Saturday, November 17, 2007

Why poor kids may make sicker adults

I had a little bet with myself when I saw this article that it would not mention genetics. I was right. The article essentially explains nothing. It just confirms that poor people are in general less healthy

Scientists have long known that the poor suffer worse health and shorter lives than the rich. Now, researchers have identified what they say are key mechanisms in 13-year-olds that may help explain why this occurs. The longer 13-year-olds have lived in poverty, the less efficient their bodies become in handling environmental demands, investigators found in a new study.

This "may be related to the fact that children who grow up in poverty have a steeper life trajectory of premature health problems than other children," regardless of later successes in life, said Gary Evans of the College of Human Ecology at Cornell University in New York. The study, coauthored by Evans and Cornell graduate student Pilyoung Kim, appears in the November issue of the research journal Psychological Science.

"Muted responses of stress regulatory mechanisms, which are part of the cardiovascular system, not only compromise the ability of the adolescents' bodies to respond to such stressors as noise, poor housing and family turmoil but also indicate they are suffering from more stress-induced physiological strain," said Evans. "It's very costly to society that low-income children end up getting sick prematurely and die younger."

Evans and Kim assessed markers of stress regulatory systems by measuring overnight levels of a stress hormone, cortisol, and blood pressure reactivity and recovery after a stressor -- being asked unexpectedly to do mental math problems. The assessments were conducted in 217 low and middle-income white adolescents at age 9 and again at 13 in rural New York.

The researchers assessed cumulative physical and social risk exposure by measuring crowding, noise and housing quality along with maternal and youth reports of family turmoil, separation from family and exposure to violence. "The study provides yet another piece of evidence that poverty and other chronic risk factors induce physiological changes that appear to be related to longterm health problems," said Evans. He also summarized his findings and made policy recommendations before the planning committee of the Robert W. Johnson Foundation Commission to Build a Healthier America on Oct. 17 at the Brookings Institution in Washington, D.C.


Alzheimer's "vaccine" seen to help mice

It's a long way from specially-bred mice to people but the longest journey starts with one step

A vaccine might blunt or even prevent the deadly, memory-robbing devastation of Alzheimer's disease, a study has found. Scientists immunized mice with a molecule thought to play role in the illness. The treated mice, they said, showed better cognitive performance than unvaccinated mice, and a significant reduction in the buildup of protein plaques believed to cause brain cell death and dysfunction in Alzheimer's. "These results are extremely exciting," said Jordan Tang of the Oklahoma Medical Research Foundation, a nonprofit research institute, who led the study. The findings appear in The Journal of the Federation of American Societies for Experimental Biology.

Alzheimer's gradually ravages victims' memories and personalities by killing brain cells. The disease affects more than 5 million Americans, including nearly half the population over 85, according to the Alzheimer's Association.

Tang and colleagues previously had identified a moleculean enzyme called memapsin 2that cuts a protein into fragments which, in turn, are believed to cause Alzheimer's. In the new study, the group used memapsin 2 as a vaccine for mice genetically engineered to develop Alzheimer's symptoms. The mice "developed 35 percent fewer plaques," said Tang.

Tang's previous work also has led to the creation of an experimental drug that would treat Alzheimer's by inhibiting memapsin 2. Human clinical trials on that began last summer. Tang said a vaccine would be a supplement to, not a substitute for, other treatments of this nature. "Alzheimer's is a complicated, multifaceted disease," he said. "We cannot rely on a `onesizefitsall' strategy, because what works in one patient will not necessarily work in another."

Vaccination strategies, designed to stimulate the immune system to fight the plaques, have been considered a promising way forward, but their success has been limited, Tang said. In 2002, for example, the pharmaceutical company Elan halted trials of a different vaccine after 15 patients suffered swelling of the central nervous system.

But the new vaccine "stimulates the immune system more gently than previous Alzheimer's vaccines, so we are optimistic about its prospects," said Stephen Prescott, president of the foundation in Oklahoma city. The next step, said Tang, will be to progress toward human trials. "There currently is no effective treatment for Alzheimer's disease," he noted, "so we must explore every possible option."



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 condi-tions 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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