Saturday, January 13, 2007


It's a well-known paradox that had little evidence to support it, until now. Doctors from UCLA's David Geffen School of Medicine have, for the first time, successfully demonstrated that obese patients actually fare better and have better chances of survival when hospitalised for acute heart failure than their leaner counterparts.

In the first-ever large scale study to assess the relationship between Body Mass Index and survival in patients hospitalised with acute heart failure, doctors have found the obesity paradox - BMI being inversely associated with long-term mortality in chronic heart failure - to be real. The study has found that by weight category, in-hospital mortality rate was 6.3% for underweight, 4.6% for healthy weight, 3.4% for overweight and 2.4% for obese patients. Researchers also found that for every five-unit increase in body mass, the odds of risk-adjusted mortality fell 10%, irrespective of the patients age, sex, blood urea nitrogen, blood pressure and additional prognostic factors.

Speaking to TOI, Gregg Fonarow, the school's director and lead author of this study, said, "The study suggests overweight, obese patients may have a greater metabolic reserve to call upon during an acute heart failure, which may lessen in-hospital mortality risk. Prior studies in outpatients with chronic heart failure had shown overweight patients had better chances of survival compared to patients who were normal weight, the so called obesity paradox."

Fonarow said the study was initiated in October 2001 and involved 263 hospitals in the US. Researchers utilised data of over 100,000 patients with acute heart failure patients from the Acute Decompensated Heart Failure National Registry from October 2001 through December 2004. "Further study is required but the finding suggests that nutritional/metabolic support may have therapeutic benefit in specific patients hospitalised with heart failure. Obesity is a known risk factor for developing heart disease and heart failure and every effort should be made to avoid it, but once heart failure has manifested, this paradox seems to occur," Fonarow added.

According to cardiologist Dr K K Agarwal of Moolchand Hospital, obesity paradox is also called reverse epidemiology. "Such a paradox has been found in obese patients undergoing dialysis or suffering from advanced cancer and renal failure. Elderly patients who have better BMI have better chance of pulling through such severe health complications."



Panic: `Health warning over safety of bottled water', says the UK Independent, among others, following a report by the food and farming campaign Sustain. The report argues that consumers often buy bottled water because they believe it is healthier than tap water. However, the bottled variety can contain sodium, contaminants (like the benzene found in Perrier in 1989), and the heavy metal antimony. The report notes that the French Senate has recommended switching brands regularly to reduce the risk of harmful effects.

Don't panic: The real aim of the report seems to be to emphasise that bottled water is less environmentally efficient than tap water - so why create a health panic about the bottled stuff?

The authors make a perfectly reasonable defence of tap water. They rightly point out that there are no particular health benefits from bottled water, and nor do we need to drink `eight glasses per day' as is routinely cited. Tap water is now produced to very high standards - 99.96 per cent of UK mains supply now meets national standards. Tap water is generally purer and fresher than the bottled variety, and also much cheaper.

However, some of the other claims in the report are dubious. The risks of sodium in the diet are overhyped anyway, but there is at least 25 times more sodium in a single slice of bread than to be found in a regular 500ml bottle of water. To reach the recommended sodium intake for a day from water would require drinking about 200 such bottles.

As for the claim about antimony, the report cites research from Germany which actually states `all the water tested contained antimony below the guidelines recommended for drinking water'. In other words, as far as anyone can tell, it is safe. While dismissing health fears about tap water, the report prefers to stoke fears about bottled water using innuendo rather than evidence.

Bottled water is convenient and usually preferable to the saccharin-sweet fizzy drinks that are the only alternative when you need to quench your thirst while out and about - even if it is sometimes ridiculously expensive. Claiming that it is potentially bad for your health is cynical, however. If Sustain think the world would be a better place if we only drank tap water, or at least recycled the plastic mineral water bottles, then they should make the case without promoting a different set of anxieties instead.



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].

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.

The use of extreme quintiles (fifths) to examine effects is in fact so common as to be almost universal but suggests to the experienced observer that the differences between the mean scores of the experimental and control groups were not statistically significant -- thus making the article concerned little more than an exercise in deception


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