Poor sleep, stress, prolonged fasting, and drinking coffee immediately upon waking are seemingly harmless things that can cause blood sugar levels to spike.
Many people believe that blood sugar only rises after eating sweets or starchy foods. However, Canadian naturopathic doctor Chirag Tandon, Director of Internal Medicine at ShardaCare-Healthcity, recently stated that many of the following daily habits can still raise blood sugar even when you haven't eaten anything.
Lack of sleep
Poor sleep can directly affect the body's ability to regulate blood sugar. According to Dr. Tandon, sleeping less than six hours a night can increase fasting blood sugar in the morning, even before eating. "Lack of sleep makes the body less sensitive to insulin, so glucose stays in the blood longer," he explains.
Lack of sleep also increases cortisol levels—a hormone that stimulates the liver to release more glucose into the bloodstream. Additionally, the body naturally tends to experience a rise in blood sugar in the morning due to hormonal changes (known as the "dawn effect"), and poor sleep can exacerbate this increase.
"To maintain stable blood sugar levels, especially for people with diabetes, it's essential to get at least 7-8 hours of restful sleep each night," Tandon advises.
Stress
Stress can raise blood sugar levels even without eating or drinking. When the body is under stress, hormones like cortisol and adrenaline are released to prepare for the "fight or flight" response.
"These hormones cause the liver to release stored glucose into the bloodstream for a quick energy boost," Dr. Tandon explained.
Prolonged stress can also increase insulin resistance over time. In addition, stress indirectly affects blood sugar by disrupting sleep or reducing physical activity levels. Measures such as regular exercise, meditation, relaxation techniques, and maintaining good sleep habits can help manage stress and stabilize blood sugar.
Skipping meals or prolonged fasting
Although intermittent fasting is popular for weight loss, this method is not suitable for everyone. Especially for those with endocrine disorders or metabolic problems, excessively long intervals between meals can cause significant blood sugar fluctuations.
When the body goes without food for an extended period, the liver releases stored glucose to maintain energy, sometimes causing a return to hyperglycemia. For people taking diabetes medication, skipping meals also increases the risk of hypoglycemia.
Because everyone reacts differently to fasting, experts recommend that this diet should only be adopted under medical guidance, especially for people with diabetes or chronic diseases.
Drink coffee instead of breakfast.
Many people start their day with a cup of coffee, even before eating anything. However, caffeine can affect blood sugar in some people. According to Dr. Tandon, caffeine can temporarily reduce insulin sensitivity, making it harder for cells to absorb glucose from the blood.
Caffeine can also increase cortisol, causing the liver to release more glucose into the bloodstream. If the coffee has added sugar, syrup, or cream for flavor, the increase in blood sugar can be even higher.
Tandon concluded: "Drinking black coffee in moderation is generally not harmful, but people with diabetes need to pay particular attention to their body's reaction."