Friday, February 15, 2008

Fast-food harms liver, but helps your heart

So if you are at risk from heart disease, eat at McDonalds! But sugar is bad for you! A rather silly study on the whole but fun nonetheless. What a study of force-feeding tells us, who could say? Note also that the preliminary report of this study reveals that the results were much more complex than described below

A month-long diet of fast food and no exercise led to dangerously high levels of enzymes linked to liver damage, in an unusual experiment inspired by the docu-movie "Supersize Me." But investigators, reporting their findings on Thursday, were also stunned to find that a relentless regimen of burgers, fries and soda also boosted so-called good cholesterol, seen as a key measure of cardiovascular health.

Researchers in Sweden asked 12 men and six women in their twenties, all slim and in good health, to eat two meals per day at McDonalds, Burger King or other fast-food restaurants over four weeks. The volunteers were also told to refrain from exercising. The goal was to increase body weight by 10 to 15 percent to measure the impact of an abrupt surge in calorie intake.

Blood samples were taken before, during and after the experiment to monitor levels of an enzyme called alanine aminotransferase, or ALT, a potential marker for liver damage often seen among heavy drinkers and patients with hepatitis C. Levels of ALT increased sharply after only one week, and quadrupled on average over the entire period, said lead researcher Frederik Nystrom, a doctor at the University Hospital of Linkoping. "The results scared me," he told AFP. "One of the subjects had to be withdrawn from the study because he had 10 times the normal ALT levels."

For 11 of the 18 subjects, ALT rose to levels that would normally reflect liver damage, even among individuals who did not drink any alcohol, although no such damage occurred, he said. Two of the individuals had liver steatosis, or fatty liver, in which fat cells build up dangerously in the liver, he said. Steatosis is associated with the risk of developing Type 2 diabetes, which has taken on epidemic proportions, especially in industrialised countries.

Published in the British Medical Association's journal Gut, the study "proves that high ALT levels can be caused by food alone," said Nystrom. That signs of liver damage were linked to carbohydrates was another key finding, he said. "It was not the fat in the hamburgers, it was rather the sugar in the coke," he said.

But the most startling result implies that an intensive fast food diet might have some health benefits too, apparently from fat. "We found that healthy HDL cholesterol actually increased over the four-week period -- this was very counter-intuitive," Nystrom said. HDL, sometimes called "good cholesterol," seems to clean the walls of blood vessels, removing excess "bad cholesterol" that can cause coronary artery disease and transporting it to the liver for processing.

Nystrom has yet to publish the cholesterol findings, but said they were consistent with the so-called "French Paradox." For nearly two decades, scientists have wrestled to explain how the French can consume a diet rich in fats -- from abundant butter, cream, cheese and meat -- yet have generally low levels of heart disease and hypertension. "The study showed that the increase in saturated fat correlated with the increase in healthy cholesterol," he said.

The young Swedish guinea pigs ate at least two fast-food meals a day, and terminated the study once they had gained a maximum of 15 percent in weight. On average, they tipped the scales 6.5 kilos (14.3 pounds) more, but one ballooned by 12 kilos (26.4 pounds).

Nystrom got the idea for his study from the 2004 Oscar-nominated documentary "Supersize Me," in which filmmaker Morgan Spurlock asked doctors to monitor him over a 30-day period in which he ate at McDonalds morning, noon and night. Doctors were so alarmed by changes in his blood chemistry -- including skyrocketing levels of ALT -- that they begged him to halt his experiment. "I wasn't just inspired by the movie, I copied it to the best of my ability," said Nystrom.

The movie helped spur a change of tack by fast-food corporations to include healthier options on their menus. On their websites, McDonald's and Burger King highlight salads and low-fat products -- alongside the classic burgers and colas -- and offer guidance on balanced diets and a healthy lifestyle.


Sitting down is now bad for you

But jogging is bad for you too because it crunches your joints. And swimming is bad because swimmers drown a lot. And walking outdoors is bad because you might get cancer from the sun. So just DIE!

SITTING down is about to join smoking and junk food on the list of vices that increase your risk of diabetes and heart disease. New Australian research shows that half-an-hour in the gym will not make up for the waist-expanding damage caused by spending the rest of the day sitting. But the good news is that pottering about the house or gently walking around the office while on the phone might be enough to keep you fit.

The study, which will appear in the April issue of Diabetes Care, joins the growing body of evidence suggesting too much sitting might undo the benefits of exercise. The study measured the intensity of physical activity in 168 subjects over seven days. It found that, regardless of how much moderate-to-vigorous exercise they did or their total sedentary time, those who took more breaks from sitting had lower waist circumferences, lower body mass indexes and lower levels of triglycerides and glucose in blood.

Higher levels of triglycerides, or blood lipids, have been linked to a heightened risk of heart disease and stroke. High blood glucose levels are linked to the development of diabetes, which itself is a major risk factor for heart disease. "What this shows is there are benefits in just getting up regularly and interrupting your sedentary time," principal researcher Genevieve Healy of the University of Queensland said.

Researchers behind the Stand Up Australia project have written to the Rudd Government requesting $3.5million for a two-year study into the impact of prolonged sitting on the health and productivity of workers. The study would also develop and test strategies for reducing sitting time on the job. The project is a a collaboration between the Baker Heart Research Institute and the International Diabetes Institute, which will merge this year, and the universities of Melbourne and Queensland.

The latest study builds on work that is shifting the health promotion focus from purposeful exercise, such as jogging or cycling, to lower intensity activity throughout the day.

The Australian research has been backed up by US studies, which show the sheer effort of standing up is enough to double the metabolic rate and the amount of calories burnt. "If you stand up, you are much more likely to end up pacing or pottering around and that seems to make a crucial difference," Professor Marc Hamilton from the University of Missouri told Britain's Daily Mail.

His studies found that the enzymes responsible for breaking down fat are suppressed when a person is sitting instead of standing. "To hold a body that weighs [77 kilograms] upright takes a fair amount of energy from muscles," he said. "There is a large amount of energy associated with standing every day that can't easily be compensated for by 30 to 60 minutes in the gym."

Studies by associate Professor David Dunstan, of the International Diabetes Institute, linked subjects who spent more time watching television with risk factors for diabetes and heart disease, regardless of their levels of moderate-to-vigorous exercise.



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 correlation 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 conditions and lynchings in Raper's data. Raper had the misfortune of stopping his analysis 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.

"What we should be doing is monitoring children from birth so we can detect any deviations from the norm at an early stage and action can be taken". Who said that? Joe Stalin? Adolf Hitler? Orwell's "Big Brother"? The Spanish Inquisition? Generalissimo Francisco Franco Bahamonde? None of those. It was Dr Colin Waine, chairman of Britain's National Obesity Forum. What a fine fellow!


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