It has been hours since your last meal, but instead of feeling hungry, why does hunger cause nausea? A lot of people have experienced that feeling, but it is hard to comprehend. Why wouldn't your body like food at a time when it's most needed?

Christine Lee told Live Science that there is a simple explanation for this phenomenon.


Dr Christine Lee, MD


Your stomach makes hydrochloric acid when it breaks down food, using what it can for energy and materials, and disposing of the rest. The hydrochloric acid can build up if you don't eat for a while.

It can cause acid reflux, heartburn and nausea when it gets into the esophagus.


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Your body's network of signals for knowing when to eat is one of the reasons why you might feel nausea when hungry. The signals are regulated by the endocrine system, a system of glands that use the bloodstream to communicate.

Your body gets information from the hormones generated by the endocrine system. To support a wide range of bodily activities you need calories. The hormones in your stomach tell the brain "Give us more calories" or "That's enough" Ghrelin and leptin are two hormones that play a role.

"Ghrelin is supposed to make you hungry," Lee stated. Ghrelin has been found to be a key player in a number of important processes in the body.

The effect of leptin is to decrease appetite. The interplay between leptin and ghrelin is important in the ebb and flow of appetite.

woman eating egg on toast at a restaurant

(Image credit: Getty Images)

The hormones auto-regulate when your body is in a normal state. You should only have a few signals to remind you to eat.

Your body releases leptin when you eat, which means that you don't need to be hungry for a long time. Your body needs food in order to make ghrelin. So you eat. The leptin is produced by your body because it doesn't need more food. You stop eating when you feel like you're full.

The chemical balancing act can be thrown out of whack if you don't eat often. Your body will try to get you to eat if you don't eat for a long time.

The hormones are supposed to increase your appetite. This is the way most people do it. Sometimes, but not always.

Some people are more sensitive to hormones. Light nausea can be caused by variation in sensitivity and other factors. There are cases of more severe nausea.

If you get nausea or pain, it could be your body telling you that you need to be screened for a condition called metabolic syndrome, which can lead to heart disease.

The original was published on Live Science in October.

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