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We give you many useful information about health

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We give you many useful information about health

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Sabtu, 29 Oktober 2011

When breast cancer tests get it wrong

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AppId is over the quota
Kathleen Maxian says her cancer could have been prevented, and now she's angry. Kathleen Maxian says her cancer could have been prevented, and now she's angry. Myriad Genetics owns the patent on breast cancer genesMyriad offers one test that catches most abnormalities, then charges $700 for secondCompany defends BART test, based on separate technology

(CNN) -- Imagine going in for a cancer screening, and the technician turns to you and says, "We're finished, but if I push this button over here, the machine can detect even smaller cancers. But here's the hitch: You have to pay $700 if you want me to push this button."

"You'd be enraged," says Ellen Matloff, director of cancer genetic counseling at Yale University Cancer Center. "You'd want to know why you have to pay extra to push that button. Why didn't they just do it right the first time?"

Doctors and genetic counselors interviewed by CNN say that Myriad Genetics in Utah is doing something very similar with tests that determine if a woman has a potentially dangerous genetic abnormality linked to breast cancers.

Most breast cancers do not seem to be genetic. Instead, they're the result of cells gone wild for no apparent reason. However, some women get breast cancer because a bad gene runs in their families. When testing shows that a woman carries such a gene, she has a much higher chance of getting breast cancer. These women usually then get more frequent MRIs, ultrasounds and mammograms to detect a cancer, and sometimes even choose to remove their breasts to prevent a cancer from growing in the first place.

Myriad owns the patent on breast cancer genes and so is the only company that can test for them. It offers one test that catches most, but not all, abnormalities, and then charges nearly all patients $700 for a second test that catches the rest.

If a woman can't afford the $700 fee, she may miss an abnormality, which could mean the difference between life and death.

"What Myriad's doing -- charging extra for this test -- is really sleazy," Matloff says. "They're collecting blood money off my patients."

Myriad defends the $700 charge for its second test, called BART, even though many patients can't afford it and insurance won't pay for it.

"The BART test is based on different and separate technology," Rebecca Chambers, a Myriad spokeswoman, wrote in an e-mail to CNN. "[It's] based on a sophisticated new technology developed exclusively by Myriad."

She added that Myriad is trying to persuade insurance companies to pay for the test and that it offers financial assistance to patients who meet certain criteria, and monthly interest-free payments to those why do owe the $700 fee.

"Myriad's mission is to improve the patient's quality of life and to save lives," she added in the e-mail.

Understanding the furor

To understand the anger and bitterness that patients, doctors and genetic counselors harbor toward Myriad, it's important to know the basics of genetic testing.

In 1996, Myriad offered its first test for breast cancer genetic abnormalities. Known as the BRCA test, it's been revolutionary and has saved countless lives: If the test reveals that a woman has a genetic abnormality, it means she has a very high chance of getting breast cancer in the future, and some women then opt to remove their breasts as a pre-emptive strike against cancer.

Women who test positive for BRCA also sometimes opt to have their ovaries removed, since having a breast cancer gene abnormality gives them a higher-than-normal chance of getting ovarian cancer as well.

"Genetic testing has been a godsend for so many women," Matloff says.

Myriad calls its test the Comprehensive BRACAnalysis, but it soon became clear that it wasn't truly comprehensive. It did not catch all genetic abnormalities linked to cancer, and so in 2006, the company began selling BART, the newer test that catches genetic defects that the original test misses. Doctors and counselors expected Myriad to offer BART as part of its original test, but instead the company offers it separately and charges nearly everyone $700 to take it.

"This is so irresponsible of Myriad," says Molly Klein, director of genetic counseling at Piedmont Hospital in Atlanta.

She and other genetic counselors have been fighting to get Myriad to stop the $700 charge. They say they worry that women who tested negative under the first test feel assured that they don't have a bad gene when in fact they might, and wouldn't know they're at increased risk for getting breast cancer.

Klein and other genetic counselors say that when Myriad came up with an improvement in its colon cancer test, it wrapped it into its original screening at one price. The counselors say they think Myriad handled the breast cancer test differently, charging a separate fee, because it has no competition.

"From a business perspective, I guess I understand why Myriad is doing what they're doing, because this is a good chunk of money for them," says Kristen Shannon, the senior genetic counselor at the Massachusetts General Hospital Cancer Center. "But I feel really strongly that Myriad is doing the wrong thing."

"That accusation is incorrect," Chambers wrote in an e-mail to CNN.

"I'm so angry"

For Eileen Kelly and Kathleen Maxian, money wasn't the issue.

The two sisters were stunned three years ago when Kelly was diagnosed with breast cancer at age 40. They breathed a sigh of relief when Kelly tested negative for the BRCA gene using Myriad's original test. This meant Kelly's cancer was a fluke, and not something her sister or other relatives needed to worry about.

Then two years later, at the age of 47, Maxian found out she had ovarian cancer. Surgeons removed her ovaries and found the cancer had spread to her abdomen. After chemotherapy, the cancer came back a year later.

"I told my surgeon my sister had genetic testing, but it came back negative," Maxian says. "My surgeon just hung her head down and shook it back and forth. I was like, 'What? How weird is that?' "

The surgeon told Maxian that her sister's test might have been incomplete. She instructed Maxian to ask her sister, who lives in Atlanta, to find out if she'd received the second test, BART, in addition to the original breast cancer genetic test.

Kelly found out she had not had not received BART. She went back to Piedmont Hospital to have it done, and the test was positive. Maxian and her father then had BART, and it turns out that they, too, carry a genetic abnormality.

Women who have genetic abnormalities like Maxian's have a 50% to 85% chance of getting breast cancer, and a 10% to 40% chance of getting ovarian cancer. She says that if her sister had had BART from the beginning, she also would have taken the test, and the positive result would have made her remove her breasts and ovaries "in a minute."

"If BART had been done from the beginning, it could have saved Kathleen from getting ovarian cancer," says Dr. Nefertiti duPont, Maxian's surgeon at the Roswell Park Cancer Institute in Buffalo, New York.

"It could have prevented my cancer, or at least caught it early," Maxian adds. "Now my cancer is so advanced, I have only a 20% chance of being alive five years from now. I'm so angry."

Klein, the genetic counselor at Piedmont Hospital, says she never mentioned BART to Kelly, nor to most of the women who came in for testing at that time. She says information from Myriad led her to believe that BART mutations were extremely rare among women like Kelly without an extremely strong family history of breast or ovarian cancer. When some women do have a very strong family history, Myriad will do a BART analysis for free as part of its original test, and has spent $20 million on these tests.

"We were left with the impression that BART wasn't necessary for families like Eileen's," Klein says. "It just didn't seem urgent."

But over time, it's become clear that Myriad might have been wrong about who needs BART testing, counselors say. Several studies, such as one done by Shannon at the Massachusetts General Hospital Cancer Center, show that a substantial number of women had BART mutations even without a very strong family history. Now, Klein and others offer BART to all their patients, but many can't do it because of the cost.

"This is all really frustrating," Klein says. "We know we're missing women out there with BART mutations because they can't afford to pay. If you miss just one BART mutation, that woman could be in danger, and so could her mother, her sisters and her other relatives."

"It's heartbreaking," says Mollie Hutton, Maxian's genetic counselor at the Roswell Park Cancer Institute. "It's so sad that now Kathleen is fighting for her life when something could have been done to avoid it. It's just crappy."

Chambers, the Myriad spokeswoman, says studies show "less than one percent of all women tested" have a BART mutation.

What to do when you get breast cancer genetic testing

If you're about to get breast cancer genetic testing, specifically ask if you'll receive BART testing.

If you've had breast cancer genetic testing, don't assume you received the BART test.

Also, don't assume that the place where you had the testing will get back in touch with you to let you know about BART. CNN contacted four genetic testing centers, each of which did something different: One center quickly contacted all patients to tell them about BART; another contacted only patients they considered high risk; the third contacted patients three years after BART became available; and the fourth still hasn't contacted patients to tell them about BART.

Genetic counselors recommend that you call the place where you had testing every year or so to see if there have been any improvements in the test.

Most women will have to decide whether they want to spend $700 to get BART testing.

Eileen Kelly wishes she'd had the opportunity to spend that money.

"I'm so mad at Myriad. It's even hard just to talk about it," Kelly says, starting to cry. "A test could have put the information in our hands that could have prevented my sister's cancer. It's frustrating and really hard to comprehend."

Aaron Cooper contributed to this report.



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Technology

Senin, 24 Oktober 2011

Nutrition labels 'in wrong place'

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AppId is over the quota
24 October 2011 Last updated at 07:46 GMT Nutrition label on a packet of biscuits Nutrition labels should be placed in the centre of food packaging, rather than in one corner, if shoppers are going to read them, says a US study.

Using an eye-tracking device, researchers from Minnesota also found that the average consumer only reads the top part of a food content label.

They studied 203 people while looking at 64 different grocery products on a computer screen.

The Journal of the American Dietetic Association published the results.

In the study, participants were asked to view three elements on a typical food product - the nutrition contents label, a picture and list of ingredients, and a description of the product with price and quantity information - on the left, on the right or in the centre of the packaging.

One third of the participants each saw the nutrition label in one of those positions and were asked whether they would consider buying the product.

Participants were aware that their eye movements would be tracked, but unaware that the study was investigating nutrition information.

Position test

When the nutrition contents label was presented in the centre, subjects read one or more sections of 61% of the labels compared with 37% and 34% of labels among participants randomly assigned to view labels on the left and right hand sides of the screen.

In addition, labels in the centre of the product were seen to receive more than 30% more viewing time than the same labels when positioned to one side of the product.

The researchers also observed that most consumers view the contents of the label nearest the top more than those at the bottom of the label.

The study says that many more participants said they looked at the content of the nutrition labels than actually did when their viewing of the labels was tracked and measured.

Only 9% of participants actually looked at the calorie count for almost all products in the study, compared to 33% who said they did when asked.

Researchers Dan Graham and Robert Jeffrey, from the division of epidemiology and community health at the University of Minnesota, said: "The results of this study suggest that consumers have a finite attention span for Nutrition Facts labels.

"Although most consumers did view labels, very few consumers viewed every component on any label.

"These results differed from the self-reported survey responses describing typical grocery shopping and health behaviours submitted by the participants."

They also said the location of the labels on the packaging made a difference.

"Consumers are more likely to view centrally located labels and nutrients nearer the label's top.

"Because knowing the amounts of key nutrients that foods contain can influence consumers to make healthier purchases, prominently positioning key nutrients, and labels themselves, could substantially impact on public health."

A spokesman from the Food and Drink Federation said they were aware that consumers often do not read labels.

"Any research that adds to our understanding of what would encourage consumers to use the information provided is welcomed.

"The transferability of this research to the UK shopping experience is unclear, as the study is based on computer simulation and uses information in a format that is quite different from what is found on packs in the UK."

But she said: "We support the provision of clear, simple front of pack nutrition labelling which the authors conclude would address the concerns raised by their research."



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Sabtu, 01 Oktober 2011

Viewpoint: Why Dr. Feelgood Isn't Always Wrong

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AppId is over the quota

Dr. Conrad Murray, personal physician to Michael Jackson, is currently on trial in Los Angeles for involuntary manslaughter, two years after the death of the singer — of "acute propofol intoxication" — was officially ruled a homicide by the L.A. County coroner's office.

Let me start by saying that administering the anesthetic drug propofol for sleep, as Murray has acknowledged doing for Jackson, even while the doctor feared his patient had developed an addiction to it, is inexcusable. The drug has no medical use outside the operating room and anesthesia isn't "sleep." It's more like a controlled form of coma.

But that being said, giving addicts the drugs they want isn't always quackery. In fact, it can often be lifesaving. Indeed, "Dr. Feelgood," a term of disparagement that has long been used to describe doctors who inadvertently or deliberately prescribe psychoactive drugs to addicts, may sometimes do real good.

Increasingly, evidence suggests that maintenance prescribing, as it's known, may benefit addicts at least as much as direct efforts to get them to quit entirely. Simply giving addicts more drugs sounds like the last thing that could improve health or spur recovery, but the pharmacology of opioids like heroin and OxyContin — the kinds of drugs that contribute to the vast majority of overdose deaths in the U.S. — makes it practical.

Once a person has become dependent on these drugs, a steady, regular, maintenance dose will no longer produce a "high" or any impairment. Rather it will allow addicts to function normally. Studies increasingly support the use of substitute drugs like methadone and buprenorphine (Suboxone, Subutex) for opioid addicts, as well as the use of addicts' actual drug of choice like heroin. As a handful of studies also suggest, there may be reason to hope that amphetamine could possibly even help methamphetamine and cocaine addicts.

MORE: Can Amphetamines Help Cure Cocaine Addiction?

Just like pain patients who can take steady doses of painkillers to function, addicts who are given methadone, heroin, buprenorphine or other opioids aren't impaired. They don't have to spend their lives seeking street drugs, a supply that is unpredictable and unlike medical-grade drugs possibly impure, which can only do more harm. When addicts are stabilized and required to see the doctor regularly for prescriptions, their health and lives improve. Research even shows that when addicts are maintained on long-acting drugs like methadone, their stress response is reduced in a way that isn't seen with abstinence.

Hundreds of studies on methadone and buprenorphine use in opioid addicts support their efficacy. Maintenance prescribing reduces crime, mortality, and HIV and hepatitis rates more than abstinence-based treatment does, and is equally good at improving other outcomes like employment. Research also finds that when methadone clinics are shuttered or when maintenance prescribing is arbitrarily limited, overdose deaths and crime rates go up.

Moreover, for the most intractable cases of addiction, studies have so overwhelmingly supported the prescribing of heroin that countries including Germany, Switzerland, Denmark, the Netherlands and the U.K. now include it among their treatment options.

So, should we be praising our Dr. Feelgoods, rather than putting them in prison? Can we solve the crisis of prescription-drug addiction by legalizing maintenance prescribing of drugs other than methadone or buprenorphine? Can we prevent people from lying or committing crime to get drugs, simply by allowing them get them honestly?

The answers aren't clear, but here's one thing that is: the way we're currently dealing with the misuse of opioids isn't working. Legitimate pain patients are getting squeezed by measures meant to root out addicts. Overdose deaths are rising. Physicians who discover addicts in their practices tend simply to cut them off, often without even providing a referral to treatment. There's no evidence that any of this helps.

MORE:

Without Abstinence" href="http://healthland.time.com/2010/09/28/addiction-files-recovering-from-drug-addiction-without%c2%a0abstinence/">Addiction Files: Recovering From Drug Addiction, Without Abstinence

In fact, a study by Project Lazarus, a comprehensive program aimed at reducing overdose deaths in North Carolina, found that when one physician who was believed to be a Feelgood enabler of addicts had his medical license suspended, his former patients began dying of overdose at a greater rate than when he was practicing.

Other doctors refused to see these abandoned patients: they were viewed as addicts simply because they had been associated with a "bad" doctor. It's hard to know why they died, however. Did some pain patients commit suicide because of unrelieved agony, as has been known to happen in other cases in which doctors suddenly stopped prescribing (either voluntarily or due to legal issues)? Or were they addicts with a reduced tolerance?

The study's authors suggest that, whether the people who died were suffering from pain, addiction or both, being cut off abruptly lowered their tolerance and put them at risk for overdose. Project Lazarus has since established a buprenorphine maintenance clinic in an attempt to prevent similar problems in future cases.

Thoughtless prescribing — like giving out propofol — is clearly dangerous. But maintenance should be a widely available option. Expanding the drugs available for maintenance use and the settings in which maintenance is permitted should be studied.

Maia Szalavitz is a health writer at TIME.com. Find her on Twitter at @maiasz. You can also continue the discussion on TIME Healthland's Facebook page and on Twitter at @TIMEHealthland.



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Peliculas Online

Rabu, 28 September 2011

Diets fail 'because advice is wrong'

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AppId is over the quota
22 September 2011 Last updated at 02:58 GMT By Michelle Roberts Health reporter, BBC News tape measure Weighing and measuring yourself regularly helps track your weight-loss progress Eat less and you will lose weight.

This simple piece of advice is true, but it's one that many of us struggle to follow.

It is easy to blame a lack of willpower or a penchant for sugary, fat-laden snacks. And often weight does pile back on because people revert to their old way of eating too much of the wrong foods.

But researchers say the reason so many of us relapse and fail on diets is because we have unrealistic expectations.

And this is not our fault but that of experts, because the advice they give us is flawed.

Long slog

Most people start dieting with the notion that they will start to see results fast.

Experts tell us that if we cut around 500 calories from our daily diet, or burn them off exercising, then we can expect to lose 1lb (0.5kg) in weight every week.

Continue reading the main story
Studies show that somewhere between 50% and 80% of dieters will put weight back on”

End Quote Dr Kevin Hall of the US National Institutes for Health The British Dietetics Association, the NHS and the American Dietetic Association all say losing weight at this rate is "about right" and that if you stick at it for 12 months, for example, you will shed about 52 lb (26kg).

But US researchers from the National Institutes for Health say this is a gross overestimation because the calculation used is flawed.

They say it takes much longer to lose the weight - around three years to be precise, according to their work published in The Lancet.

For example, a year of dieting will result in only half of the amount of weight loss that experts currently predict.

Dr Kevin Hall and colleagues say this explains why many of us give up within months, because we expect unrealistic results that cannot be achieved.

Studies of outpatient weight loss programmes show most dieters peak at six months with the pounds starting to creep back on after this.

Continue reading the main story Calories displayed on food packaging The recommended daily calorie intake for men is 2,500 and for women is 2,000The lowest intake per day recommended for men is 1,500 and for women is 1,200 calories, unless they are in a medically supervised settingSome, incorrectly, attribute this to the body getting used to having less food and metabolism slowing down. The dieter then feels that the regime is no longer working and often gives up altogether.

Alternatively, as the slimmer begins to see the weight falling off in the early months they are so pleased with their achievement that they begin to relax and the diet slips. But because weight loss is slow there is a lag phase where weight continues to drop even though the person is now eating more. The dieter then mistakenly concludes that they don't need to be so rigid with their diet in order to lose weight.

But eventually, the weight will catch up with them and they may well find they are now heavier than they were when they first started the diet.

Dr Hall explains: "The slow timescale for weight change is responsible for the gradual weight regain over many years despite the fact that the original lifestyle was resumed within the first year.

"Studies show that somewhere between 50% and 80% of dieters will put weight back on."

He says professionals need to change the advice that they give to dieters so they don't fall into this trap.

Continue reading the main story
We all recommend it - it's what we are taught. But I don't know what the scientific evidence for it is”

End Quote Helen Bond from the British Dietetic Association "If you can give a realistic picture, that can inform people and help them make choices."

Dr Hall says the error occurs because the "500 calorie-cut a day" sum fails to take account of how metabolism changes as we diet.

The mathematic equation relies on the assumption that one pound of fat contains 3,500 calories, so to lose one pound a week a person should consume approximately 3,500 fewer calories a week, or 500 fewer calories a day.

But in fact, weight loss is not this steady.

Natural fluctuations

Using knowledge about how the human body responds to changes of diet and physical activity, Dr Hall's team have created a computer program that they say gives a more realistic and reliable prediction of weight loss.

Their calculations reflect the fact that one person may lose weight faster or slower than another, even when they eat the same diet and do the same exercise.

For example, heavier people can expect greater weight change with the same change in diet, but it will take them longer to reach a stable body weight than people carrying less fat.

Plus the body adapts rapidly to a reduced calorie diet, regardless of the type of food eliminated to get this reduction.

This means that all diets with similarly reduced energy content will have the same effect in the short term, whether the food cut out is fat or sugary carbohydrates.

woman eating a chocolate bar Habits can be hard to break

Dr Hall said: "We tested it on about 100 people and it gave a good fit. It was pretty accurate, whereas the old rule does not fall anywhere near.

"This means we can use it to make realistic predictions.

"The rough rule of thumb to go by is 10 calories per day per pound. And it takes a year to lose half of the excess weight and three years to get to 95%."

It's not clear why the advice was adopted in the first place.

Helen Bond, from the British Dietetic Association, admitted: "We all recommend it - it's what we are taught. But I don't know what the scientific evidence for it is.

"It stems from how much energy it takes to burn fat. A lot of diets are not proven by science."

She said some dieters might find it depressing to be told that it takes far longer to get weight down than previously thought.

"It's not very motivating to tell someone that if they cut their intake by 10 calories a day every day for the next three years they will lose a pound of weight.

"But saying 'cut out your daily habit of a 250-calorie chocolate bar and you will lose about 25 pounds and, if you stick at it, the weight will stay off' - that is."

However, Dr Hall says the computer model also shows how people can achieve more rapid weight loss if that is what they desire.

For example, someone could follow a very strict diet for the first year to get rid of a large bulk of their excess weight and then switch to a less restrictive diet to continue and maintain the weight loss. Adding in extra exercise will also have an impact.

At the end of the day, it still boils down to willpower. There is no quick fix to dieting and if you want it to work you need to stick at it, says Dr Hall.

A healthy diet is for life, not just post-Christmas.



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Peliculas Online

Senin, 26 September 2011

Diets fail 'because advice is wrong'

AppId is over the quota
AppId is over the quota
22 September 2011 Last updated at 02:58 GMT By Michelle Roberts Health reporter, BBC News tape measure Weighing and measuring yourself regularly helps track your weight-loss progress Eat less and you will lose weight.

This simple piece of advice is true, but it's one that many of us struggle to follow.

It is easy to blame a lack of willpower or a penchant for sugary, fat-laden snacks. And often weight does pile back on because people revert to their old way of eating too much of the wrong foods.

But researchers say the reason so many of us relapse and fail on diets is because we have unrealistic expectations.

And this is not our fault but that of experts, because the advice they give us is flawed.

Long slog

Most people start dieting with the notion that they will start to see results fast.

Experts tell us that if we cut around 500 calories from our daily diet, or burn them off exercising, then we can expect to lose 1lb (0.5kg) in weight every week.

Continue reading the main story
Studies show that somewhere between 50% and 80% of dieters will put weight back on”

End Quote Dr Kevin Hall of the US National Institutes for Health The British Dietetics Association, the NHS and the American Dietetic Association all say losing weight at this rate is "about right" and that if you stick at it for 12 months, for example, you will shed about 52 lb (26kg).

But US researchers from the National Institutes for Health say this is a gross overestimation because the calculation used is flawed.

They say it takes much longer to lose the weight - around three years to be precise, according to their work published in The Lancet.

For example, a year of dieting will result in only half of the amount of weight loss that experts currently predict.

Dr Kevin Hall and colleagues say this explains why many of us give up within months, because we expect unrealistic results that cannot be achieved.

Studies of outpatient weight loss programmes show most dieters peak at six months with the pounds starting to creep back on after this.

Continue reading the main story Calories displayed on food packaging The recommended daily calorie intake for men is 2,500 and for women is 2,000The lowest intake per day recommended for men is 1,500 and for women is 1,200 calories, unless they are in a medically supervised settingSome, incorrectly, attribute this to the body getting used to having less food and metabolism slowing down. The dieter then feels that the regime is no longer working and often gives up altogether.

Alternatively, as the slimmer begins to see the weight falling off in the early months they are so pleased with their achievement that they begin to relax and the diet slips. But because weight loss is slow there is a lag phase where weight continues to drop even though the person is now eating more. The dieter then mistakenly concludes that they don't need to be so rigid with their diet in order to lose weight.

But eventually, the weight will catch up with them and they may well find they are now heavier than they were when they first started the diet.

Dr Hall explains: "The slow timescale for weight change is responsible for the gradual weight regain over many years despite the fact that the original lifestyle was resumed within the first year.

"Studies show that somewhere between 50% and 80% of dieters will put weight back on."

He says professionals need to change the advice that they give to dieters so they don't fall into this trap.

Continue reading the main story
We all recommend it - it's what we are taught. But I don't know what the scientific evidence for it is”

End Quote Helen Bond from the British Dietetic Association "If you can give a realistic picture, that can inform people and help them make choices."

Dr Hall says the error occurs because the "500 calorie-cut a day" sum fails to take account of how metabolism changes as we diet.

The mathematic equation relies on the assumption that one pound of fat contains 3,500 calories, so to lose one pound a week a person should consume approximately 3,500 fewer calories a week, or 500 fewer calories a day.

But in fact, weight loss is not this steady.

Natural fluctuations

Using knowledge about how the human body responds to changes of diet and physical activity, Dr Hall's team have created a computer program that they say gives a more realistic and reliable prediction of weight loss.

Their calculations reflect the fact that one person may lose weight faster or slower than another, even when they eat the same diet and do the same exercise.

For example, heavier people can expect greater weight change with the same change in diet, but it will take them longer to reach a stable body weight than people carrying less fat.

Plus the body adapts rapidly to a reduced calorie diet, regardless of the type of food eliminated to get this reduction.

This means that all diets with similarly reduced energy content will have the same effect in the short term, whether the food cut out is fat or sugary carbohydrates.

woman eating a chocolate bar Habits can be hard to break

Dr Hall said: "We tested it on about 100 people and it gave a good fit. It was pretty accurate, whereas the old rule does not fall anywhere near.

"This means we can use it to make realistic predictions.

"The rough rule of thumb to go by is 10 calories per day per pound. And it takes a year to lose half of the excess weight and three years to get to 95%."

It's not clear why the advice was adopted in the first place.

Helen Bond, from the British Dietetic Association, admitted: "We all recommend it - it's what we are taught. But I don't know what the scientific evidence for it is.

"It stems from how much energy it takes to burn fat. A lot of diets are not proven by science."

She said some dieters might find it depressing to be told that it takes far longer to get weight down than previously thought.

"It's not very motivating to tell someone that if they cut their intake by 10 calories a day every day for the next three years they will lose a pound of weight.

"But saying 'cut out your daily habit of a 250-calorie chocolate bar and you will lose about 25 pounds and, if you stick at it, the weight will stay off' - that is."

However, Dr Hall says the computer model also shows how people can achieve more rapid weight loss if that is what they desire.

For example, someone could follow a very strict diet for the first year to get rid of a large bulk of their excess weight and then switch to a less restrictive diet to continue and maintain the weight loss. Adding in extra exercise will also have an impact.

At the end of the day, it still boils down to willpower. There is no quick fix to dieting and if you want it to work you need to stick at it, says Dr Hall.

A healthy diet is for life, not just post-Christmas.



View the original article here



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