Experiencing hunger (or a lack of) can be rather unpleasant. However, knowledge is power, and understanding WHY you are feeling a certain degree of hunger can help you respond in a more rational, logical manner.
As this infographic explains, hunger is primarily driven by our body’s current state of energy balance and body composition. Furthermore, it’s important to clarify that hunger and appetite are not synonymous; hunger is heavily dictated by our physiology, whereas appetite is influenced by our environment, lifestyle and psychology.
Given this, true physiological hunger and the body’s genuine desire to eat is the result of a complexity of factors - those that we have tried to make easy for you to interpret in this diagram!
Follow the arrows above to understand how hunger is regulated in the human body, and the influence that energy balance, energy expenditure, digestion, exercise habits and body composition have on regulating our overall energy intake.
Importantly, take note that body composition plays a major role in influencing our appetite hormones, sometimes to a disproportionate level regardless of absolute energy intake.
For example, a conditioned bodybuilder is likely to experience continuous levels of elevated hunger, regardless of how “high” their calorie intake is. This is due to the individual having significantly low levels of body fat, thus they have suppressed secretion of leptin, the hormone which is responsible for inhibiting hunger.
On the contrary, someone with an excessively high amount of adipose tissue can experience endocrine dysregulation, which too can disrupt their “normal” hunger cues. In this circumstance, regardless of total circulating leptin levels (which should be elevated as a result of having more body fat), the individual can be in a state “leptin resistance”, and thus they continue to have an internal hunger drive despite energy balance being sound.
What’s the sweet spot for regulating hunger? Ultimately, a sustainable body composition with a proportionate ratio of skeletal muscle:body fat. Nourishing + satiating dietary intake will also play a major role, as will exercise demands coincided with adequate sleep.