What is Really Affecting Your Appetite?

Some days it feels like you can eat the whole pizza by yourself. Other days, you take only a few bites of your food and you feel nauseous. Your appetite can seem unpredictable at times, and it can lead you to go hungry, trying to resist cravings, or feel weak because it seems you just can’t keep anything down.

What is it that controls our appetite?
Why does it change so much from one day to the next? Is there anything we can do to help make it more predictable?

In this article, we will explore all of these questions so you can not only have a better understanding of what affects your appetite, but also how to help ensure some stability regarding your food intake.

►First of all, what exactly is an “appetite” ?

According to the Mirriam-Webster dictionary, an appetite is a "physical desire for food" This means that not only are you tempted by the idea of eating (whether it is specific or not), but your body seems to demand it.

The British Medical Bulletin goes further, saying that "thirst and specific appetites are the dispositions to eat or to drink water and specific nutrients in whatever materials contain them"
Once you no longer have an appetite, you feel satiety (fullness). Other texts equate appetite to craving, making the                                                                                 concept much more subjective.

If you have a big appetite, you feel like you have to eat copious amounts of food before feeling full or satisfied. If you have a small appetite, you feel like you’ve had enough even after a few bites.

►What Affects Your Appetite ? The Physiology of   Appetite.

Appetites can be caused by a biological need for certain foods (or food in general), or appetites can be learned.

In the biological arena, appetite is controlled by what are called “hunger hormones”, which communicate with the hypothalamus in the brain. These hormones are, namely, leptin and ghrelin.

Leptin is made by the fat cells in your body and decreases your appetite, while ghrelin, released in the stomach increases your appetite. In general, when you are thin, you generally have higher levels of ghrelin, in order to increase food consumption, and thus weight gain. When you are overweight, you generally have higher levels of leptin (because you have a higher number of fat cells)

In normal circumstances, ghrelin goes up right before we eat, triggering a feeling of hunger. The same also happens when you go longer without eating than normal.

After we eat, it normally goes down for about three hours after we eat, when out stomach is distended. At this point, leptin tells our brain we have enough energy stores, and our appetite decreases.

But then, you might be thinking, why do overweight and obese people often have a tendency to have big appetites?

Research suggests that our body can build resistance to the effects of leptin over time, if we don’t respond to the appetite suppressing effects like we should. This could be due to the second element that affects appetite: cues.

Cues trigger learned responses through habit. If we get used to eating lunch as soon as the warm midday sun shines through the windows onto our desk, even if we just ate breakfast, we will start to feel hungry when we see the sun hits our paperweight.

Other cues include smells or sounds, which, when they are really well engrained in our minds, can even cause us salivate even if food is nowhere to be seen.