You wake up late, rush out of the house and be picked up for a meeting as soon as you enter the office. Breakfast never happens and by the time you sit down to lunch, it's been almost 15 hours since your last meal. You should starve, but instead you feel sick.
How can that be? Why would your fasting body make food less attractive when it is most needed?
One of the most common causes of the phenomenon is easily understood, said Christine Lee, a gastroenterologist at the Cleveland Clinic. Your stomach produces hydrochloric acid as part of a long process of breaking down food, using whatever it can for energy and materials, and throwing away the rest. If you do not eat for an extended period of time, hydrochloric acid can build up in your stomach.
"When it gets stuck in the esophagus, it can cause acid, acid and nausea reflux," Lee says.
Related: What Causes Hunger Pains?
Another set of possible causes of feeling sick when starving is having a connection to your body's signal network to know when to eat. These signals are regulated by the endocrine system of the glands (including the pituitary, thyroid and pancreas), which uses the bloodstream for chemical communication.
Hormones generated by the endocrine system "give your body the information it needs to to maintain its balanced chemical levels. For example, to maintain healthy blood sugar levels and maintain a wide range of physical activities, you need calories. Your stomach sends signals to the endocrine system that trigger hormone production; these hormones tell the brain, "Give us more calories," or "That's enough." Many hormones are involved, but two important players are ghrelin and leptin.
"It is supposed that ghrelin will cause hunger," Lee said. The hormone was discovered in 1
Leptin has the opposite effect: It counteracts ghrelin by reducing appetite. There are many other hormones involved in hunger, but the interaction between ghrelin and leptin is key to a healthy outpouring and appetite flow.
"When your body is in a normal state, these hormones are regulated automatically," Lee said. You only need to have a few beeps throughout the day, reminding you to eat lightly.
As you eat, your body releases leptin, which signals that you are satisfied and do not need to be hungry for a while. In other words, your body needs food, so it produces ghrelin. It makes you hungry so eat. Then your body doesn't need more food, so it produces leptin. It makes you feel complete so you stop eating.
But this chemical balancing act can be thrown off the beat if you ignore your hunger signals and don't eat regularly. Go long enough without eating, and your body will try to get you to eat by producing more ghrelin.
"When hormones rise, they should increase your appetite," Lee said. And most people, most of the time, do just that. But not always.
"Some people have a higher sensitivity to hormonal levels," Lee says. Differences in sensitivity and other factors lead some people to experience mild nausea when extremely hungry. However, cases of more severe nausea symptoms may hint at the disorder.
"If your signals are intense enough to give you nausea or pain, it may be your body that tells you that you need to be tested for metabolic syndrome" – conditions such as high blood sugar, abnormal cholesterol, increased blood pressure and high blood sugar – which can lead to heart disease, Lee said.
Originally published on by Live Science .