The A1C test, also known as the hemoglobin A1c or glycated hemoglobin test, is a blood test that provides information about a person’s average blood sugar levels over the past 2 to 3 months. The A1C test is used to diagnose and monitor diabetes, as it gives an indication of how well blood sugar levels are being controlled over time.
A normal A1C level is below 5.7%. Levels between 5.7% and 6.4% indicate prediabetes, and levels of 6.5% or higher indicate diabetes. The higher the A1C level, the poorer the blood sugar control and the higher the risk of diabetes complications like nerve damage, kidney disease, and vision problems.
Stress is a fact of life for most people. Work demands, family responsibilities, health issues, and other challenges can ramp up stress levels. Research shows that chronic stress can negatively impact physical and mental health in various ways. One of the potential effects is on blood sugar regulation. Some studies suggest stress can contribute to elevated A1C levels, especially in people who already have trouble maintaining healthy blood sugar.
How stress affects blood sugar
To understand how stress might lead to increases in A1C, it helps to first look at what happens in the body when we experience stress.
When we perceive a threat or demand, the nervous system kicks into high alert. The adrenal glands release stress hormones like cortisol and adrenaline. These hormones trigger the “fight-or-flight” response, increasing heart rate, blood pressure, and energy supplies to muscles. At the same time, body systems not needed for immediate survival slow down, like digestion and the immune response.
All this helps us deal with an acute physical or psychological crisis. But when stressful situations go on and on, it can put chronic strain on the body. Hormones like cortisol remain elevated, rather than returning to normal levels when the threat passes. Over weeks and months, high cortisol and other stress hormones prompt changes in blood sugar regulation:
- Cortisol alters insulin sensitivity and secretion. Insulin is the hormone needed to transport glucose from the blood into cells to be used for energy. Higher cortisol reduces cells’ responsiveness to insulin. It also moderates insulin secretion by the pancreas.
- Adrenaline inhibits insulin release and promotes higher blood sugar levels to provide quick energy to muscles.
- Stress hormones increase gluconeogenesis – the liver’s generation of glucose from sources like proteins.
- Cortisol causes the body to regain glucose from broken-down tissue to keep blood sugar up.
These mechanisms provide readily-available energy to deal with threats. However, when stress is prolonged, insulin resistance and higher glucose production continue long-term. The result can be more persistently elevated blood sugar if the excess glucose is not used for energy.
Stress effects on A1C vary
Research into stress and blood sugar provides mixed findings overall. Some studies show notable effects of stress on A1C, while others find less impact. There are a few factors that appear to influence the degree to which stress affects A1C:
Baseline glucose levels
People with higher baseline glucose tend to show greater increases in A1C related to stress. In those with well-controlled blood sugar, stress has less effect on raising A1C levels further.
For example, a 2012 study tested effects of an acute stress task on blood sugar in 56 adults without diabetes. Participants were assigned to drink either glucose or a placebo beverage prior to stress testing. In the placebo group, the stress task did not alter blood glucose levels. But in subjects who drank the glucose drink and started with higher baseline blood sugar, stress led to significant increases in glucose.[1]
Duration of stress exposure
Research indicates more sustained stress is associated with larger impacts on A1C compared to temporary stress.
A study in mice subjected groups to either chronic stress (over a period of weeks) or acute stress (two hours). Chronic stress exposure resulted in gradually worsening hyperglycemia and higher A1C. The acute stress did not have the same effect. The researchers noted the increase in A1C was directly proportional to the duration of stress.[2]
Severity of stress
Severe, traumatic stress that greatly activates the body’s stress response appears most likely to affect blood sugar regulation.
A study of patients hospitalized in intensive care found almost 40% developed hyperglycemia during their stay, even though they had normal glucose tolerance beforehand. The researchers attributed this stress hyperglycemia to the metabolic effects of high cortisol and catecholamine levels in response to severe illness.[3]
Genetic and lifestyle factors
Genes and health behaviors also play into individual responses to stress. For example, certain gene variations lead to enhanced sensitivity to glucocorticoids like cortisol. Lifestyle habits that worsen insulin resistance, like poor diet, inactivity, obesity, and smoking, can amplify the impact of stress as well.
Ultimately, it’s the combination of chronic stress and underlying metabolic risks that tend to produce the greatest changes in glucose regulation and A1C.
Typical stress-related A1C increases
Most studies looking at stress and A1C test effects of exposure to major stressors, like work pressures, relationship loss, or caregiving demands. On average, this research shows stress is linked to A1C increases of around .1% to .3% compared to A1C prior to the stressful event.
For example:
- In a study of 39 spousal caregivers of dementia patients and 19 control subjects, caregivers had an average A1C increase of .13% over a 6-month period. Controls’ A1C did not change significantly.[4]
- An analysis of over 5,000 workers found those with high job strain had average A1C levels .2% higher than those with low job strain.[5]
These may seem like small A1C bumps. However, for those already dealing with moderately high A1C levels, an extra .2 or .3% elevation could represent poorer blood sugar management. In some cases, it may be enough to push A1C over the diabetes threshold.
More severe stress, like that occurring with major illness, trauma, or bereavement, seems capable of inducing larger A1C spikes upwards of .5 to 1% or more.[6] But most research focuses on impacts of common high-stress situations that would elevate A1C modestly rather than dramatically in most people.
Managing stress to control A1C
If you’re experiencing high stress levels along with rises in A1C, it’s wise to take action to control both. Try these tips to minimize the effects of stress on blood sugar:
Focus on healthy coping skills
Unhealthy coping mechanisms like smoking, drinking, or emotional eating can worsen insulin resistance. Make efforts to manage stress in healthier ways like exercising, relaxing, or socializing. Cognitive-behavioral therapies help develop effective coping skills.
Prioritize good sleep habits
Getting inadequate or poor-quality sleep is not only stressful itself but can also disrupt glucoregulation. Aim for 7 to 8 hours per night and adopt good sleep hygiene habits like limiting electronics use before bed.
Be more physically active
Exercise helps burn off extra glucose and makes cells more insulin sensitive. Both aerobic exercise and strength training are beneficial. Work up to at least 150 minutes of moderate activity per week.
Follow a diabetes-friendly diet
Choose foods like vegetables, fruits, whole grains, beans, lentils, nuts, seeds, and lean proteins. Avoid added sugars and refined carbs that spike blood sugar. Portion control is also key.
Check blood sugar regularly
Monitoring your glucose levels helps you see how daily stressors affect you. You and your doctor can use the data to inform treatment adjustments to counter stress-related swings.
Explore stress-reduction practices
Yoga, meditation, deep breathing, massage, visualization, nature exposure, and mindfulness have demonstrated anti-stress and blood sugar-lowering benefits.
Consider therapy or medication
For high stress that’s hard to cope with on your own, seek professional treatment. Therapies like CBT and medications like antidepressants can aid severely stressed individuals.
The bottom line
Research overall suggests chronic stress can contribute to subtle to moderate elevations in A1C, especially for those with high baseline glucose levels. The impact tends to be most pronounced with longer duration, greater severity, and inadequate coping. By managing stress effectively and continuing to focus on healthy lifestyle habits, you can counteract stress-related increases in A1C and achieve better diabetes control. Monitoring your A1C and glucose patterns can help you and your doctor determine whether stress reduction techniques are helping optimize your blood sugar regulation.