Hello doctor, I am suffering from loss of appetite. I can even go for three days without thinking about food. What would be the problem? Please advise- Desire
Dear Desire:
This is a tricky question because although food that is consumed is more guided by appetite (desire) than by hunger (need), many think by not being hungry, they luck appetite. It is therefore important to begin by ascertaining whether your symptom is luck of appetite or not feeling hungry.
Hunger vs appetite
Hunger comes on slowly and is the result of a physiological need to eat, it is triggered by the mechanical stimuli of the stomach being empty, and your body seeks to reduce the sensation of an empty stomach by consuming needed fuel. This sensation triggers stomach cells to release a hormone called ghrelin which stimulates the nerve which runs between the stomach and brain called the vagus nerve.
The hormone ghrelin stimulates an area of the brain that controls hanger called the hypothalamus which initiates food-seeking behaviors.
Hunger is also accompanied by a lack of energy and enthusiasm (lethargy) and a growling stomach. Therefore, any condition affecting either stomach cells, the vegas nerve or the hypothalamus may present with a luck of feeling hungry. For example, any inflammation in the stomach (gastritis), wounds (ulcers), cancers, injury (damage to any of the three) and an infection may cause this luck of hunger.
On the other hand, appetite comes on suddenly and is driven by the brain’s desire to eat a specific thing, implying that an individual who has an appetite may suddenly want to eat a specific food even if they are not hungry.
It is usually, for a specific kind of food and gives less of a feeling of satisfaction. It is driven by an emotional or mental desire, and the brain will use appetite to guide the body to eat certain nutrients it may be lacking, by causing craving. For instance, the desire to have high-protein meal after a workout, and losing the desire to eat certain soup if the brain senses the soup has a fly in it.
Need for investigation
Loss of appetite whether alone or in association with other signs like loss of weight, may indicate an infection like Tuberculosis (TB) or certain cancers especially gastral intestinal cancers. This always warrants investigation to be ruled out or confirmed. Anything that may stress our emotions centers may affect our desire for food as well.
