Here Is Another Piece Of The Weight-Control Puzzle

Controlling body weight is a complicated process, as any frustrated dieter might attest. But as scientists continue to investigate the brain's intricate neurocircuitry and its role in maintaining energy balance, they are forming a clearer picture of the myriad events that lead to weight gain and weight loss.
In the August 10 on-line issue of Nature Neuroscience, a study led by scientists at Beth Israel Deaconess Medical Center (BIDMC) identifies another piece of this complex puzzle, demonstrating that the neurotransmitter GABA --one of the master communicators among neurons – plays a role in controlling energy balance.
"Body weight maintenance is made up of three basic stages," explains the paper's senior author Bradford Lowell, MD, PhD, an investigator in the Division of Endocrinology, Diabetes and Metabolism at BIDMC whose laboratory is working to identify the specific neurocircuits responsible for controlling food intake and/or energy through functional neuroanatomical mapping studies.
"In the first stage, the brain receives sensory input from the body [including information provided by circulating hormones such as leptin and ghrelin and from fuels such as glucose and fatty acids]," says Lowell, who is also a Professor of Medicine at Harvard Medical School.
In the second stage, he adds, the brain integrates this sensory information with cues it has received from the environment (such as aromas and other enticements) along with information gathered from the organism's emotional state. Then, in the final stage, the brain's neurocircuitry takes over, enabling the brain to make appropriate alterations in food intake and energy expenditure in order to maintain energy balance – and prevent weight gain and obesity.
Previous work had primarily focused on identifying the neuropeptides involved in this process. And indeed, this group of neurotransmitters often proves essential to maintaining energy balance – but not always.
"It is well known that AgRP [Agouti-related protein] neurons play a critical role in feeding and energy balance regulation," explains Qingchun Tong, PhD, a postdoctoral fellow in the Lowell laboratory and the study's first author. "However, the deletion of AgRP and NPY [two neuropeptides released from the AgRP neurons] produces little metabolic effect."
An alternate theory proposed that release of the GABA neurotransmitter was mediating the function of AgRP neurons, an idea that had long been postulated but never examined.
To test this hypothesis, Tong and his colleagues generated a group of mice with disrupted release of GABA specifically from the AgRP neurons. As predicted, the genetically altered mice exhibited profound metabolic changes.
"The mice with AgRP neuron-specific disruption of GABA release were lean, had higher energy expenditure and showed resistance to diet-induced obesity," says Tong. "We also found that these animals showed reduced food intake response to the hormone ghrelin. This suggests to us that the neurocircuit engaging GABA release from the AgRP neurons mediates at least part of ghrelin's appetite-stimulating action."
A series of studies to examine the function of glutamate and GABA release from other groups of neurons are currently underway as investigators continue to dissect the brain's neurocircuitry.
"As these new findings demonstrate, GABA release is an important component that mediates the function of AgRP neurons," says Tong. "Discoveries such as this will ultimately help us to design an efficient strategy to tackle the current epidemic of obesity and metabolic disease."

The Lunch Box Diet Receives Rave Reviews From Elle Magazine

A new online diet has been created by a health and fitness expert that addresses health dangers and puts an end to risky yo-yo dieting. The Lunch Box diet has already received 5 star reviews from magazines like Elle Magazine, calling it ‘The best diet I have ever done’ and a ‘way of life’ (Jan 2008 Edition).
The Lunch Box Diet is designed to help the nation follow a healthy regime that maximises their energy levels and sharpens their minds. It offers an alternative to destructive dieting regimes based on a commonsense approach, an understanding of healthy eating and readily available, nutritional foods. Via direct contact with his clients, Simon has learned that the diet is sustainable, enjoyable and fits in with family life.
The no-nonsense diet allows people to eat their normal nourishing breakfast and dinner, while still shedding weight safely, and the eating plan is also a great maintenance regime for those who want to ensure their diet is energy fuelled, healthy and has lots of variety.
The Lunch Box Diet encourages grazing throughout the day to combat hunger pangs and uses super foods to provide the anti-oxidants necessary to prevent free radical damage, which combats premature aging of the skin, fights disease and maintains a healthy lifestyle. The diet is also built to be used according to active you are, so is perfect for those looking to sign up to gyms in the new-year.
Renowned personal fitness trainer Simon Lovell (UK Fitness expert to ‘Sport’ Magazine www.myfreesport.co.uk), the mastermind behind the Lunch Box Diet, has used his expertise to create an intelligently balanced plan. He explained: “The diet has snowballed from healthy eating plans I gave to my clients to supplement their fitness programmes. They worked so well that clients were passing them on to their friends and colleagues. I decided I had produced something special, quick to implement and, most importantly, doable.
“People can drop down to their ideal weight without compromising their health – it just takes a bit of direction and professional advice. There are definitely negative repercussions when using certain diets, which can have long-term effects on your health. I want to show people they can lose weight and actually improve their health as part of a whole lifestyle change.”
Sarah Panter, a Devon and Cornwall NHS worker, said: “The diet is so simple, tasty and great for me in the office. I lead a busy life and found I’d often be reaching for the crisps or chocolate bars. Now I’ve replaced those choices with a diet that ensures healthy alternatives are always on hand for when I get hunger pangs. It’s even helped with my Eczema”
Those wishing to download the diet can do so at www.thelunchboxdiet.com for $19.95

Toddlers Diet May Have Lifetime Impact on Health

According to new research from University of Calgary, what we eat in early childhood may have a lifelong impact on health. Scientists, in a surprising study, have found a direct link to food consumption as toddlers, and weight gain in adulthood. The seemingly innocuous act of giving your child a cheeseburger may set the stage for obesity, diabetes and heart disease in adulthood.
Faculty of Kinesiology researcher Dr. Raylene Reimer conducted the research. Dr. Reimer is one of the leading scientists who studies the origins of health and disease, or epigenetics, a blossoming area of health research.
Dr. Reimer explains, "My research has shown that the food we eat changes how active certain genes in our body are – what we call genetic expression. In particular, we believe that our diet has a direct influence on the genes that control how our bodies store and use nutrients. "There's a growing body of work that indicates a relationship between our health as adults and our early diet, and even our mother's diet. This research shows for the first time that our early childhood diet may have a huge impact on our health as adults."
The study is published in the London Journal of Physiology. The researchers examined the impact of diet in three groups of very young rats, providing them with three separate diets after weaning. One group received a high protein the second, a high fiber diet, and the third a control diet. When the rats reached adulthood, they were fed a typical Western diet consisting of high fat and sugar.
The surprising results showed that the rats that were given a high fiber diet when they were young, put on very little weight and body fat, when compared to the rats raised on a high protein diet.
Dr. Reimer believes the study…" clearly shows that the composition of early childhood diet may have a direct lifelong impact on genes that control metabolism and obesity risk. This study clearly indicates that diet composition alone can change the trajectory of circulating satiety hormones and metabolic pathways that influence how we gain weight or control blood sugar as adults."
In an accompanying conversation with Dr. Reimer, she discusses how diet changes the way our genes are expressed:
"For example we know that eating a high fiber diet increases your expression of the proglucagon gene. This gene is then used in thebody to make a hormone that decreases your food intake. In terms of diet's influence on epigenetics (which really means changes in addition to genetics) it changes the way the DNA code can be accessed by the machinery necessary to convert genes to their gene products (for example again the proglucagon gene producing GLP-1, the hormone that decreases food intake).
The study raises questions about the moral and ethical obligations of parents who make dietary choices for their children. According to Dr. Reimer, "Our best advice continues to be that mothers follow the Canadian National Guidelines for the Childbearing Years. "
From the standpoint of the researchers doing the work, there is no thought to laying blame on mothers for the rising obesity epidemic - but those who debate ethical issues in medicine will be forced to deal with questions of whether or not a parent will one day be held legally responsible for a future illness of its offspring if that parent ignored advice based on established links between diet/lifestyle and epigenetics" (the way genes express themselves).
Dr. Reimer also explains there are "many similarities between the rat models we use and humans in
terms of how obesity and diabetes develop."
Research that targets the developmental origins of health and disease may provide us with better insights into the increasing rates of obesity, cancer, and other global health issues that currently defy solution. The current research emphasizes the lifetime health impact of early childhood diets.

Government restrictions on weight loss surgeries limit access for poor

Weight Loss Surgery
Thresholds limiting weight loss (bariatric) surgeries to high-volume centers disproportionately restrict access for poor and underinsured patients, populations which are among the most in need of them, an analysis led by UT Southwestern Medical Center researchers shows.
Government-imposed restrictions currently mandate a 125-case annual threshold for facilities permitted to perform bariatric surgeries under Medicare and Medicaid because some studies have identified better outcomes for centers performing large volumes of bariatric surgeries. But most bariatric surgeries for the poor – about 60 percent – are performed in low-volume centers.
“Restricting surgeries to high-volume centers has the effect of limiting bariatric surgery as an option for many poor and underinsured who rely on Medicare and Medicaid,” said Dr. Edward Livingston, senior author of the study appearing in the October edition of Archives of Surgery. “This is a population that stands to gain the most from bariatric surgery.”
Dr. Livingston is chairman of gastrointestinal and endocrine surgery at UT Southwestern and chairman of the Veteran’s Administration Central Office Bariatric Surgery Work Group.
Nearly three quarters of hospitals offering bariatric surgery are considered low-volume facilities under the 125-case threshold, thereby leaving few centers available for impoverished populations.
Yet low-income patients, particularly those in rural areas, may not be able to travel to the limited number of high-volume centers due to costs such as gas, access to public transportation or personal vehicles, or health matters that limit their travel, Dr. Livingston said.
Such restrictions further limit medical expertise for morbidly obese patients by reducing the number of hospitals well-equipped and properly staffed to handle the special needs of these cases. “Regionalization results in the global reduction of experience in managing obese patients at a time when obesity is rapidly increasing in the population,” the study notes.
Researchers led by Dr. Livingston reviewed 51,000 records involving weight-loss surgeries carried out in nearly 750 U.S. hospitals over a three-year span (2001-2003).
Researchers found that statistical sampling methods used in the handful of studies favoring high-volume centers skewed results by amplifying a small number of excess deaths in very low-volume facilities. Databases used in the studies typically had sparse information on individual patients’ backgrounds. Accounting for the specific health risks of patients, however, often eliminates the advantages seen for high-volume centers, the analysis showed.
Low-volume centers tend to accept higher-risk patients, while high-volume centers gravitate toward more lower-risk patients, the researchers found. In either case, the overall risk was small, as the survival rate at low-income centers was 99.66 percent.
“Restricting cases to high-volume centers isn’t going to have a profound effect in limiting the number of deaths, but would have a profound effect in limiting accessibility to bariatric surgery,” Dr. Livingston said. “More likely, the surgeon’s cumulative experience and access to multidisciplinary teams of doctors available before, during and after surgery result in better outcomes.”
Rather than limiting procedures to high-volume centers, bariatric programs should be judged by risk-adjusted outcomes, such as the National Surgical Quality Improvement Program, he said.
That’s important because studies indicate that non-surgical therapies for morbidly obese patients are uniformly unsuccessful for sustained weight loss. In addition, despite increasing numbers of bariatric surgeries performed, they are still dwarfed by the eligible population. The Centers for Disease Control and Prevention estimates that nearly one-third of adult Americans – more than 60 million people – are obese, with nearly 5 percent of adults classified as extremely obese.
Bariatric surgeries, which are usually reserved for those more than 100 pounds overweight, can help not only with weight, but related health problems. Obese adults are at increased risk of diabetes, hypertension, stroke and even some cancers.
Weight-loss surgeries have become more common as obesity has increased, with more than 140,000 gastric bypass procedures now performed in the U.S. annually.
UT Southwestern’s Center for Minimally Invasive Surgery is one of only seven facilities in North America, and the only one in Texas, to be accredited by the American College of Surgeons. It has been named a Bariatric Surgery Center of Excellence by the American Society for Bariatric Surgery.

Beware Of Diet Rebound Effects

Each year at this time, almost 75% of people who are overweight begin a diet on their own. They do so either because they have seen a particular diet plan on the media, or a relative commented on it. However, only 20 percent of these people seek medical advice on which diets to follow, says the president of the Spanish Society for the Study of Obesity (SEED).
The expert believes that "in the summer holiday season people want shortcuts to diets that promise quick weight loss and resort to quick solutions. Some of the popular diets can cause hyperthyroidism or mesenteric vein thrombosis and at least the dreaded rebound effect on recovering the lost pounds, and sometimes more. "
This drop occurs because people abandon the enthusiasm ahead of time, causing undesirable effects on the body. Moreover, statistics provided by the SEED indicate that over 77% of people who start diets on a regular basis do so for cosmetic reasons while 38% do so for health reasons.
The fast diets include deficiencies of trace elements (proteins, vitamins and minerals), disorders such as anorexia or bulimia, or the appearance of negative psychological effects. "All are harmful and some have been fatal," says Moreno.
To recognize them, the so-called 'miracle diets' have three clear characteristics. They promises losing more than five pounds a month, ensure that it can be done without effort and that they don't pose health risks. The problem is that during the first month it is possible to get some results, but keeping them constant is the challenge. Yet, these "yo-yo" diet ads sometimes include quotes from celebrities that have allegedly been continuously successful.
Weight loss treatment should be personalized, and always under strict medical supervision.
According to Dr. M. Alemany, Professor of Biochemistry at the University of Barcelona, this "rebound effect" is very common and a great despair in those who suffer. It is coupled with a marked increase in obesity by improving the adaptability of the body against diets with lower energy content. "
"This ability to adapt," says Alemany, can itself be a cause for obesity, or a quantum leap from an overweight to obesity.
The "yo-yo" diets have very serious health risks. The break in the diet means the arrival of food in abundance. This in turns triggers insulin levels and thus enhances the conversion of glucose into fat. Professor Alemany says that "the danger is that it is chronic and has a rebound effect." This is due to the inconsistency in the monitoring of the diets.
Alemany compares it with the risks of indiscriminate use of antibiotics, allowing the proliferation of drug-resistant microbial strains. Dr. Alemany says that this problem could make "racial overweight roots to physiological " and cause a real obesity epidemic for which there is no immediate solution.