Why Do I Feel Weird on an Empty Stomach?

According to a study published in the journal Physiology & Behavior, the sensation of hunger can trigger negative emotional states like irritability and anger, a phenomenon popularly known as "hanger". This isn't just a mental quirk; it's one of several biological reasons why you feel weird on an empty stomach.

Quick Summary

This guide explores the common reasons for feeling unwell when hungry, including hormonal changes, low blood sugar, and stomach acid buildup. It also covers how stress and dehydration can intensify symptoms and provides practical strategies to manage and prevent discomfort.

Key Points

• Low Blood Sugar: When glucose levels drop from an empty stomach, the brain lacks its primary fuel source, causing dizziness, shakiness, and fatigue.

• Ghrelin Release: The 'hunger hormone,' ghrelin, is released by an empty stomach, signaling the brain to eat and contributing to feelings of irritability and mood changes.

• Excess Stomach Acid: Without food to absorb it, stomach acid can build up, leading to a gnawing sensation, nausea, or acid reflux.

• Dehydration: Feelings of thirst can sometimes be confused with hunger, and dehydration can cause symptoms like lightheadedness and fatigue that intensify the feeling of being unwell.

• Stress and Anxiety: The gut-brain axis means stress and anxiety can directly impact your digestive system, leading to or worsening nausea and other weird stomach feelings.

• Balanced Meals and Snacks: Eating regularly and including a mix of protein, whole grains, and healthy fats can help stabilize blood sugar and prevent discomfort.

• Seek Medical Advice: Persistent, severe, or unexplained symptoms like nausea, weakness, or rapid weight changes should prompt a visit to a healthcare professional.

The Biological Basis of Feeling 'Weird'

The unsettling sensations that arise from an empty stomach are not a figment of your imagination. They are a complex series of physiological responses designed to signal your body's need for fuel. When you haven't eaten, your body enters a state of mild energy crisis, which triggers a cascade of hormonal and neurological effects. The primary reasons behind feeling "weird" include changes in blood sugar, shifts in hormone levels, and the effect of stomach acid.

Hormonal and Blood Sugar Changes

• Hypoglycemia (Low Blood Sugar): Your brain relies heavily on glucose for energy. After several hours without food, your blood glucose levels drop, triggering a response to conserve energy. The result can be shakiness, dizziness, lightheadedness, and difficulty concentrating. This is one of the most direct and common causes of feeling unwell on an empty stomach.
• Ghrelin, the 'Hunger Hormone': Your stomach produces ghrelin when it's empty to signal your brain that it's time to eat. This hormonal signal can influence mood and behavior, leading to the irritability associated with 'hanger'. High ghrelin levels are often accompanied by other physical symptoms as the body prepares for food intake.
• Impact on Mood: The drop in blood glucose combined with rising ghrelin levels can directly impact your mood. Research indicates a strong link between hunger and negative emotions such as anger and anxiety. The brain's reduced energy supply can also impair self-regulation, making it harder to control emotional responses.

Digestive and Neurological Factors

• Stomach Acid Buildup: Your stomach continuously produces hydrochloric acid to break down food. When your stomach is empty for too long, this acid can build up and cause discomfort, a gnawing sensation, or nausea. For some, this can lead to acid reflux as the stomach acid irritates the esophageal lining.
• The Gut-Brain Axis: The complex connection between your gastrointestinal tract and your brain, known as the gut-brain axis, plays a significant role. Signals from an empty or upset stomach can influence your mood, and similarly, stress or anxiety can cause physical stomach symptoms. This creates a two-way street where an empty stomach can increase anxiety, and anxiety can worsen stomach upset.

Lifestyle and Environmental Contributors

Certain habits and external factors can exacerbate the weird feelings you get from an empty stomach. Understanding these can help you manage your symptoms more effectively.

Comparison of Empty Stomach vs. Dehydration Symptoms

Symptom	Empty Stomach (Low Blood Sugar)	Dehydration
Dizziness/Lightheadedness	Common, due to lack of brain fuel.	Common, due to reduced blood volume and pressure.
Nausea	Can be caused by acid buildup or hormonal changes.	Can be caused by an imbalance in bodily fluids.
Fatigue	Occurs as the body conserves energy.	Occurs as the body's systems struggle to function.
Irritability/Anxiety	Directly linked to blood sugar drops and hunger hormones.	Can be a symptom, but is more often a result of discomfort.
Physical Feeling	Gnawing or rumbling in the stomach.	Dry mouth, increased thirst, dark urine.

The Impact of Stress, Sleep, and Dehydration

• Stress and Anxiety: Stress hormones can affect your digestive system and blood sugar levels. For some, anxiety can suppress appetite, while for others, it can lead to overeating. In either case, the stress response can intensify feelings of nausea or discomfort when you're hungry.
• Sleep Deprivation: Lack of sleep disrupts the balance of appetite-regulating hormones, specifically ghrelin and leptin. This can increase hunger signals and cravings, making the "weird" feelings from an empty stomach more pronounced. Poor sleep also increases stress, which further complicates digestive health.
• Dehydration: Thirst and hunger signals can be confused by the brain. Not drinking enough water can lead to dizziness, fatigue, and headaches, all of which can be mistaken for or intensify the feelings of being hungry. Staying hydrated is a simple yet powerful way to manage these sensations.

Strategies to Manage the Feeling and When to Seek Help

Most cases of feeling weird on an empty stomach can be managed with simple lifestyle adjustments. Eating regular, balanced meals is the most effective approach. When hunger strikes between meals, having a healthy snack can prevent symptoms from escalating.

Actionable tips include:

• Eat balanced meals with a mix of lean protein, whole grains, and healthy fats to provide sustained energy and prevent sharp blood sugar drops.
• Keep nutritious, portable snacks on hand, such as nuts, fruit, or yogurt, for when hunger strikes unexpectedly.
• Stay well-hydrated throughout the day by sipping water regularly.
• Practice mindful eating to better recognize your body's true hunger and fullness cues.
• Manage stress through exercise, deep breathing, or meditation to minimize its effect on your gut.

It is important to remember that while occasional discomfort is normal, persistent or severe symptoms warrant a medical consultation.

Conclusion

The "weird" feeling on an empty stomach is a physiological response to a drop in blood glucose, the release of hunger hormones like ghrelin, and a buildup of stomach acid. Exacerbated by factors like stress, poor sleep, and dehydration, these symptoms can be unsettling but are usually manageable with proper nutrition and healthy habits. By understanding the biological mechanisms at play and adopting mindful eating strategies, you can minimize the discomfort and maintain your well-being. If symptoms persist or are severe, consulting a healthcare professional is recommended to rule out any underlying medical conditions.

Frequently Asked Questions (FAQs)

Is feeling weird on an empty stomach a sign of a health problem?

For most people, it's a normal and healthy signal that your body needs fuel. However, if symptoms are severe, frequent, or accompanied by other issues, it could indicate an underlying condition like a digestive disorder or diabetes.

Can anxiety be a cause of feeling weird on an empty stomach?

Yes, there's a strong link between anxiety and the gut-brain axis. Anxiety can trigger digestive upset and a fight-or-flight response, which can both mimic and intensify the physical sensations of an empty stomach.

What is 'hanger,' and is it real?

Hanger, a portmanteau of 'hungry' and 'angry,' is a very real phenomenon. It stems from a combination of low blood sugar affecting the brain's function and the release of stress hormones, which can lead to irritability and poor impulse control.

Can dehydration cause me to feel weird when I'm hungry?

Yes, the brain can often confuse thirst and hunger signals, so dehydration can manifest with symptoms similar to hunger, such as lightheadedness and nausea. Staying hydrated is a key step in managing these feelings.

How long should I wait to eat if I feel weird on an empty stomach?

If you feel unwell, it's best to eat as soon as possible. Opt for a quick source of simple carbohydrates, like a piece of fruit or juice, to raise your blood sugar quickly, followed by a balanced meal.

Are there certain foods that can prevent this feeling?

Eating balanced meals rich in complex carbohydrates, lean protein, and fiber can help regulate blood sugar and keep you feeling full longer. Examples include whole grains, legumes, vegetables, and nuts.

When should I see a doctor about this issue?

You should see a doctor if the "weird" feeling is consistently accompanied by more severe symptoms such as persistent nausea, frequent vomiting, significant changes in weight, or unusual weakness or confusion.

Citations

• Swami, V., et al. (2022). "Hangry in the field: An experience sampling study on the impact of hunger on anger, irritability, and affect." PLoS ONE. https://www.nutritional-psychology.org/food-and-mood-is-the-concept-of-hangry-real/
• Bass Medical Group. (2025). "Morning Nausea? Why You Might Feel Sick to Your Stomach." https://www.bassmedicalgroup.com/blog-post/sick-to-your-stomach-in-the-morning
• Mayo Clinic. (2023). "Hypoglycemia - Symptoms and causes." https://www.mayoclinic.org/diseases-conditions/hypoglycemia/symptoms-causes/syc-20373685
• Cleveland Clinic. (n.d.). "Ghrelin Hormone: Function and Definition." https://my.clevelandclinic.org/health/body/22804-ghrelin
• Healthline. (2020). "Nausea When Hungry: Causes, Treatment, and Prevention." https://www.healthline.com/health/nausea-when-hungry
• Oshi Health. (2024). "How to overcome anxiety and stomach issues." https://oshihealth.com/how-to-overcome-anxiety-and-stomach-issues/
• Medical News Today. (2024). "Hunger pangs (pains): 7 causes and how to alleviate them." https://www.medicalnewstoday.com/articles/321725
• Cleveland Clinic. (n.d.). "Dehydration: Symptoms & Causes." https://my.clevelandclinic.org/health/diseases/9013-dehydration
• Healthline. (2022). "Can Not Eating Make You Dizzy? A Dietitian Explains." https://www.healthline.com/nutrition/can-not-eating-make-you-dizzy
• Cleveland Clinic Health Essentials. (2023). "Hunger Pangs: What They Are and Causes." https://health.clevelandclinic.org/hunger-pangs
• Healthline. (2020). "Can Vertigo Be a Symptom of Dehydration?" https://www.healthline.com/health/can-dehydration-cause-vertigo
• Healthline. (2017). "Hunger Pangs: Causes, Management, When to Seek Help." https://www.healthline.com/health/hunger-pangs
• Healthline. (2023). "Anxiety and Loss of Appetite: What to Do About It." https://www.healthline.com/health/mental-health/anxiety-lose-appetite
• Ochsner Health. (2025). "Why Do I Feel Like Throwing Up, but I Don't?" https://blog.ochsner.org/articles/feeling-nauseous-but-not-throwing-up/
• Mayo Clinic. (2024). "Dizziness - Symptoms and causes." https://www.mayoclinic.org/diseases-conditions/dizziness/symptoms-causes/syc-20371787
• nhs.uk. (n.d.). "Low blood sugar (hypoglycaemia)." https://www.nhs.uk/conditions/low-blood-sugar-hypoglycaemia/

Frequently Asked Questions

What is the primary cause of feeling weird on an empty stomach?

The primary cause is often low blood sugar, or hypoglycemia, which happens when the brain is deprived of its main energy source. This can lead to dizziness, shakiness, and irritability.

Can an empty stomach cause nausea?

Yes, an empty stomach can cause nausea. This may be due to a buildup of stomach acid that irritates the stomach lining, or because of hormonal changes that signal hunger.

Why do I feel dizzy when I'm hungry?

Dizziness when hungry is often a sign of low blood sugar. The brain needs a constant supply of glucose to function correctly, and when levels drop, it can lead to lightheadedness or a dizzy feeling.

Is it possible to confuse thirst with hunger?

Yes, it is very common to mistake thirst for hunger. The brain's signals can be similar, and dehydration can cause fatigue and lightheadedness that feel like hunger.

How can stress affect my stomach when I'm hungry?

Stress and anxiety can trigger the gut-brain axis, causing physical symptoms in the stomach such as nausea or a knot-like sensation. This can be intensified when you are already hungry and your digestive system is unsettled.

What's the best way to prevent feeling weird when I haven't eaten?

The best way is to maintain a consistent eating schedule and include balanced meals and healthy snacks. Staying well-hydrated throughout the day also helps prevent symptoms.

When should I be concerned and see a doctor about this feeling?

You should consult a doctor if the weird feeling is chronic or accompanied by severe symptoms, including persistent nausea, vomiting, dizziness, unexpected weight changes, or unusual fatigue.