You get up, stretch, reach for your meter and strips and excitedly conduct your first test of the day only to find your ketone levels are surprisingly low, even though you ate well the night before and have “fasted” ever since. Why?
Don’t worry. It has nothing to do with what you have or haven’t done. What you’re likely experiencing is called the “dawn phenomenon” or “dawn effect.”
The dawn phenomenon is a naturally occurring, early-morning increase in blood sugar (glucose) that occurs for pretty much all humans; it is not associated with food consumption, it has to do with biological processes called gluconeogenesis and glycolysis. It’s believed that the release of other hormones, such as cortisol, during the wee hours of the morning may play a part.
For some people, the morning blood-sugar elevation is significant. For others, it’s barely noticeable. Regardless, it’s a normal response by the body as it prepares to face the day. It’s not dangerous to people with diabetes or anyone else. There’s nothing you can or should do about it, other than take it into consideration if you test yourself for ketones (and glucose) first thing in the morning. (The dawn phenomenon is the reason we recommend you wait until you’ve been awake an hour or two before testing.)
The Dawn Phenomenon and Diabetes
People with prediabetes or type 2 diabetes are more insulin resistant and may or may not secrete enough insulin to optimally counter the dawn phenomenon. Those who don’t secrete enough will see their blood glucose rise more than others during the early morning hours. People with diabetes who want to reduce the impact of the dawn phenomenon can do so by choosing less carb-heavy meals or snacks before bedtime.