritionists think about alcohol and nutrition, and the general people take an overall view. "Guidelines that focus on the risk of cancer alone will recommend that no one drinks. That is because alcohol does not protect against any form of cancer. "Alcohol promotes some cancers in a dose-dependent manner, and it not relevant to the causes of others. Therefore, the more you drink the higher the overall risk of cancer. With low levels of alcohol, the increased risk of cancer is tiny, and in many studies it may be so low that it cannot be discerned from zero risk."

Haber and the cancer gurus agree that excessive alcohol is harmful, that the risks include cancer, and the more you drink, the greater the risk. "The point of difference is whether a woman can drink one drink safely a day or two," Haber says. "Close to the border of safety, if there is an excess risk, it is very small and therefore difficult to measure confidently. Large studies, at high cost, are required to resolve these remaining doubts."


Calcium supplements useless

While calcium supplements have been touted to prevent broken bones in adults, providing them to children may not help prevent fractures as they age, Australian researchers report. "At two of the areas where we worry about fractures in later life ""the spine and the hip "" the giving of calcium supplements had no effect on bone health in children," said study lead author Dr. Tania Winzenberg, a musculoskeletal epidemiologist at the Menzies Research Institute, in Tasmania. "It had been thought that calcium supplements would be more helpful than that in children," she said. "So, giving calcium supplements to children has little effect on fractures, and fractures is what we worry about."

Her team's report is published in the Sept. 16 edition of the British Medical Journal. In their review, the researchers analyzed data collected from 19 different studies. The studies included nearly 2,900 children between three and 18 years of age, and focused on the benefits of calcium supplementation lasting at least three months. The studies tracked bone outcomes after at least six months of follow-up.

Winzenberg's team found only a small effect of supplementation on total-body bone mineral content and upper arm bone density. Children taking the supplements only had 1.7 percent better bone density in their upper arms compared to kids not taking the supplements. The team also found no effect on the rate of fractures seen later in life among people given calcium supplements as children. This was particularly true for common fracture sites, such as the hip and lumbar spine.

Based on the findings, Winzenberg's group recommends other approaches to improving kids' bone health, especially increasing vitamin D intake and eating more fruit and vegetables. Vitamin D is sourced mainly from exposure to sunlight, and is essential to the intestinal absorption of calcium.

The findings don't apply to children who may have significant problems with their bones or who can't eat dairy products, Winzenberg said. For healthy children, calcium remains an important part of the diet, she noted.

One expert agreed that calcium supplementation probably doesn't benefit healthy children. "Healthy children, with an adequate diet, may have all the calcium they need to build bone," said Dr. David L. Katz, an associate professor of public health and director of the Prevention Research Center at Yale University School of Medicine. "Growing bone might need a combination of materials, such as calcium combined with vitamin D, to grow stronger," he said. This study does not exclude a possible benefit of calcium supplementation for children with low intake of dietary calcium, or children with certain health problems, Katz said. "But it does indicate that calcium supplementation in healthy children is a questionable practice," he said. "For now, the tried-and-true approach to the early prevention of osteoporosis remains a healthful, balanced diet, and plenty of exercise," Katz 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.


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