 | This article possibly contains original research .(December 2014) |
| Normal weight obesity | |
|---|---|
| Specialty | Endocrinology |
| Treatment | Diet, exercise |
Normal weight obesity (colloquially, being "skinny fat") is the condition of having normal body weight, but with a high body fat percentage, leading to some of the same health risks as obesity.
The term "metabolically obese normal weight" (MONW) refers to people with normal weight and body mass index (BMI), who display some metabolic characteristics which increase the risk of developing metabolic syndrome in the same way as obesity. People with MONW have excess visceral fat, and are predisposed to hyperinsulinemia, insulin-resistance and thus predisposition to type 2 diabetes, hypertriglyceridemia, hypertension and premature coronary heart disease or cardiovascular disease. [1] The BMI does not capture information about percentage body fat (PBF), which is a better predictor of risk due to obesity. [2] [3] [4] [5] Some studies have suggested that the main factor which explains the metabolic abnormalities in MONW individuals is fat distribution. On the basis of these studies, a scoring method has been proposed to identify MONW individuals, based on the presence of associated diseases or biochemical abnormalities related to insulin resistance. [6]
In 2008, the first prevalence of US adults above 20 years was published, based on the National Health and Nutrition Examination Surveys from 1999 to 2004, finding that 24% of normal-weight adults were metabolically abnormal; on the other hand 49% of overweight adults and 68% of obese adults were metabolically abnormal. [7] [ clarification needed ] An analysis from an earlier NHANES from 1988 to 1994 found people with NWO had a four-fold higher frequency of metabolic syndrome compared with the low body fat group. [8] In 2015 the overall presence in the general worldwide population was suggested to be about 20%, with European populations having the highest rate of MONW. Patterns were subject to and also influenced by gender, age, smoking, alcohol use, and region. [9]
As of 2018, optimal treatment is unknown. [10] A 1998 study suggested that energy restriction and weight loss, for example a 4- to 12-week period of diet and exercise was beneficial. [1] A small study of 11 Asians with MONW published June 2018 found that moderate weight loss through dieting reduced their cardiometabolic risk per improved body composition, lipid profile, and insulin sensitivity. [10]
Magnesium supplementation orally has been shown to improve blood pressure and metabolic profile for those listed as MONW. [11]
Metabolic syndrome is a clustering of at least three of the following five medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL).
Insulin resistance (IR) is a pathological condition in which cells in insulin-sensitive tissues in the body fail to respond normally to the hormone insulin or downregulate insulin receptors in response to hyperinsulinemia.
Abdominal obesity, also known as central obesity and truncal obesity, is the human condition of an excessive concentration of visceral fat around the stomach and abdomen to such an extent that it is likely to harm its bearer's health. Abdominal obesity has been strongly linked to cardiovascular disease, Alzheimer's disease, and other metabolic and vascular diseases.
Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it can potentially have negative effects on health. People are classified as obese when their body mass index (BMI)—a person's weight divided by the square of the person's height—is over 30 kg/m2; the range 25–30 kg/m2 is defined as overweight. Some East Asian countries use lower values to calculate obesity. Obesity is a major cause of disability and is correlated with various diseases and conditions, particularly cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis.
Adipose tissue is a loose connective tissue composed mostly of adipocytes. It also contains the stromal vascular fraction (SVF) of cells including preadipocytes, fibroblasts, vascular endothelial cells and a variety of immune cells such as adipose tissue macrophages. Its main role is to store energy in the form of lipids, although it also cushions and insulates the body.
Adipocytes, also known as lipocytes and fat cells, are the cells that primarily compose adipose tissue, specialized in storing energy as fat. Adipocytes are derived from mesenchymal stem cells which give rise to adipocytes through adipogenesis. In cell culture, adipocyte progenitors can also form osteoblasts, myocytes and other cell types.
Adiponectin is a protein hormone and adipokine, which is involved in regulating glucose levels and fatty acid breakdown. In humans, it is encoded by the ADIPOQ gene and is produced primarily in adipose tissue, but also in muscle and even in the brain.
Weight gain is an increase in body weight. This can involve an increase in muscle mass, fat deposits, excess fluids such as water or other factors. Weight gain can be a symptom of a serious medical condition.
Prediabetes is a component of metabolic syndrome and is characterized by elevated blood sugar levels that fall below the threshold to diagnose diabetes mellitus. It usually does not cause symptoms but people with prediabetes often have obesity, dyslipidemia with high triglycerides and/or low HDL cholesterol, and hypertension. It is also associated with increased risk for cardiovascular disease (CVD). Prediabetes is more accurately considered an early stage of diabetes as health complications associated with type 2 diabetes often occur before the diagnosis of diabetes.
Being overweight is having more body fat than is optimally healthy. Being overweight is especially common where food supplies are plentiful and lifestyles are sedentary.
Sarcopenic obesity is a combination of two disease states, sarcopenia and obesity. Sarcopenia is the muscle mass/strength/physical function loss associated with increased age, and obesity is based off a weight to height ratio or body mass index (BMI) that is characterized by high body fat or being overweight.
Obesity classification is a ranking of obesity, the medical condition in which excess body fat has accumulated to the extent that it has an adverse effect on health. The World Health Organization (WHO) classifies obesity by body mass index (BMI). BMI is further evaluated in terms of fat distribution via the waist–hip ratio and total cardiovascular risk factors. In children, a healthy weight varies with sex and age, and obesity determination is in relation to a historical normal group.
A person's waist-to-height ratio – occasionally written WHtR – or called waist-to-stature ratio (WSR), is defined as their waist circumference divided by their height, both measured in the same units. It is used as a predictor of obesity-related cardiovascular disease. The WHtR is a measure of the distribution of body fat. Higher values of WHtR indicate higher risk of obesity-related cardiovascular diseases; it is correlated with abdominal obesity.
Sleep is important in regulating metabolism. Mammalian sleep can be sub-divided into two distinct phases - REM and non-REM (NREM) sleep. In humans and cats, NREM sleep has four stages, where the third and fourth stages are considered slow-wave sleep (SWS). SWS is considered deep sleep, when metabolism is least active.
A number of lifestyle factors are known to be important to the development of type 2 diabetes including: obesity, physical activity, diet, stress, and urbanization. Excess body fat underlies 64% of cases of diabetes in men and 77% of cases in women. A number of dietary factors such as sugar sweetened drinks and the type of fat in the diet appear to play a role.
TOFI (thin-outside-fat-inside) is used to describe lean individuals with a disproportionate amount of fat stored in their abdomen. The figure to illustrate this shows two men, both 35 years old, with a BMI of 25 kg/m2. Despite their similar size, the TOFI had 5.86 litres of internal fat, whilst the healthy control had only 1.65 litres.
This article provides a global overview of the current trends and distribution of metabolic syndrome. Metabolic syndrome refers to a cluster of related risk factors for cardiovascular disease that includes abdominal obesity, diabetes, hypertension, and elevated cholesterol.
Diabetes mellitus, often known simply as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough insulin, or the cells of the body becoming unresponsive to the hormone's effects. Classic symptoms include thirst, polyuria, weight loss, and blurred vision. If left untreated, the disease can lead to various health complications, including disorders of the cardiovascular system, eye, kidney, and nerves. Diabetes accounts for approximately 4.2 million deaths every year, with an estimated 1.5 million caused by either untreated or poorly treated diabetes.
Metabolically healthy obesity (MHO) is a disputed medical condition characterized by obesity which does not produce metabolic complications.
Obesity is defined as an abnormal accumulation of body fat, usually 20% or more over an individual's ideal body weight. This is often described as a body mass index (BMI) over 30. However, BMI does not account for whether the excess weight is fat or muscle, and is not a measure of body composition. For most people, however, BMI is an indication used worldwide to estimate nutritional status. Obesity is usually the result of consuming more calories than the body needs and not expending that energy by doing exercise. There are genetic causes and hormonal disorders that cause people to gain significant amounts of weight but this is rare. People in the obese category are much more likely to suffer from fertility problems than people of normal healthy weight.
