The content in this article should not be taken as medical advice. Please consult with your healthcare provider regarding your individual health needs.
In the intricate dance of our body’s biological rhythms, sleep plays a starring role, influencing not only our energy levels and mood but also our blood glucose (sugar) levels. While it's common knowledge that our blood sugar levels fluctuate during sleep, understanding the deeper reasons behind this phenomenon can shed light on how important quality sleep is for maintaining overall health and avoiding high blood sugar levels.
Is it normal for blood sugar to fluctuate at night?
The short answer is, yes. Fluctuations in glucose during sleep are part of the body's natural circadian rhythm and are impacted by various factors including sleep stages, time of day you’re sleeping, age, eating habits, and the amount of time you’re sleeping. It’s normal for glucose levels to increase at night—to a point.
Fluctuations at night can also be caused by the release of growth hormones during sleep. These are all factors to be mindful of when we begin to look at how our sleep patterns might be affecting our blood sugar.
Sleep deprivation: an enemy of optimal blood sugar levels
Regularly getting a good night’s sleep can help lower elevated blood sugar levels because your body’s systems will be functioning better overall. On the flip side, even just one night of sleep deprivation will increase insulin resistance, which can cause higher glucose levels. Ever notice how after a night of little to no sleep, you’re hungrier, crankier, and can’t think straight? Part of that is due to an increase in cortisol (the stress hormone) that occurs with poor sleep, which in turn causes elevated glucose levels.
Let’s look at some of the other reasons poor sleep may cause higher blood sugar levels:
- Decreased insulin sensitivity (also known as insulin resistance)
When you continually don't get enough sleep, your hormone levels can change. This can mean that you have less insulin available to balance your blood sugar, and more cortisol, a stress hormone that makes it harder for insulin to regulate glucose.
- Increase in oxidative stress and inflammation that impact glucose regulation
During sleep, blood pressure lowers. But when we don’t get enough sleep and blood pressure doesn't decline as it should, this can cause the cells in blood vessel walls to activate inflammation. Sleep deprivation can also alter the body's stress response system. - Elevated levels of C-reactive protein disrupt glucose regulation
Research shows that a lack of sleep is associated with increased levels of C-reactive protein—a marker of inflammation that's often elevated in people who are at risk for diabetes and other conditions such as heart disease and Alzheimer’s.
The catch-22 of poor sleep and increased blood sugar levels
So, we’ve learned that not getting enough sleep is not good for maintaining healthy glucose levels. To make things even trickier, if you already struggle with elevated blood sugar levels, that can also cause you to sleep poorly.
The relationship between glucose levels and sleep quality is bidirectional, meaning they both influence the other.
Sleep problems, such as insomnia, sleep-disordered breathing, and sleep apnea can lead to high blood sugar levels. And chronic sleep deprivation has been identified as a risk factor for the development of diabetes, emphasizing just how integral quality sleep is for metabolic health.
So, what can we do about it? Let’s take a look.
The answer: treat sleep like it’s your job
Quality sleep is not merely a luxury—it’s a necessity for maintaining optimal health and well-being. In a society where sleep deprivation has become increasingly prevalent, it can be hard to prioritize sleep when work, family, home, and social obligations are always competing for our time. But when we understand how negatively poor sleep affects our health, we can begin to make real change.
Read up on how to gear up for a good night’s sleep and start small with healthier sleep hygiene habits. If you think you have an underlying sleep disorder, talk to your healthcare provider about options. Take a holistic approach to your sleep health, that encompasses both lifestyle modifications and medical interventions when necessary. And lastly, be compassionate with yourself—it can take time to implement real change that allows you to catch all the ZZZ’s you need.
Curated & reviewed by: Jennifer Wenzel-Wamhoff
PharmD, BC-ADM, CDCES
PharmD, BC-ADM, CDCES
Jennifer Wenzel-Wamhoff is a highly experienced pharmacist with BC-ADM and CDCES diabetes certifications.
