Appetite regulation and physical activity – an energy balance perspective

Abstract

In addressing the topic of appetite regulation, energy balance and physical activity, there are many reasons why it is appropriate to consider these issues conjointly in relation to the phenomenon of obesity. Firstly, it is widely recognized that obesity arises from a mismatch between energy taken in and energy expended, although this is not a simple matter of calculating the algebraic sum of two numbers. Secondly, recent evidence has revealed that appetite control (responsible for energy intake) is closely related to the energy requirements of the body, in contrast to the conventional approach of appetite emerging from the regulation of body fat (lipostatic hypothesis). Thirdly, physical activity is obviously implicated in energy balance and therefore connected to both energy intake (appetite control) and the control of body tissue stores (obesity). Finally, for the management of obesity, increasing physical activity (moving more) and decreasing dietary intake (eating less) are two of the major principles in the medical and public health arenas. This review will deal with research and theory relating to human obesity, with the objective of providing a synthesis relevant to understanding the predicament that this phenomenon is causing. One major reason for addressing the problem in this way is because, in recent years, it has become apparent that the observed increase in obesity, worldwide, is associated with an overconsumption of food (a problem related to appetite control) and a sedentary lifestyle (a problem related to physical activity), and the relationship between the two (an issue related to energy balance). Accordingly, investigations in this area should provide insights into how to deal with overconsumption and with sedentariness for the management of obesity. This review is about energy intake and energy expenditure and how they influence the human capacity to live healthily in a modern world.