When consuming foods high in added sugar such as candy and cakes, blood sugar levels will increase rapidly, causing the body to secrete insulin to put glucose into cells for energy.
However, a sudden increase in blood sugar, especially in the evening, can disrupt the delicate balance of hormones that regulate sleep-wake cycles, thereby negatively affecting sleep quality.
High sugar intake can cause a rapid spike in blood sugar, stimulating the body to secrete insulin to bring blood sugar levels back into balance. When blood sugar then drops rapidly, the body can continue to release hormones such as cortisol and adrenaline to regulate, thereby making you stay alert, even when needing to fall asleep.
When cortisol remains high at night, the natural increase in melatonin secretion can be inhibited. This is a hormone that plays a role in signaling the body that it is time to rest. Therefore, the imbalance between cortisol and melatonin can easily make it difficult for you to relax and get into sleep.
In addition, fluctuations in blood sugar also directly affect the depth and duration of sleep. A diet high in added sugar is associated with shorter sleep duration and multiple wakes during the night.
Rapid fluctuations in blood glucose can also disrupt REM sleep - an important stage in memory, learning ability and emotional regulation, while reducing deep sleep time, which is necessary for health recovery.
