Weight loss
Weight loss, in the context of medicine or health or physical fitness, is a reduction of the total body weight, due to a mean loss of fluid, body fat or adipose tissue and/or lean mass, namely bone mineral deposits, muscle, tendon and other connective tissue.
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Unintentional weight loss
A significant loss of total body weight is a serious, chronic illness. Substantial, unintentional weight loss is a symptom of acute or chronic illness, especially if other evidence is present.
Weight loss, for example, accompanied by insatiable thirst and hunger and fatigue may indicate diabetes mellitus, a chronic disease characterized by an abnormal accumulation of carbohydrates in the bloodstream due to insufficient production of insulin, a hormone produced in the pancreas that, when secreted into the bloodstream, permits cellular metabolism and utilization of glucose.
Poor management of insulin-dependent diabetes mellitus (IDDM), also known as diabetes mellitus type I, leads to an excessive amount of glucose and an insufficient amount of insulin in the bloodstream. This triggers the release of triglycerides from adipose tissue and catabolism of amino acids in muscle tissue. This results in a loss of both fat and lean mass, predisposing a significant reduction in total body weight.
A myriad of additional scientific considerations are applicable to weight loss, including but not limited to physiological and exercise sciences, nutrition science, behavioral sciences, and other sciences.
One area involves the science of bioenergetics including biochemical and physiological energy production and utilization systems, that is frequently evidence of diabetes, and ketone bodies, acetone particles occurring in body fluids and tissues involved in acidosis, also known as ketosis, somewhat common in severe diabetes.
In addition to weight loss due to a reduction in fat and lean mass, illnesses such as diabetes, certain medications, lack of fluid intake and other factors can trigger fluid loss. And fluid loss in addition to a reduction in fat and lean mass exacerbates the risk for cachexia.
Infections such as HIV may alter metabolism, leading to weight loss.[1]
Hormonal disruptions, such as an overactive thyroid (hyperthyroidism) , may also exhibit as weight loss.[2]
Intentional weight loss
Weight loss may refer to the loss of total body mass in an effort to improve fitness, health, or appearance.
Therapeutic weight loss, in individuals who are overweight, can decrease the likelihood of developing diseases such as diabetes [3]. Overweight and obese individuals face a greater risk of health conditions such as type 2 diabetes, heart disease, high blood pressure, and osteoarthritis [4]. For healthy weight loss, a physician should be consulted to develop a weight loss plan that is tailored to the individual.
Weight loss occurs when an individual is in a state of negative energy balance. When the human body is spending more energy in work and heat than it is gaining from food or other nutritional supplements, it will catabolise stored reserves of fat or muscle.
It is not uncommon for people who are already at a medically healthy weight to intentionally lose weight. In some cases it is with the goal of improving athletic performance or to meet weight classifications in a sport. In other cases, the goal is to attain a more attractively shaped body. Being underweight is associated with health risks. Health problems can include fighting off infection, osteoporosis, decreased muscle strength, trouble regulating body temperature and even increased risk of death.[5]
Therapeutic weight loss techniques
The least intrusive weight loss methods, and those most often recommended by physicians, are adjustments to eating patterns and increased physical exercise. Usually, health professionals will recommend that their overweight patients combine a reduction of the caloric content of the diet with an increase in physical activity.[6]Other methods of losing weight include use of drugs and supplements that decrease appetite, block fat absorption, or reduce stomach volume. Surgery is another method. Bariatric surgery artificially reduces the size of the stomach, limiting the intake of food energy. Some of these treatments may have serious side-effects.
Weight loss industry
There is a huge market for products which promise to make weight loss easier, quicker, cheaper, more reliable, or less painful. These include books, CDs, and other materials, fitness centers, personal coaches, weight loss groups and food products and supplements. US residents in 1992 spent an estimated $30 billion a year on all types of diet programs and products, including diet foods and drinks.
Types of dieting
There are several kinds of diets:
- Weight-loss diets restrict the intake of specific foods, or food in general, to reduce body weight. What works to reduce body weight for one person will not necessarily work for another, due to metabolic differences and lifestyle factors. Also, for a variety of reasons, most people find it very difficult to maintain significant weight loss over time. There is some thought that losing weight quickly may actually make it more difficult to maintain the loss over time. It is also possible that cutting calorie intake too low slows or prevents weight loss. The National Institutes of Health notes that the commonly recommended program of reduced caloric intake along with increased physical activity has a failure rate of 98%.
- Many professional athletes impose weight-gain diets on themselves. American football players may try to "bulk up" through weight-gain diets in order to gain an advantage on the field with a higher mass.
- Individuals who are underweight, such as those recovering from anorexia nervosa or from starvation, may undergo weight-gain diets which, unlike those of athletes, has the goal of restoring normal levels of body fat, muscle, and stores of essential nutrients.
Many people in the acting industry may choose to lose or gain weight depending on the role they're given.
In children and young adults
Receiving adequate nutrition through a well-balanced diet is critical during childhood and adolescence. Unless a doctor says otherwise, low-carb, low-fat, or other specialty diets for children who are not heavily obese are unhealthy because they deprive the body of the building blocks of cells (namely energy and lipids in the above examples).
It is especially notable that, as more cultures scrutinize their diets, many improperly educated mothers consider putting their children on restricted diets that actually do more harm than good. This is extremely deleterious to a young child's health because a full and balanced diet (fats, carbohydrates, protein, vitamins, minerals, fiber, etc.) is needed for growth. Vegetarian diets can work for children as long as all needed nutrients are received. A doctor should be consulted before putting any child on a specialized diet.
Research also shows that putting children on diet foods can be harmful. The brain is unable to learn how to correlate taste with nutritional value, which is why such children may consistently overeat later in life despite adequate nutritional intake.
