Severe anorexia or malnutrition may cause low blood sugar (hypoglycemia). Symptoms like dizziness, confusion, or weakness may develop without a sufficient supply of glucose in the bloodstream.

You can often resolve mild to moderate hypoglycemia cases by eating or drinking at least 15 grams of carbohydrates that your body can easily digest. This typically includes:

  • 4–5 salted crackers like saltines
  • 1 piece of fruit
  • 1/2 cup of fruit juice or non-diet soda
  • 1 tablespoon of honey or sugar
  • 3–4 pieces of candy
  • 1 cup of fat-free milk
  • 1 serving of glucose tablets

A doctor may also prescribe a glucagon injection if you’re at risk of severe low blood sugar. The injection can rapidly help stabilize your glucose level.

When to get immediate medical attention

Experts consider extremely low blood sugar a medical emergency.

If you or someone you know has any of the following symptoms, contact your local emergency services ASAP:

  • extreme dizziness or confusion
  • blurred vision
  • seizures
  • unresponsiveness
  • inability to drink or swallow
  • loss of consciousness

If possible, get yourself or someone with symptoms into the recovery position. If you have a glucagon injection on hand, give the injection right away.

It’s not safe for someone with extremely low blood sugar to drive, drink, or eat.

Malnutrition is a cause of muscle and body fat depletion and an insufficient glucose level in the blood.

Glucose irregularities may develop, especially when combining weight loss with excessive exercise. When your blood sugar plasma level drops below 70 milligrams per deciliter, experts consider this low and a reason for medical concern.

In a 2018 study involving people admitted to an internal medicine unit, those at an increased malnutrition risk had almost double the risk of hypoglycemia.

Research on the link between anorexia and hypoglycemia is also available. In a 2020 study involving people with anorexia and a body mass index (BMI) under 15, about 38% had hypoglycemia.

In a small 2022 study, researchers concluded that people with anorexia may be more likely to have chronic, prolonged, and mild hypoglycemia. However, more research is necessary to know for sure.

Low blood sugar may also develop when a person begins suddenly consuming more nutrients after a period of low caloric intake.

The increase in calories can cause metabolic and electrolyte issues that cause insulin and glucose levels to shift erratically — a condition called refeeding syndrome.

When this happens during nutritional rehabilitation, hypoglycemia may be treatable with strategies like:

  • enteral tube feeding
  • slow intravenous dextrose
  • meal-based management

Aside from insufficient nutrients in your diet, other factors may increase your likelihood of getting hypoglycemia, including:

  • unmanaged diabetes
  • not taking insulin medication as directed
  • certain medications (like quinine, used to treat malaria)
  • excessive exercise
  • heavy alcohol intake (which can prevent the liver from producing enough glucose)
  • critical illness (like sepsis, kidney disorders)
  • older age
  • pregnancy

Hypoglycemia may worsen without treatment. In many severe cases, hypoglycemia can cause:

  • heart disease
  • stroke
  • coma
  • seizures
  • nervous system damage
  • a higher risk of premature death
  • cardiac arrest

Hypoglycemia unawareness may also develop. When your blood sugar level drops frequently, you may become less aware of common hypoglycemia symptoms (like dizziness or confusion).

As a result, you might wait longer to take action, allowing your blood sugar level to drop low enough to cause a loss of consciousness.

If you think you have hypoglycemia, a doctor can help you create a treatment plan that can work for your needs.

Anorexia may lead to low blood sugar, especially in those with a BMI under 15.

Treatments for low blood sugar caused by anorexia may include internal tube feeding, dextrose injections, and meal-based management.

If you think you have low blood sugar, consuming a small amount of easily absorbable carbs (like 1/2 cup of fruit juice) can help raise your level.

If you think you may have disordered eating or anorexia, a therapist or doctor can help you find the right treatment for your needs.

For support, you can also call the National Association of Anorexia Nervosa and Associated Disorders at (888) 375-7767.