Resting Metabolic Rate and RBP4

Genetic research of obesity was partly successful in establishing obesity in model organisms – rodents where obesity occurs spontaneously together with other pathological aspects (insulin resistance, …). The main cause of monogenic obesity in these model organisms are common mutations always present in only one gene. Results of research on model organisms allowed us to understand biological mechanisms of calorie intake and regulation and maintenance of body weight. The most important insight into obesity was achieved in 1994 after discovery of ob gene encoding for leptin. In two years period, using screening method, candidate homologous genes, selected on genetic study basis on mice, another five genes were identified. Mutations on these genes were found to be the cause of autosomal recessive or dominant monogenic obesity. Products of these genes are leptin and its receptor, proopiomelanocortin (POMC) melanocortin receptor 4 (MC4R) and

A person’s genetic make up has a significant influence on whether the person will become obese or not. If both parents are obese, the likelihood that their children may end up being obese too is higher compared to a situation where neither of the parents is obese or where only one of the parents is obese. This is particularly so because genetics influence the way the body stores energy and how energy is used. This can be seen in the differences that have recorded in the basal metabolic rates (BMR) among groups of people who differ by age, gender and the make up of their bodies. People who have a low metabolic rate have a higher risk of becoming overweight. The genetic similarities shared by members of one family can explain why people who come form certain families end up being overweight (DeBruyne, Pinna

Metabolic syndrome is the umbrella term used for a variety of risk factors that increases the risk of heart disease and other health problems. Five conditions that are metabolic risk factors are: high Body Mass Index, insulin resistance, low HDL cholesterol, high blood pressure, and high fasting blood sugar. Obesity, an example of a metabolic disorder, has been the focus of research and medical discussions because of the alarming impacts that it is having on the health of millions of citizens in the United States. According to the Center of Disease Control and Prevention growth charts, last year 17% of children in America from age 2-9 were obese and 32% were overweight (Blumberg, 559). As a result, obesity costs the U.S. healthcare more than $200 billion and these costs will continue to increase as the number of obese individuals escalates (Janesick 2016, 559).

With over 22.5% of the current U.S. population considered to be clinically obese, compared to only 14.5% in 1980, there does not seem to be a cessation of this epidemic in sight (Hill & Peters, 1998). Goran and Weisners' (2000) proposal that "... the inherently lower resting metabolic rate in women versus men is responsible for the higher adiposity rates in women..." is wanting, especially since the potentially modifiable factors of; less physical strength, less daily free-living physical activity, and lower total energy expenditure are more likely the cause of the differences in observed adiposity between men and women. Since our genetic makeup has not appreciably changed in the last twenty years, we cannot strictly attribute the explosion of obesity to genetics. As these biological causes of obesity are disproved, a focus on the environment as a reason for obesity is taking centre-stage.

In The Sedentary (R)evolution there is a complete agreement with Ratey and Manning (2014) that humans suffer from the afflictions of modern civilization that have caused metabolic syndrome. This article agrees with how the problem arose and that the hunter-gatherer lifestyle of our ancestors is the answer. “Foraging is the vital need to search for food based on locomotion, which requires energy expenditure in the form of running, sneaking or sprinting to plunder big or small game or climbing and stooping in order to collect honey, berries, nuts, seeds and plants” (Freese et al., 2018). It seems that research is pointing to the evolution of metabolic syndrome coming from civilization and that we must stay true to our genes to adapt in a healthy

Resting metabolic rate varies between individuals due to being fasted and rested, since digesting a meal or recovering from a session of exercise can affect a person’s RMR. RMR can be affected by factors which may include: males having a higher RMR than females, RMR increases a person’s body weight, eating a small meal portion increases an individual’s RMR or being a tall person will have a higher resting rate than a short person; also gaining more muscles will increase a person’s RMR.

In 1964 Fabry et al. randomly selected and surveyed a group of 179 males regarding their eating habits (3). Subjects were then divided into groups based upon the number of meals they consumed per day. Skinfold thickness measurements were taken to determine body fat percentage. Fabry et al. found that as meal frequency (MF) increased, the percentage of overweight subjects decreased within each study group (3). Since that time, the correlation between increased MF and weight loss has become a highly debated topic in weight loss or maintenance.

The Basal Metabolic Rate is essentially a measure of the required amount of energy needed to maintain bodily function while at rest. The most significant requirements that BMR energy needs meet are in processes such as establishing and maintaining a normal breathing pattern, heartbeat, blood circulation and temperature. The primary factors influencing BMR include age, gender, muscle composition, hormonal levels, exercise levels and many more. It is important to recognize that an individual’s BMR is not static and many of the above factors can affect the utilization of energy either positively or negatively. For example, men on average have higher BMRs when compared to women simply due to an increased amount of muscle mass. While it may seem

Epidemic has become the term of choice when discussing obesity in North America, and the struggle against the disease continues since effective long-term treatment has yet to appear. Obese individuals also often face prejudice, due to a common misperception that their condition solely results from lifestyle choices. However, studies show that environment accounts only for 50-65% of occurrence (Campfield et al. 1997, Bouchard and Perusse 1993 as cited by Campfield et al. 1996), leaving much to genetic influence. Recently much attention has been directed at the OB protein, or leptin, pathway due to its apparent influence on obesity-related components. Under the current context, leptin’s most important biological role is as an indicator of appetite satiety (Campfield et al. 1996). Generally, leptin levels have been found to increase with food intake and decrease with hunger (Coll et al. 2007). In normal function, leptin circulates in the bloodstream, and appropriately, OB-R receptors have been found in the brain and peripheral tissues (Campfield et al. 1996).

The causes of obesity are various; along with the genetics and psychological factors, the other considerable main factors are lack of energy balance and inactive lifestyle. In fact, obesity in America seems to increasing due to the imbalance in lifestyle of modern living. Research found that a rise in fast food, which make up to about 11% of American diet, its consumption correlated to a rise in body mass index as trans-fat are input

Researches studies differ on whether obese consume more energy (calories) than non-obese individuals. Some show they do consume more; others show they may consumer fewer calories. The big difference may be in the type of nutrients that they consume, such as fat. For example, Gazzaniga, found that the percentage of body fat was positively correlated with total dietary fat. Still, other researchers suggest that the reasons are metabolic in origin and that obese individuals "process" foods differently resulting in an increase in body fat. Although how these factors affect obesity are not fully understood, one thing is clear: Obesity results when energy intake exceeds energy expenditure and is stored as fat.

Many studies have been carried out to determine the genetic base of obesity. As result, mono and polygenic obesity have been revealed by scientists with the polygenic form stated as the most common. More than 100 and 200 genes respectively in human and mice have been identified to be related with obesity. As example, a defect in the gene coding for leptin, a hormone involved in regulation of appetite, abnormalities enzyme prohormone convertase that convert the hormone proopiomelanocortin (POMC) into neuropeptides, can deregulate energy metabolism. Genome wide scans in different ethnic populations have identified major obesity loci on chromosomes 2, 5, 10, 11 and 20 [9]. Recent genetic studies have identified several different causative mutations

There are many factors that contribute towards obesity, which primarily occurs due to a person’s caloric intake exceeding energy expenditure over a period of many years (ref). Reasons for the increasing prevalence of this condition are a combination of environmental influences interacting with predisposing genetic components (Elliott et al, 2008). Investigating causes of obesity’s prevalence is important so that effective public healthcare policies and nutritional and physical

Cardiovascular diseases are the number one factor that can erupt from obesity due to the main causes that it brings, like high blood pressure, and LDL cholesterol to a high count while lowering HDL. LDL is the “bad cholesterol”, and HDL is the “good cholesterol”. We need fats in our body for energy or ATP, in our body. If we get more LDL, it can really be a dangerous case, and

Energy expenditure is characterized by the number of kcal used by the human body per day. In healthy individuals, energy expenditure can be divided into basal metabolic rate (BMR), thermic effect of food and physical activity. In not so physically active individuals or hospitalized individuals, the BMR is by far the largest component of total daily energy expenditure, accounting for around 60-75% of total expenditure1,2,3,4. It’s the energy required to maintain the organism functions, temperature and survival and, in healthy individuals, it can vary according to differences in body composition (fat free mass proportion), weight,