Negative energy balance

Menstrual cycle disturbances, including amenorrhoea, are a response of young women to prolonged negative energy balance. 

Definition of negative energy balance, and its role in weight reduction... 

Weight reduction is achieved with a negative energy balance, that is, decreasing caloric... 

The higher such difference, the more performing is the process. A process with a negative energy balance has no sense, as such a process is a net emitter of C02. 

PEM arises due to a negative energy balance, that is, a combined intake of proteins and calories less than that required for body expenditure. Inadequate food intake in PEM may have multiple causes, ranging from secondary malnutrition to sociopolitical problems (Fig. 24-2). 

Lay publications are inundated with fad diets designed to reduce body weight "quickly and easily" using a variety of caloric restrictions (68). Most individuals attempt to produce a negative energy balance and reduce body weight by decreasing food intake. 

Body lipids are mobilized during exercise and are oxidized readily during strenuous exercise like gafloping. Physically conditioned horses oxidize fat more efficiently than nonconditioned horses. Hyperlipidemia is an important clinical problem in small pony breeds. It is most common in mares in late gestation and lactation and occurs when the animal is in negative energy balance. 

Disturbance of some or almost all biochemical functions, also with a negative energy balance (= partial or global insufflciency) (see chapter 20) ... 

Bjomtorp, P. (1985). Regional patterns of fat distribution. Ann. Intent. Med. 103,994r-995. Bouchard, C-, and Tremblay, A. (1997). Genetic influences on the response of body fat and fat distribution to positive and negative energy balances in human identical twins. /. Nutt. 127, 943S-947S. 

Neuropeptide Y (NPY) is a potent appetite stimulant expressed by neurones of the hypothalamic arcuate nucleus (ARC) that project to important appetite-regulating nuclei, including the paraventricular nucleus (PVN). It also inhibits thermogenesis. Repeated administration rapidly induces obesity. The ARC NPY neurones act homeostatically to correct negative energy balance. They are stimulated by starvation, probably mediated by falls in circulating leptin and insulin (which both inhibit these neurones),... 

Table 7.1 Intrapair Resemblance in the Response of Obesity Phenotypes to Overfeeding and Negative Energy Balance Protocols in Monozygotic Twins...

The changes observed in all phenotypes following overfeeding and negative energy balance were significant (p < 0.01). 

---