Harvard cooks the books on weight and mortality

the scientific evidence for higher mortality for overweight BMI may go back decades - but online evidence is limited

clipped from www.tnr.com The story is simple: That it's well-established scientific fact that being "overweight"--that is, having a body mass index figure of between 25 and 30--is, in the words of Harvard professors Walter Willett and Meir Stampfer, "a major contributor to morbidity and mortality." According to this line of argument, there's simply no real scientific dispute about the "fact" that average-height women who weigh between 146 and a 174 pounds, and average-height men who weigh between 175 and 209 pounds, are putting their lives and health at risk. t's difficult to exaggerate the extent to which the actual scientific evidence fails to support any of this. In fact, the current evidence suggests that what the Harvard crew is saying is not merely false, but closer to the precise opposite of the truth. For the most part, the so-called "overweight" BMI range doesn't even correlate with overall increased health risk. Indeed "overweight," so-called, often correlates with the lowest mortality rates.

Cancer doubt remains over mobiles

reposted from bbc

Cancer doubt remains over mobiles

Campaigners fear mobile phones damage health

The long-term cancer risk of mobile phone use cannot be ruled out, experts have concluded.

A major six-year research programme found a "hint" of a higher cancer risk.

But the UK Mobile Telecommunications and Health Research Programme (MTHRP) did rule out short-term adverse effects to brain and cell function.

Researchers are now expanding the programme to look at phone use over 10 years, and the specific impact on children, which has not been studied.

The MTHRP programme, funded by the government and communications industry, has carried out 23 separate studies into the health impact of mobile phones, masts and base stations.

We can't rule out the possibility at this stage that cancer could appear in a few years' time Professor Lawrie Challis Q&A: Mobile phone safety

Programme chairman Professor Lawrie Challis said it was now up to the government to offer advice.

The team found that there was a slight excess reporting of brain and acoustic neuroma (ear) cancers.

Researchers said this was on the borderline of statistical significance.

Professor Challis said that it was only responsible to do more research, citing the way smoking was not linked to lung cancer at first.

Time will tell

He said: "We can't rule out the possibility at this stage that cancer could appear in a few years' time.

"With smoking there was no link of any lung cancer until after ten years."

He said the problem during the study was that there had been very few people using mobile phones for over ten years.

Cancers do not normally appear until ten to 15 years after exposure.

But he said overall the evidence that mobiles did not pose a significant health risk was "pretty reassuring".

The current precautionary approach - involving limited restrictions on mast-siting relating to schools for example and advice about limiting use by young children - is reasonable Dr Evan Harris, of the Lib Dems

The team looked at factors affecting blood pressure, heart rate, and electrical hypersensitivity, which include symptoms such as headaches, dizziness and tingling.

They concluded there was no risk.

It was established following publication of an independent government-commissioned report into the safety of mobile phones in 2000.

The report, produced by a group led by Sir William Stewart, concluded that mobile phones did not appear to harm health - but recommended further research was carried out.

However, in 2005 Sir William warned that mobile phone use by children should be limited as a precaution - and that under-eights should not use them at all.

There are now 70 million mobile phone handsets in the UK, and around 50 thousand masts.

Both emit radio signals and electromagnetic fields that can penetrate the human brain, and campaigners fear that this could seriously damage human health.

Lib Dem science spokesman Dr Evan Harris said the findings were "good news for the public", but it was only right more research was carried out.

"The current precautionary approach - involving limited restrictions on mast-siting relating to schools for example and advice about limiting use by young children - is reasonable and this research demonstrates that there is as yet no justification for a more restrictive approach."

But a spokeswoman for the Mast Sanity campaign group said: "We believe mobiles are harmful to health, plenty of other studies have shown this.

"The programme has not really got to the bottom of this, it is too close to industry."

Keeping your teeth clean could help prevent a heart attack, claim doctors

clipped from www.dailymail.co.uk Brushing and flossing your teeth could save you from a heart attack, claim experts. Doctors found those with the worst blockages in their arteries had the most severe gum disease. There is mounting evidence of a link between gum disease and heart disease, but a study claims to be the first to show that the severity of each disease may also be connected. Chronic gum disease is called periodontitis, which occurs when waste material or plaque collects around the teeth and irritates the gums. Plaque is removed when teeth are looked after properly. It is not clear how gum disease may trigger heart problems, although it is thought that bacteria released from the infected gums are the key. The bacteria enter the bloodstream where they may activate the immune system, making artery walls inflamed and narrowed, or attach directly to fatty deposits already present in the arteries which causes further narrowing. "The most severe teeth disease was associated with the most widespread arterial lesions,"

Gene 'controls body fat levels'

reposted from bbc

Gene 'controls body fat levels'

Obesity may be at least partly in the genes

A single gene can keep in check the tendency to pile on fat, scientists have shown.

The University of Texas team manipulated the gene, called adipose, to alter the amount of fat tissue laid down by fruit flies, worms and mice.

If the same effect could be achieved in humans, which also carry the gene, it is hoped it could lead to new ways to fight obesity and diabetes.

The study is published in the journal Cell Metabolism.

Maybe if you could affect this gene, even just a little bit, you might have a beneficial effect on fat Dr Jonathan Graff University of Texas

Lead researcher Dr Jonathan Graff said: "From worms to mammals, this gene controls fat formation.

"It could explain why so many people struggle to lose weight, and suggests an entirely new direction for developing medical treatments that address the current epidemic of diabetes and obesity.

"Maybe if you could affect this gene, even just a little bit, you might have a beneficial effect on fat."

The adipose gene was discovered in fat fruit flies more than 50 years ago, but scientists had not pinned down its exact role.

The Texas team used several methods to turn the gene on and off at different stages of the animals' lives and in various parts of their bodies.

Their work suggested that

the gene acts as a high-level master switch that tells the body whether to accumulate or burn fat.

Health impact

Mice with experimentally increased adipose activity ate as much or more than normal mice.

However, they were leaner, had diabetes-resistant fat cells, and were better able to control insulin and blood-sugar metabolism.

In contrast, animals with reduced adipose activity were fatter and less healthy, and had diabetes.

The researchers also showed that gene activity could be turned up or down, not just on or off.

Dr Graff said this increased the potential to manipulate its effect to treat obesity.

The next step will be to probe further the exact mechanisms by which the gene exerts its control.

Dr David Haslam, clinical director of the National Obesity Forum, warned that

it could take many years to develop genetic treatments for obesity.

In the meantime, he said, the only way to tackle the problem effectively was to encourage people to eat healthily and take exercise.

"I don't want patients coming to me saying: 'It's not what I eat, it's all in my genes'," he said.

"Don't give my patients another excuse to be victims."

End of Aging -The Next Great Paradigm Shift?

reposted from Daily Galaxy

September 05, 2007

End of Aging -The Next Great Paradigm Shift?

In his new non-fiction Amazon bestseller, Ending Aging, Aubrey de Grey, champions recent progress in genetics and calorie-restricted diets in laboratory animals that hold forth the promise that someday science will enable us to exert total control over our own biological aging and substantially slow down the aging process.

Aubrey de Grey is convinced that he has formulated the theoretical means by which human beings might live thousands of years -- indefinitely, in fact.

Like Francis Bacon, de Grey has never stationed himself at a laboratory bench to attempt a ­single hands-on experiment, at least not in human biology. He is a computer scientist who has taught himself natural science, and has set himself toward the goal of transforming the basis of what it means to be human.

Dr. de Grey, who holds a rare University of Cambridge degree on this basis of publications rather than classwork, believes that the key biomedical technology required to eliminate aging-derived debilitation and death entirely is now within reach —technology that would not only slow but periodically reverse age-related physiological decay, leaving us biologically young into an indefinite future—is now within reach.

In Ending Aging, Dr. de Grey and his research assistant Michael Rae describe the details of this biotechnology. They explain that the aging of the human body, similar to the aging of man-made machines, results from an accumulation of various types of damage. And, as with machines, this damage can periodically be repaired, leading to indefinite extension of the machine’s fully functional lifetime.

By demystifying aging and its postponement for the nonspecialist reader, de Grey and Rae systematically dismantle the fatalist presumption that aging will forever defeat the efforts of medical science.

The most realistic way to combat aging, de Gray suggests, is to rejuvenate the body at the molecular and cellular level, removing accumulated damage and restoring us to a biologically younger state. Comprehensive rejuvenation therapies can feasibly postpone age-related frailty and disease indefinitely, greatly extending our lives while eliminating, rather than lengthening, the period of late-life frailty and debilitation.

"The real issue," de Grey writes, "surely, was not which metabolic processes cause aging damage in the body, but the damage itself. Forty-year-olds have fewer healthy years to look forward to than twenty-year-olds because of differences in their molecular and cellular composition, not because of the mechanisms that gave rise to those differences. How far could I narrow down the field of candidate causes of aging by focusing on the molecular damage itself?"

Removing the causes of aging-related deaths will also eliminate all the suffering that aging inflicts on most people in the last years of their lives. Aging kills 100,000 people a day. Social concerns about the effects of defeating aging are legitimate but don’t outweigh the merits of saving so many lives and alleviating so much suffering.

"There are mutations in our chromosomes, of course, which cause cancer," de Grey muses. "There is glycation, the warping of proteins by glucose. There are the various kinds of junk that accumulate outside the cell (“extracellular aggregates”): beta-amyloid, the lesser-known transthyretin, and possibly other substances of the same general sort. There is also the unwholesome goo that builds up within the cell (“intracellular aggregates”), such as lipofuscin. There’s cellular senescence, the “aging” of individual cells, which puts them into a state of arrested growth and causes them to produce chemical signals dangerous to their neighbors. And there’s the depletion of the stem cell pools essential to healing and maintenance of tissue.

"And of course, there are mitochondrial mutations, which seem to disrupt cellular biochemistry by increasing oxidative stress. I had for a few years felt optimistic that scientists could solve this problem by copying mitochondrial DNA from its vulnerable spot at “ground zero,” within the free-radical generating mitochondria, into the bomb shelter of the cell nucleus, where damage to DNA is vastly rarer.

"Now, if only we had solutions like that for all of this other stuff, I mused, we could forget about the “butterfly effect” of interfering with basic metabolic processes, and just take the damage ITSELF out of the picture."

De Grey's call to action, writes Dr. Sherwin Nuland, clinical professor of surgery at Yale University School of Medicine and author of How We Die and The Art of Aging, "is the message neither of a madman nor a bad man, but of a brilliant, beneficent man of goodwill, who wants only for civilization to fulfill the highest hopes he has for its future.” An opinion darkly countered by Dr. Martin Raff, emeritus professor of biology at University College London and coauthor of Molecular Biology of the Cell: “Seems to me this man could be put in jail with reasonable cause.”

De Grey has formulated a wide-ranging plan for the comprehensive and eventually indefinite postponement of age-related physical and mental decline, named SENS (Strategies for Engineered Negligible Senescence). He is the organizer of an ongoing series of conferences and workshops that focus on the key biomedical research relevant to SENS, and he also oversees the Methuselah Foundation’s growing sponsorship of SENS research worldwide.

"For decades," de grey summarized, "my colleagues and I had been earnestly investigating aging in the same way that historians might “investigate” World War I: as an almost hopelessly complex historical tragedy about which everyone could theorize and argue, but about which nothing could fundamentally be done. Perhaps inhibited by the deeply ingrained belief that aging was “natural” and “inevitable,” biogerontologists had set themselves apart from the rest of the biomedical community by allowing themselves to be overawed by the complexity of the phenomenon that they were observing.

"To intervene in aging, I realized, didn’t require a complete understanding of all the myriad interacting processes that contribute to aging damage. To design therapies, all you have to understand is aging damage itself: the molecular and cellular lesions that impair the structure and function of the body’s tissues. Once I realized that simple truth, it became clear that we are far closer to real solutions to treating aging as a biomedical problem, amenable to therapy and healing, than it might otherwise seem."

Posted by Casey Kazan.

Related Galaxy posts:

The Story of a Biologist & the Extension of the Human Life Span
Pathway to Longevity Discovered
Can Humans Live to 1,000? Some Experts Claim We Can — Others Want to Prevent That
Darwin's Lab: Scientists on Brink of Creating Life
World's Oldest Living Microbes May Cast Light on Aging & Life on Mars
“Longevity Genes” Solve Centenarian Paradox
The "Blue Brain" & Human Consciousness -Scientists Create Artificial Brain
"Mind Children": Transhumanism & the Search For Genetic Perfection
“What is Life?” A New Breed of Robots Are Causing Scientists to Question

Video: Aubrey de Grey -Defeat of Aging

http://www.technologyreview.com/Biotech/14147/