When you haven't eaten in several hours, your blood sugar (glucose) levels drop. Your body sends hunger signals to your brain, which makes your stomach growl and stimulates your appetite. Sound familiar? Most of us have been there before and (besides the annoyance of an empty stomach) there is usually no cause for concern.
But sometimes, you might experience other symptoms, like heart palpitations, when you're hungry. If your blood sugar levels drop below healthy levels, hypoglycemia occurs. Hypoglycemia can cause rapid heart rate, palpitations, and other symptoms.
How Hunger Becomes Hypoglycemia (Low Blood Sugar)
Hunger is your body's cue that it needs food. It is the feeling you get when you haven't eaten in a while and, as a result, your body is short on energy. Hunger motivates the consumption of food.
Glucose (blood sugar) is the body's main source of energy, which comes from the foods you eat. After the food is broken down, glucose is released into the bloodstream, where it reaches every cell in the body and is used as an energy source. Vital organs, including the heart, need sufficient levels of blood sugar in order to function properly.
Hypoglycemia occurs when the body has too little blood sugar. For most people, this is when your blood sugar levels drop below 70 milligrams per deciliter (mg/dL). People with diabetes may experience hypoglycemia as a side effect of the diabetes medicines they take.
Though hypoglycemia is most common in people with diabetes, people without diabetes can also be affected.
Common causes of low blood sugar in people without diabetes include:
- Certain medications (e.g., beta blockers, lithium)
- Excessive alcohol consumption
- Fasting (not eating)
- Gastric bypass (weight loss) surgery
- Insulin overproduction
- Other health conditions, including hormonal imbalances, liver disease, kidney disease, severe infections, and advanced heart disease
When your blood sugar levels drop too low, you may experience symptoms of hypoglycemia, which may include:
- Rapid heartbeat
You may not experience every symptom during a hypoglycemic episode. Symptoms vary from person to person, and some people do not have any symptoms at all.
Can Hunger Cause Heart Palpitations?
Your body needs sufficient amounts of blood sugar in order to function properly. When your glucose levels are too low, your body systems and vital organs do not have sufficient energy to function as they should. If you notice your heart beating rapidly when you're hungry, it is possible that your blood sugar levels are too low.
Research shows that low blood glucose levels increases heart rate in people with and without diabetes. This is because hypoglycemia triggers the release of adrenaline (epinephrine) - the body's stress hormone. This is what causes hypoglycemia symptoms, such as a racing heart, heart palpitations, sweating, and anxiety. Over time, severe hypoglycemia is associated with an increased risk of heart disease.
How to Treat Hypoglycemia
Treating hypoglycemia quickly and preventing future episodes can help prevent long-term health complications.
Treating Low Blood Sugar with Diabetes
If you have diabetes and your blood sugar levels have dropped too low, check your blood sugar level and then follow the 15-15 rule:
- Eat 15 grams of carbs
- Check your blood sugar 15 minutes after
If your blood sugar level is still too low, have another 15 grams of carbs. Repeat every 15 minutes until your blood sugar level is within the target range recommended by your healthcare provider. Once it's within that range, eat a healthy meal or snack to ensure your glucose levels stay within normal ranges.
Treating Low Blood Sugar Without Diabetes
If you don't have diabetes and are experiencing hypoglycemia symptoms such as a rapid heart rate, you can still follow the 15-15 rule. This means you'll want to eat something with a high glycemic index to boost your blood sugar as quickly as possible. MedlinePlus recommends foods that have around 15 grams of carbohydrates, such as:
- 5 to 6 hard candies
- ½ cup of fruit juice
- 1 tablespoon of honey
Other foods that contain 15 grams of carbohydrates include:
- 17 small grapes
- 1 ¼ cup of strawberries
- 1 cup of milk
- ¼ of a large bagel
- ¼ cup of granola cereal
- 3 graham crackers
- 2 rice cakes
Wait 15 minutes and if you're still experiencing symptoms of low blood sugar, eat another 15 grams of carbs. If your blood sugar is still low after another 15 minutes, seek medical attention.
How to Prevent Hypoglycemia
- Create and stick to a regular eating schedule, including meals, snacks, and beverages that contain sufficient amounts of carbohydrates.
- Do not skip meals.
- Eat a snack before exercising or any moderate to intense physical activity.
- If you drink alcoholic beverages, eat food at the same time.
- Regularly check your blood sugar levels with a blood glucose monitor (if you have diabetes).
If you're hungry and experiencing heart palpitations, low blood sugar may be the culprit. Eat something high in carbohydrates and wait 15 minutes to see if your heart settles into a more normal rhythm.
Other Causes of Heart Palpitations
Hypoglycemia isn't the only cause of an irregular heartbeat. According to the Cleveland Clinic, a rapid, fluttering, or pounding heart can be caused by:
- Certain medications, like asthma inhalers, beta blockers for heart conditions, and thyroid medicines
- Emotions, such as anxiety, fear, panic, and stress
When to Seek Medical Attention for Heart Palpitations
If you don't have diabetes and regularly get symptoms of low blood sugar, see your healthcare provider. They will run tests to check your blood glucose level and try to determine the cause. If you do have diabetes, talk to your doctor about your hypoglycemic episode(s). They may recommend adjusting your treatment plan to help control your blood sugar levels.
Seek immediate medical attention if:
- Your blood sugar levels are not improving after drinking juice or eating foods high in carbohydrates
- You feel confused, dizzy or experienced a loss of consciousness
- You have symptoms such as shortness of breath, chest pain, and/or fainting along with heart palpitations
Your healthcare provider may be able to refer you to a registered dietitian who can help you come up with an eating plan that reduces any uncomfortable symptoms and also fits in your lifestyle so that it is easy to maintain.