Why do I faint after eating rice?

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Some people may experience fainting after eating rice. This phenomenon is medically known as postprandial hypotension. Although this condition can be reversed later, if the patient faints suddenly, a comprehensive examination is necessary to rule out serious medical conditions.

1. What is postprandial hypotension?

The digestive system requires increased blood flow after meals to digest food. This is ensured by dilation or widening of the blood vessels in the abdomen, along with a slight increase in local blood pressure. Abdominal hypertension can cause postprandial hypotension in the rest of the body. This can disrupt the normal functioning of the body and lead to serious consequences, manifesting as sudden fainting.
To prevent this, blood vessels in other parts of the body constrict or narrow after meals, to increase blood pressure in them and ensure adequate blood flow. That's why heart rate and blood pressure rise slightly after a meal. This timely change in blood pressure as well as the dilation and contraction of blood vessels involved is regulated by the autonomic nervous system.
However, in some people, the constriction of blood vessels in the rest of the body after a meal is not effective, causing a postprandial drop in blood pressure with fainting after eating. Hypotension or low blood pressure is when systolic and diastolic blood pressure falls below 90-60 mm Hg.
Signs and symptoms of postprandial hypotension are:
Dizziness and lightheadedness: This can happen at any time in 30-60 minutes after a meal; Fainting after eating rice; Nausea or vomiting, often mistaken for food poisoning; Angina or chest pain; Blurred vision; Feeling confused or disoriented; A mild stroke is called a transient ischemic attack.

2. Pathophysiological mechanism of postprandial hypotension

Postprandial hypotension may be due to insufficient sympathetic response to vasodilatation due to vasodilation. This hypothesis has been supported by inadequate or delayed heart rate elevations, inadequate plasma norepinephrine levels, and postprandial sympathetic nervous system activity in patients with postprandial hypotension.
After eating a meal, especially if you eat too much, the visceral arteries will dilate large to supply a necessary amount of blood to the digestive system. This results in a decrease in venous return volume, causing a heart-mediated hyperreflexia to maintain blood pressure. Accordingly, in a patient with autonomic dysfunction or in the elderly, a reflex increase in heart rate and total vascular resistance does not occur. As a result, there is a drop in blood pressure after eating, which can cause sudden fainting.

3. Causes and risk factors of postprandial hypotension

Some possible causes of postprandial hypotension in patients are:
Heredity: There is a family member with postprandial hypotension. Blood sugar: If a person has consumed a meal high in carbohydrates, blood sugar levels suddenly spike and thus insulin is known to interfere with the functioning of the autonomic nervous system. For the same reason, diabetics have a higher risk of postprandial hypotension than non-diabetics. High blood pressure: People with persistently high blood pressure are at increased risk for postprandial hypotension. This is because persistently high blood pressure makes the arteries stiffer and as a result, the dilation and constriction of blood vessels in different parts of the body do not take place effectively. Blood pressure sensors in the autonomic nervous system lose their sensitivity, eventually triggering hypotension. Other risk factors include:
Age: Age is the biggest risk factor, as postprandial hypotension affects people over 65 more than younger people. Diabetes: As explained above, diabetes and fluctuating blood sugar conditions can trigger postprandial hypotension. Parkinson's disease: Parkinson's affects the activity of the autonomic nervous system, one of the possible consequences is a drop in blood pressure after eating. Medication for high blood pressure: Patients with high blood pressure are given medication to lower or keep their blood pressure under control. Sometimes these can be very effective and cause blood pressure to drop. Trauma: A stroke, accident, or other trauma can damage the nerves that regulate blood pressure. Dietary triggers: Certain foods that trigger migraines can also cause dizziness or fainting after eating rice, including alcohol, nuts, dairy products, and chocolate. la, foods containing MSG and pickled foods. Certain medications: Drugs with a high risk of causing a drop in blood pressure are diuretics, alpha blockers, beta blockers, drugs used to treat Parkinson's disease, some antidepressants, and medications used for the treatment of erectile dysfunction.

4. How to diagnose and treat postprandial hypotension?

Patients need to be examined and perform a number of paraclinical indications to determine postprandial hypotension as well as rule out other diseases that cause fainting after eating:
Monitor blood pressure both before and after eating. and after meals for a period of time to record the degree of postprandial hypotension; Blood tests to check for anemia or low blood sugar; Electrocardiogram to look for heart rhythm problems or arrhythmias; Echocardiography to evaluate the structure and function of the heart.

To date, there is no permanent or 100% cure for postprandial hypotension. Even prescription medications are meant to alleviate the condition. However, there are various preventive measures to help minimize the condition:
Increase the intake of whole grains in your daily diet: Whole grains and fruits and vegetables that are rich in fiber slow down the aging process. digestive process, thus preventing spikes in blood sugar after meals, limiting the risk of low blood pressure or fainting after eating. Split Meals: It's better to have smaller and more frequent meals, to avoid eating too much at once. Drink water before meals: Drinking a glass of water 15 minutes before a meal can prevent the subsequent drop in blood pressure. Light activity after meals: During the hour after a meal, it is best to sit or lie down to prevent dizziness. If you have to get up from a sitting position, do it slowly and not suddenly. Avoid alcohol and foods high in salt, either before or during meals. In summary, postprandial hypotension has many different manifestations, ranging from benign to very serious. In these cases, the cause cannot be diagnosed based on symptoms alone. Therefore, it is important for a person who frequently faints after eating rice to have a medical examination and tests done to choose the right treatment.

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Reference sources: kauveryhospital.com, fyzical.com, verywellhealth.com, kauveryhospital.com