博文
Saving the Rainforests for Future Generations
Rainforests are being cut and burned form Brazil to Indonesia at such a rate that they could well disappear from the earth's surface before the year 2050. They are being cleared for valuable timber and other resources to speed up the economic growth of the nations in which they are located. The most recent figures show that the area of rainforest destroyed last year alone was bigger than the size of Great Britain and Ireland.
If the present rate of deforestation is allowed to continue, the consequences for the earth will be great. We shall see a massive upsetting of ecosystems, very large increases in soil erosion, increases in flooding and in drought, changes in rainfall patterns and regional, quite possibly global, changes in climate. We shall also probably lose many rare plant and animal species.
According to many scientists, the burning of rainforests is also directly contributing to the so-called greenhouse effect. This effect, they say, is raising average temperatures and sea levels as the polar ice caps recede.
The rainforest is essential in other areas also. It is a medicine chest of unlimited potential. The US National Cancer Institute has identified 2,000 rainforest plants which could be beneficial in fighting cancer. In today's pharmaceutical market, 15 of the 125 drugs derived from plants were discovered in the rainforest.
Plant species are not the only forms of life threatened with extinction in the rainforest. Rare birds and animals that cannot be found anywhere else in the world have been disappearing at the rate of one a year since the turn of the century.
In the face of all these facts, it seems senseless for countries to continue destroying their rainforests. However, the problem is not so simple. The countries in which the rainforests are located are all quite poor and overpopulated. One of them, Brazil, has a population of 140 million, about half of whom are living in absolute poverty. The governments in these countries are usually also too weak to stop large companies and powerful individuals from destroying the rainforests. They have no money, so when the poor whom they cannot feed find work cutting down trees or burning forestland, the governments often have no choice but to turn a blind eye. Moreover, for many of these countries, the valuable timber and other resources found in the rainforests are also a very important source of foreign exchange, which they badly need to pay off their foreign debts and purchase foreign equipment and other goods.
The only solution to the problem, then, seems to be for the richer countries of the world to help the countries where the rainforests are located. One way they could help would be by cancelling the international debts that countries like Brazil owe, while also working together with these countries to solve their other economic problems. At the same time, they could support programmes to teach the local people to regard the rainforests as gardens to be harvested, and not merely as places where the only way for them to make a living is by senselessly cutting down trees and burning.
Such programmes could teach the local people how to select trees worth exporting and to cut only those trees down while leaving the rest, so that the basic make-up of the forest would not be disturbed. This would also mean that the environment needed for the survival of the many rare species of animals and plants, as well as of the Indian tribes that live in the rainforest, could be preserved. The local people could also be taught to earn more money by cutting the selected trees and making them into furniture on the spot. In addition, they could learn how to harvest other valuable natural materials that are now being wasted, and sell them overseas to earn foreign exchange for their countries.
Last but not least, people in the richer countries of the world could also help save the rainforests by using wood-derived products such as paper more carefully and by recycling used paper products to help reduce the demand for newly cut wood.
StrawberryNET
2008年6月24日
Study adds data that vegetables reduce cancer risk
Study adds data that vegetables reduce cancer risk
Do you want one?
New research is strengthening evidence that following mom's admonition to eat your vegetables may be some of the best health advice around.
A large study of 500,000 American retirees has found that just one extra serving of fruit or vegetables a day may reduce the risk of developing head and neck cancer.
Numerous studies have demonstrated that diet plays a role in cancer. Cancer experts now believe that up to two-thirds of all cancers come from lifestyle factors such as smoking, diet and lack of exercise.
"It may not sound like news that vegetables protect from cancer, but there is actually some controversy in the literature. It is important that we do these large studies," said Dr. Alan Kristal, associate head of the cancer prevention program at Fred Hutchinson Cancer Research Center in Seattle.
Researchers at the National Cancer Institute queried men and women aged 50 and older about their diets, then followed participants for five years to record all diagnoses of head and neck cancer, which is the sixth-leading cause of cancer-related death worldwide.
Tobacco and alcohol use increase the risk of head and neck cancers, which affect the mouth, nose, sinuses and throat.
The study found eating six servings of fruit and vegetables per day per 1,000 calories cut the risk of head and neck cancer by 29 percent compared to eating one and a half servings.
The typical adult consumes around 2,000 calories a day.
"Increasing consumption by just one serving of fruit or vegetables per 1,000 calories per day was associated with a 6 percent reduction in head and neck cancer risk, said Neal Freedman, cancer prevention fellow at the NCI.
A second study of food consumption in more than 183,000 residents of California and Hawaii found that a diet high in flavonols might help reduce pancreatic cancer risk, especially in smokers.
Flavonols are common in plant-based foods but are found in highest concentrations in onions, apples, berries, kale and broccoli.
The study found that people who ate the largest amounts of flavonols had a 23 percent reduced risk of developing pancreatic cancer compared to those who ate the least.
Do you want one?
New research is strengthening evidence that following mom's admonition to eat your vegetables may be some of the best health advice around.
A large study of 500,000 American retirees has found that just one extra serving of fruit or vegetables a day may reduce the risk of developing head and neck cancer.
Numerous studies have demonstrated that diet plays a role in cancer. Cancer experts now believe that up to two-thirds of all cancers come from lifestyle factors such as smoking, diet and lack of exercise.
"It may not sound like news that vegetables protect from cancer, but there is actually some controversy in the literature. It is important that we do these large studies," said Dr. Alan Kristal, associate head of the cancer prevention program at Fred Hutchinson Cancer Research Center in Seattle.
Researchers at the National Cancer Institute queried men and women aged 50 and older about their diets, then followed participants for five years to record all diagnoses of head and neck cancer, which is the sixth-leading cause of cancer-related death worldwide.
Tobacco and alcohol use increase the risk of head and neck cancers, which affect the mouth, nose, sinuses and throat.
The study found eating six servings of fruit and vegetables per day per 1,000 calories cut the risk of head and neck cancer by 29 percent compared to eating one and a half servings.
The typical adult consumes around 2,000 calories a day.
"Increasing consumption by just one serving of fruit or vegetables per 1,000 calories per day was associated with a 6 percent reduction in head and neck cancer risk, said Neal Freedman, cancer prevention fellow at the NCI.
A second study of food consumption in more than 183,000 residents of California and Hawaii found that a diet high in flavonols might help reduce pancreatic cancer risk, especially in smokers.
Flavonols are common in plant-based foods but are found in highest concentrations in onions, apples, berries, kale and broccoli.
The study found that people who ate the largest amounts of flavonols had a 23 percent reduced risk of developing pancreatic cancer compared to those who ate the least.
A Gift of Life
A Gift of Life
Bone marrow transplants can save patients suffering from diseases that were once a death sentence. But a shortage of donors has left thousands waiting for treatment.
Every year, 2,000 American lives are saved by the selflessness of others. These are the bone marrow donors who give the gift of life to patients fighting deadly diseases such as leukemia, lymphoma, and aplastic anemia. That's the good news.
The bad news is that thousands more die each year because not enough people have signed on to the registries that would help the ill find a suitable match for a transplant.
Bone marrow or stem-cell transplants are usually a last resort, intended for those whose illnesses have not responded to traditional treatments such as chemotherapy or radiation. How do they work? We all store a special type of cell in our bone marrow called stem cells. These primitive cells give rise to the three types of blood cells: red, white and platelets. Everyone's stem cells have certain genetic characteristics or markers that make them unique from others. Despite this uniqueness, there are some shared characteristics between people. This is important, because a patient's immune system will reject blood or organs received from someone else if they do not share sufficient similarities.
Family members, especially siblings, are always the first to be considered as donors, because there's a greater chance that the genetic markers on their cells will have enough in common to prevent rejection after trans? plantation. In many cases, however, a familial match can't be found and then the search begins for an unrelat? bed donor. These donors typi? cally come from a pool of people who have already signed up on a donor registry in the event that their cells match a needy recipient.
Once the lab has verified a match between donor and re?鄄cipient, the next phase starts. The patient is given radiation or chemotherapy to kill the unhealthy cells. Healthy cells are harvested from the donor - either extracted from the pelvic bones or taken from the arm in a way that is similar to having blood drawn - and prepared in a laboratory. Once they're ready, they're given to the patient through a vein - the same way as one would receive a blood transfusion. Once these transplanted donor cells get settled within the patient's bone marrow, they make the healthy red blood cells, white blood cells and platelets necessary to support life.
One of the major problems currently faced by transplant centers is that while bone-marrow transplants can cure more than 70 different diseases, there aren't enough donors on the registry to treat the more than 3,000 patients awaiting transplants. The National Marrow Donor Program, the largest registry in the country, has approximately 4.8 million adult volunteer donors, but that isn't nearly enough for the thousands who need transplants.
Why isn't a pool of more than 4 million donors isn't enough to cover 3,000 needy patients? Here's the reason: in the vast majority of cases, finding a suitable match isn't easy. Because we are unique individuals with a variety of ancestral backgrounds and integration patterns, finding someone similar to us is a major task. In the end, it comes down to a numbers game-the more potential donors listed on the registry, the greater a chance of finding a match, especially for those with unusual genetic characteristics.
Bone marrow transplants can save patients suffering from diseases that were once a death sentence. But a shortage of donors has left thousands waiting for treatment.
Every year, 2,000 American lives are saved by the selflessness of others. These are the bone marrow donors who give the gift of life to patients fighting deadly diseases such as leukemia, lymphoma, and aplastic anemia. That's the good news.
The bad news is that thousands more die each year because not enough people have signed on to the registries that would help the ill find a suitable match for a transplant.
Bone marrow or stem-cell transplants are usually a last resort, intended for those whose illnesses have not responded to traditional treatments such as chemotherapy or radiation. How do they work? We all store a special type of cell in our bone marrow called stem cells. These primitive cells give rise to the three types of blood cells: red, white and platelets. Everyone's stem cells have certain genetic characteristics or markers that make them unique from others. Despite this uniqueness, there are some shared characteristics between people. This is important, because a patient's immune system will reject blood or organs received from someone else if they do not share sufficient similarities.
Family members, especially siblings, are always the first to be considered as donors, because there's a greater chance that the genetic markers on their cells will have enough in common to prevent rejection after trans? plantation. In many cases, however, a familial match can't be found and then the search begins for an unrelat? bed donor. These donors typi? cally come from a pool of people who have already signed up on a donor registry in the event that their cells match a needy recipient.
Once the lab has verified a match between donor and re?鄄cipient, the next phase starts. The patient is given radiation or chemotherapy to kill the unhealthy cells. Healthy cells are harvested from the donor - either extracted from the pelvic bones or taken from the arm in a way that is similar to having blood drawn - and prepared in a laboratory. Once they're ready, they're given to the patient through a vein - the same way as one would receive a blood transfusion. Once these transplanted donor cells get settled within the patient's bone marrow, they make the healthy red blood cells, white blood cells and platelets necessary to support life.
One of the major problems currently faced by transplant centers is that while bone-marrow transplants can cure more than 70 different diseases, there aren't enough donors on the registry to treat the more than 3,000 patients awaiting transplants. The National Marrow Donor Program, the largest registry in the country, has approximately 4.8 million adult volunteer donors, but that isn't nearly enough for the thousands who need transplants.
Why isn't a pool of more than 4 million donors isn't enough to cover 3,000 needy patients? Here's the reason: in the vast majority of cases, finding a suitable match isn't easy. Because we are unique individuals with a variety of ancestral backgrounds and integration patterns, finding someone similar to us is a major task. In the end, it comes down to a numbers game-the more potential donors listed on the registry, the greater a chance of finding a match, especially for those with unusual genetic characteristics.
Is the health hazard from cell phones real
Is the health hazard from cell phones real
The claim: Cell phones cause brain cancer. One Swedish study published last year found a link between long-term use of the older analog cell phones and brain cancer; research in rats has shown a link between cell-phone radiation and potentially cancer-causing DNA damage.
The counterclaim: Cell phones are safe. The largest study to date, published last February in the Journal of the national Cancer Institute, surveyed 420,000 cell-phone users from 1982 and 1995 and concluded there was no evidence of a brain-cancer link. Two smaller studies, published last December in the Journal of the American medical Association and the New England Journal of Medicine, came to similar conclusions.
Expert analysis: Cancer experts feel that cell phones are safe for short-term use -- but note that more long-term research is needed. "Studies show that using cell phones for ten or fifteen years doesn't seem to increase brain cancer risk, but we don't have any research that goes beyond that," says Gansler. He points out that the analog phones in the Swedish study emit much more radiation than today's digital ones. And as for laboratory studies, " Results are much different in a test tube or a rat than they are in humans," he adds. But other experts are more cautious. "Brain tumors grow slowly and may not be detected for more than a decade," warns Henry Lai, Ph.D., professor of bioengineering at the University of Washington, in Seattle.
The bottom line: Until 20-or 30-year studies are available to demonstrate cell-phone safety, take some precautions. Start with a hands-free headset, which may minimize exposure to radiation. Keep your phone away from your body when you're not using it. Joshua Muscat, Ph.D., of the American Health Foundation in Valhalla, New York, also recommends using the newer digital phones, which have less radiation than analog. Don't use it when signal strength is poor, since that means the phone has to work harder, causing it to emit more radiation. And keep your kids off cell phones, since researchers don't know how radiation affects a developing brain. As for devices that claim to protect against radiation," There's no evidence that they work," says Muscat.
The claim: Cell phones cause brain cancer. One Swedish study published last year found a link between long-term use of the older analog cell phones and brain cancer; research in rats has shown a link between cell-phone radiation and potentially cancer-causing DNA damage.
The counterclaim: Cell phones are safe. The largest study to date, published last February in the Journal of the national Cancer Institute, surveyed 420,000 cell-phone users from 1982 and 1995 and concluded there was no evidence of a brain-cancer link. Two smaller studies, published last December in the Journal of the American medical Association and the New England Journal of Medicine, came to similar conclusions.
Expert analysis: Cancer experts feel that cell phones are safe for short-term use -- but note that more long-term research is needed. "Studies show that using cell phones for ten or fifteen years doesn't seem to increase brain cancer risk, but we don't have any research that goes beyond that," says Gansler. He points out that the analog phones in the Swedish study emit much more radiation than today's digital ones. And as for laboratory studies, " Results are much different in a test tube or a rat than they are in humans," he adds. But other experts are more cautious. "Brain tumors grow slowly and may not be detected for more than a decade," warns Henry Lai, Ph.D., professor of bioengineering at the University of Washington, in Seattle.
The bottom line: Until 20-or 30-year studies are available to demonstrate cell-phone safety, take some precautions. Start with a hands-free headset, which may minimize exposure to radiation. Keep your phone away from your body when you're not using it. Joshua Muscat, Ph.D., of the American Health Foundation in Valhalla, New York, also recommends using the newer digital phones, which have less radiation than analog. Don't use it when signal strength is poor, since that means the phone has to work harder, causing it to emit more radiation. And keep your kids off cell phones, since researchers don't know how radiation affects a developing brain. As for devices that claim to protect against radiation," There's no evidence that they work," says Muscat.
Sweet dream: Sleep less, live longer
Sweet dream: Sleep less, live longer
Contrary to popular belief, people who sleep six to seven hours a night live longer, and those who sleep eight hours or more die younger, according to the latest study ever conducted on the subject. The study, which tracked the sleeping habits of 1.1 million Americans for six years, undermines the advice of many sleep doctors who have long recommended that people get eight or nine hours of sleep every night.
"There's an old idea that people should sleep eight hours a night, which has no more scientific basis than the gold at the end of the rainbow," said Daniel Kripke, a professor of psychiatry at the University of California at San Diego who led the study, published in a recent issue of the Archives of General Psychiatry. "That's an old wives' tale."
The study was not designed to answer why sleeping longer may be deleterious or whether people could extend their life span by sleeping less.
But Kripke said it was possible that people who slept longer tended to suffer from sleep apnea, a condition where impaired breathing puts stress on the heart and brain. He also speculated that the need for sleep was akin to food, where getting less than people want may be better for them.
The study quickly provoked cautions and criticism, with some sleep experts saying that the main problem in America's sleep habits was deprivation, not sleeping too much.
"None of this says sleep kills people," said Daniel Buysse, a University of Pittsburgh psychiatrist and the immediate past president of the American Academy of Sleep Medicine.
"You should sleep as much as you need to feel awake, alert and attentive the next day," Buysse added. "I'm much more concerned about people short-changing themselves on sleep than people sleeping too long."
Sleeplessness produces a variety of health consequences that were not measured in the study, critics said.
"The amount of sleep you get impacts how alert you are, your risk for accidents, how you perform at work and school," said James Walsh, president of the National Sleep Foundation, a non-profit that advocates for better sleep habits. "There's much more to life than how long you live."
The study used data from an extensive survey conducted by the American Cancer Society from 1982 to 1988. Women sleeping 8, 9 and 10 hours a night had 13 percent, 23 percent and 41 percent higher risk of dying, respectively, than those who slept 7 hours, the study found. Men sleeping 8, 9 and 10 hours a night had 12 percent, 17 percent and 34 percent greater risk of dying within the study period.
By contrast, sleeping five hours a night increased the risk for women by only 5 percent, and for men, by 11 percent. Among people who slept just three hours a night, women had a 33 percent increase in death, and men had a 19 percent increase, compared with those who slept seven hours.
Kripke, the new study's leader, pointed out that relatively few people slept so little-1 in 1,000 - where as almost half of all people slept eight hours or more.
The study also found that taking a sleeping pill every day increased the risk of death by 25 percent.
"It appears there is no mortality risk to having insomnia," Kripke said.
He recommended that people should not routinely take pills to get eight hours of sleep. While acknowledging that the sleeping pills used from 1982 to 1988 were not the same pills being used today, Kripke said, "without data showing that contemporary pills are safe, these data provide the best information about whether sleeping pills are safe for long-term use."
Kripke, whose study was funded by federal tax dollars, said doctors' recommendations that everyone get eight hours of sleep a night may have been partly influenced by the drug companies that make sleeping pills. He cited a report from a public relations firm representing the medicine Ambien, which gave money to the National Sleep Foundation to alert people about an insomnia "public health crisis" as part of a marketing campaign.
Both Buysse and Walsh have served as paid consultants to makers of sleeping pills, but both denied being influenced by that role. Walsh said most researchers in the field had accepted consulting fees from the companies, because "99 percent of the funding to support this type of research is from pharmaceutical companies."
Buysse, who wrote an editorial accompanying Kripke's article, said more research was needed to pin down exactly what the connection was between sleep and the risk of death. The study relied on people's own reports of their sleeping habits, which can be faulty. When people are asked how long they sleep, they usually report how long they spend in bed, Buysse said.
That could mean that people who reported sleeping eight hours were really sleeping around seven and a half hours, which would bring them into the study's lower risk category. Buysse also disagreed that sleep was like food, arguing that while people can restrict sleep, they cannot "choose" to sleep longer.
Donald Bliwise, a psychologist at Emory University, in Atlanta, said studies had shown that when people were allowed to sleep however long they wanted, without cues from alarm clocks and watches, they often slept 14 to 15 hours a day for the first few days.
"Everyone," Bliwise said, "walks around somewhat sleep deprived."
International Herald Tribunal
Contrary to popular belief, people who sleep six to seven hours a night live longer, and those who sleep eight hours or more die younger, according to the latest study ever conducted on the subject. The study, which tracked the sleeping habits of 1.1 million Americans for six years, undermines the advice of many sleep doctors who have long recommended that people get eight or nine hours of sleep every night.
"There's an old idea that people should sleep eight hours a night, which has no more scientific basis than the gold at the end of the rainbow," said Daniel Kripke, a professor of psychiatry at the University of California at San Diego who led the study, published in a recent issue of the Archives of General Psychiatry. "That's an old wives' tale."
The study was not designed to answer why sleeping longer may be deleterious or whether people could extend their life span by sleeping less.
But Kripke said it was possible that people who slept longer tended to suffer from sleep apnea, a condition where impaired breathing puts stress on the heart and brain. He also speculated that the need for sleep was akin to food, where getting less than people want may be better for them.
The study quickly provoked cautions and criticism, with some sleep experts saying that the main problem in America's sleep habits was deprivation, not sleeping too much.
"None of this says sleep kills people," said Daniel Buysse, a University of Pittsburgh psychiatrist and the immediate past president of the American Academy of Sleep Medicine.
"You should sleep as much as you need to feel awake, alert and attentive the next day," Buysse added. "I'm much more concerned about people short-changing themselves on sleep than people sleeping too long."
Sleeplessness produces a variety of health consequences that were not measured in the study, critics said.
"The amount of sleep you get impacts how alert you are, your risk for accidents, how you perform at work and school," said James Walsh, president of the National Sleep Foundation, a non-profit that advocates for better sleep habits. "There's much more to life than how long you live."
The study used data from an extensive survey conducted by the American Cancer Society from 1982 to 1988. Women sleeping 8, 9 and 10 hours a night had 13 percent, 23 percent and 41 percent higher risk of dying, respectively, than those who slept 7 hours, the study found. Men sleeping 8, 9 and 10 hours a night had 12 percent, 17 percent and 34 percent greater risk of dying within the study period.
By contrast, sleeping five hours a night increased the risk for women by only 5 percent, and for men, by 11 percent. Among people who slept just three hours a night, women had a 33 percent increase in death, and men had a 19 percent increase, compared with those who slept seven hours.
Kripke, the new study's leader, pointed out that relatively few people slept so little-1 in 1,000 - where as almost half of all people slept eight hours or more.
The study also found that taking a sleeping pill every day increased the risk of death by 25 percent.
"It appears there is no mortality risk to having insomnia," Kripke said.
He recommended that people should not routinely take pills to get eight hours of sleep. While acknowledging that the sleeping pills used from 1982 to 1988 were not the same pills being used today, Kripke said, "without data showing that contemporary pills are safe, these data provide the best information about whether sleeping pills are safe for long-term use."
Kripke, whose study was funded by federal tax dollars, said doctors' recommendations that everyone get eight hours of sleep a night may have been partly influenced by the drug companies that make sleeping pills. He cited a report from a public relations firm representing the medicine Ambien, which gave money to the National Sleep Foundation to alert people about an insomnia "public health crisis" as part of a marketing campaign.
Both Buysse and Walsh have served as paid consultants to makers of sleeping pills, but both denied being influenced by that role. Walsh said most researchers in the field had accepted consulting fees from the companies, because "99 percent of the funding to support this type of research is from pharmaceutical companies."
Buysse, who wrote an editorial accompanying Kripke's article, said more research was needed to pin down exactly what the connection was between sleep and the risk of death. The study relied on people's own reports of their sleeping habits, which can be faulty. When people are asked how long they sleep, they usually report how long they spend in bed, Buysse said.
That could mean that people who reported sleeping eight hours were really sleeping around seven and a half hours, which would bring them into the study's lower risk category. Buysse also disagreed that sleep was like food, arguing that while people can restrict sleep, they cannot "choose" to sleep longer.
Donald Bliwise, a psychologist at Emory University, in Atlanta, said studies had shown that when people were allowed to sleep however long they wanted, without cues from alarm clocks and watches, they often slept 14 to 15 hours a day for the first few days.
"Everyone," Bliwise said, "walks around somewhat sleep deprived."
International Herald Tribunal
Are These the Best Years of Your Life?
Are These the Best Years of Your Life?
The ups and downs of life may seem to have no predictable plan.But scientists now know there are very definite patterns that almost all people share.Even if you’ve passed some of your “prime”,you still have other prime years to experience in the future.Certain important primes seem to peak later in life.
When are you smartest?From 18—25,according to I.Q.scores;but you’re wiser and more experienced with increasing age.
You’re sharpest in your 20’s;around 30,memory begins to decline,particularly your ability to perform mathematical computations.But your I.Q.for other tasks climbs.Your vocabulary at age 45,for example is three times as great as when you graduated from college.At 60,your brain possesses almost four times as much information as it did at age 21.This trade-off between sharpness and wisdom has led psychologists to suggest that “maturity quotients”(M.Q.)be adopted for adults.
When are you happiest?You have the best physical sense of yourself from 15to 24;the best professional sense from 40to 49.
Before age 24,we believe that our happiest years are yet to come;over30,we believe that they’re behind us.A National Health Survey agrees:After age 30,we “become more realistic and do not view happiness as a goal in itself.If we maintain our health,achieve professional and emotional goals,then happiness,we feel,will follow”.
When are you most creative?Generally between 30and 39,but the peak varies with different professions.
Mozart wrote a symphony and four sonatas by age eight,and Mendelssohn composed his best known work A Midsummer Night’s Dream,at 17,but most of the great music was written by men between 33and 39.Though the peak in most fields comes early——most Nobel prize winners did their top research in their late 20’s and 30’s——creative people continue to produce quality work throughout their lives.For the “well-conditioned mind”,there is no upper limit.
The ups and downs of life may seem to have no predictable plan.But scientists now know there are very definite patterns that almost all people share.Even if you’ve passed some of your “prime”,you still have other prime years to experience in the future.Certain important primes seem to peak later in life.
When are you smartest?From 18—25,according to I.Q.scores;but you’re wiser and more experienced with increasing age.
You’re sharpest in your 20’s;around 30,memory begins to decline,particularly your ability to perform mathematical computations.But your I.Q.for other tasks climbs.Your vocabulary at age 45,for example is three times as great as when you graduated from college.At 60,your brain possesses almost four times as much information as it did at age 21.This trade-off between sharpness and wisdom has led psychologists to suggest that “maturity quotients”(M.Q.)be adopted for adults.
When are you happiest?You have the best physical sense of yourself from 15to 24;the best professional sense from 40to 49.
Before age 24,we believe that our happiest years are yet to come;over30,we believe that they’re behind us.A National Health Survey agrees:After age 30,we “become more realistic and do not view happiness as a goal in itself.If we maintain our health,achieve professional and emotional goals,then happiness,we feel,will follow”.
When are you most creative?Generally between 30and 39,but the peak varies with different professions.
Mozart wrote a symphony and four sonatas by age eight,and Mendelssohn composed his best known work A Midsummer Night’s Dream,at 17,but most of the great music was written by men between 33and 39.Though the peak in most fields comes early——most Nobel prize winners did their top research in their late 20’s and 30’s——creative people continue to produce quality work throughout their lives.For the “well-conditioned mind”,there is no upper limit.
Stay thin by sleeping more? (Image)
Stay thin by sleeping more?
A study published Monday found that people who sleep less tend to be fat, and experts said it's time find if more sleep will fight obesity.
"We've put so much emphasis on diet and exercise that we've failed to recognize the value of good sleep," said Fred Turek, a physician at Northwestern University.
Monday's study from Eastern Virginia Medical School in Norfolk covered 1,000 people and found that total sleep time decreased as body mass index -- a measure of weight based on height -- increased.
Men slept an average of 27 minutes less than women and overweight and obese patients slept less than patients with normal weights, it said. In general the fatter subjects slept about 1.8 hours a week less than those with normal weights.
"Americans experience insufficient sleep and corpulent bodies. Clinicians are aware of the burden of obesity on patients," the study said.
"Our findings suggest that major extensions of sleep time may not be necessary, as an extra 20 minutes of sleep per night seems to be associated with a lower body mass index," it added.
"We caution that this study does not establish a cause-and-effect relationship between restricted sleep and obesity (but) investigations demonstrating success in weight loss via extensions of sleep would help greatly to establish such a relationship."
The study was published in the Archives of Internal Medicine along with an editorial by Turek and Northwestern colleague Joseph Bass commenting on it and related research.
In an interview with Reuters, Turek said some studies have shown sleep deprivation causes declines in an appetite suppressing protein hormone called leptin, and increases in another hormone that causes a craving for food. In addition neuropeptides in the brain governing sleep and obesity appear to overlap, he said.
Obesity has been rising dramatically in developed countries and reached epidemic levels in the United States, it added, leading to a variety of health problems.
obese: extremely fat; grossly overweight.
corpulent : excessively fat.
clinician: a physician, psychologist, or psychiatrist specializing in clinical studies or practice.
leptin.
U.S. re-transmission speed up the fight against AIDS situation grim
U.S. re-transmission speed up the fight against AIDS situation grim
The United States is losing ground again in its fight against AIDS with blacks, particularly African-American women, suffering most from the resurgent spread of the virus.
Health experts blame a lack of education resources while American adults are showing growing complacency to the risks they run.
The number of cases of Acquired Immune Deficiency Syndrome (AIDS) fell by 50 percent from 1993 to 2001 before rising two percent in 2002, according to figures from the Centers for Disease Control and Prevention (CDC), which releases its latest figures Wednesday.
The number of deaths hit an annual peak of 52,000 in 1995 before seeing major falls with the advent of new medications. Those falls continued through 2001, but the following year saw a rise to 16,371 AIDS deaths, according to the CDC.
More than 500,000 people are now believed to have died from AIDS in the United States, with almost 900,000 estimated to be infected with the virus.
"It's a pretty bad situation," said Sherry Kaplan, coordinator for the Center for Positive Connection in Miami, a private help centre in one of the worst-hit regions of the United States.
"It's a tragedy that there is no wake-up call, that we have our own epidemic going on here in the US and the money isn't coming in, that there is no proper education prevention," added Kaplan, who has been HIV positive for 17 years.
Kaplan said that people now show "a more casual attitude" to sex because they believe medication will help them with AIDS.
The United States is losing ground again in its fight against AIDS with blacks, particularly African-American women, suffering most from the resurgent spread of the virus.
Health experts blame a lack of education resources while American adults are showing growing complacency to the risks they run.
The number of cases of Acquired Immune Deficiency Syndrome (AIDS) fell by 50 percent from 1993 to 2001 before rising two percent in 2002, according to figures from the Centers for Disease Control and Prevention (CDC), which releases its latest figures Wednesday.
The number of deaths hit an annual peak of 52,000 in 1995 before seeing major falls with the advent of new medications. Those falls continued through 2001, but the following year saw a rise to 16,371 AIDS deaths, according to the CDC.
More than 500,000 people are now believed to have died from AIDS in the United States, with almost 900,000 estimated to be infected with the virus.
"It's a pretty bad situation," said Sherry Kaplan, coordinator for the Center for Positive Connection in Miami, a private help centre in one of the worst-hit regions of the United States.
"It's a tragedy that there is no wake-up call, that we have our own epidemic going on here in the US and the money isn't coming in, that there is no proper education prevention," added Kaplan, who has been HIV positive for 17 years.
Kaplan said that people now show "a more casual attitude" to sex because they believe medication will help them with AIDS.
Health Fears for Obese Children
Around half a million children in Europe are suffering classic health problems of the middle-aged because they are too fat, according to new estimates.
The levels of obesity among Europe's children have been on the rise over the last 15 years, but experts are now starting to see the health consequences emerge on a large scale.
In Britain, one in five children is overweight or obese. In Spain the figure rises to 30% of children, and in Italy it reaches 36%. According to US government estimates, 30% of American children are overweight or obese.
In a new analysis presented at the start of this year's European Congress on Obesity in Athens, experts reported that high blood pressure, raised cholesterol, damaged blood sugar regulation and other dangerous conditions -- often referred to collectively as the metabolic syndrome -- were increasingly being identified alongside the rising levels of childhood obesity in Europe.
"The figures suggest that children in the EU could soon be measuring up to their counterparts in the US, where the numbers affected by the metabolic syndrome doubled from 910,000 to two million in less than 10 years," said the analysis by the International Obesity Task Force, a network of eminent obesity scientists and policy experts.
The group estimated that between 2,000 and 10,000 European children already had the type of diabetes usually diagnosed in middle age.
As the estimates were unveiled, a statement was delivered to the conference on behalf of EU Commissioner for Health and Consumer Protection Markos Kyprianou.
He outlined plans for a Europewide code of conduct to rein in the marketing of unhealthy food to children and broader policy initiatives across agriculture, education and transport that address the obesity problem.
The European Union would publish a new strategy on diet and exercise before the end of the year and submit the document to public consultation with the food industry, anti-obesity activists and others to shape a final plan by the end of 2006, Mr Kyprianou said.
The move echoes unprecedented steps taken last year by the World Health Organisation, which launched a global strategy on diet and physical activity after health ministers from around the world approved the plan.
The levels of obesity among Europe's children have been on the rise over the last 15 years, but experts are now starting to see the health consequences emerge on a large scale.
In Britain, one in five children is overweight or obese. In Spain the figure rises to 30% of children, and in Italy it reaches 36%. According to US government estimates, 30% of American children are overweight or obese.
In a new analysis presented at the start of this year's European Congress on Obesity in Athens, experts reported that high blood pressure, raised cholesterol, damaged blood sugar regulation and other dangerous conditions -- often referred to collectively as the metabolic syndrome -- were increasingly being identified alongside the rising levels of childhood obesity in Europe.
"The figures suggest that children in the EU could soon be measuring up to their counterparts in the US, where the numbers affected by the metabolic syndrome doubled from 910,000 to two million in less than 10 years," said the analysis by the International Obesity Task Force, a network of eminent obesity scientists and policy experts.
The group estimated that between 2,000 and 10,000 European children already had the type of diabetes usually diagnosed in middle age.
As the estimates were unveiled, a statement was delivered to the conference on behalf of EU Commissioner for Health and Consumer Protection Markos Kyprianou.
He outlined plans for a Europewide code of conduct to rein in the marketing of unhealthy food to children and broader policy initiatives across agriculture, education and transport that address the obesity problem.
The European Union would publish a new strategy on diet and exercise before the end of the year and submit the document to public consultation with the food industry, anti-obesity activists and others to shape a final plan by the end of 2006, Mr Kyprianou said.
The move echoes unprecedented steps taken last year by the World Health Organisation, which launched a global strategy on diet and physical activity after health ministers from around the world approved the plan.
New Key to Obesity
New Key to Obesity
The discovery of the obesity gene in humans half a decade ago offered evidence that chronic weight gain is the consequence of a mismatch between nature and nurture. Simplistic explanations, such as blaming obesity on a drop in fat consumption, ignore scientific reality. In countries like India and China, obesity was virtually unknown until the introduction of a high-fat, Western-style diet.
One well-known reason for this is that dietary fat converts to body fat more effciently than does protein or carbohydrate, but recently scientists have uncovered what appears to be an equally important factor. Some researchers in universities are investigating the possibility that high levels of fat and fructose are mucking up our brain chemistry, and thereby muting the signals that would normally tell us to put down the fork. These signals are produced by peptides, which are regulated by a number of hormones. Under normal conditions these hormones help maintain a stable body weight by adjusting levels of the peptides that control eating. But a diet loaded with fat and fructose hampers the regulation of these hormones. Complicating matters still further is that the brain loses its ability to respond to these hormones as body fat increases -- so the obese are doubly penalized.
Other researchers are finding evidence that constant exposure to fat and sugar can cause some humans to crave them as they do an addictive drug. A Princeton University psychologist recently showed that rats fed a high sugar diet were, when the sugar was removed, thrown into a state of anxiety similar to that seen in withdrawal from morphine or nicotine. Sarah Leibowitz, a neurobiologist, believes that frequent exposure to fatty foods may configure the brain to crave still more fat. She has shown in animal studies that galanin, a brain peptide that simulates eating behavior and decreases energy expenditure, increases when the animal eats a high-fat diet.
There are many factors contributing to the explosion of obesity in the United States, and the world, but the radical changes in the composition of our diet are first among them. While scientific work in this arena is in its infancy, it's already clear that varying the amount of fat and other nutrients in the diet affects brain chemistry by activating certain genes, and this in turn directs our dietary preferences. By submitting ourselves to a steady dose of highly processed, sweet, high-fat foods, we have unwittingly entered into a dangerous experiment, the long term consequences of which are only now beginning to surface.
The discovery of the obesity gene in humans half a decade ago offered evidence that chronic weight gain is the consequence of a mismatch between nature and nurture. Simplistic explanations, such as blaming obesity on a drop in fat consumption, ignore scientific reality. In countries like India and China, obesity was virtually unknown until the introduction of a high-fat, Western-style diet.
One well-known reason for this is that dietary fat converts to body fat more effciently than does protein or carbohydrate, but recently scientists have uncovered what appears to be an equally important factor. Some researchers in universities are investigating the possibility that high levels of fat and fructose are mucking up our brain chemistry, and thereby muting the signals that would normally tell us to put down the fork. These signals are produced by peptides, which are regulated by a number of hormones. Under normal conditions these hormones help maintain a stable body weight by adjusting levels of the peptides that control eating. But a diet loaded with fat and fructose hampers the regulation of these hormones. Complicating matters still further is that the brain loses its ability to respond to these hormones as body fat increases -- so the obese are doubly penalized.
Other researchers are finding evidence that constant exposure to fat and sugar can cause some humans to crave them as they do an addictive drug. A Princeton University psychologist recently showed that rats fed a high sugar diet were, when the sugar was removed, thrown into a state of anxiety similar to that seen in withdrawal from morphine or nicotine. Sarah Leibowitz, a neurobiologist, believes that frequent exposure to fatty foods may configure the brain to crave still more fat. She has shown in animal studies that galanin, a brain peptide that simulates eating behavior and decreases energy expenditure, increases when the animal eats a high-fat diet.
There are many factors contributing to the explosion of obesity in the United States, and the world, but the radical changes in the composition of our diet are first among them. While scientific work in this arena is in its infancy, it's already clear that varying the amount of fat and other nutrients in the diet affects brain chemistry by activating certain genes, and this in turn directs our dietary preferences. By submitting ourselves to a steady dose of highly processed, sweet, high-fat foods, we have unwittingly entered into a dangerous experiment, the long term consequences of which are only now beginning to surface.
Estrogen, Dangerous
Estrogen, Dangerous
Women had been told for decades that estrogen taken with progestin would not only ease hot flashes and insomnia but help preserve bone strength，mental acuity and，most important，heart health. There's no question that HRT can ease the acute symptoms of menopause，and the claim about bone strength had held up to scrutiny. But after observing more than 16,000 women for roughly five years，researchers found conclusively that hormones raise the risk of heart attack，stroke，blood clots and breast cancer.
The announcement caused a near panic among the more than 13 million American women now on hormone-replacement therapy. Fortunately，the study didn't uncover huge，unimagined dangers to patients. But for millions of women juggling the pros and cons of long-term HRT，the new findings offer something virtually unprecedented，which is clarity. Even a small risk to individuals can have big consequences when applied to a large population.
The study suggests that，on balance，a group of 10,000 long-term estrogen users would suffer 31 excess health crises each year（strokes，heart attacks，blood clots，breast cancers），while avoiding only 11 bone fractures and colon cancers. That's a net increase of20. If 100,000 people take up long-term HRT，they'll suffer 200 of these needless events each year. A million long-term estrogen users will experience 20,000 of them annually--which means20,000 over the course of a decade. This is no way to prevent hip fractures.
Short-term use is a different story. The study didn't turn up unacceptable risks among womentreated for less than five years，and experts agree there is still no better treatment for the hot flashes，mood swings and insomnia that many women experience around the time of menopause.
Women had been told for decades that estrogen taken with progestin would not only ease hot flashes and insomnia but help preserve bone strength，mental acuity and，most important，heart health. There's no question that HRT can ease the acute symptoms of menopause，and the claim about bone strength had held up to scrutiny. But after observing more than 16,000 women for roughly five years，researchers found conclusively that hormones raise the risk of heart attack，stroke，blood clots and breast cancer.
The announcement caused a near panic among the more than 13 million American women now on hormone-replacement therapy. Fortunately，the study didn't uncover huge，unimagined dangers to patients. But for millions of women juggling the pros and cons of long-term HRT，the new findings offer something virtually unprecedented，which is clarity. Even a small risk to individuals can have big consequences when applied to a large population.
The study suggests that，on balance，a group of 10,000 long-term estrogen users would suffer 31 excess health crises each year（strokes，heart attacks，blood clots，breast cancers），while avoiding only 11 bone fractures and colon cancers. That's a net increase of20. If 100,000 people take up long-term HRT，they'll suffer 200 of these needless events each year. A million long-term estrogen users will experience 20,000 of them annually--which means20,000 over the course of a decade. This is no way to prevent hip fractures.
Short-term use is a different story. The study didn't turn up unacceptable risks among womentreated for less than five years，and experts agree there is still no better treatment for the hot flashes，mood swings and insomnia that many women experience around the time of menopause.
Breast cancer patients turning to alternative care
Breast cancer patients turning to alternative care
Growing majority combine holistic therapies with traditional medicine.
Six months of chemotherapy for breast cancer weighed heavily on Karen Lehman. "I felt crummy," says the normally cheerful 49-year-old. "There was the fatigue and the constant queasiness." To help cope, she tried acupuncture and craniosacral massage and is considering other alternative therapies as she continues battling cancer.
HER HOLISTIC APPROACH is not unusual. In fact, Lehman is one of a growing majority of breast cancer patients who are turning to alternative therapies to help deal with the side effects of conventional treatment or compensate for the times when mainstream medicine falls short.
As many as 70 percent of cancer patients use alternative therapies, including dietary supplements, acupuncture, hypnotism, massage, guided imagery, magnets and biofeedback, according to a recent report in The Journal of Alternative and Complementary Medicine. The study, a telephone survey of more than 350 cancer patients in Washington State, found that breast cancer patients were the group most likely to try holistic approaches and that almost all respondents believed the treatments improved their well-being. Other studies have also shown that alternative medicine use is common among people with life-threatening illnesses.
"I expected there to be a high percentage of cancer patients using alternative therapies because I think these patients are looking for ways to help their health and to take control of their health care," says study author Ruth Patterson, a scientist at the Fred Hutchinson Cancer Research Center in Seattle. "The unexpected piece of this is just how high the satisfaction level was. Patients felt these things helped them feel better - that's nothing to sneeze at."
Alternative practitioners, who emphasize mind/body wellness, can be a welcome change to patients frustrated with hurried doctors who don't always have the answers - or who give conflicting advice on key issues like mammograms and breast self-exams.
INDIVIDUALIZED APPROACH
"People feel that alternative medicine is more tuned into their bodies, rather than a one-size-fits-all approach that tends to be common in Western medicine," says Dr. Debu Tripathy, director of the breast cancer research program at the University of Texas Southwestern Medical Center at Dallas and co-editor of the new book "Breast Cancer: Beyond Convention".
But the new survey findings raise questions that are at the heart of the ongoing debate over alternative therapies. Do they actually fight disease? Or is the effect just psychological? Or a combination of both? When it comes to breast cancer, as with many diseases, there are few clear answers.
Supplements are one of the most popular alternative therapies for breast cancer, but experts say there is no convincing evidence to support their use. "Most of what is sold to treat or cure cancer are concoctions that people put together," says Barrie Cassileth, chief of the integrative medicine service at Memorial Sloan-Kettering Cancer Center in New York. "They should be looked at with a jaundiced eye."
SUPPLEMENT DANGERS
What's more, certain supplements may be dangerous. "Herbs can interfere with the amount of medicine that can get into the body and can also interfere with the coagulation of blood, which can be a problem with surgery," Cassileth warns. For instance, St. John's wort and various antioxidants, including vitamins C and E, may reduce the effectiveness of standard treatments like chemotherapy. And experts say that although soy in the diet may offer some protection against breast cancer, high-dose soy supplements or other products containing plant estrogens may, paradoxically, have the opposite effect - fueling the growth of tumors - in women with the disease.
Another concern is that a supplement may not contain what the label claims or may be contaminated with harmful substances, says Leanna Standish, a naturopathic doctor at Bastyr University in Kenmore, Wash. Supplements are not subject to the same strict safety and effectiveness standards as dru gs. Because of this, Standish generally advises patients to avoid over-the-counter supplements.
In some cases, though, supplements prescribed by a qualified naturopath or herbalist may be used safely as an adjunct to standard care, she maintains. Standish receives many referrals from oncologists whose patients are interested in trying alternatives. Though not definitively proven to work, she often prescribes coenzyme Q10, vitamins E and B6, quercetin and garlic because laboratory studies have suggested they may be beneficial. Standish is tracking her patients to see if the supplements actually work. But she cautions patients against rushing to take these supplements on their own, since they may cause problems depending on the dose and other treatments used.
Tripathy also is studying herbs to see if they can help with the side effects of chemotherapy or as actual cancer fighters. One of his studies is testing whether herbs such as skullcap, which showed promise in the lab, can help shrink breast tumors in patients with advanced disease who cannot be cured by conventional medicine.
While the jury remains out on supplements for breast cancer, some alternative therapies are gaining acceptance as potentially beneficial modalities when used in conjunction with standard care. Such "complementary" approaches as massage therapy, meditation and yoga may boost patients' mood and well-being, experts say. "Some of the mind/body techniques can certainly help the emotional state and that's a valuable thing," says Tripathy. "The question is, Can they help the cancer itself?"
Lehman has had mixed results with the alternative approaches she's tried. Though acupuncture has been shown to fight chemotherapy-induced nausea, she doesn't think her 10-week treatment helped all that much. "I had one week where it was wow - I was symptom-free - but it went downhill after that," says Lehmane . (the end) Newsweek.
Growing majority combine holistic therapies with traditional medicine.
Six months of chemotherapy for breast cancer weighed heavily on Karen Lehman. "I felt crummy," says the normally cheerful 49-year-old. "There was the fatigue and the constant queasiness." To help cope, she tried acupuncture and craniosacral massage and is considering other alternative therapies as she continues battling cancer.
HER HOLISTIC APPROACH is not unusual. In fact, Lehman is one of a growing majority of breast cancer patients who are turning to alternative therapies to help deal with the side effects of conventional treatment or compensate for the times when mainstream medicine falls short.
As many as 70 percent of cancer patients use alternative therapies, including dietary supplements, acupuncture, hypnotism, massage, guided imagery, magnets and biofeedback, according to a recent report in The Journal of Alternative and Complementary Medicine. The study, a telephone survey of more than 350 cancer patients in Washington State, found that breast cancer patients were the group most likely to try holistic approaches and that almost all respondents believed the treatments improved their well-being. Other studies have also shown that alternative medicine use is common among people with life-threatening illnesses.
"I expected there to be a high percentage of cancer patients using alternative therapies because I think these patients are looking for ways to help their health and to take control of their health care," says study author Ruth Patterson, a scientist at the Fred Hutchinson Cancer Research Center in Seattle. "The unexpected piece of this is just how high the satisfaction level was. Patients felt these things helped them feel better - that's nothing to sneeze at."
Alternative practitioners, who emphasize mind/body wellness, can be a welcome change to patients frustrated with hurried doctors who don't always have the answers - or who give conflicting advice on key issues like mammograms and breast self-exams.
INDIVIDUALIZED APPROACH
"People feel that alternative medicine is more tuned into their bodies, rather than a one-size-fits-all approach that tends to be common in Western medicine," says Dr. Debu Tripathy, director of the breast cancer research program at the University of Texas Southwestern Medical Center at Dallas and co-editor of the new book "Breast Cancer: Beyond Convention".
But the new survey findings raise questions that are at the heart of the ongoing debate over alternative therapies. Do they actually fight disease? Or is the effect just psychological? Or a combination of both? When it comes to breast cancer, as with many diseases, there are few clear answers.
Supplements are one of the most popular alternative therapies for breast cancer, but experts say there is no convincing evidence to support their use. "Most of what is sold to treat or cure cancer are concoctions that people put together," says Barrie Cassileth, chief of the integrative medicine service at Memorial Sloan-Kettering Cancer Center in New York. "They should be looked at with a jaundiced eye."
SUPPLEMENT DANGERS
What's more, certain supplements may be dangerous. "Herbs can interfere with the amount of medicine that can get into the body and can also interfere with the coagulation of blood, which can be a problem with surgery," Cassileth warns. For instance, St. John's wort and various antioxidants, including vitamins C and E, may reduce the effectiveness of standard treatments like chemotherapy. And experts say that although soy in the diet may offer some protection against breast cancer, high-dose soy supplements or other products containing plant estrogens may, paradoxically, have the opposite effect - fueling the growth of tumors - in women with the disease.
Another concern is that a supplement may not contain what the label claims or may be contaminated with harmful substances, says Leanna Standish, a naturopathic doctor at Bastyr University in Kenmore, Wash. Supplements are not subject to the same strict safety and effectiveness standards as dru gs. Because of this, Standish generally advises patients to avoid over-the-counter supplements.
In some cases, though, supplements prescribed by a qualified naturopath or herbalist may be used safely as an adjunct to standard care, she maintains. Standish receives many referrals from oncologists whose patients are interested in trying alternatives. Though not definitively proven to work, she often prescribes coenzyme Q10, vitamins E and B6, quercetin and garlic because laboratory studies have suggested they may be beneficial. Standish is tracking her patients to see if the supplements actually work. But she cautions patients against rushing to take these supplements on their own, since they may cause problems depending on the dose and other treatments used.
Tripathy also is studying herbs to see if they can help with the side effects of chemotherapy or as actual cancer fighters. One of his studies is testing whether herbs such as skullcap, which showed promise in the lab, can help shrink breast tumors in patients with advanced disease who cannot be cured by conventional medicine.
While the jury remains out on supplements for breast cancer, some alternative therapies are gaining acceptance as potentially beneficial modalities when used in conjunction with standard care. Such "complementary" approaches as massage therapy, meditation and yoga may boost patients' mood and well-being, experts say. "Some of the mind/body techniques can certainly help the emotional state and that's a valuable thing," says Tripathy. "The question is, Can they help the cancer itself?"
Lehman has had mixed results with the alternative approaches she's tried. Though acupuncture has been shown to fight chemotherapy-induced nausea, she doesn't think her 10-week treatment helped all that much. "I had one week where it was wow - I was symptom-free - but it went downhill after that," says Lehmane . (the end) Newsweek.
Weight Epidemic
Weight Epidemic
Citing an epidemic of obesity, Surgeon General Dr. David Satcher today called on communities and schools to help children and adults lose weight and stay healthy.
Satcher identified schools as central to efforts to prevent and decrease excess weight problems, and recommended they improve physical education programs and provide healthy food alternatives. Communities also must offer safe places to exercise, he urged.
Satcher identified schools as central to efforts to prevent and decrease excess weight problems, and recommended they improve physical education programs and provide healthy food alternatives. Communities also must offer safe places to exercise, he urged.
"Many people believe that dealing with overweight and obesity is a personal responsibility," Satcher states. "To some degree they are right, but it is also a community responsibility."
An estimated 300,000 deaths may be attributed to obesity in the United States each year, and more than 60 percent of adults in 1999 could be classified as overweight or obese, according to the new report from the surgeon general.
An estimated 300,000 deaths may be attributed to obesity in the United States each year, and more than 60 percent of adults in 1999 could be classified as overweight or obese, according to the new report from the surgeon general.
But the problem is not just a concern for adults. The prevalence of obesity for adolescents has nearly tripled in the past two decades, making early intervention all the more critical.
According to the report, in 1999, 13 percent of children between the ages of 6 and 11 and 14 percent of those aged 12 to 19 were overweight.
According to the report, in 1999, 13 percent of children between the ages of 6 and 11 and 14 percent of those aged 12 to 19 were overweight.
And the younger a person begins to carry excess weight, the greater the potential impact on their future quality of life. Weight gain and obesity are major contributors to poor health, increasing the risk of a number of medical conditions including heart disease, diabetes, arthritis, asthma, and even certain cancers.
British Scientists Eye Breakthrough in Lab-grown Liver
British Scientists Eye Breakthrough in Lab-grown Liver
LONDON (AFP) - Scientists at an English university have grown a miniature artificial human liver in a major medical breakthrough.
It is hoped mini-livers could be used to test drugs, reducing the need for animal experiments, help repair damaged livers and eventually produce entire organs for lifesaving transplants, the Daily Mail newspaper reported.
The organ, which is about the size of a thumbnail, was grown using stemcells in blood taken from umbilical cords.
Professor Colin McGuckin, who specializes in regenerative medicine, made the breakthrough with Doctor Nico Forraz at Newcastle University in northeast England.
While other scientists have created liver cells, the Newcastle team are the first to create sizeable sections of tissue from stem cells from the umbilical cord, the Daily Mail said.
The pair extracted blood from the umbilical cords of newborn babies. They were then placed in a "bioreactor" developed by NASA, which mimics the effects of weightlessness. This allows the cells to multiply more quickly.
Chemicals and hormones are then added to encourage the stem cells to turn into liver tissue.
"We take the stem cells from the umbilical cord blood and make small mini-livers," said McGuckin. "We then give them to pharmaceutical companies and they can use them to test new drugs on.
"When a drug company is developing a new drug it first tests it on human cells and then tests it on animals before beginning trials on humans," he said.
And he added: "Moving from testing on animals to humans is a massive leap and there is still a risk. But by using the mini-livers we have developed there is no need to test on animals or humans."
They could potentially be used like dialysis machines, buying time for a patient's liver to repair itself or for doctors to find a replacement liver.
Professor Ian Gilmore, a liver specialist at the Royal Liverpool Hospital in northwest England, told the BBC that the Newcastle team had made a "big ethical leap forward" in not requiring embryos to produce tissue.
"It is exciting because there is a real dearth of treatments available for people with liver disease," he said.
It is estimated that up to 10 percent of the British population have liver problems, mostly linked to lifestyle factors such as obesity and alcoholism, the BBC said.
LONDON (AFP) - Scientists at an English university have grown a miniature artificial human liver in a major medical breakthrough.
It is hoped mini-livers could be used to test drugs, reducing the need for animal experiments, help repair damaged livers and eventually produce entire organs for lifesaving transplants, the Daily Mail newspaper reported.
The organ, which is about the size of a thumbnail, was grown using stemcells in blood taken from umbilical cords.
Professor Colin McGuckin, who specializes in regenerative medicine, made the breakthrough with Doctor Nico Forraz at Newcastle University in northeast England.
While other scientists have created liver cells, the Newcastle team are the first to create sizeable sections of tissue from stem cells from the umbilical cord, the Daily Mail said.
The pair extracted blood from the umbilical cords of newborn babies. They were then placed in a "bioreactor" developed by NASA, which mimics the effects of weightlessness. This allows the cells to multiply more quickly.
Chemicals and hormones are then added to encourage the stem cells to turn into liver tissue.
"We take the stem cells from the umbilical cord blood and make small mini-livers," said McGuckin. "We then give them to pharmaceutical companies and they can use them to test new drugs on.
"When a drug company is developing a new drug it first tests it on human cells and then tests it on animals before beginning trials on humans," he said.
And he added: "Moving from testing on animals to humans is a massive leap and there is still a risk. But by using the mini-livers we have developed there is no need to test on animals or humans."
They could potentially be used like dialysis machines, buying time for a patient's liver to repair itself or for doctors to find a replacement liver.
Professor Ian Gilmore, a liver specialist at the Royal Liverpool Hospital in northwest England, told the BBC that the Newcastle team had made a "big ethical leap forward" in not requiring embryos to produce tissue.
"It is exciting because there is a real dearth of treatments available for people with liver disease," he said.
It is estimated that up to 10 percent of the British population have liver problems, mostly linked to lifestyle factors such as obesity and alcoholism, the BBC said.
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