Have you ever taken your fasting blood sugar and questioned why it was elevated? The occurrence of high blood sugar after a period of fasting is often puzzling to those not familiar with the Dawn Phenomenon or the Dawn Effect. It was first described about 30 years ago and it can occur in up to 75 percent of Type II Diabetics.
Just before awakening, around 4:00 am, the body secretes higher level of growth hormone, cortisol, glucagon and adrenaline. All of these hormones are excitatory which can raise blood sugar. They counter the blood sugar lowering hormone- insulin.
These hormones work in conjunction and are part of the normal circadian rhythm. During a deep sleep, these hormones start to fire to wake us up gently. Glucagon tells the liver to start pushing out some glucose. Adrenaline gives our bodies some energy. Growth hormone is involved in cell repair and the synthesis of new protein. Cortisol, the stress hormone, increases as a general activator. All these hormones peak in the early morning hours then fall to low levels during the day.
Since these hormones are full alert in the morning, we would think that our blood sugar would be at it’s highest. This does not normally happen, but why? Insulin also increases in the early morning so blood sugar doesn’t get too high. Blood sugar, even in non-diabetics, is never stable through the day. All hormones fluctuate through the day. Remember, blood work ups are just a snapshot in time. It is not an indicator of how your body might be a few hours later.
However in blood sugar dysregulation, people with insulin resistance, or having the precursor to Type II Diabetes, insulin has problems putting the breaks on- since the body isn’t listening to it’s signals. Since the counter hormones are still raising blood sugar, then we would expect the fasting blood sugar to be high.
A few hours after a meal, your insulin drops but the hormones that raise your blood sugar are still causing stored sugar to be released into the bloodstream. Insulin moves the sugar from the blood, where it can be seen, into the tissues (liver and muscles), where it cannot be seen. It is like moving the garbage from your kitchen to under your car seat. It smells the same, but you can’t see it. When insulin levels drop, that garbage starts to move back into the kitchen, and we see higher blood sugar.
This is where 12 or more hours of fasting comes into play. Purchasing a glucometer is a valuable tool to track where your blood sugar is at during the day. Say your last meal was at 6pm. You don’t consume breakfast until 6am the next day. That is a 12 hour fast. At which point you should take your blood sugar. If it is higher than 90, then there is some work to be done. Remember, an ideal blood sugar should read between 70-90. If you fasted 24 hours or even 48 hours and your fasting blood sugar has come into the range of 70-90, congratulations. We are now working on cleaning house of excess glucose. Where did that extra blood sugar come from? It could have only been from your own body, specifically the liver. If you see higher blood sugar during fasting, this does not mean you are doing anything wrong. It’s a normal occurrence. It just means that you have more work to do to clear out the stored sugar. And over time, fasting will do that. Remember, its not easy, but it is simple.