If you experience hypoglycemia (low blood sugar) without prediabetes or diabetes, you may be experiencing reactive hypoglycemia.
What is reactive hypoglycemia?
Reactive hypoglycemia refers to low blood sugar (hypoglycemia) that occurs after eating a meal. It typically happens within a few hours after eating, especially following meals high in carbohydrates.
When you eat carbohydrates, your body releases insulin to help regulate your blood sugar levels. Sometimes, the body releases too much insulin in response to a meal, causing blood sugar levels to drop too low.
What are the symptoms of reactive hypoglycemia?
Symptoms of reactive hypoglycemia typically occur within a few hours after eating a meal.
These symptoms of hypoglycemia can vary in severity and may include:
Shakiness or tremors
Sweating
Palpitations or rapid heartbeat
Hunger
Irritability or nervousness
Fatigue or weakness
Dizziness or lightheadedness
Difficulty concentrating
Confusion
Headaches
Blurred vision
Anxiety
In people without diabetes, clinical hypoglycemia refers to blood sugar less than 3.1 mmol/L. However, people will sometimes experience symptoms of hypoglycemia before blood sugar drops this low. Symptoms often resolve after eating carbohydrate-containing foods.
What causes reactive hypoglycemia?
The cause of reactive hypoglycemia is often unclear. These can include:
Issues with insulin sensitivity or the body's ability to regulate blood sugar levels: As a result of this, the body releases more insulin than needed to help regulate blood sugar levels, leading to a rapid drop in blood sugar.
Dumping syndrome: Dumping syndrome is a condition that can occur after certain types of surgeries (e.g. gastric bypass surgery, other bariatric surgeries) where the stomach is either partially or completely removed or bypassed. In dumping syndrome, food moves too quickly from the stomach into the small intestine, causing a spike in blood sugar followed by a sharp drop, leading to reactive hypoglycemia.
Hormonal imbalances: If the body is releasing too much or too little of hormones such as insulin, glucagon, or epinephrine, it can disrupt the body's ability to maintain stable blood sugar levels.
Underlying medical conditions: Conditions such as adrenal insufficiency, liver disease, and certain tumors (e.g. insulinoma) can increase the risk of reactive hypoglycemia.
If you suspect you have reactive hypoglycemia, it's important to consult with your physician or endocrinologist for proper diagnosis and management.
How is reactive hypoglycemia diagnosed?
Often, people first notice reactive hypoglycemia when they experience symptoms of hypoglycemia within a few hours after eating AND these symptoms resolve with intake.
Diagnosing reactive hypoglycemia can be challenging. Rather than one specific test, healthcare providers may use a combination of medical history, review of symptoms, and laboratory tests to make a diagnosis. Your doctor may also refer you to a specialist such as an endocrinologist for additional investigations.
Here's how reactive hypoglycemia may be diagnosed:
Medical history and symptoms: Your healthcare provider will ask you about your symptoms, including when they occur and what seems to trigger them. They'll also ask about your medical history, including any underlying medical conditions, medications you're taking, and your dietary routines.
Blood glucose monitoring: You may be asked to monitor blood sugar over several hours after eating a meal. If you have decided to monitor blood sugar at home without being advised to, it’s important to know that it is normal for people without prediabetes/diabetes to see blood sugar in the hypoglycemic range (<3.9 mmol/L). For most people, they will feel perfectly fine despite these lower blood sugar readings. However, please speak with your doctor if you experience symptoms of hypoglycemia with these lower readings.
Fasting glucose test: In some cases, a fasting glucose lab test (measuring blood sugar after an overnight fast of at least 8 hours) may be ordered to rule out other causes of hypoglycemia, such as fasting hypoglycemia or diabetes.
Mixed meal tolerance test (MMTT): This test involves drinking a meal replacement drink that contains a specific amount of carbohydrates, protein, and fat, followed by testing blood sugar, insulin, and C-peptide levels at regular intervals over the next few hours. This helps to assess how your body responds to a meal. In Canada, this is typically only performed in a hospital setting.
Medical imaging: In rare cases where an insulinoma (a tumor that produces excessive insulin) is suspected, imaging studies such as an MRI or CT scan may be ordered to visualize the pancreas and detect any abnormalities.
It's important to follow your doctor's recommendations for testing to determine the underlying cause of your symptoms. Once a diagnosis is confirmed, reactive hypoglycemia can be managed with dietary and lifestyle changes, and sometimes medications.
How to manage reactive hypoglycemia?
Managing reactive hypoglycemia typically involves a combination of dietary and lifestyle changes, and sometimes medication. Here are some strategies to help you manage reactive hypoglycemia:
Eat balanced meals: Focus on eating meals that provide a combination of protein, healthy fats, and carbohydrates. Both protein and healthy fats can be helpful in slowing down the absorption of sugar from carbohydrate foods. Preventing the sharp spike in blood sugar can help to mitigate the crash that results in hypoglycemic symptoms.
Eat smaller, more frequent meals: Spread out your carbohydrate intake across the day. Smaller portions at a time can again help to prevent a sharp spike in blood sugar, helping to mitigate the crash that follows.
Avoid/limit refined carbohydrates and fast acting sugars: Minimize your intake of sugary foods and beverages (e.g. juice, regular pop, sweets). These choices are usually absorbed fairly fast, resulting in rapid spikes and crashes in blood sugar.
Choose fibre-rich foods: Fibre also helps to slow down the digestive process, slowing down the absorption of carbohydrates, which can help prevent rapid fluctuations in blood sugar levels. Generally speaking, carbohydrate foods that are less processed or higher in fibre are more blood sugar friendly.
Low carbohydrate diet: If the above strategies do not work to adequately improve symptoms, you may benefit from a lower carbohydrate diet to minimize blood sugar fluctuations. While this is not usually the first strategy to try as it is more restrictive, this has been shown to be effective in a few studies and I have seen it work anecdotally among some clients.
Limit alcohol intake: Alcohol intake can increase the risk of hypoglycemia, as it interferes with your body’s ability to release stored sugar from the liver. If you are going to drink, limit how many drinks you are having, and be sure to pair it with food.
Exercise regularly: Exercise can help to improve overall insulin sensitivity, which can be helpful to support blood sugar stability.
Monitor blood sugar levels: You may be recommended to monitor blood sugar by your doctor. This can help to identify your blood sugar trends and allows you to make more informed adjustments to your diet and lifestyle.
Medication: In some cases, physicians may prescribe medications such as acarbose or diazoxide to help manage symptoms of reactive hypoglycemia. These medications work by slowing down the absorption of carbohydrates or reducing insulin secretion.
Work with a healthcare professional: It's essential to work closely with your healthcare team (e.g. doctor, endocrinologist) to correctly diagnose reactive hypoglycemia, and determine the best management plan. A dietitian can help to provide guidance on dietary and lifestyle changes specific to your needs.
References
Altuntaş Y. Postprandial Reactive Hypoglycemia. Sisli Etfal Hastan Tip Bul. 2019;53(3):215-220. Published 2019 Aug 28. doi:10.14744/SEMB.2019.59455
Kellogg TA, Bantle JP, Leslie DB, et al. Postgastric bypass hyperinsulinemic hypoglycemia syndrome: characterization and response to a modified diet. Surg Obes Relat Dis. 2008;4(4):492-499. doi:10.1016/j.soard.2008.05.005
Malik S, Mitchell JE, Steffen K, et al. Recognition and management of hyperinsulinemic hypoglycemia after bariatric surgery. Obes Res Clin Pract. 2016;10(1):1-14. doi:10.1016/j.orcp.2015.07.003
Rayas MS, Salehi M. Non-Diabetic Hypoglycemia. [Updated 2024 Jan 27]. In: Feingold KR, Anawalt B, Blackman MR, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com, Inc.; 2000-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK355894/
Advertisement
Comments