Obesity

Friedman and colleagues discovered leptin (from the Greek word leptos, meaning thin) in 1994 and ushered in an explosion of research and a great increase in knowledge about the regulation of the human feeding and satiation cycle. Leptin is a 16-kD protein produced predominantly in white subcutaneous adipose tissue and, to a lesser extent, in […] Read More

Smell plays an important role in feeding behavior. Differences in the odor detection threshold (i.e., the lowest concentration of a substance detectable by the human olfactory sense) were found in a study that measured thresholds in 8 lean, fasted individuals before and during a 2-hour hyperinsulinemic-euglycemic insulin clamp. Increased insulin led to reduced smelling capacity, […] Read More

In addition to neurotransmitters and neurogenic signals, many hormones affect appetite and food intake. Endocannabinoids, through their effects on endocannabinoid receptors, increase appetite, enhance nutrient absorption, and stimulate lipogenesis. Melanocortin hormone, through its effects on various melanocortin receptors, modifies appetite. Several gut hormones play significant roles in inducing satiety, including glucagon-like peptide-1 (GLP-1), neuropeptide YY […] Read More

Critical enzymes involved in adipocyte metabolism and function include the following: Endothelial-derived lipoprotein lipase – Lipid storage; Hormone-sensitive lipase – Lipid elaboration and release from adipocyte depots; Acyl-coenzyme A (acyl-CoA) synthetases – Fatty acid synthesis. In addition, a cascade of enzymes is involved in beta-oxidation and fatty acid metabolism. The ongoing flurry of an investigation […] Read More

Proinflammatory products of the adipocyte include the following: Tumor necrosis factor-alpha; Interleukin 6; Monocyte chemo attractant protein–1 (MCP-1). Other adipocyte products include the following : Lipotransin; Plasminogen activator inhibitor-1 (PAI-1) – Associated with cardiovascular risk; Adipocyte lipid-binding protein; Acyl-stimulation protein; Prostaglandins; Adipsin; Perilipins; Lactate; Leptin – Appetite regulator; Adiponectin – With a major role in […] Read More

The adipocyte is increasingly found to be a complex and metabolically active cell. At present, the adipocyte is perceived as an active endocrine gland producing several peptides and metabolites that may be relevant to the control of body weight; these are being studied intensively. Many of the adipocytokines secreted by adipocytes are proinflammatory or play […] Read More

The adipocyte, which is the cellular basis for obesity, may be increased in size or number in obese persons. Hypertrophic obesity, characterized by enlarged fat cells, is typical of android abdominal obesity. Hypercellular obesity is more variable than hypertrophic obesity; it typically occurs in persons who develop obesity in childhood or adolescence, but it is […] Read More

A study by Cameron et al indicated that in the United States between 2013 and 2016, obesity was responsible for the development of new-onset diabetes in 41% of adults. The highest attributable rate of obesity-related diabetes was among non-Hispanic White women (53%); non-Hispanic Black men demonstrated the lowest rate, with the attributable fraction being 30%. […] Read More

Overweight and obese individuals are at increased risk for the following health conditions: Metabolic syndrome; Type 2 diabetes; Hypertension; Dyslipidemia; Coronary heart disease; Osteoarthritis; Stroke; Depression; Non-alcoholic fatty liver disease (NAFLD); Infertility (women) and erectile dysfunction (men); Risk of stillbirth; Gall bladder disease; Obstructive sleep apnea; Gastroesophageal reflux disease (GERD); Some cancers (endometrial, breast, and […] Read More

Sleep duration of fewer than 5 hours or more than 8 hours was associated with increased visceral and subcutaneous body fat. This association relates mostly to decreased leptin hormone and increased ghrelin hormone levels. Read More