Unintentional weight loss
Poor management of type 1 diabetes mellitus, also known as insulin-dependent diabetes mellitus (IDDM), leads to an excessive amount of glucose and an insufficient amount of insulin in the bloodstream. This triggers the release of triglycerides from adipose (fat) tissue and catabolism (breakdown) of amino acids in muscle tissue. This results in a loss of both fat and lean mass, leading to a significant reduction in total body weight. Note that untreated type 1 diabetes mellitus will usually not produce weight loss, as these patients get acutely ill before they would have had time to lose weight.
Myriad additional scientific considerations are applicable to weight loss: 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.
Hormonal disruptions, such as an overactive thyroid (hyperthyroidism), may also exhibit as weight loss.
Recent research has shown fidgeting to result in significant weight loss.
Intentional weight loss
Intentional weight loss refers to the loss of total body mass in an effort to improve fitness, health, and/or appearance.
Therapeutic weightloss, in individuals who are overweight or obese, can decrease the likelihood of developing diseases such as diabetes, heart disease, high blood pressure, stroke, osteoarthritis, and certain types of cancer.
Attention to diet in particular can be extremely beneficial in reducing the impact of diabetes and other health risks of an expanding waist.
Weight loss occurs when an individual is in a state of negative energy balance. When the body is consuming more energy (i.e. in work and heat) than it is gaining (i.e. from food or other nutritional supplements), it will use stored reserves from fat or muscle, gradually leading to weight loss.
It is not uncommon for some people who are currently at their ideal body weight to seek additional weight loss in order to improve athletic performance, and/or meet required weight classification for participation in a sport. However, others may be driven by achieving a more attractive body image. Consequently, being underweight is associated with health risks such as difficulty fighting off infection, osteoporosis, decreased muscle strength, trouble regulating body temperature and even increased risk of death.
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 activity, generally in the form of exercise. Physicians will usually recommend that their overweight patients combine a reduction of processed and caloric content of the diet with an increase in physical activity.
Other methods of losing weight include use of drugs and supplements that decrease appetite, block fat absorption, or reduce stomach volume. Green tea and hoodia gordonii are often advertised as weight loss supplements. Medicines with herbs such as Fucus vesiculosus are popular. Weight Loss Coaching is rapidly growing in popularity in the United States, with the number of available coaches nearly doubling since 2000. Finally, surgery (i.e. bariatric surgery) may be used in more severe cases to artificially reduce the size of the stomach, thus limiting the intake of food energy.
A crash diet refers to willful nutritional restriction (except water) for more than 12 hours. The desired result is to have the body burn fat for energy with the goal of losing a significant amount of weight in a short time. However, the body reacts by preserving fat stores and burning lean muscle tissue, such that this is a poor strategy for intentional weight loss.
Crash dieting is not the same as intermittent fasting, in which the individual periodically abstains from food (e.g., every other day)
Weight loss industry
There is a substantial market for products which promise to make weight loss easier, quicker, cheaper, more reliable, or less painful. These include books, CDs, cremes, lotions, pills, rings and earrings, body wraps, body belts and other materials, not to mention 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.Between $33 billion and $55 billion is spent annually on weight loss products and services, including medical procedures and pharmaceuticals, with weight loss centers garnering between 6 percent and 12 percent of total annual expenditure. About 70 percent of Americans' dieting attempts are of a self-help nature. Although often short-lived, these diet fads are a positive trend for this sector as Americans ultimately turn to professionals to help them meet their weight loss goals