Thursday, October 04, 2007

Dangerous excess of exercise

More casualties of the obesity war

Nearly one-quarter of gym-goers exercise at levels that can be dangerous to their health, new research shows. A study of more than 200 gym users at the Brunswick City Baths, in Melbourne, revealed that 23 per cent of people exercised between six and 20 hours a week and had become dependent on their physical fix. This group, defined as excessive exercisers, did more vigorous levels of exercise for longer periods than their non-excessive counterparts, according to the study, presented in Brisbane last week at the Australian Psychological Society's annual conference.

Jane Fletcher, a psychologist and co-author of the study, said people who exercised excessively often did so when they were sick or injured. "Exercise is not bad in itself. It is whether it interferes with your work, social life and family life that may indicate whether you have a problem," she said. Some of the worst cases were of people being sick off work and still going to the gym or those insisting on exercise in 40-degree heat, Dr Fletcher said. "It's more than just the number of hours they exercise each week. It's about … the reasons behind why they might be exercising." Overdoing it can lead to repetitive-use injuries and chronic infections due to lowered immunity - and women can experience stopped periods and osteoporosis.

The executive director of the Eating Disorders Foundation of NSW, Amanda Jordan, said addiction to exercise was often the first sign of an eating disorder. She said anti-obesity messages encouraging exercise and healthy living could be misconstrued by those already vulnerable to eating disorders. "It can begin as something which is quite moderate and contributing to fitness and then you start getting into real strife because people do not know when to stop."

Jo Kildea, 24, of Kensington, understands the obsession with keeping fit. When she was 17, she began working out at the gym and going for walks "to get healthy and lose a bit of weight". Soon she was doing squats in the shower, star jumps and sit-ups in her room and running up and down the stairs of her house when nobody was home. Ms Kildea also began reducing her food intake and rapidly lost weight. She was treated for anorexia and now has a healthy exercise regime that includes walking and boxercise.



Long touted as the "safe" alternative to aspirin, there are signs that paracetamol is anything but. The study below is not very persuasive, though, as it is a classic "give huge doses to rats" study. There is however independent evidence that paracetamol causes liver damage. See also here

Reaching for the paracetamol alongside your morning coffee may be bad for your health, researchers say. A study indicated that a combination of large quantities of the pain-killer and caffeine appeared to increase the risk of liver damage. Scientists found that caffeine tripled the amount of a toxic by-product created when paracetamol was broken down. However, the University of Washington team so far has plied only bacteria and rats with large doses. British scientists emphasised that far more research would be needed to prove any danger to humans.

US researchers, writing in the journal Chemical Research in Toxicology, recommend that people should limit the amount of coffee or energy drinks they consume while taking paracetamol. Even relatively small overdoses of paracetamol can cause permanent damage to the liver. Scientists already know that heavy alcohol consumption can make the drug even more toxic, but this is the first suggestion that combining paracetamol and caffeine could produce a similar effect. Caffeine is added to many commercially available paracetamol tablets as it is believed that this increases their effects.

Sidney Nelson, who led the study, said: "You don't have to stop taking acetaminophen [paracetamol] or stop taking caffeine products, but you do need to monitor your intake more carefully when taking them together, especially if you drink alcohol." The study used E. coli bacteria that had been modified genetically to produce a key liver chemical which, in humans, helps the body to break down paracetamol.

When the bacteria were exposed to very large doses of paracetamol and caffeine together, the amount of the toxic by-product produced was tripled. This is the toxin that causes liver damage after a paracetamol overdose.

Dr Nelson said that the quantities of caffeine and paracetamol used in the study were far higher than most people would consume daily but added that the amount needed to produce a harmful effect in humans had not been calculated. Previous studies showing that high doses of caffeine can increase the severity of liver damage in rats with paracetamol-induced liver damage support this finding.

Some people are thought to be more vulnerable than others. These include those taking antiepileptic medication or St John's wort, which have been shown to boost levels of the enzyme involved. People who drink a lot of alcohol are also at higher risk because it can trigger another enzyme that produces the liver toxin.



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].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.


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