Why do some men who take Viagra for ED get heart attacks? It's not from the sudden excitement. If blood flow is impaired to certain parts of the body (such as your private parts) you can be sure it's impaired to other parts of the body; like your heart. This is a warning signal! Why do we always focus on a particular body part without looking at the whole picture?? Thankfully this research may shed light on this important (and impotent) issue and help save some lives.
Says BBC News, "Men with diabetes who are having trouble keeping an erection could be at increased risk of serious heart problems, suggests a study".
http://news.bbc.co.uk/2/hi/health/7405532.stm
If you have impaired blood flow and diabetes you need to immediatley consult with a nutritionist in addition to your medical doctors. A nutrition and activity program can help tremendously with these conditions, thereby reducing or eliminating your need for prescription meds, and hopefully enhancing the quality of your life without side effects. The last thing any couple wants is for the man to die of a heart attack, especially during sex.
Tuesday, May 20, 2008
Tuesday, May 06, 2008
Can You Become a Creature of New Habits?
The brain is able to remodel according to the input it receives. By taking small steps and achieving small sucesses you can stimulate the brain to lay down new pathways and become more robust. Do something you enjoy! This can be in the form of mental excercises such as crossword or wordsearch puzzles, physical activity such as walking, jumping rope, or a new sport, or a combination of physical and mental like playing the piano. Remember, do something that interests you and take small steps to avoid frustration and quitting too soon! You can do it!
From the NY Times:
May 4, 2008
By JANET RAE-DUPREE
HABITS are a funny thing. We reach for them mindlessly, setting our brains on auto-pilot and relaxing into the unconscious comfort of familiar routine. “Not choice, but habit rules the unreflecting herd,” William Wordsworth said in the 19th century. In the ever-changing 21st century, even the word “habit” carries a negative connotation.
So it seems antithetical to talk about habits in the same context as creativity and innovation. But brain researchers have discovered that when we consciously develop new habits, we create parallel synaptic paths, and even entirely new brain cells, that can jump our trains of thought onto new, innovative tracks.
Rather than dismissing ourselves as unchangeable creatures of habit, we can instead direct our own change by consciously developing new habits. In fact, the more new things we try — the more we step outside our comfort zone — the more inherently creative we become, both in the workplace and in our personal lives.
But don’t bother trying to kill off old habits; once those ruts of procedure are worn into the hippocampus, they’re there to stay. Instead, the new habits we deliberately ingrain into ourselves create parallel pathways that can bypass those old roads.
“The first thing needed for innovation is a fascination with wonder,” says Dawna Markova, author of “The Open Mind” and an executive change consultant for Professional Thinking Partners. “But we are taught instead to ‘decide,’ just as our president calls himself ‘the Decider.’ ” She adds, however, that “to decide is to kill off all possibilities but one. A good innovational thinker is always exploring the many other possibilities.”
All of us work through problems in ways of which we’re unaware, she says. Researchers in the late 1960s discovered that humans are born with the capacity to approach challenges in four primary ways: analytically, procedurally, relationally (or collaboratively) and innovatively. At puberty, however, the brain shuts down half of that capacity, preserving only those modes of thought that have seemed most valuable during the first decade or so of life.
The current emphasis on standardized testing highlights analysis and procedure, meaning that few of us inherently use our innovative and collaborative modes of thought. “This breaks the major rule in the American belief system — that anyone can do anything,” explains M. J. Ryan, author of the 2006 book “This Year I Will...” and Ms. Markova’s business partner. “That’s a lie that we have perpetuated, and it fosters mediocrity. Knowing what you’re good at and doing even more of it creates excellence.”
This is where developing new habits comes in. If you’re an analytical or procedural thinker, you learn in different ways than someone who is inherently innovative or collaborative. Figure out what has worked for you when you’ve learned in the past, and you can draw your own map for developing additional skills and behaviors for the future.
“I apprentice myself to someone when I want to learn something new or develop a new habit,” Ms. Ryan says. “Other people read a book about it or take a course. If you have a pathway to learning, use it because that’s going to be easier than creating an entirely new pathway in your brain.”
Ms. Ryan and Ms. Markova have found what they call three zones of existence: comfort, stretch and stress. Comfort is the realm of existing habit. Stress occurs when a challenge is so far beyond current experience as to be overwhelming. It’s that stretch zone in the middle — activities that feel a bit awkward and unfamiliar — where true change occurs.
“Getting into the stretch zone is good for you,” Ms. Ryan says in “This Year I Will... .” “It helps keep your brain healthy. It turns out that unless we continue to learn new things, which challenges our brains to create new pathways, they literally begin to atrophy, which may result in dementia, Alzheimer’s and other brain diseases. Continuously stretching ourselves will even help us lose weight, according to one study. Researchers who asked folks to do something different every day — listen to a new radio station, for instance — found that they lost and kept off weight. No one is sure why, but scientists speculate that getting out of routines makes us more aware in general.”
She recommends practicing a Japanese technique called kaizen, which calls for tiny, continuous improvements.
“Whenever we initiate change, even a positive one, we activate fear in our emotional brain,” Ms. Ryan notes in her book. “If the fear is big enough, the fight-or-flight response will go off and we’ll run from what we’re trying to do. The small steps in kaizen don’t set off fight or flight, but rather keep us in the thinking brain, where we have access to our creativity and playfulness.”
Simultaneously, take a look at how colleagues approach challenges, Ms. Markova suggests. We tend to believe that those who think the way we do are smarter than those who don’t. That can be fatal in business, particularly for executives who surround themselves with like-thinkers. If seniority and promotion are based on similarity to those at the top, chances are strong that the company lacks intellectual diversity.
“Try lacing your hands together,” Ms. Markova says. “You habitually do it one way. Now try doing it with the other thumb on top. Feels awkward, doesn’t it? That’s the valuable moment we call confusion, when we fuse the old with the new.”
AFTER the churn of confusion, she says, the brain begins organizing the new input, ultimately creating new synaptic connections if the process is repeated enough.
But if, during creation of that new habit, the “Great Decider” steps in to protest against taking the unfamiliar path, “you get convergence and we keep doing the same thing over and over again,” she says.
“You cannot have innovation,” she adds, “unless you are willing and able to move through the unknown and go from curiosity to wonder.”
Janet Rae-Dupree writes about science and emerging technology in Silicon Valley.
http://www.nytimes.com/2008/05/04/business/04unbox.html?_r=1&partner=rssyahoo&emc=rss&oref=slogin
From the NY Times:
May 4, 2008
By JANET RAE-DUPREE
HABITS are a funny thing. We reach for them mindlessly, setting our brains on auto-pilot and relaxing into the unconscious comfort of familiar routine. “Not choice, but habit rules the unreflecting herd,” William Wordsworth said in the 19th century. In the ever-changing 21st century, even the word “habit” carries a negative connotation.
So it seems antithetical to talk about habits in the same context as creativity and innovation. But brain researchers have discovered that when we consciously develop new habits, we create parallel synaptic paths, and even entirely new brain cells, that can jump our trains of thought onto new, innovative tracks.
Rather than dismissing ourselves as unchangeable creatures of habit, we can instead direct our own change by consciously developing new habits. In fact, the more new things we try — the more we step outside our comfort zone — the more inherently creative we become, both in the workplace and in our personal lives.
But don’t bother trying to kill off old habits; once those ruts of procedure are worn into the hippocampus, they’re there to stay. Instead, the new habits we deliberately ingrain into ourselves create parallel pathways that can bypass those old roads.
“The first thing needed for innovation is a fascination with wonder,” says Dawna Markova, author of “The Open Mind” and an executive change consultant for Professional Thinking Partners. “But we are taught instead to ‘decide,’ just as our president calls himself ‘the Decider.’ ” She adds, however, that “to decide is to kill off all possibilities but one. A good innovational thinker is always exploring the many other possibilities.”
All of us work through problems in ways of which we’re unaware, she says. Researchers in the late 1960s discovered that humans are born with the capacity to approach challenges in four primary ways: analytically, procedurally, relationally (or collaboratively) and innovatively. At puberty, however, the brain shuts down half of that capacity, preserving only those modes of thought that have seemed most valuable during the first decade or so of life.
The current emphasis on standardized testing highlights analysis and procedure, meaning that few of us inherently use our innovative and collaborative modes of thought. “This breaks the major rule in the American belief system — that anyone can do anything,” explains M. J. Ryan, author of the 2006 book “This Year I Will...” and Ms. Markova’s business partner. “That’s a lie that we have perpetuated, and it fosters mediocrity. Knowing what you’re good at and doing even more of it creates excellence.”
This is where developing new habits comes in. If you’re an analytical or procedural thinker, you learn in different ways than someone who is inherently innovative or collaborative. Figure out what has worked for you when you’ve learned in the past, and you can draw your own map for developing additional skills and behaviors for the future.
“I apprentice myself to someone when I want to learn something new or develop a new habit,” Ms. Ryan says. “Other people read a book about it or take a course. If you have a pathway to learning, use it because that’s going to be easier than creating an entirely new pathway in your brain.”
Ms. Ryan and Ms. Markova have found what they call three zones of existence: comfort, stretch and stress. Comfort is the realm of existing habit. Stress occurs when a challenge is so far beyond current experience as to be overwhelming. It’s that stretch zone in the middle — activities that feel a bit awkward and unfamiliar — where true change occurs.
“Getting into the stretch zone is good for you,” Ms. Ryan says in “This Year I Will... .” “It helps keep your brain healthy. It turns out that unless we continue to learn new things, which challenges our brains to create new pathways, they literally begin to atrophy, which may result in dementia, Alzheimer’s and other brain diseases. Continuously stretching ourselves will even help us lose weight, according to one study. Researchers who asked folks to do something different every day — listen to a new radio station, for instance — found that they lost and kept off weight. No one is sure why, but scientists speculate that getting out of routines makes us more aware in general.”
She recommends practicing a Japanese technique called kaizen, which calls for tiny, continuous improvements.
“Whenever we initiate change, even a positive one, we activate fear in our emotional brain,” Ms. Ryan notes in her book. “If the fear is big enough, the fight-or-flight response will go off and we’ll run from what we’re trying to do. The small steps in kaizen don’t set off fight or flight, but rather keep us in the thinking brain, where we have access to our creativity and playfulness.”
Simultaneously, take a look at how colleagues approach challenges, Ms. Markova suggests. We tend to believe that those who think the way we do are smarter than those who don’t. That can be fatal in business, particularly for executives who surround themselves with like-thinkers. If seniority and promotion are based on similarity to those at the top, chances are strong that the company lacks intellectual diversity.
“Try lacing your hands together,” Ms. Markova says. “You habitually do it one way. Now try doing it with the other thumb on top. Feels awkward, doesn’t it? That’s the valuable moment we call confusion, when we fuse the old with the new.”
AFTER the churn of confusion, she says, the brain begins organizing the new input, ultimately creating new synaptic connections if the process is repeated enough.
But if, during creation of that new habit, the “Great Decider” steps in to protest against taking the unfamiliar path, “you get convergence and we keep doing the same thing over and over again,” she says.
“You cannot have innovation,” she adds, “unless you are willing and able to move through the unknown and go from curiosity to wonder.”
Janet Rae-Dupree writes about science and emerging technology in Silicon Valley.
http://www.nytimes.com/2008/05/04/business/04unbox.html?_r=1&partner=rssyahoo&emc=rss&oref=slogin
Evidence a High-Fat Diet Works to Treat Epilepsy
A idea of a hig fat diet to treat epilepsy has been around since the 1920s and has often been dismissed by the medical community. A new British study shows good evidence that it works. I wonder how well essential fatty acids from fish oils and other quality fats like avocado, coconut, and flax would work compared to the highly saturated animal fats that were tested.
From The New York Times:
May 6, 2008
By ALIYAH BARUCHIN
A formerly controversial high-fat diet has proved highly effective in reducing seizures in children whose epilepsy does not respond to medication, British researchers are reporting.
As the first randomized trial of the diet, the new study lends legitimacy to a treatment that has been used since the 1920s but has until recently been dismissed by many doctors as a marginal alternative therapy.
“This is the first time that we’ve really got Class 1 evidence that this diet works for treatment of epilepsy,” said Dr. J. Helen Cross, professor of pediatric neurology at University College London and Great Ormond Street Hospital. She is a principal investigator on the study, which will appear in the June issue of The Lancet Neurology.
Though its exact mechanism is uncertain, the diet appears to work by throwing the body into ketosis, forcing it to burn fat rather than sugar for energy. Breakfast on the diet might consist of bacon, eggs with cheese, and a cup of heavy cream diluted with water; some children drink oil to obtain the fats that they need. Every gram of food is weighed, and carbohydrates are almost entirely restricted. Breaking the diet with so much as a few cookies can cause seizures to flare up.
For the British trial, the researchers enrolled 145 children ages 2 to 16 who had never tried the diet, who were having at least seven seizures a week and who had failed to respond to at least two anticonvulsant drugs.
One group began the ketogenic diet immediately. The control group waited three months before starting it. In the first group, 38 percent of the children had seizure rates reduced by half, compared with 6 percent in the control group. Five children in the diet group had reductions exceeding 90 percent.
Perceptions of the diet have changed sharply in the last decade. In 1993, a Hollywood producer, Jim Abrahams, took his 1-year-old son, Charlie, to Dr. John M. Freeman at the Pediatric Epilepsy Center at Johns Hopkins, which was one of the few centers championing the diet. Within three days of starting the diet, Charlie’s incapacitating seizures, which had resisted multiple medications and surgery, stopped entirely.
With his wife, Nancy, Mr. Abrahams founded the Charlie Foundation to Help Cure Pediatric Epilepsy to promote education about the diet. He produced an instructional video for parents and a made-for-television movie, “First Do No Harm,” starring Meryl Streep as a mother who seeks out the diet for her child.
As a result of the Johns Hopkins work, research on the diet blossomed and it became a standard treatment at hospitals and epilepsy centers in the United States and abroad.
Dr. Shlomo Shinnar, director of the Comprehensive Epilepsy Management Center at the Montefiore Medical Center in the Bronx, called the new study “an important trial that lays to rest the issue of ‘Does it really work or not?’ ”
Although the diet has to be medically supervised, Dr. Shinnar said, it is a mistake to believe that it requires extensive hospital resources and a staff’s constant attention. “Here they don’t have this,” he said of the British trial. “This study makes it clear that this actually can be made to work in a community setting.”
From The New York Times:
May 6, 2008
By ALIYAH BARUCHIN
A formerly controversial high-fat diet has proved highly effective in reducing seizures in children whose epilepsy does not respond to medication, British researchers are reporting.
As the first randomized trial of the diet, the new study lends legitimacy to a treatment that has been used since the 1920s but has until recently been dismissed by many doctors as a marginal alternative therapy.
“This is the first time that we’ve really got Class 1 evidence that this diet works for treatment of epilepsy,” said Dr. J. Helen Cross, professor of pediatric neurology at University College London and Great Ormond Street Hospital. She is a principal investigator on the study, which will appear in the June issue of The Lancet Neurology.
Though its exact mechanism is uncertain, the diet appears to work by throwing the body into ketosis, forcing it to burn fat rather than sugar for energy. Breakfast on the diet might consist of bacon, eggs with cheese, and a cup of heavy cream diluted with water; some children drink oil to obtain the fats that they need. Every gram of food is weighed, and carbohydrates are almost entirely restricted. Breaking the diet with so much as a few cookies can cause seizures to flare up.
For the British trial, the researchers enrolled 145 children ages 2 to 16 who had never tried the diet, who were having at least seven seizures a week and who had failed to respond to at least two anticonvulsant drugs.
One group began the ketogenic diet immediately. The control group waited three months before starting it. In the first group, 38 percent of the children had seizure rates reduced by half, compared with 6 percent in the control group. Five children in the diet group had reductions exceeding 90 percent.
Perceptions of the diet have changed sharply in the last decade. In 1993, a Hollywood producer, Jim Abrahams, took his 1-year-old son, Charlie, to Dr. John M. Freeman at the Pediatric Epilepsy Center at Johns Hopkins, which was one of the few centers championing the diet. Within three days of starting the diet, Charlie’s incapacitating seizures, which had resisted multiple medications and surgery, stopped entirely.
With his wife, Nancy, Mr. Abrahams founded the Charlie Foundation to Help Cure Pediatric Epilepsy to promote education about the diet. He produced an instructional video for parents and a made-for-television movie, “First Do No Harm,” starring Meryl Streep as a mother who seeks out the diet for her child.
As a result of the Johns Hopkins work, research on the diet blossomed and it became a standard treatment at hospitals and epilepsy centers in the United States and abroad.
Dr. Shlomo Shinnar, director of the Comprehensive Epilepsy Management Center at the Montefiore Medical Center in the Bronx, called the new study “an important trial that lays to rest the issue of ‘Does it really work or not?’ ”
Although the diet has to be medically supervised, Dr. Shinnar said, it is a mistake to believe that it requires extensive hospital resources and a staff’s constant attention. “Here they don’t have this,” he said of the British trial. “This study makes it clear that this actually can be made to work in a community setting.”
Fat Cells Die and Are Replaced
Fat cells never go away! Arrrghh! If you lose weight they're just waiting for you to eat that bag of potatoe chips to fill up again! You just can't get away from being active, getting a good night's sleep, and a proper diet.
From the New York Times:
May 5, 2008
Study Finds That Fat Cells Die and Are Replaced
By GINA KOLATA
Every year, whether you are fat or thin, whether you lose weight or gain, 10 percent of your fat cells die. And every year, those cells that die are replaced with new fat cells, researchers in Sweden reported Sunday.
The result is that the total number of fat cells in the body remains the same, year after year throughout adulthood. Losing or gaining weight affects only the amount of fat stored in the cells, not the number of cells.
The finding was published online Sunday in the journal Nature.
Obesity investigators say the study raises tantalizing questions: What determines how many fat cells are in a person’s body? When is that number determined? Is there a way to intervene so people end up with fewer fat cells when they reach adulthood? And could obesity be treated by making fat cells die faster than they are born?
“This is a new way of looking at obesity,” said Dr. Lester Salans, an obesity researcher and emeritus professor at Mount Sinai School of Medicine in New York.
But for now, researchers say, they do not have a clue about how to answer those questions.
“There is a system waiting to be discovered,” said Dr. Jeffrey S. Flier, an obesity researcher and dean of Harvard Medical School.
Dr. Flier and other obesity researchers cautioned, though, that even if scientists knew how the fat cell system worked, it was not clear that it would be safe or effective to treat obesity by intervening. One of the hard lessons of the past couple of decades has been that the body has redundant controls to maintain weight.
“I suspect that the body’s regulation of weight is so complex that if you intervene at this site, something else is going to happen to neutralize this intervention,” Dr. Salans said.
But the discovery is also leading to new ways to address other questions about obesity. For example, what happens to people who are thin until adulthood and then gain a lot of weight? The study focused on people who had been fat since childhood, the usual route for adult obesity. The situation may be different for people who got fat later. They may actually grow new fat cells — the ones they had may have become so stuffed with fat that they could hold no more.
Another question is whether fat cells removed with liposuction grow back.
Both questions are now under investigation by the Swedish researchers.
In a way, Dr. Flier noted, the discovery is a sort of back-to-the-future moment. There was a time a few decades ago, before the current interest in how the brain regulates how much is eaten, when obesity researchers spent all their time studying and discussing fat cells. Investigators discovered that fat people had more fat cells than thin people and that fat cells shrank with weight loss and bulged with weight gain.
Dr. Jules Hirsch of Rockefeller University in New York, who did many of the initial studies with humans, said he started because he could not understand why people who lost weight regained. “They should have been cured,” Dr. Hirsch said. After all, he said, if you cut out a fatty tumor, the fat does not grow back. Why was fat lost from dieting different?
The result was the fat cell hypothesis, a notion that obsessed researchers. Fat cells, the hypothesis said, are laid down early in life and after that, they can change only in size, not in number. When people lose weight and their fat cells shrink, that creates a signal to fill the cells again, making people regain. “We didn’t know a lot about obesity, so that was what we talked about,” Dr. Flier said.
But the discussions stalled. It was not clear what to do about those discoveries or what they meant to efforts to help people lose weight. And no one had a method to ask whether fat cells were being created and destroyed during life. Few even thought to ask that question.
That changed only recently when the new paper’s first author, Kirsty L. Spalding, a neurobiologist at the Karolinska Institute in Sweden, developed a way to ask whether new cells grow in the cortical and cerebellum regions of the human brain. She found no new cells there since birth. One day, she was giving a talk on her brain study when a scientist in the audience, Erik Arner, suggested she use the method to look at fat cells. (Dr. Arner is the second author of Dr. Spalding’s paper.) The method for dating human cells takes advantage of an effect caused by above-ground nuclear bomb testing that took place from 1955 to 1963.
When the bombs were tested, their radioactivity created a spike in the amount of a carbon isotope, C14, in the atmosphere. The C14 made its way into plants and animals that ate the plants. When people ate those plants and meat from the animals, the C14 was incorporated into their human DNA. After the nuclear test ban, C14 levels started to drop. The result is that every cell has a C14 level that reflects the level in the atmosphere at the time the cell was born.
“Each cell is a time capsule of sorts,” Dr. Spalding said.
First the researchers confirmed that the number of fat cells remained constant in adults. Obese people who had weight loss surgery had as many fat cells two years after the surgery as before it, even though they were much thinner.
Then the investigators asked whether fat cells were being born and dying. To do that, they examined fat cells taken from 35 people, fat and lean, who had had liposuction or abdominal wall reconstruction. The amount of C14 in the cells would reveal how old the cells were. Since the number of fat cells remained constant, the number being born had to equal the number dying. And a mathematical model would reveal the dynamics of the cell turnover.
“We found the cells were really quite young,” Dr. Spalding said. “That tells us new cells are being born.”
She added: “The million-dollar question now is, What regulates this process? And where can we intervene?”
From the New York Times:
May 5, 2008
Study Finds That Fat Cells Die and Are Replaced
By GINA KOLATA
Every year, whether you are fat or thin, whether you lose weight or gain, 10 percent of your fat cells die. And every year, those cells that die are replaced with new fat cells, researchers in Sweden reported Sunday.
The result is that the total number of fat cells in the body remains the same, year after year throughout adulthood. Losing or gaining weight affects only the amount of fat stored in the cells, not the number of cells.
The finding was published online Sunday in the journal Nature.
Obesity investigators say the study raises tantalizing questions: What determines how many fat cells are in a person’s body? When is that number determined? Is there a way to intervene so people end up with fewer fat cells when they reach adulthood? And could obesity be treated by making fat cells die faster than they are born?
“This is a new way of looking at obesity,” said Dr. Lester Salans, an obesity researcher and emeritus professor at Mount Sinai School of Medicine in New York.
But for now, researchers say, they do not have a clue about how to answer those questions.
“There is a system waiting to be discovered,” said Dr. Jeffrey S. Flier, an obesity researcher and dean of Harvard Medical School.
Dr. Flier and other obesity researchers cautioned, though, that even if scientists knew how the fat cell system worked, it was not clear that it would be safe or effective to treat obesity by intervening. One of the hard lessons of the past couple of decades has been that the body has redundant controls to maintain weight.
“I suspect that the body’s regulation of weight is so complex that if you intervene at this site, something else is going to happen to neutralize this intervention,” Dr. Salans said.
But the discovery is also leading to new ways to address other questions about obesity. For example, what happens to people who are thin until adulthood and then gain a lot of weight? The study focused on people who had been fat since childhood, the usual route for adult obesity. The situation may be different for people who got fat later. They may actually grow new fat cells — the ones they had may have become so stuffed with fat that they could hold no more.
Another question is whether fat cells removed with liposuction grow back.
Both questions are now under investigation by the Swedish researchers.
In a way, Dr. Flier noted, the discovery is a sort of back-to-the-future moment. There was a time a few decades ago, before the current interest in how the brain regulates how much is eaten, when obesity researchers spent all their time studying and discussing fat cells. Investigators discovered that fat people had more fat cells than thin people and that fat cells shrank with weight loss and bulged with weight gain.
Dr. Jules Hirsch of Rockefeller University in New York, who did many of the initial studies with humans, said he started because he could not understand why people who lost weight regained. “They should have been cured,” Dr. Hirsch said. After all, he said, if you cut out a fatty tumor, the fat does not grow back. Why was fat lost from dieting different?
The result was the fat cell hypothesis, a notion that obsessed researchers. Fat cells, the hypothesis said, are laid down early in life and after that, they can change only in size, not in number. When people lose weight and their fat cells shrink, that creates a signal to fill the cells again, making people regain. “We didn’t know a lot about obesity, so that was what we talked about,” Dr. Flier said.
But the discussions stalled. It was not clear what to do about those discoveries or what they meant to efforts to help people lose weight. And no one had a method to ask whether fat cells were being created and destroyed during life. Few even thought to ask that question.
That changed only recently when the new paper’s first author, Kirsty L. Spalding, a neurobiologist at the Karolinska Institute in Sweden, developed a way to ask whether new cells grow in the cortical and cerebellum regions of the human brain. She found no new cells there since birth. One day, she was giving a talk on her brain study when a scientist in the audience, Erik Arner, suggested she use the method to look at fat cells. (Dr. Arner is the second author of Dr. Spalding’s paper.) The method for dating human cells takes advantage of an effect caused by above-ground nuclear bomb testing that took place from 1955 to 1963.
When the bombs were tested, their radioactivity created a spike in the amount of a carbon isotope, C14, in the atmosphere. The C14 made its way into plants and animals that ate the plants. When people ate those plants and meat from the animals, the C14 was incorporated into their human DNA. After the nuclear test ban, C14 levels started to drop. The result is that every cell has a C14 level that reflects the level in the atmosphere at the time the cell was born.
“Each cell is a time capsule of sorts,” Dr. Spalding said.
First the researchers confirmed that the number of fat cells remained constant in adults. Obese people who had weight loss surgery had as many fat cells two years after the surgery as before it, even though they were much thinner.
Then the investigators asked whether fat cells were being born and dying. To do that, they examined fat cells taken from 35 people, fat and lean, who had had liposuction or abdominal wall reconstruction. The amount of C14 in the cells would reveal how old the cells were. Since the number of fat cells remained constant, the number being born had to equal the number dying. And a mathematical model would reveal the dynamics of the cell turnover.
“We found the cells were really quite young,” Dr. Spalding said. “That tells us new cells are being born.”
She added: “The million-dollar question now is, What regulates this process? And where can we intervene?”
Subscribe to:
Posts (Atom)