Some genetic factors have been proved to play a key role in the pathogenesis of obesity or enhance susceptibility to its pathogenesis. Prader-Willi Syndrome, Ahlstrom’s syndrome and Cohen’s syndrome are some rare medical conditions in which various genetic determinants have been associated with the development of obesity.
As of today, four genes have been identified in which mutations cause abnormal weight gain (obesity) in animals and some of these are also suspected to be involved in humans. The most important and widely studied leptin gene (which is adipose tissue specific) in its mutated form, is found to be responsible for obesity in rats. This gene normally expresses leptin (a hormone) secreted from fat cells. Leptin levels in fat cells and in circulation are found to be increased in animal and human obese subjects. Splicing defects in the leptin receptor are responsible for increased obesity in mouse experiments. One such defect causes Retinitis Pigmentosa and obesity in mice just like the Lawrence-Moon-Biedl syndrome of humans. Some other genes like beta3-adrenergic receptor, Tumor Necrosis Factor-α (TNF- α) and lipoprotein lipase gene have also been studied and implicated in the development of human obesity.
Genetic susceptibility to obesity and body weight distribution has been studied extensively. Around 40% of the variation in body fat is considered as genetically determined. But pathogenic development of obesity is believed to be the result of complex interaction of many genetic variables. However contribution of genetic factors in the overall disease burden is rather small.
Obesity is medically defined as a state of excessive adipose tissue (fat) deposition in the body or in other words a person is considered as obese when a large mass of fat accumulates in specific parts of the body. It is to be noted however that “obesity” and “overweight” are not synonymous terms and does not imply the same thing always. For example an overweight person (due to large muscle mass) cannot be considered as obese. Historically being obese was considered as a sign of well being and health in ancient times. But this condition has transformed into one of the most serious public health problem worldwide today. According to NHANES data, over 65% of American adults (age 20 years) are overweight (defined as having BMI >25). Percentage of population having excessive obesity (BMI > 40, also called morbid or super obesity) is also increasing rapidly (currently at around 5%).
HOW OBESITY IS DIAGNOSED AND CLASSIFIED?
BMI (Body Mass Index) is the most common method to define and measure obesity. BMI is calculated by dividing body weight (in Kg) by square of height (measured in meters). Although there are many ethnic and regional differences are considered in ascertaining the normal range of BMI, still the widely accepted one is 18-25 Kg/meter-squre. BMI more than 25 denotes obesity and more than 30 is variously called as extreme obesity, super obesity or morbid obesity. Many large-scale epidemiological studies indicate that morbidity/mortality from metabolic, cardiovascular and other causes steeply rise when BMI is more than 30. Anthropometry (skin-fold thickness), densitometry (underwater weight), CT scan (Computed Tomography), MRI (Magnetic Resonance Imaging) and electrical impedance studies are some other specialized measures to define and quantify obesity.
Besides BMI, distribution of fat in different anatomic locations is also important in the long term outcome (morbidity and mortality) of obesity. For example, intra-abdominal and abdominal subcutaneous (below skin) fat is more dangerous than the fat present at hips or elsewhere. Many complications of obesity, such as insulin resistance, diabetes, hypertension, and hyper-lipidemia etc are linked more strongly to intra-abdominal and/or upper body fat than to overall adiposity.
WHAT CAUSES OBESITY?
There are many causes (or risk factors rather) of obesity – a mix of nutritional imbalance (excessive food intake), genetic predisposition, sedentary life style and some still unknown factors, all contribute to the disease development.
HOW TO TREAT OBESITY?
Weight loss therapies, dietary restrictions and regular physical exercise are the main approaches to obesity treatment. Other treatment modalities include liposuction and other surgical procedures, genetic and psychiatric counseling etc. All these and other weight loss therapies will be discussed in detail later on here at WLB. So stay tuned
Obesity is now so widespread in developed countries (especially US and Europe) that it’s been unofficially declared as an epidemic by health agencies. The scenario is getting worse as obesity (and associated diseases) is spreading even faster in many developing countries as well (like India and China etc) due to drastic improvement in economic and health care infrastructure. Thus it is expected to be declared as a “pandemic” soon. Controlled weight-loss (also called “weight management”) essentially forms the core of every obesity treatment plan. “Losing weight” therefore has never been so important. Another main reason behind interest in “weight loss” plans is the eternal desire of human beings to have that elusive “perfect body shape”.
Interestingly very few health subjects are as clearly defined as “weight loss”, still vast majority of peoples believe it be one of the most difficult target to achieve. There are many factors that strengthen this thinking for example lack of will power to adhere to a weight loss plan or in other words failure to suppress the “drive to eat” and vested interests of MNC Pharma giants which are making millions by selling ineffective medicines.
This blog is a humble effort to guide you through the tortuous paths of “weight-loss” mirage. At http://www.optimalnutritions.com we strive to provide you enough authentic content about “weight loss” so that you can yourself answer the ever enigmatic question “How to actually lose weight?”. It would be our endeavor to include only the most up to date content obtained from globally recognized, reputed and authentic sources (international research journals, text books, expert opinions etc). Besides all the modern sources we will also include ethnic and local practices that are found to be effective in losing weight.
http://www.optimalnutritions.com/obesity-factsObesity Facts- Shocking Life Risk other Causes of ObesityHealthSome genetic factors have been proved to play a key role in the pathogenesis of obesity or enhance susceptibility to its pathogenesis. Prader-Willi Syndrome, Ahlstrom’s syndrome and Cohen’s syndrome are some rare medical conditions in which various genetic determinants have been associated with the development of obesity. As of today, four genes have been...admin email@example.comAdministratorBlackCore Edge Max