Many people experience dizziness before a meal. Low blood glucose can make a person feel light-headed or exhausted, especially if it has been a long time since their last meal. Dizziness after eating is less common, but it can also occur.
Some medical conditions and food sensitivities may trigger dizziness after a meal. Doctors sometimes refer to dizziness after eating as postprandial vertigo.
There are several techniques that people can use to minimize this symptom.
In this article, we look at five factors that can cause dizziness after eating and explain how to prevent it.
Blood sugar usually rises after a meal. The rise in blood sugar after eating is why people who feel dizzy before eating often feel better afterward.
When blood sugar drops following a meal and causes dizziness after eating, doctors call it reactive hypoglycemia. People with diabetes or prediabetes may experience blood glucose drops after a meal because their body produces too much insulin.
However, people without diabetes can get this type of hypoglycemia too. For example, people who have had stomach surgery may digest foods too quickly, making it harder for the body to absorb glucose from them. Rare deficiencies of certain digestive enzymes can also lower blood glucose.
A doctor can use tests to identify diabetes in people with the condition and prediabetes in those at risk.
Eating smaller, more frequent meals with lower sugar content may also help people who experience dizziness after eating because of low blood sugar.
People with high blood pressure are more likely to develop this symptom because high blood pressure can cause hardening and blockages in the arteries. These changes make it more difficult for blood to flow to the brain when it is also flowing to the digestive system. Reduced blood flow to the brain can result in dizziness.
The cause of the drop in blood pressure will determine the treatment.
In many cases, treating high blood pressure can help. Drinking more water before meals and eating more frequent but smaller meals, for example, six small meals instead of three large ones, may also improve symptoms.
Some diabetes medications, including insulin, may cause dizziness when they lower blood glucose too much. A person who takes their medication right before a meal may notice post-meal dizziness as the medication takes effect.
People with diabetes who regularly experience dizziness after a meal should talk to their doctor about changing their medication, taking a lower dosage, or adjusting their meal schedule.
Food sensitivities may cause some people to feel light-headed or nauseous. Certain drugs and chemicals, including caffeine and alcohol, may also cause dizziness after a meal.
People who frequently experience dizziness after eating may wish to consider keeping a log of these episodes and noting what they eat before each one.
Over time, it may become apparent that a specific food or group of foods is causing the dizziness.
Most people sit to eat a meal and then stand shortly afterward. Some people experience a sudden drop in blood pressure when they stand. When this happens, the problem is not the meal itself, but the sudden shift from a sitting to a standing position.
Orthostatic hypotension is the medical term for a blood pressure drop that occurs when a person moves from sitting to standing, but most people refer to this as a head rush.
Some potential causes include:
- nervous system disorders
- low blood sugar
- heart problems that make it difficult for the heart to pump enough blood when a person stands
- medications to treat high blood pressure
- excessive heat exposure
- infection or fever
- blocked blood vessels
- bleeding somewhere in the body, such as in the stomach
In people who only experience occasional blood pressure drops, drinking more water may help. Otherwise, it is important to see a doctor to ensure that there is not a serious underlying medical condition.
A single instance of dizziness after eating does not usually mean that a person has a serious medical condition. It may be that a person's blood sugar or blood pressure temporarily shifted or that something in their meal triggered dizziness. There is no need to see a doctor for a brief spell of dizziness.
Pregnant women who experience dizziness after a meal typically find that this symptom improves after delivery. However, if the dizziness is intense, prolonged, or interferes with the woman's functioning, she should call a doctor.
Rarely, very low blood pressure can cut off blood supply to the brain. When this occurs, it may cause an ischemic stroke, which can be life threatening. A person who has symptoms of a stroke should go to the emergency room or call 911 or the local emergency number.
The symptoms of a stroke include:
- numbness or weakness on one side of the face or body
- an inability to smile or move the mouth normally
- a drooping face
- a severe headache
- difficulty walking
- vision problems
A person who repeatedly gets dizzy after a meal should consult their doctor. People with diabetes who experience post-meal dizziness may need to adjust their medication or their eating schedule.
Some strategies may help reduce dizziness after eating. People can try the following:
- Drinking more water before and during meals.
- Avoiding alcohol, caffeine, and high sodium meals, which can increase the risk of dehydration.
- Sitting or lying down for 30–60 minutes after a meal.
- Eating fewer easily digestible carbohydrates, such as white bread and pasta. The body quickly digests these foods, and this may cause low blood pressure after a meal.
- Eating smaller but more frequent meals. Some people find that eating every 2–3 hours helps with post-meal dizziness.
- Asking a doctor about adjusting diabetes or blood pressure medications.
- Managing and treating any chronic medical conditions, especially diabetes and high blood pressure.
- Leading a healthful lifestyle that reduces the risk of blood vessel problems. Doing regular exercise, eating a balanced diet rich in a wide variety of nutrients, and maintaining a healthy weight can lower the risk of several conditions that may cause dizziness after eating.
Numerous conditions, ranging from benign to very serious, may cause dizziness after a meal. It is impossible to diagnose the cause based on symptoms alone. Therefore, it is important for a person who repeatedly gets dizzy after eating to see a doctor. By using a few simple tests, the doctor can usually identify the cause, recommend treatment options, and offer peace of mind.