eMedicine Specialties > Plastic Surgery > Breast
Author: Garry S Brody, MD, MSc, FACS, Professor Emeritus, Department of Surgery, Division of Plastic Surgery, Keck School of Medicine, University of Southern California
Updated: May 1, 2009
Background
The number of women in the United States who have breast implants is unknown, but current estimates derived from national surveys range up to more than 6 million. This represents more than 5% of the adult female population. The American Society of Plastic Surgeons (ASPS) collects information annually on plastic surgery procedures performed by its members. In 2008, approximately 307,000 women received breast implants for cosmetic breast augmentation and 111,000 for reconstruction of congenital or postmastectomy deformities.1 These data do not include those procedures (mostly cosmetic) performed by non plastic surgeons such as otolaryngologists, general surgeons, gynecologists, and others.
Following adverse publicity in the early 1990s, interest in the procedure fell significantly, especially for gel-filled devices, but it seems to have recovered incrementally. According to the ASPS, in 2008, 53% of total breast implants were filled with saline; 47% were filled with silicone.1
Prior to 1963, various plastic foam materials were used; for breast augmentation, however, it became apparent that the air cells would collapse and, combined with tissue ingrowth, shrink and harden the device. These materials were wrapped in plastic film to minimize this effect to no avail. Amazingly, some of these implants were so well tolerated that they have stayed in place to this day.
The modern silicone breast implant has been available since 1963 and has gone through an evolution of change and improvement. Several types of devices, with many variations, shapes and styles within each class, are now available or under testing for US Food and Drug Administration (FDA) approval. Basic to all implants is a silicone rubber (elastomer) shell, which can be single or double, smooth or textured, barrier-coated, or covered with polyurethane foam. The foam-covered devices have not been available in the United States since 1990 but are still marketed in Europe.
The contents are either factory-filled with silicone gel of various consistencies or inflated at surgery with normal saline. One brand that was manufactured overseas was prefilled with saline at the factory. It was briefly marketed in the United States but was later withdrawn when the FDA denied approval.
The double-lumen devices consist of concentric balloons that contain silicone in one chamber and saline in the other. The only one still in use is the Becker, which has an outer layer of gel and an inner balloon that is valved to permit postoperative gradual inflation with saline. This is termed a "permanent tissue expander," since it permits gradual and temporary overinflation to create the pocket and then can be left in as a permanent implant after the size is adjusted appropriately. At this writing, the Becker devices are not generally available in the United States until current FDA mandated studies are evaluated.2 For more information on expandable implants, see eMedicine article Uses of the Postoperatively Adjustable Implant in Aesthetic Breast Surgery.
In 1990, the FDA placed a moratorium on gel-filled implant use for cosmetic augmentation. They remained available for reconstruction and replacement, but mandated extensive record keeping, follow-up, and IRB approval were required for use. In 2006, after extensive study and analysis, the FDA deemed the device safe for all augmentation and reconstructive purposes, but they continue to require tracking of patients.
Saline Implants
Saline filled implants are available as empty silicone balloonlike devices to be filled with normal saline at the time of surgery. This permits subtle size adjustments to compensate for asymmetry between the breasts. They are less popular than silicone implants, as they often may have a less natural feel. If the patient has very little breast tissue or only a skin covering after mastectomy, unsightly wrinkles and folds of the device may be visible on the breast. This is more common when the surface is textured.
Silicone Gel Implants
Three generations of basic design of this device have been created, with many variations within each type.
First generation
The first models to be marketed had envelopes of thick, smooth-walled silicone elastomer made in 2 sections, filled with a viscous silicone gel material (dimethylsiloxane) and glued together. They were available in only three sizes: small, medium, and large. In the first few years, surgeons believed that the device required attachment to the tissues to prevent migration. Scar ingrowth for fixation was accomplished by patches of material (eg, Dacron mesh or perforated silicone) attached to the back of the device or by an outer covering of polyurethane foam. The Dacron and silicone patches were subsequently found to be unnecessary; they actually detracted from the quality of the result. Some patches or tabs created a stress point that led to tears of the envelope. Fixation patches were eliminated in the early 1970s.
Second generation
Manufacturers varied the gel consistency and shell thickness in an attempt to improve performance. Beginning in the mid-1970s, the shells were made thinner and the gel less viscous (ie, more "responsive"), primarily in an ill-conceived attempt to control hardening from scar shrinkage (capsular contracture.) This trend reversed in the early 1980s when it was recognized as not effective in reducing contracture and as resulting in a more fragile device. Most were broken 10 years later.
Third generation
New formulations of the shell and gel contents became available that were stronger and had a second barrier coat of diphenyl silicone. This coating almost totally eliminated so-called "gel bleed" or diffusion of small amounts of the silicone oil through the implant shell. The gel content also was made more viscous and cohesive.
In 1989, textured-surface shells that many surgeons hoped would minimize the incidence of unwanted firmness from capsular contracture became available. Recent studies are somewhat confusing regarding whether this was effective. The textured implants had the disadvantage of a higher rupture rate than the more traditional smooth shells and often produced visible wrinkles in the breast in women with very little overlying tissue to mask the ripples. Because of these shortcomings and lack of solid evidence that these devices were softer, they have become much less popular in recent years.
Polyurethane-covered implants
In the late 1960s, a variation of the device was developed containing a polyurethane sponge coating over an otherwise standard gel-filled implant. Although the coating originally was planned as a fixation layer, many surgeons came to believe that the foam cover resulted in a decreased incidence (or at least a delayed onset) of capsular contracture. These implants also evolved in shape and design, culminating in the early 1980s with the Meme and Optimam styles. In April 1991, the manufacturer voluntarily withdrew the foam-covered implants from the market.3
One style, the MemeME, had a unique construction. It had no true shell, but a skin of sorts was formed in situ by spraying the surface with silicone containing extra catalyst prior to curing. This increased the crosslinking of the surface to create a shell-like membrane. The polyurethane foam was then shaped and sealed over the surface. Implants of this particular type were known to occasionally extrude some of their gel contents through the foam when squeezed. This is a possible explanation for reports of blood being found within the substance of the gel in apparently intact implants. The MemeME model was marketed from 1983-1988.
Other filler materials
While silicone remains the only available shell material, new filler substances were in use in Europe and South America and, at one time, were under development or in experimental trial in the United States. Various hydrogels and a pure form of triglycerides were the 2 main formulations. The major advantage of the triglyceride formulation (Trilucent) was that it had a Z number (measure of radiolucency) similar to that of fat, thus resulting in little or no compromise of mammography. Another fill substance, polyvinyl pyrrolidone in saline, was briefly available, under the trade name Misty Gold. None of these products is currently available in the United States. At this time, only silicone gel or saline-filled models are available for use in the United States.
Recent developments
In late 2006, a new formulation of silicone gel filler called MemoryGel (Mentor Corp, Santa Barbara, Calif) gained FDA approval.4 This gel implant is thicker and more cohesive so as to minimize gel spread in the case of rupture and to resist scar shrinkage that would deform its contour. When cut, the gel retains its shape and doesn’t run. This device has a doughy feel to it.
Currently available devices in the United States are saline- or silicone-filled implants with either textured or smooth surfaces. They come in round or tear drop shapes with a choice of 3 different projections. Only 2 companies, Mentor Corporation and Allergen (a successor to McGhan and Inamed), have FDA approval to market these devices in the United States.
The implants produced currently are much improved devices compared to earlier units. The shell is still made of an outer layer of a mix of dimethyl siloxane and amorphous silica with an inner barrier coat of diphenyl siloxane to minimize silicone gel bleed. The shells, on testing for breakage, exceed the American Society for Testing and Materials (ASTM) requirements by more than 300%. The gel is more cohesive, varying from a standard 60% crosslinking to 80% for the more cohesive type nicknamed "gummy bear" (because of is consistency similar to the candy).
As evidenced by sales figures prior to the moratorium, and now following their release for cosmetic purposes, approximately 80-85% of surgeons and patients prefer the quality of results obtained by gel implants, making them the implants of choice. In 1997, sales figures for Europe, where usage was unrestricted, show a distribution of 70% for gel, 15% for saline, and 15% for alternate fills such as triglycerides (then still available) and hydrogels for cosmetic use.
Safety
Silicone is probably the most studied implantable material available today. After over 35 well-conducted studies from many countries, it seems certain that this material does not cause disease.
The results of more than 7 long-term follow-up studies show that women with implants have a reduced incidence of breast cancer than is otherwise expected in the general population.
No hard evidence reveals that a broken implant is harmful.
Almost all of the problems that can occur with breast implants, such as infection, hardening, extrusion, and malposition are related to the surgical procedure or the patient's own biology, not the device.
Summary
A great deal of recent safety research combined with more than 40 years of clinical experience has proven the value and relative safety of breast implants. Aside from the unique adverse effect of capsular contracture, the complication rate of this surgery approaches that of any clean elective procedure.
To date, no convincing evidence exists of any systemic disorder that can be attributed to silicone. As these are manmade devices, they have a failure rate and, in some patients, can require a significant amount of surgical maintenance. As with all natural body parts, these artificial substitutes may be subject to injury or disease and, when viewed from that perspective, have favorable risk-benefit characteristics
Wednesday, March 9, 2011
Friday, March 4, 2011
New Obesity Index Proposed, But Further Work Needed
From Heartwire
Lisa Nainggolan
March 3, 2011 (Los Angeles, California) — US researchers have developed a new index of adiposity that they say is a more accurate measure of body fat than the traditionally used body-mass index (BMI); the latter is calculated by dividing weight by height [1].
Using measurements of hip circumference and height, the new body adiposity index (BAI) can be used to reflect percentage of body fat for adult men and women of differing ethnicities, without numerical correction or assessment of weight, say Dr Richard N Bergman (University of Southern California, Los Angeles) and colleagues in their paper published online March 3, 2011 in Obesity.
It remains to be seen if the BAI is a more useful predictor of health outcome than other indexes of body adiposity, including the BMI.
However, they note that further work will be needed to extend and confirm their findings--tested in Mexican Americans and African Americans--to whites and other ethnic groups and to assess the role of the new index in children. And "it remains to be seen if the BAI is a more useful predictor of health outcome, in both males and females, than other indexes of body adiposity, including the BMI itself."
Height and Hip Size Most Strongly Relate to Percentage Adiposity
"We were interested in determining whether we could find an index of body adiposity that at least in some ways may be better than the BMI, which has been around since the 1840s" and is not a very accurate measure of adiposity in individual patients, Bergman explained to heartwire .
BMI is particularly inaccurate in people with elevated lean body mass, such as athletes, and in children, and it cannot be generalized among different ethnic groups, he and his colleagues note.
Bergman et al are not the first to propose an alternative to BMI. Waist circumference is widely thought to be a better indicator of cardiovascular risk than BMI, although some studies have shown them to be equally predictive.
Other examples include the waist-to-hip ratio (WHR) and the waist-to-hip-to-height index, which have both been forwarded as potentially better measures of obesity than BMI. But critics have said that it is difficult and time-consuming to get very accurate measurements of waist and hip circumference and height and that BMI has remained popular because it is simple and fast.
We looked at which variables most strongly related to percent adiposity, and they were height and hip size.
In their study, Bergman and colleagues used a large database, BetaGene, which consisted of relatives of Mexican Americans with gestational diabetes, to determine whether there might be a better index. They chose the Mexican American population because of its prevalence in Los Angeles, observing, "Most of the world population is nonwhite."
"We looked at which variables most strongly related to percent adiposity, and they were height and hip size. Because these variables were uncorrelated, we proposed a new index, the BAI, based upon these measures alone," Bergman explains.
BAI Will Be Easy to Calculate
"We showed that the BAI, calculated as (hip circumference/height1.5)–18, was a good predictor of percent fat and worked for men and women," he continues. The BAI also yielded the percentage of fat itself, rather than just a correlate (or index) of it, which is what the BMI does, he notes. The BAI was validated against the "gold standard" of dual-energy X-ray absorption (DEXA).
"It will be very easy for a physician or a nurse practitioner to work out this index for individual patients, using a calculator, a computer program, or an iPhone app," Bergman says.
The researchers then went on to corroborate their findings in another population, the Triglyceride and Cardiovascular Risk in African Americans (TARA) study, and found that the behavior of the BAI was quite similar between the blacks in that population and the Hispanics in BetaGene.
"Thus, we believe that we have presented evidence of accuracy at least in two ethnic populations, and further work on the generalizability of BAI to other groups is under way," they state. It will also be important to see whether the index can reliably forecast percentage of adiposity in children and predict risk of cardiovascular disease, they note.
Lisa Nainggolan
March 3, 2011 (Los Angeles, California) — US researchers have developed a new index of adiposity that they say is a more accurate measure of body fat than the traditionally used body-mass index (BMI); the latter is calculated by dividing weight by height [1].
Using measurements of hip circumference and height, the new body adiposity index (BAI) can be used to reflect percentage of body fat for adult men and women of differing ethnicities, without numerical correction or assessment of weight, say Dr Richard N Bergman (University of Southern California, Los Angeles) and colleagues in their paper published online March 3, 2011 in Obesity.
It remains to be seen if the BAI is a more useful predictor of health outcome than other indexes of body adiposity, including the BMI.
However, they note that further work will be needed to extend and confirm their findings--tested in Mexican Americans and African Americans--to whites and other ethnic groups and to assess the role of the new index in children. And "it remains to be seen if the BAI is a more useful predictor of health outcome, in both males and females, than other indexes of body adiposity, including the BMI itself."
Height and Hip Size Most Strongly Relate to Percentage Adiposity
"We were interested in determining whether we could find an index of body adiposity that at least in some ways may be better than the BMI, which has been around since the 1840s" and is not a very accurate measure of adiposity in individual patients, Bergman explained to heartwire .
BMI is particularly inaccurate in people with elevated lean body mass, such as athletes, and in children, and it cannot be generalized among different ethnic groups, he and his colleagues note.
Bergman et al are not the first to propose an alternative to BMI. Waist circumference is widely thought to be a better indicator of cardiovascular risk than BMI, although some studies have shown them to be equally predictive.
Other examples include the waist-to-hip ratio (WHR) and the waist-to-hip-to-height index, which have both been forwarded as potentially better measures of obesity than BMI. But critics have said that it is difficult and time-consuming to get very accurate measurements of waist and hip circumference and height and that BMI has remained popular because it is simple and fast.
We looked at which variables most strongly related to percent adiposity, and they were height and hip size.
In their study, Bergman and colleagues used a large database, BetaGene, which consisted of relatives of Mexican Americans with gestational diabetes, to determine whether there might be a better index. They chose the Mexican American population because of its prevalence in Los Angeles, observing, "Most of the world population is nonwhite."
"We looked at which variables most strongly related to percent adiposity, and they were height and hip size. Because these variables were uncorrelated, we proposed a new index, the BAI, based upon these measures alone," Bergman explains.
BAI Will Be Easy to Calculate
"We showed that the BAI, calculated as (hip circumference/height1.5)–18, was a good predictor of percent fat and worked for men and women," he continues. The BAI also yielded the percentage of fat itself, rather than just a correlate (or index) of it, which is what the BMI does, he notes. The BAI was validated against the "gold standard" of dual-energy X-ray absorption (DEXA).
"It will be very easy for a physician or a nurse practitioner to work out this index for individual patients, using a calculator, a computer program, or an iPhone app," Bergman says.
The researchers then went on to corroborate their findings in another population, the Triglyceride and Cardiovascular Risk in African Americans (TARA) study, and found that the behavior of the BAI was quite similar between the blacks in that population and the Hispanics in BetaGene.
"Thus, we believe that we have presented evidence of accuracy at least in two ethnic populations, and further work on the generalizability of BAI to other groups is under way," they state. It will also be important to see whether the index can reliably forecast percentage of adiposity in children and predict risk of cardiovascular disease, they note.
Monday, February 28, 2011
The Importance of 'Don't' in Inducing Ethical Employee Behavior
Research & Ideas : Harvard Business School
Published: February 28, 2011
Author: Carmen Nobel
Executive Summary:
In a new study, HBS professors Francesca Gino and Joshua D. Margolis look at two ways that companies can encourage ethical behavior: the promotion of good deeds or the prevention of bad deeds. It turns out that employees tend to act more ethically when focused on what not to do. That can be problematic in firms where success is commonly framed in terms of advancement of positive outcomes rather than prevention of bad ones. Key concepts include:
* In general, there are two ways a company can encourage ethical conduct among its employees: either the promotion of good actions and outcomes or the prevention of bad ones.
* Through several experiments, the professors found that inducing a prevention focus will lead to ethical behavior more than inducing a promotion focus.
* In encouraging ethical behavior among employees, it behooves firms to consider focusing on preventing negative outcomes, not only in creating a code of ethics but also in setting goals and framing task directives.
In trying to encourage good moral conduct, it's common for a company to come up with a list of don'ts—wording policies such that they focus on unethical behavior employees should avoid rather than on ethical acts they should strive to achieve. Don't cheat. Don't lie. It's a tendency that dates back to the Ten Commandments, the vast majority (eight) of which dictate what thou shalt not do.
Meanwhile, in virtually every other aspect of business there is a focus on what to do. Do meet sales projections. Do outperform competitors. Do impress the boss by getting things done.
"The default tendency is for companies to frame goals in terms of promotion, and what we show here is that this might actually lead to cheating as a side effect."
The dichotomy raises an important question: If employees are generally focused on the benefits of getting things done, will they be attentive to messages about what not to do? Harvard Business School professor Joshua D. Margolis draws a parallel to stage directions in a high-school play. "If you're always told when to enter, you might skip over the one time you're told to exit," he says.
Margolis and fellow HBS professor Francesca Gino explore the issue in a new research paper, "Bringing Ethics into Focus: How Regulatory Focus and Risk Preferences Influence (Un)ethical Behavior," in which they distinguish between two ways a company can encourage ethical conduct among its employees: either the promotion of being ethical or the prevention of being unethical. (The paper will be published in the academic journal, "Organizational Behavior and Human Decision Processes.")
"Since the Enron scandal, there has been a lot of research across disciplines on why even good people do wrong," Margolis says. "But we have relatively little research to date that says, so, what do you do about it? That's the big game that we're hunting. What are some simple implementations or changes managers can introduce in their organizations to encourage good behavior?"
Promotion or prevention?
Through a series of experiments with college and graduate students, which are detailed in the paper, Gino and Margolis set out to induce individuals to focus on either promotion or prevention via a series of situational cues. They then studied whether the subconscious adoption of either a promotion or a prevention focus could affect an individual's behavior.
The researchers now contend that a person's focus, either promotion or prevention, can indeed influence his or her ethical behavior at any given time.
"I think the main message of the paper is that with situational cues, you can trigger one type of motivation versus the other," Gino says. "And because of this motivation, people end up cheating more or less. What we find is that the cues that induce a promotion focus—this idea of attaining high levels of performance—can lead to more cheating than prevention-focus types of framework or cues."
In one experiment, students had to come up with anagrams under the time pressure of 90 seconds per round, over a series of six rounds, with the understanding that they would be scoring themselves at the end of the test—and that they would be rewarded for high performance.
"In each round, participants were given a series of seven letters and asked to create as many words as possible," the paper explains. "The last series of letters was presented in a different order for each participant so that we could track who cheated and to what extent by comparing workbooks and answer sheets with participants' self-reported performance."
The students learned that they would each receive a Scrabble dictionary to check their work, after which they would fill out an answer sheet to report their performance. But before providing the dictionaries, the researchers distributed a pencil-and-paper maze to each student, in which the goal was to help a trapped cartoon mouse find its way out.
In some mazes, a picture of a piece of cheese sat outside the exit, next to a hole in the wall where the mouse could escape. This was meant to induce a promotion focus: Go get that reward! In other cases, in lieu of cheese, there was a menacing cartoon owl hovering above the maze, such that it behooved the mouse to reach the exit so as not to become bird food. That maze was meant to induce a prevention focus: Don't get killed!
Once they had completed the mazes, the students returned to the task of scoring themselves on the anagram test. They were told to pay themselves from the envelope on their desks according to their performance.
The results showed that the students who completed the cheese maze were far more likely to overstate their results, and to reward themselves accordingly, than those who completed the maze with the scary owl—82 percent (37 out of 45 participants) and 39 percent (16 out of 41 participants), respectively.
In a separate experiment, the researchers demonstrated that they could induce a promotion or prevention focus simply by phrasing the goals of the study in two different ways. Some students received promotion-based instructions that included the following statement, focusing on advancement: "This research project is being conducted to advance the ideals and aspirations pursued by applied social science." Others received a statement focusing on compliance: "Statement of Research Code of Conduct—This research project is being conducted with strict adherence to the standards and obligations required of applied social science."
Again, the students who were steered toward a promotion focus were more likely to cheat on the activities that followed. In other words, inducing a prevention focus may lead to more ethical behavior than inducing a promotion focus. Company executives may want to take note.
"The default tendency is for companies to frame goals in terms of promotion, and what we show here is that this might actually lead to cheating as a side effect," Gino says. "So the idea is to maybe revise those policies in terms of prevention so that they could trigger [ethical behavior]."
In yet another experiment, the researchers repeated the anagram tests, the mazes, and the monetary rewards with a different set of students, but then they added a wrinkle: After rewarding themselves from the envelopes on their desks, the students had the opportunity to donate some of their winnings to National Public Radio.
Tracking moral and immoral actions
The results showed that a much larger number of the student participants donated money to NPR in the promotion focus (10 out of 33) than in the prevention focus (2 out of 33). In other words, while inducing a promotion focus seemed to induce unethical acts, it also led to higher levels of virtuous behaviors to make up for those unethical acts.
"So there is evidence for the fact that people like to feel that they're in balance when it comes to ethics," Gino says. "People are guided by their moral compass when facing ethical dilemmas. And they keep track of their moral and immoral actions. There's a sense that there's a moral scale inside of you, and you want to keep it balanced."
Eventually, Gino and Margolis plan to work within several companies to discover particular ways to incorporate a prevention focus into their bottom line, while still encouraging financial success. In the meantime, managers can be mindful of striking a balance between morals and money when setting goals and offering rewards.
"When you're a manager helping to set up the conditions in which people operate, be attuned to the messages you're sending," Margolis says. "If the message is, 'Be sure not to step over the line, but hit those numbers,' don't be shocked if people forget the first message. You need to be clear about penalties even as you are clear about goal setting. You want a healthy setting between those."
About the author
Carmen Nobel is a senior editor at HBS Working Knowledge.
Published: February 28, 2011
Author: Carmen Nobel
Executive Summary:
In a new study, HBS professors Francesca Gino and Joshua D. Margolis look at two ways that companies can encourage ethical behavior: the promotion of good deeds or the prevention of bad deeds. It turns out that employees tend to act more ethically when focused on what not to do. That can be problematic in firms where success is commonly framed in terms of advancement of positive outcomes rather than prevention of bad ones. Key concepts include:
* In general, there are two ways a company can encourage ethical conduct among its employees: either the promotion of good actions and outcomes or the prevention of bad ones.
* Through several experiments, the professors found that inducing a prevention focus will lead to ethical behavior more than inducing a promotion focus.
* In encouraging ethical behavior among employees, it behooves firms to consider focusing on preventing negative outcomes, not only in creating a code of ethics but also in setting goals and framing task directives.
In trying to encourage good moral conduct, it's common for a company to come up with a list of don'ts—wording policies such that they focus on unethical behavior employees should avoid rather than on ethical acts they should strive to achieve. Don't cheat. Don't lie. It's a tendency that dates back to the Ten Commandments, the vast majority (eight) of which dictate what thou shalt not do.
Meanwhile, in virtually every other aspect of business there is a focus on what to do. Do meet sales projections. Do outperform competitors. Do impress the boss by getting things done.
"The default tendency is for companies to frame goals in terms of promotion, and what we show here is that this might actually lead to cheating as a side effect."
The dichotomy raises an important question: If employees are generally focused on the benefits of getting things done, will they be attentive to messages about what not to do? Harvard Business School professor Joshua D. Margolis draws a parallel to stage directions in a high-school play. "If you're always told when to enter, you might skip over the one time you're told to exit," he says.
Margolis and fellow HBS professor Francesca Gino explore the issue in a new research paper, "Bringing Ethics into Focus: How Regulatory Focus and Risk Preferences Influence (Un)ethical Behavior," in which they distinguish between two ways a company can encourage ethical conduct among its employees: either the promotion of being ethical or the prevention of being unethical. (The paper will be published in the academic journal, "Organizational Behavior and Human Decision Processes.")
"Since the Enron scandal, there has been a lot of research across disciplines on why even good people do wrong," Margolis says. "But we have relatively little research to date that says, so, what do you do about it? That's the big game that we're hunting. What are some simple implementations or changes managers can introduce in their organizations to encourage good behavior?"
Promotion or prevention?
Through a series of experiments with college and graduate students, which are detailed in the paper, Gino and Margolis set out to induce individuals to focus on either promotion or prevention via a series of situational cues. They then studied whether the subconscious adoption of either a promotion or a prevention focus could affect an individual's behavior.
The researchers now contend that a person's focus, either promotion or prevention, can indeed influence his or her ethical behavior at any given time.
"I think the main message of the paper is that with situational cues, you can trigger one type of motivation versus the other," Gino says. "And because of this motivation, people end up cheating more or less. What we find is that the cues that induce a promotion focus—this idea of attaining high levels of performance—can lead to more cheating than prevention-focus types of framework or cues."
In one experiment, students had to come up with anagrams under the time pressure of 90 seconds per round, over a series of six rounds, with the understanding that they would be scoring themselves at the end of the test—and that they would be rewarded for high performance.
"In each round, participants were given a series of seven letters and asked to create as many words as possible," the paper explains. "The last series of letters was presented in a different order for each participant so that we could track who cheated and to what extent by comparing workbooks and answer sheets with participants' self-reported performance."
The students learned that they would each receive a Scrabble dictionary to check their work, after which they would fill out an answer sheet to report their performance. But before providing the dictionaries, the researchers distributed a pencil-and-paper maze to each student, in which the goal was to help a trapped cartoon mouse find its way out.
In some mazes, a picture of a piece of cheese sat outside the exit, next to a hole in the wall where the mouse could escape. This was meant to induce a promotion focus: Go get that reward! In other cases, in lieu of cheese, there was a menacing cartoon owl hovering above the maze, such that it behooved the mouse to reach the exit so as not to become bird food. That maze was meant to induce a prevention focus: Don't get killed!
Once they had completed the mazes, the students returned to the task of scoring themselves on the anagram test. They were told to pay themselves from the envelope on their desks according to their performance.
The results showed that the students who completed the cheese maze were far more likely to overstate their results, and to reward themselves accordingly, than those who completed the maze with the scary owl—82 percent (37 out of 45 participants) and 39 percent (16 out of 41 participants), respectively.
In a separate experiment, the researchers demonstrated that they could induce a promotion or prevention focus simply by phrasing the goals of the study in two different ways. Some students received promotion-based instructions that included the following statement, focusing on advancement: "This research project is being conducted to advance the ideals and aspirations pursued by applied social science." Others received a statement focusing on compliance: "Statement of Research Code of Conduct—This research project is being conducted with strict adherence to the standards and obligations required of applied social science."
Again, the students who were steered toward a promotion focus were more likely to cheat on the activities that followed. In other words, inducing a prevention focus may lead to more ethical behavior than inducing a promotion focus. Company executives may want to take note.
"The default tendency is for companies to frame goals in terms of promotion, and what we show here is that this might actually lead to cheating as a side effect," Gino says. "So the idea is to maybe revise those policies in terms of prevention so that they could trigger [ethical behavior]."
In yet another experiment, the researchers repeated the anagram tests, the mazes, and the monetary rewards with a different set of students, but then they added a wrinkle: After rewarding themselves from the envelopes on their desks, the students had the opportunity to donate some of their winnings to National Public Radio.
Tracking moral and immoral actions
The results showed that a much larger number of the student participants donated money to NPR in the promotion focus (10 out of 33) than in the prevention focus (2 out of 33). In other words, while inducing a promotion focus seemed to induce unethical acts, it also led to higher levels of virtuous behaviors to make up for those unethical acts.
"So there is evidence for the fact that people like to feel that they're in balance when it comes to ethics," Gino says. "People are guided by their moral compass when facing ethical dilemmas. And they keep track of their moral and immoral actions. There's a sense that there's a moral scale inside of you, and you want to keep it balanced."
Eventually, Gino and Margolis plan to work within several companies to discover particular ways to incorporate a prevention focus into their bottom line, while still encouraging financial success. In the meantime, managers can be mindful of striking a balance between morals and money when setting goals and offering rewards.
"When you're a manager helping to set up the conditions in which people operate, be attuned to the messages you're sending," Margolis says. "If the message is, 'Be sure not to step over the line, but hit those numbers,' don't be shocked if people forget the first message. You need to be clear about penalties even as you are clear about goal setting. You want a healthy setting between those."
About the author
Carmen Nobel is a senior editor at HBS Working Knowledge.
Analysis Suggests Back Disease May Run in Families
From Medscape Medical News
Norra MacReady
February 4, 2011 — In an analysis of a database of more than 2 million people, first-degree and third-degree relatives of people with lumbar disc disease had a significantly increased relative risk of developing the back condition themselves compared with expected rates for the general population. "The results of this study support a heritable predisposition to lumbar disc disease," lead author Alpesh A. Patel, MD, and colleagues from the departments of Orthopaedics and Biomedical Informatics, University of Utah School of Medicine, Salt Lake City, report in the February 2 issue of the Journal of Bone and Joint Surgery.
Low back pain is common and costly — its estimated lifetime risk in the United States is 84%, with an annual cost that exceeds $100 billion — yet its etiology remains incompletely understood, the authors write. Several earlier studies have hinted at a familial predisposition, but "we are aware of no study that has evaluated the familial clustering of lumbar disc disease on a population-based, multigenerational level."
To test the hypothesis that lumbar disc disease may be inherited, the authors analyzed data from both the Utah Population Database, which permits the tracking of medical information on the founding pioneers of Utah and their descendents, and the University of Utah Health Sciences Center data warehouse, which has diagnosis and procedure data on all patients treated at the University Hospital. Together, the databases contain information on more than 2.4 million patients. Only patients and control participants with at least 3 generations of genealogical data were included in the study.
Of those individuals, 1254 people had at least 1 diagnosis of lumbar disc disease or lumbar disc herniation, along with the requisite genealogical data. The authors tested for heritability in 2 ways: by estimating the relative risk for lumbar disease in relatives and by determining a genealogical index of familiality (GIF). They compared their findings in affected families with the expected results for the general population of Utah.
First-degree relatives of people with lumbar disc disease had a relative risk of 4.15 of having the disease themselves (95% confidence interval [CI], 2.82 - 6.10; P < .001). In third-degree relatives, the relative risk was 1.46 (95% CI, 1.06 - 2.01; P = .027). Relative risk was slightly elevated in second-degree relatives, at 1.15, but this was not significant (95% CI, .71 - 1.87; P = .60), perhaps because of limitations in the data.
The GIF tests the hypothesis that there is no excess familial clustering, or relatedness, of the phenotype of interest by measuring excess relationships between pairs of patients compared with pairs of control participants. "It is not the absolute value of the GIF statistic that reveals excess relatedness of disease, but the relative value of the case-GIF to the control-GIF," the authors explain. In this analysis, the case overall GIF was 3.05 compared with a mean control GIF of 2.51 (P < .001 for overall GIF), suggesting "a significant excess of relationships among patients compared with controls."
The investigators relied on International Classification of Diseases, Ninth Revision, codes to identify patients, so diagnostic accuracy may have varied, depending on physician specialty and experience, they noted. Also, they were unable to determine disease severity and response to treatment. Genetically, the population of Utah is similar to the US population and to the northern European population from which the founders of Utah came, so the findings may be generalized to those groups.
Now that a genetic predisposition to lumbar disc disease has been identified, the authors conclude, "identification of the specific genetic products responsible for lumbar disc disease may help in the development of potential biologic interventions to prevent and/or treat lumbar disc disease in the population at large."
In an accompanying editorial published online, David A. Wong, MD, from the Denver Spine Center, Greenwood Village, Colorado, commends Dr. Patel and colleagues for their study design and conclusion. Dr. Wong remarks on the future possibilities that may lead researchers to identify specific genes responsible for spine and other musculoskeletal disorders, akin to what is currently known about breast cancer. He states: "We can look forward to more genetic research in the area of the spine. Inevitably better treatments are likely to be found. Perhaps the treatment for so-called black disc disease is lurking on the horizon."
One or more of the authors received outside support or grants in excess of $10,000 from the National Institutes of Health-National Library of Medicine to support the research or preparation for this study. No other relevant financial disclosures were made.
J Bone Joint Surg Am. 2011;93:225-229. Abstract
Norra MacReady
February 4, 2011 — In an analysis of a database of more than 2 million people, first-degree and third-degree relatives of people with lumbar disc disease had a significantly increased relative risk of developing the back condition themselves compared with expected rates for the general population. "The results of this study support a heritable predisposition to lumbar disc disease," lead author Alpesh A. Patel, MD, and colleagues from the departments of Orthopaedics and Biomedical Informatics, University of Utah School of Medicine, Salt Lake City, report in the February 2 issue of the Journal of Bone and Joint Surgery.
Low back pain is common and costly — its estimated lifetime risk in the United States is 84%, with an annual cost that exceeds $100 billion — yet its etiology remains incompletely understood, the authors write. Several earlier studies have hinted at a familial predisposition, but "we are aware of no study that has evaluated the familial clustering of lumbar disc disease on a population-based, multigenerational level."
To test the hypothesis that lumbar disc disease may be inherited, the authors analyzed data from both the Utah Population Database, which permits the tracking of medical information on the founding pioneers of Utah and their descendents, and the University of Utah Health Sciences Center data warehouse, which has diagnosis and procedure data on all patients treated at the University Hospital. Together, the databases contain information on more than 2.4 million patients. Only patients and control participants with at least 3 generations of genealogical data were included in the study.
Of those individuals, 1254 people had at least 1 diagnosis of lumbar disc disease or lumbar disc herniation, along with the requisite genealogical data. The authors tested for heritability in 2 ways: by estimating the relative risk for lumbar disease in relatives and by determining a genealogical index of familiality (GIF). They compared their findings in affected families with the expected results for the general population of Utah.
First-degree relatives of people with lumbar disc disease had a relative risk of 4.15 of having the disease themselves (95% confidence interval [CI], 2.82 - 6.10; P < .001). In third-degree relatives, the relative risk was 1.46 (95% CI, 1.06 - 2.01; P = .027). Relative risk was slightly elevated in second-degree relatives, at 1.15, but this was not significant (95% CI, .71 - 1.87; P = .60), perhaps because of limitations in the data.
The GIF tests the hypothesis that there is no excess familial clustering, or relatedness, of the phenotype of interest by measuring excess relationships between pairs of patients compared with pairs of control participants. "It is not the absolute value of the GIF statistic that reveals excess relatedness of disease, but the relative value of the case-GIF to the control-GIF," the authors explain. In this analysis, the case overall GIF was 3.05 compared with a mean control GIF of 2.51 (P < .001 for overall GIF), suggesting "a significant excess of relationships among patients compared with controls."
The investigators relied on International Classification of Diseases, Ninth Revision, codes to identify patients, so diagnostic accuracy may have varied, depending on physician specialty and experience, they noted. Also, they were unable to determine disease severity and response to treatment. Genetically, the population of Utah is similar to the US population and to the northern European population from which the founders of Utah came, so the findings may be generalized to those groups.
Now that a genetic predisposition to lumbar disc disease has been identified, the authors conclude, "identification of the specific genetic products responsible for lumbar disc disease may help in the development of potential biologic interventions to prevent and/or treat lumbar disc disease in the population at large."
In an accompanying editorial published online, David A. Wong, MD, from the Denver Spine Center, Greenwood Village, Colorado, commends Dr. Patel and colleagues for their study design and conclusion. Dr. Wong remarks on the future possibilities that may lead researchers to identify specific genes responsible for spine and other musculoskeletal disorders, akin to what is currently known about breast cancer. He states: "We can look forward to more genetic research in the area of the spine. Inevitably better treatments are likely to be found. Perhaps the treatment for so-called black disc disease is lurking on the horizon."
One or more of the authors received outside support or grants in excess of $10,000 from the National Institutes of Health-National Library of Medicine to support the research or preparation for this study. No other relevant financial disclosures were made.
J Bone Joint Surg Am. 2011;93:225-229. Abstract
Tuesday, February 15, 2011
Updated USDA Dietary Guidelines Released C
From Medscape Education Clinical Briefs
News Author: Emma Hitt, PhD
CME Author: Laurie Barclay, MD
Clinical Context
Achieving and maintaining a healthy weight require eating and physical activity patterns focused on consuming fewer calories, making informed food choices, and increasing participation in physical exercise. Benefits of such a program also include lower a risk for chronic disease and improvements in overall health.
The Dietary Guidelines for Americans, 2010 discusses these strategies and issues recommendations for Americans 2 years and older, including those at increased risk for chronic disease.
The guidelines are tailored to the food preferences, cultural traditions, and customs of the many and diverse groups residing in the United States and also offer specific recommendations for groups based on age, sex, and special considerations such as pregnancy.
Study Highlights
* Overweight and obesity can be prevented and/or reduced through improved eating and physical activity behaviors.
* Body weight can be managed by controlling total calorie intake.
* For overweight or obese individuals, management of body weight requires consuming fewer calories from foods and beverages.
* Physical activity should be increased, and time spent in sedentary activities should be reduced.
* Appropriate caloric balance needs to be maintained during each life stage, including childhood, adolescence, adulthood, pregnancy and breast-feeding, and older age.
* Daily sodium intake should be reduced to less than 2300 mg in the general population and to less than 1500 mg for those 51 years and older; African Americans; or individuals with hypertension, diabetes, or chronic kidney disease.
* Less than 10% of calories should come from saturated fatty acids; these should be replaced with monounsaturated and polyunsaturated fatty acids.
* Dietary cholesterol intake should not exceed 300 mg per day.
* Trans-fatty acid intake should be minimized by limiting foods containing partially hydrogenated oils and other solid fats.
* Calorie intake should be reduced from solid fats, added sugars, and foods containing refined grains, especially those containing solid fats, added sugars, and sodium.
* If alcohol is consumed, it should be limited to 1 drink per day or less for women and 2 drinks per day or less for men, and only by adults of legal drinking age.
* Within daily caloric needs, vegetable and fruit intake should be increased, especially dark-green, red, and orange vegetables; beans; and peas.
* At least half of all grains consumed should be whole grains, and refined grains should be replaced with whole grains whenever possible.
* Intake of fat-free or low-fat milk and milk products (eg, milk, yogurt, cheese, or fortified soy beverages) should be increased.
* Protein foods should include a variety of sources (eg, seafood, lean meat and poultry, eggs, beans and peas, soy products, and unsalted nuts and seeds), with seafood replacing some meat and poultry when feasible.
* Protein foods higher in solid fats should be replaced with those that are lower in solid fats and calories and/or are sources of oils.
* Oils should replace solid fats when possible.
* Because American diets may be lacking in potassium, dietary fiber, calcium, and vitamin D, dietary sources of these should be increased by eating proportionately more vegetables, fruits, whole grains, and milk and milk products.
* Women of childbearing potential should favor foods supplying heme iron and vitamin C-rich foods to enhance iron absorption.
* In addition, they should consider additional iron sources and consume 400 μg per day of synthetic folic acid from fortified foods and/or supplements as well as foods rich in folate.
* Women who are pregnant or breast-feeding should consume 8 to 12 ounces seafood per week from a variety of seafood types, excluding tilefish, shark, swordfish, and king mackerel because of their high content of methyl mercury.
* Similarly, white (albacore) tuna intake should not exceed 6 ounces per week.
* Pregnant women should take an iron supplement recommended by their physician.
* Persons 50 years and older should consume vitamin B12-fortified foods (eg, fortified cereals) or dietary supplements.
Clinical Implications
* To achieve and sustain a healthy weight, the USDA and the US Department of Health and Human Services guidelines stress the importance of maintaining calorie balance with time by consuming only enough calories from foods and beverages to meet their needs and by being physically active.
* The USDA and the US Department of Health and Human Services guidelines also emphasize the need to consume nutrient-dense foods and beverages, while avoiding calorie-dense foods and beverages low in nutritional value.
News Author: Emma Hitt, PhD
CME Author: Laurie Barclay, MD
Clinical Context
Achieving and maintaining a healthy weight require eating and physical activity patterns focused on consuming fewer calories, making informed food choices, and increasing participation in physical exercise. Benefits of such a program also include lower a risk for chronic disease and improvements in overall health.
The Dietary Guidelines for Americans, 2010 discusses these strategies and issues recommendations for Americans 2 years and older, including those at increased risk for chronic disease.
The guidelines are tailored to the food preferences, cultural traditions, and customs of the many and diverse groups residing in the United States and also offer specific recommendations for groups based on age, sex, and special considerations such as pregnancy.
Study Highlights
* Overweight and obesity can be prevented and/or reduced through improved eating and physical activity behaviors.
* Body weight can be managed by controlling total calorie intake.
* For overweight or obese individuals, management of body weight requires consuming fewer calories from foods and beverages.
* Physical activity should be increased, and time spent in sedentary activities should be reduced.
* Appropriate caloric balance needs to be maintained during each life stage, including childhood, adolescence, adulthood, pregnancy and breast-feeding, and older age.
* Daily sodium intake should be reduced to less than 2300 mg in the general population and to less than 1500 mg for those 51 years and older; African Americans; or individuals with hypertension, diabetes, or chronic kidney disease.
* Less than 10% of calories should come from saturated fatty acids; these should be replaced with monounsaturated and polyunsaturated fatty acids.
* Dietary cholesterol intake should not exceed 300 mg per day.
* Trans-fatty acid intake should be minimized by limiting foods containing partially hydrogenated oils and other solid fats.
* Calorie intake should be reduced from solid fats, added sugars, and foods containing refined grains, especially those containing solid fats, added sugars, and sodium.
* If alcohol is consumed, it should be limited to 1 drink per day or less for women and 2 drinks per day or less for men, and only by adults of legal drinking age.
* Within daily caloric needs, vegetable and fruit intake should be increased, especially dark-green, red, and orange vegetables; beans; and peas.
* At least half of all grains consumed should be whole grains, and refined grains should be replaced with whole grains whenever possible.
* Intake of fat-free or low-fat milk and milk products (eg, milk, yogurt, cheese, or fortified soy beverages) should be increased.
* Protein foods should include a variety of sources (eg, seafood, lean meat and poultry, eggs, beans and peas, soy products, and unsalted nuts and seeds), with seafood replacing some meat and poultry when feasible.
* Protein foods higher in solid fats should be replaced with those that are lower in solid fats and calories and/or are sources of oils.
* Oils should replace solid fats when possible.
* Because American diets may be lacking in potassium, dietary fiber, calcium, and vitamin D, dietary sources of these should be increased by eating proportionately more vegetables, fruits, whole grains, and milk and milk products.
* Women of childbearing potential should favor foods supplying heme iron and vitamin C-rich foods to enhance iron absorption.
* In addition, they should consider additional iron sources and consume 400 μg per day of synthetic folic acid from fortified foods and/or supplements as well as foods rich in folate.
* Women who are pregnant or breast-feeding should consume 8 to 12 ounces seafood per week from a variety of seafood types, excluding tilefish, shark, swordfish, and king mackerel because of their high content of methyl mercury.
* Similarly, white (albacore) tuna intake should not exceed 6 ounces per week.
* Pregnant women should take an iron supplement recommended by their physician.
* Persons 50 years and older should consume vitamin B12-fortified foods (eg, fortified cereals) or dietary supplements.
Clinical Implications
* To achieve and sustain a healthy weight, the USDA and the US Department of Health and Human Services guidelines stress the importance of maintaining calorie balance with time by consuming only enough calories from foods and beverages to meet their needs and by being physically active.
* The USDA and the US Department of Health and Human Services guidelines also emphasize the need to consume nutrient-dense foods and beverages, while avoiding calorie-dense foods and beverages low in nutritional value.
Alcohol Kills More Than AIDS, TB or Violence-WHO
From Reuters Health Information
By Stephanie Nebehay
GENEVA (Reuters Health) Feb 11 - Alcohol causes nearly 4% of deaths worldwide, more than AIDS, tuberculosis or violence, the World Health Organization warned on Friday.
Rising incomes have triggered more drinking in heavily populated countries in Africa and Asia, including India and South Africa, and binge drinking is a problem in many developed countries, the United Nations agency said.
Yet alcohol control policies are weak and remain a low priority for most governments despite drinking's heavy toll on society from road accidents, violence, disease, child neglect and job absenteeism, it said.
Approximately 2.5 million people die each year from alcohol related causes, the WHO said in its "Global Status Report on Alcohol and Health."
"The harmful use of alcohol is especially fatal for younger age groups and alcohol is the world's leading risk factor for death among males aged 15-59," the report found.
In Russia and the Commonwealth of Independent States (CIS), every fifth death is due to harmful drinking, the highest rate.
Binge drinking is now prevalent in Brazil, Kazakhstan, Mexico, Russia, South Africa and Ukraine, and rising elsewhere, according to the WHO.
"Worldwide, about 11% of drinkers have weekly heavy episodic drinking occasions, with men outnumbering women by four to one. Men consistently engage in hazardous drinking at much higher levels than women in all regions," the report said.
Health ministers from the WHO's 193 member states agreed last May to try to curb binge drinking and other growing forms of excessive alcohol use through higher taxes on alcoholic drinks and tighter marketing restrictions.
DISEASE AND INJURY
Alcohol is a causal factor in 60 types of diseases and injuries, according to WHO's first report on alcohol since 2004.
"Six or seven years ago we didn't have strong evidence of a causal relationship between drinking and breast cancer. Now we do," Dr. Vladimir Poznyak, head of WHO's substance abuse unit who coordinated the report, told Reuters Health.
Alcohol consumption rates vary greatly, from high levels in developed countries, to the lowest in North Africa, sub-Saharan Africa, and southern Asia, whose large Muslim populations often abstain from drinking.
Homemade or illegally produced alcohol -- falling outside governmental controls and tax nets -- accounts for nearly 30% of total worldwide adult consumption.
In France and other European countries with high levels of adult consumption, heavy episodic drinking is rather low, suggesting more regular but moderate drinking patterns.
One of the most effective ways to curb drinking, especially among young people, is to raise taxes, the report said. Setting age limits for buying and consuming alcohol, and regulating alcohol levels in drivers, also reduce abuse if enforced.
Some countries restrict marketing of alcoholic beverages or on the industry's sponsorship of sporting events.
"Yet not enough countries use these and other effective policy options to prevent death, disease and injury attributable to alcohol consumption," the WHO said.
Alcohol producers have said they recognize the importance of industry self-regulation to address alcohol abuse and promote curbs on drunk drinking and illegal underage drinking.
But the brewer SABMiller has warned that policy measures like minimum pricing and high excise taxes on alcohol could cause more public health harm than good by leading more people to drink homemade or illegally produced alcohol.
By Stephanie Nebehay
GENEVA (Reuters Health) Feb 11 - Alcohol causes nearly 4% of deaths worldwide, more than AIDS, tuberculosis or violence, the World Health Organization warned on Friday.
Rising incomes have triggered more drinking in heavily populated countries in Africa and Asia, including India and South Africa, and binge drinking is a problem in many developed countries, the United Nations agency said.
Yet alcohol control policies are weak and remain a low priority for most governments despite drinking's heavy toll on society from road accidents, violence, disease, child neglect and job absenteeism, it said.
Approximately 2.5 million people die each year from alcohol related causes, the WHO said in its "Global Status Report on Alcohol and Health."
"The harmful use of alcohol is especially fatal for younger age groups and alcohol is the world's leading risk factor for death among males aged 15-59," the report found.
In Russia and the Commonwealth of Independent States (CIS), every fifth death is due to harmful drinking, the highest rate.
Binge drinking is now prevalent in Brazil, Kazakhstan, Mexico, Russia, South Africa and Ukraine, and rising elsewhere, according to the WHO.
"Worldwide, about 11% of drinkers have weekly heavy episodic drinking occasions, with men outnumbering women by four to one. Men consistently engage in hazardous drinking at much higher levels than women in all regions," the report said.
Health ministers from the WHO's 193 member states agreed last May to try to curb binge drinking and other growing forms of excessive alcohol use through higher taxes on alcoholic drinks and tighter marketing restrictions.
DISEASE AND INJURY
Alcohol is a causal factor in 60 types of diseases and injuries, according to WHO's first report on alcohol since 2004.
"Six or seven years ago we didn't have strong evidence of a causal relationship between drinking and breast cancer. Now we do," Dr. Vladimir Poznyak, head of WHO's substance abuse unit who coordinated the report, told Reuters Health.
Alcohol consumption rates vary greatly, from high levels in developed countries, to the lowest in North Africa, sub-Saharan Africa, and southern Asia, whose large Muslim populations often abstain from drinking.
Homemade or illegally produced alcohol -- falling outside governmental controls and tax nets -- accounts for nearly 30% of total worldwide adult consumption.
In France and other European countries with high levels of adult consumption, heavy episodic drinking is rather low, suggesting more regular but moderate drinking patterns.
One of the most effective ways to curb drinking, especially among young people, is to raise taxes, the report said. Setting age limits for buying and consuming alcohol, and regulating alcohol levels in drivers, also reduce abuse if enforced.
Some countries restrict marketing of alcoholic beverages or on the industry's sponsorship of sporting events.
"Yet not enough countries use these and other effective policy options to prevent death, disease and injury attributable to alcohol consumption," the WHO said.
Alcohol producers have said they recognize the importance of industry self-regulation to address alcohol abuse and promote curbs on drunk drinking and illegal underage drinking.
But the brewer SABMiller has warned that policy measures like minimum pricing and high excise taxes on alcohol could cause more public health harm than good by leading more people to drink homemade or illegally produced alcohol.
Wednesday, February 9, 2011
Late Meals Associated With Obesity Risk
From Medscape Medical News
Norra MacReady
October 25, 2010 (San Diego, California) — A preference for late dinners might increase your risk for obesity, according to a small study presented here at Obesity 2010: The Obesity Society 28th Annual Scientific Meeting.
Rika Yokoyama, MS, and colleagues from the Health Care Food Research Laboratories of the Kao Corporation in Tokyo, Japan, compared the effects of early and late meals in a crossover study of 10 healthy Japanese men. The men consumed lunch at 1:00 pm and breakfast the following day at 8:00 am; they had dinner at 7:00 pm in the early dinner (ED) condition and at 10:00 pm in the late dinner (LD) condition. All meals were the same, and were consumed in a respiratory chamber, where the subjects' energy expenditure and fuel utilization were measured from 12:30 pm until 11:30 am the next day.
Blood metabolite levels were measured 1 hour after every meal, and the men rated their appetite hourly on a visual analogue scale (VAS), which ranged from 0 (not hungry at all) to 100 (as hungry as I've ever felt). The men had an average age of 40.4 (±6.9) years and an average body mass index of 23.1 (±2.2) kg/m2.
In the ED condition, average 23-hour energy expenditure was 1885 (±231) calories; in the LD condition it was 1837 (±228) calories (P < .05).
"We saw a sharp decline in postprandial energy expenditure, or diet-induced thermogenesis (DIT), during sleep after the LD condition. In the ED condition, the decline was more moderate," Ms. Yokoyama told Medscape Medical News. "Presumably, that was because in the ED condition, more time elapsed between dinner and bedtime. However, we could not identify the reason the DIT declined so sharply during sleep after the late dinner." Nor could the differences be traced to variations in physical activity; infrared motion sensors in the respiratory chamber did not detect any changes in physical activity between the conditions," she explained.
Insulin and blood glucose levels were markedly higher in the LD than in the ED condition after dinner (P < .01). Free fatty acids were also higher in the LD condition, and remained elevated until breakfast the following day. The authors concluded that eating dinner late was associated with lower total energy expenditure, hyperinsulinemia, and hyperglycemia, which over time could result in obesity.
Appetite scores on the VAS also were significantly higher just before dinner in the LD than in the ED condition (P < .05).
"This small study is provocative and may serve to suggest hypotheses that could and should be tested in larger studies before generalizable conclusions can be drawn," said Howard Eisenson, MD, associate professor of community and family medicine, and executive director of the Duke Diet and Fitness Center at Duke University School of Medicine in Durham, North Carolina.
Still, he said, "I believe that those specializing in the treatment of obesity will not be surprised that, at least in this small and very short-term study, a late night dinner seems to be associated with unfavorable changes in terms of weight management and risk for diabetes: increased appetite, decreased energy expenditure, and increased insulin and blood sugar levels. The implications for clinical practice are not yet clear, but this preliminary study should trigger broader research and may ultimately provide good evidence to support a personal and public health message."
Ms. Yokoyama and Dr. Eisenson have disclosed no relevant financial relationships.
Obesity 2010: The Obesity Society 28th Annual Scientific Meeting. Poster 202-P. Presented October 12, 2010.
Norra MacReady
October 25, 2010 (San Diego, California) — A preference for late dinners might increase your risk for obesity, according to a small study presented here at Obesity 2010: The Obesity Society 28th Annual Scientific Meeting.
Rika Yokoyama, MS, and colleagues from the Health Care Food Research Laboratories of the Kao Corporation in Tokyo, Japan, compared the effects of early and late meals in a crossover study of 10 healthy Japanese men. The men consumed lunch at 1:00 pm and breakfast the following day at 8:00 am; they had dinner at 7:00 pm in the early dinner (ED) condition and at 10:00 pm in the late dinner (LD) condition. All meals were the same, and were consumed in a respiratory chamber, where the subjects' energy expenditure and fuel utilization were measured from 12:30 pm until 11:30 am the next day.
Blood metabolite levels were measured 1 hour after every meal, and the men rated their appetite hourly on a visual analogue scale (VAS), which ranged from 0 (not hungry at all) to 100 (as hungry as I've ever felt). The men had an average age of 40.4 (±6.9) years and an average body mass index of 23.1 (±2.2) kg/m2.
In the ED condition, average 23-hour energy expenditure was 1885 (±231) calories; in the LD condition it was 1837 (±228) calories (P < .05).
"We saw a sharp decline in postprandial energy expenditure, or diet-induced thermogenesis (DIT), during sleep after the LD condition. In the ED condition, the decline was more moderate," Ms. Yokoyama told Medscape Medical News. "Presumably, that was because in the ED condition, more time elapsed between dinner and bedtime. However, we could not identify the reason the DIT declined so sharply during sleep after the late dinner." Nor could the differences be traced to variations in physical activity; infrared motion sensors in the respiratory chamber did not detect any changes in physical activity between the conditions," she explained.
Insulin and blood glucose levels were markedly higher in the LD than in the ED condition after dinner (P < .01). Free fatty acids were also higher in the LD condition, and remained elevated until breakfast the following day. The authors concluded that eating dinner late was associated with lower total energy expenditure, hyperinsulinemia, and hyperglycemia, which over time could result in obesity.
Appetite scores on the VAS also were significantly higher just before dinner in the LD than in the ED condition (P < .05).
"This small study is provocative and may serve to suggest hypotheses that could and should be tested in larger studies before generalizable conclusions can be drawn," said Howard Eisenson, MD, associate professor of community and family medicine, and executive director of the Duke Diet and Fitness Center at Duke University School of Medicine in Durham, North Carolina.
Still, he said, "I believe that those specializing in the treatment of obesity will not be surprised that, at least in this small and very short-term study, a late night dinner seems to be associated with unfavorable changes in terms of weight management and risk for diabetes: increased appetite, decreased energy expenditure, and increased insulin and blood sugar levels. The implications for clinical practice are not yet clear, but this preliminary study should trigger broader research and may ultimately provide good evidence to support a personal and public health message."
Ms. Yokoyama and Dr. Eisenson have disclosed no relevant financial relationships.
Obesity 2010: The Obesity Society 28th Annual Scientific Meeting. Poster 202-P. Presented October 12, 2010.
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