Symptoms of a sugar crash

A sugar crash, also know as hypoglycaemia, occurs when levels of glucose (sugar) in the bloodstream become abnormally low. Glucose supplies the energy needed to fuel brain function; therefore, maintaining stable levels of glucose is vital to physical and mental well-being. A sudden drop in blood sugar has devastating consequences.

Common sugar crash symptoms

Common symptoms of hypoglycaemia include heart palpitations, tremors, sweating, anxiety and hunger, according to Other symptoms include sluggishness and irritability. To prevent this type of sugar crash, limit simple carbohydrates -- sugary foods, snacks and soft drinks, and refined or highly processed foods and baked goods. For a sudden drop in blood sugar try a quick-fix food, such as 118 ml (1/2 cup) of fruit juice.

Sugar crash symptoms related to brain function

Specific brain functions impacted by abnormally low bloodstream levels of glucose include disorientation and behavioural changes, which prevent the completion of routine tasks, according to Other symptoms of severe hypoglycaemia include seizures and loss of consciousness.

Drug-related sugar crash

Hypoglycaemia is a side effect of medications prescribed to treat diabetes. Other medications have also caused sugar crashes, such as quinine and drugs used to treat kidney failure. Consuming alcohol on an empty stomach, especially in excessive amounts, interferes with liver function by preventing the release of glucose into the bloodstream. Hypoglycaemia occurs when this vital liver function that helps maintain sugar balance is blocked.

Illness-related sugar crash

Several medical conditions trigger hypoglycaemia by interfering with the normal metabolic processing of glucose. These conditions include hepatitis, kidney disorders, starvation, anorexia nervosa, pancreatic tumours and glandular disorders. Gastric bypass surgery places patients at risk of hypoglycaemia due to hyperinsulinemic hypoglycaemia (excessive insulin).

Aetiology of a sugar crash

Following consumption of large amounts of carbohydrates, especially simple carbohydrates, bloodstream levels of glucose rapidly increase. The sudden spike in blood sugar triggers the pancreas to secrete increased amounts of the hormone insulin. Insulin removes excess glucose from the bloodstream by transporting it to the cells, where it is used for energy. Excess insulin remaining in the bloodstream causes blood sugar to drop below normal levels, resulting in a sugar crash and a craving for more sugar.

Eating complex carbohydrates, which are digested more slowly than simple sugars, helps to maintain stable levels of glucose in the bloodstream. Adding protein and fat to a meal also slows the rate at which sugar enters the blood, helping to prevent spikes in glucose levels.

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About the Author

Sara Tomm began writing in 1971. She holds certificates in the medical, physiological and nutritional principles and treatment modalities for eating disorders. As a weight-management consultant, Tomm authored educational materials relating to the medical, psychological, environmental and social aspects of eating disorders, nutrition and physical fitness. She studied at Columbia University, Henry George School of Social Science, Farmingdale State College and Suffolk Community College.