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What is Reactive Hypoglycemia?

Debra Durkee
Debra Durkee

Reactive hypoglycemia occurs when an individual suffers from a drop in blood sugar just after eating a meal. Symptoms of the condition can be easily mistaken for a number of different illnesses, and include trembling, muscle weakness, and lightheadedness. One of the major causes of the condition can be consuming a meal with a high sugar content. The condition can be difficult to diagnose, as the symptoms are often associated with other illnesses. Many individuals do not make the connection between the symptoms and sugary foods, as it is sometimes surprising how much sugar is contained in processed foods.

The condition is also sometimes referred to as alimentary hypoglycemia. Most commonly, hypoglycemia is associated with diabetes and a malfunction in the way the body produces insulin to regulate the body's blood sugar levels. In this form, the insulin produced by the body doesn't work as well, and administering regular shots of insulin is usually not necessary.

Those with hypoglycemia experience a drop in blood sugar after eating a meal.
Those with hypoglycemia experience a drop in blood sugar after eating a meal.

Symptoms of reactive hypoglycemia usually set in a couple hours after eating a meal. They can include fatigue, a racing heartbeat, and headache or a feeling of lightheadedness. There may also be mental symptoms, such as an unexplained feeling of nervousness or anxiety, sadness, or other types of changes in mood. The individual may also suddenly develop a craving for more sweet foods, especially if the meal just consumed was heavy in sweet sugars. He or she may also feel hungry again, regardless of how large the meal was.

Reactive hypoglycemia can occur in individuals who are not diabetic, but in some cases it can be a precursor to developing the condition. Insulin is still produced by the body, but in these cases it does not act quickly enough to regulate the amount of sugar that has been consumed. In many cases, following a careful diet and regulating sugar intake can help prevent reactive hypoglycemia from turning into diabetes. Small, frequent meals can also help the body regulate its response to the sugar that has been absorbed into the system.

Reactive hypoglycemia differs from another kind, called fasting hypoglycemia, which occurs when there has been no food or sugar intake and there is a sudden drop in the blood's sugar content. This is the type more commonly associated with diabetes. Without taking proper care in following nutritional guidelines, reactive hypoglycemia may develop into the fasting type and require insulin injections to regulate.

Discussion Comments


I had this. Go see an endocrinologist if you get these symptoms, especially if you have a family history of type 2 diabetes. I am normal weight, but had severe reactive hypoglycemia and now take metformin. The medicine and eating a lower carb diet has helped me tremendously.

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    • Those with hypoglycemia experience a drop in blood sugar after eating a meal.
      By: zothen
      Those with hypoglycemia experience a drop in blood sugar after eating a meal.