Anxiety can cause a measurable increase in blood sugar levels for a person without diabetes. This temporary elevation is not a sign of disease but rather a built-in survival mechanism. The body’s response to a perceived threat, whether physical danger or intense worry, automatically prepares itself for immediate physical exertion. This preparation involves a rapid hormonal signal that mobilizes the body’s primary energy source, which is glucose.
The Body’s Stress Response
The link between anxiety and glucose is governed by the sympathetic nervous system, specifically the “fight or flight” response. When the brain registers a threat, the adrenal glands release stress hormones, primarily adrenaline (epinephrine) and cortisol. Adrenaline acts quickly, instructing the liver to break down its stored form of sugar, called glycogen, through a process known as glycogenolysis.
This surge of readily available glucose floods the bloodstream, ensuring that muscles and the brain have the fuel necessary to run away or confront a danger. Cortisol, the other major hormone, sustains this energy mobilization over a longer period. It promotes gluconeogenesis, the liver’s process of creating new glucose from non-carbohydrate sources like protein and fat.
Cortisol also creates a temporary state of insulin resistance. By reducing the effectiveness of insulin, the hormone ensures that the newly released glucose stays circulating in the bloodstream instead of being immediately absorbed by muscle cells. This prioritizes the brain’s need for glucose during the stressful event.
Temporary Blood Sugar Spikes
In a healthy individual, the anxiety-induced blood sugar spike is typically mild and short-lived. Following the intense but brief hormonal surge, the non-diabetic body’s regulatory system quickly swings into action to restore balance. The pancreas responds to the excess glucose by releasing sufficient insulin, the hormone responsible for clearing sugar from the blood.
This effective insulin response rapidly moves the glucose into cells for use or storage, ensuring the blood sugar level returns to its normal range. While a non-diabetic person’s post-meal blood sugar will usually peak below 140 milligrams per deciliter (mg/dL), a severe anxiety event can cause a higher, yet still temporary, elevation. The body’s robust homeostatic mechanism is designed to handle these acute fluctuations efficiently.
The difference between a healthy response and a concerning one lies in the duration of the elevated glucose. For a healthy person, the blood sugar level should normalize within an hour or two of the anxiety subsiding, thanks to the quick action of insulin. This temporary spike is distinct from the chronic hyperglycemia seen in individuals with impaired glucose metabolism.
When to Seek Medical Advice
While anxiety can cause a temporary glucose increase, frequent or extreme spikes may signal an underlying metabolic issue that requires medical attention. If you notice that minor anxiety is consistently causing very high blood sugar readings, or if the elevation is prolonged, consult a healthcare provider. This may suggest that your body’s insulin response is not working as efficiently as it should be.
Chronically high blood sugar may be indicated by symptoms such as:
- Excessive thirst
- Frequent urination
- Unexplained weight loss
- Persistent fatigue
These symptoms may signal pre-diabetes or undiagnosed type 2 diabetes. A healthcare professional can perform specific blood tests to determine your average glucose control.
Tests include a fasting blood glucose test, which measures sugar after an overnight fast, and a hemoglobin A1C test. Pre-diabetes is indicated by a fasting glucose reading between 100 and 125 mg/dL, or an A1C percentage between 5.7% and 6.4%. If your anxiety-related symptoms align with these indicators, an assessment can help determine the next steps for maintaining metabolic health.