What Is Obesity?
Obesity is an excess proportion of total body fat. A person is considered obese when his or her weight is 20% or more above normal weight. The most common measure of obesity is the body mass index or BMI. A person is considered overweight if his or her BMI is between 25 and 29.9; a person is considered obese if his or her BMI is over 30.
"Morbid obesity" means that a person is either 50%-100% over normal weight, more than 100 pounds over normal weight, has a BMI of 40 or higher, or is sufficiently overweight to severely interfere with health or normal function.
What Causes Obesity?
Obesity occurs when a person consumes more calories than he or she burns. For many people this boils down to eating too much and exercising too little. But there are other factors that also play a role in obesity. These may include:
Age. As you get older, your body's ability to metabolize food slows down and you do not require as many calories to maintain your weight. This is why people note that they eat the same and do the same activities as they did when they were 20 years old, but at age 40, gain weight.
Gender. Women tend to be more overweight than men. Men have a higher resting metabolic rate (meaning they burn more energy at rest) than women, so men require more calories to maintain their body weight. Additionally, when women become postmenopausal, their metabolic rate decreases. That is partly why many women gain weight after menopause.
Genetics. Obesity (and thinness) tends to run in families. In a study of adults who were adopted as children, researchers found that participating adult weights were closer to their biological parents' weights than their adoptive parents'. The environment provided by the adoptive family apparently had less influence on the development of obesity than the person's genetic makeup. In fact, if your biological mother is heavy as an adult, there is approximately a 75% chance that you will be heavy. If your biological mother is thin, there is also a 75% chance that you will be thin. Nevertheless, people who feel that their genes have doomed them to a lifetime of obesity should take heart. Many people genetically predisposed to obesity do not become obese or are able to lose weight and keep it off.
Environmental factors. Although genes are an important factor in many cases of obesity, a person's environment also plays a significant role. Environmental factors include lifestyle behaviors such as what a person eats and how active he or she is.
Physical activity. Active individuals require more calories than less active ones to maintain their weight. Additionally, physical activity tends to decrease appetite in obese individuals while increasing the body's ability to preferentially metabolize fat as an energy source. Much of the increase in obesity in the last 20 years is thought to have resulted from the decreased level of daily physical activity.
Psychological factors. Psychological factors also influence eating habits and obesity. Many people eat in response to negative emotions such as boredom, sadness, or anger. People who have difficulty with weight management may be facing more emotional and psychological issues; about 30% of people who seek treatment for serious weight problems have difficulties with binge eating. During a binge-eating episode, people eat large amounts of food while feeling they can't control how much they are eating.
Illness. Although not as common as many believe, there are some illnesses that can cause obesity. These include hormone problems such as hypothyroidism (poorly acting thyroid slows metabolism), depression, and some rare diseases of the brain that can lead to overeating.
Medication. Certain drugs, such as steroids and some antidepressants, may cause excessive weight gain.
Emotional Aspects of Obesity
One of the most painful aspects of obesity may be the emotional suffering it causes. American society places great emphasis on physical appearance, often equating attractiveness with slimness or muscularity. In addition, many people wrongly stereotype obese people as gluttonous, lazy, or both. However, more and more evidence contradicts this assumption. Obese people often face prejudice or discrimination at work, at school, while looking for a job, and in social situations. Feelings of rejection, shame, or depression are common.
When to Seek Help for Obesity
You should call your doctor if you are having emotional or psychological issues related to your obesity, need help losing weight, or if you fall into either of the following categories.
If your BMI is 30 or greater, you're considered obese. You should talk to your doctor about losing weight since you are at high risk of having health problems.
If you have an "apple shape" -- a so-called, "potbelly" or "spare tire" -- you carry more fat in and around your abdominal organs. Fat deposited primarily around your middle increases your risk of many of the serious conditions associated with obesity. Women's waist measurement should fall below 35 inches. Men's should be less than 40 inches. If you have a large waist circumference, talk to your doctor about how you can lose weight.
Obesity Epidemic "Astronomical"
The prognosis for the nation is bad and getting worse as obesity takes its toll on the health of adults and children alike.
By R. Morgan Griffin WebMD
One of the biggest health stories of the year has been the rise in obesity among both adults and children in the U.S. We've all heard so much about the "obesity epidemic" that it's easy to think the story is being blown out of proportion. After all, people putting on a few pounds may not seem to warrant the proclamation of a national emergency.
But while obesity may not be the Black Death, it is a severe public health crisis. Experts agree that as more and more Obese Children become obese Adults, the diseases associated with obesity, such as Heart Disease, Cancer, and especially Diabetes will surge. That will mean a lot of sick people.
According to Marion Nestle, PhD, MPH, chair of the Department of Nutrition and food studies at New York University, the costs of these illnesses will be "astronomical."
James O. Hill, PhD, agrees. Hill, director of the Center for Human Nutrition at the University of Colorado Health Sciences Center, claims that at the rate we're going, obesity-related diabetes alone "will break the bank of our healthcare system." So one has to wonder how obesity got so out of control that we reached this crisis. And more importantly, how do we stop it?
So what's causing the epidemic? Not surprisingly, everyone agrees that it stems from two things: eating too much and exercising too little. The differences are in the specifics.
Although people may toss around the idea of genetics in obesity, genes can't really explain what's happening, Hill says. While a person may have a genetic predisposition toward a certain body type, the fact that each succeeding generation is heavier than the last proves that changes in our environment are playing the key role.
Hill believes the culprit may be a decrease in our physical activity, arguing that because of shifts in how we live and work, we don't get as much exercise as previous generations did.
Nestle agrees that exercise is important, but she lays more stress on eating habits. In her book Food Politics: How the Food Industry Influences Nutrition and Health, Nestle argues that recommendations about healthy eating are overwhelmed by the hundreds of billions of dollars worth of advertising for junk foods that we're subjected to at home and even in public schools. And as fast food companies and chains compete with one another by increasing portion sizes, our waists are increasing proportionately.
Despite the new attention paid to obesity by doctors, researchers, and the media, no discernable progress has been made in fighting obesity. According to most experts, it looks almost certain that obesity will get worse before it gets better.
Cynthia Ogden, PhD, a CDC epidemiologist, published the results of a study of weight in the United States that she conducted with other experts. The results were startling: 31% of adults are obese and 15% of children and teenagers age 6-19 are overweight. The proportion of obese people has been growing steadily for the last few decades. Although Ogden stresses that obesity is a problem for all groups and genders, it is particularly severe among certain ethnic groups. For instance, 50% of all non-Hispanic black women are obese.
Did Ogden see anything promising in the results of the study about obesity in the U.S.? "I didn't see any hopeful signs," she says.
Genomics and Health
Behavior, environment, and genetic factors all have a role in causing people to be overweight and obese Obesity results from the energy imbalance that occurs when a person consumes more calories than their body burns. Obesity is a serious public health problem because it is associated with some of the leading causes of death in the U.S. and worldwide, including diabetes, heart disease, stroke, and some types of cancer.
Do Genes Have a Role in Obesity?
In recent decades, obesity has reached epidemic proportions in populations whose environments promote physical inactivity and increased consumption of high-calorie foods. However, not all people living in such environments will become obese, nor will all obese people have the same body fat distribution or suffer the same health problems. These differences can be seen in groups of people with the same racial or ethnic background and even within families. Genetic changes in human populations occur too slowly to be responsible for the obesity epidemic. Nevertheless, the variation in how people respond to the same environment suggests that genes do play a role in the development of obesity.
How Could Genes Influence Obesity?
Genes give the body instructions for responding to changes in its environment. Studies of resemblances and differences among family members, twins, and adoptees offer indirect scientific evidence that a sizable portion of the variation in weight among adults is due to genetic factors. Other studies have compared obese and non-obese people for variation in genes that could influence behaviors (such as a drive to overeat, or a tendency to be sedentary) or metabolism (such as a diminished capacity to use dietary fats as fuel, or an increased tendency to store body fat). These studies have identified variants in several genes that may contribute to obesity by increasing hunger and food intake.
Rarely, a clear pattern of inherited obesity within a family is caused by a specific variant of a single gene (monogenic obesity). Most obesity, however, probably results from complex interactions among multiple genes and environmental factors that remain poorly understood (multifactorial obesity).
The "Thrifty Genotype" Hypothesis
Any explanation of the obesity epidemic has to consider both genetics and the environment. One explanation that is often cited is the mismatch between today’s environment and "energy-thrifty genes" that multiplied in the distant past, when food sources were unpredictable. In other words, according to the "thrifty genotype" hypothesis, the same genes that helped our ancestors survive occasional famines are now being challenged by environments in which food is plentiful year round.
Can Public Health Genomics Help?
Currently, genetic tests are not useful for guiding personal diet or physical activity plans. Research on genetic variation that affects response to changes in diet and physical activity is still at an early stage. Doing a better job of explaining obesity in terms of genes and environment factors could help encourage people who are trying to reach and maintain a healthy weight.
What about Family History?
Health care practitioners routinely collect family health history to help identify people at high risk of obesity-related diseases such as diabetes, cardiovascular diseases, and some forms of cancer. Family health history reflects the effects of shared genetics and environment among close relatives. Families can’t change their genes but they can change the family environment to encourage healthy eating habits and physical activity. Those changes can improve the health of family members—and improve the family health history of the next generation.
How Can You Tell If You or Your Family Members Are Overweight?
Most health care practitioners use the Body Mass Index (BMI) to determine whether a person is overweight. Check your Body Mass Index with a BMI calculator.
Bouchard C. The biological predisposition to obesity: beyond the thrifty genotype scenario. Int J Obes 2007; 31:1337-9.
Bouchard C. Defining the genetic architecture of the predisposition to obesity: a challenging but not insurmountable task. Am J Clin Nutr 2010; 91:5-6.
Choquet H, Meyre D. Genetics of obesity: what have we learned? Curr Genomics. 2011;12:169-79.
MASTER SWITCH GENE FOR OBESITY AND DIABETES DISCOVERED
A team of researchers, led by King's College London and the University of Oxford, have found that a gene linked to type 2 diabetes and cholesterol levels is in fact a 'master regulator' gene, which controls the behaviour of other genes found within fat in the body. As fat plays a key role in susceptibility to metabolic diseases such as obesity, heart disease and diabetes, this study highlights the regulatory gene as a possible target for future treatments to fight these diseases.
Published today in Nature Genetics, the study was one part of a large multi-national collaboration funded by the Wellcome Trust, known as the MuTHER study. It involves researchers from King's College London, University of Oxford, The Wellcome Trust Sanger Institute, and the University of Geneva. DeCODE Genetics also contributed to the results reported in this paper. It was already known that the KLF14 gene is linked to type 2 diabetes and cholesterol levels but, until now, how it did this and the role it played in controlling other genes located further away on the genome was unknown.
The researchers examined over 20,000 genes in subcutaneous fat biopsies from 800 UK female twin volunteers. They found an association between the KLF14 gene and the expression levels of multiple distant genes found in fat tissue, which means it acts as a master switch to control these genes. This was then confirmed in a further independent sample of 600 subcutaneous fat biopsies from Icelandic subjects. These other genes found to be controlled by KLF14 are in fact linked to a range of metabolic traits, including body-mass index (obesity), cholesterol, insulin and glucose levels, highlighting the interconnectedness of metabolic traits.
The KLF14 gene is special in that its activity is inherited from the mother. Each person inherits a set of all genes from both parents. But in this case, the copy of KLF14 from the father is switched off, meaning that the copy from the mother is the active gene – a process called imprinting. Moreover, the ability of KLF14 to control other genes was entirely dependent on the copy of KLF14 inherited from the mother – the copy inherited from the father had no effect.
Professor Tim Spector from the Department of Twin Research at King's, who led the MuTHER project, said: 'This is the first major study that shows how small changes in one master regulator gene can cause a cascade of other metabolic effects in other genes. This has great therapeutic potential particularly as by studying large detailed populations such as the twins we hope to find more of these regulators.'
Professor Mark McCarthy from the University of Oxford, who co-led the study, said: 'KLF14 seems to act as a master switch controlling processes that connect changes in the behaviour of subcutaneous fat to disturbances in muscle and liver that contribute to diabetes and other conditions. We are working hard right now to understand these processes and how we can use this information to improve treatment of these conditions.'
Overweight and Obesity
American society has become 'obesogenic,' characterized by environments that promote increased food intake, nonhealthful foods, and physical inactivity. Policy and environmental change initiatives that make healthy choices in nutrition and physical activity available, affordable, and easy will likely prove most effective in combating obesity.
The Division of Nutrition, Physical Activity, and Obesity (DNPAO) is working to reduce obesity and obesity-related conditions through state programs, technical assistance and training, leadership, surveillance and research, intervention development and evaluation, translation of practice-based evidence and research findings, and partnership development.
ARE OUR CHILDREN GETTING FAT TOO ??
Achieving and maintaining a healthy weight isn't just about a "diet" or "program."
It is part of an ongoing lifestyle that you can adopt now and stay with for years to come.
Obesity is a risk factor for health conditions such as diabetes and is associated
with problems such as poor self-esteem.
The good news is that schools can help students and staff adopt healthy eating
and physical activity behaviors that are the keys to preventing obesity
Obesity Documentary Examines Why
“This Generation of Young People May be the First to Live Shorter Lives than Their Parents”
Salt Lake City, UTAH
ShineBox Media Productions is proud to announce this week the nomination of its new film, “Killer at Large”,
For the prestigious Gold Medal Documentary Film award by the International Filmmaker Festival. “Killer at Large” is the only American film represented in this year’s competition at the annual festival – held in the South of England. Directed by Steven Greenstreet, “Killer at Large” examines the startling details of the American obesity epidemic and why this issue has crossed from a public health crisis to a national security issue. When asked in the film what the most pressing issue facing America today, former Surgeon General Richard Carmona responded, “Obesity. Because obesity is a terror within. It is destroying our society from within and unless we do something about it, the magnitude of the dilemma will dwarf 9/11 or any other terrorist event you can point out. Where will our soldiers, sailors, and airmen come from? Where will our police and firemen come from if the youngsters today are on a trajectory that says they will be obese?” While the issue of obesity has simmered to the forefront of the mainstream media’s attention, “Killer at Large” picks up where the reality shows leave off, moving far beyond individual struggles and extreme diets to deeply dissect this epic struggle that predates human history.
With many experts in the field of childhood obesity declaring that this may be the first generation of children to have a shorter life expectancy than their parents, “Killer at Large” provides an intricate and sobering perspective on the most pressing health issue of our time. It also serves as a call to arms for concerned parents, school districts, employers, and entire communities who have empowered themselves to take a stand and reverse this deadly trend – which is poised to cripple our nation’s health care system and bankrupt our economy within the next 20 years. Sadly, the solutions to these problems that have been coming from the government and the industries who share culpability in this problem range from the absurd (industry should regulate itself) to the obvious (consumers should simply be exercising more.) “Killer at Large” details why this approach not only doesn’t help, but is actually making the problem worse. According to the National Institute of Diabetes and Digestive and Kidney Diseases, obesity and its related illnesses are estimated to kill over 100,000 Americans a year and cost taxpayers $117 billion in 2002 alone. The film features interviews and footage of numerous public figures discussing the politics and causes and effects of obesity, including former President Bill Clinton, consumer advocate Ralph Nader, filmmaker Neil LaBute, Senator Tom Harkin, Senator Sam Brownback, Governor Mike Huckabee, and a number of bestselling authors such as Michael Pollan, Chef Ann Cooper, and Dr. Brian Wansink among many others. For more information about the project and links to more obesity information, please visit www.KilleratLarge.com.
“Killer at Large” has been in research and production since late 2006 and is directed by Steven Greenstreet. In 2005, Greenstreet directed the award-winning documentary “This Divided State” which chronicled the furor over Utah Valley State College’s decision to bring Michael Moore to speak on campus in the days before the divisive 2004 presidential election. Greenstreet and his producing partners Bryan Young and Elias Pate have spent the last year preparing this important, issues-oreiented documentary for a wide 2008 release. Greenstreet, Young, and Pate are available for interviews, media appearances, and other press related functions in relation to the Obesity epidemic and independent filmmaking.